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    Physics General Subjects Thread

    kvs
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    Post  kvs on Sat Mar 16, 2019 3:04 am

    GarryB wrote:
    This proper solution does not have the features of the claimed solution by Schwarzchild, Hilbert, et al.  The horizon is vanishingly small
    around the point mass.  So the homogeneous "black hole" solution is actually the case of two distinct space times with one imbedded
    in the other.  They key detail is that the inner space-time is displacing the outer space-time and not overlapping it.  This sort of
    material space-time behaviour in the absence of any mass-energy forcing (stress-energy tensor) is one of the innovative features of
    general relativity.  It is not true that mass-energy is required to tell space-time how to curve.  Space-time itself can induce curvature.

    Well that makes sense because in effect anything behind an event horizon can no longer be considered as being in this universe, there is a separation between the space time in this universe and the space time inside the black hole, for all we know the rules of space time in this universe might not apply at all, perhaps different rules from another reality of dimension reach through the singularity to the event horizon?

    We really need a quantum mechanics consistent theory of gravity before we can talk about he horizon as being a perfect 2D surface cleaving
    space into distinct pieces.   There has been no success at deriving a quantum gravity theory.   We have loop-quantum gravity and super-strings
    but we are still far from the end goal.    


    Clocks do not run faster in gravitational potential wells as the mass
    of the gravitating body is increased.  They run slower.

    Isn't that consistent with the speed of light and issues around dimensional space, mass, and  the passage of time?

    Time on an accelerating space ship does not slow down because the accelerating spaceship is getting heavier, it slows down because the speed is getting closer to the speed of light.

    It would also suggest that black holes are black because the only things that can escape them are 2 dimensional infinitely massive objects for which time in our universe has stopped so they are a non event in space time...

    The problem is that Special Relativity confused the subject.    It is an unnecessary and wrong theory based on a subjectivist postulate.

    1) Maxwell's  EM equations are invariant under Lorentz transforms

    2) Lorentz transforms were not created by Lorentz but are relevant by virtue of the EM equations having this invariance property.

    3) In light of (1) and (2), Galilean relativity is stone cold dead.   Inertial frames are deformed by virtue of having a speed.

    4) It is only in Galilean relativity where there is no absolute speed limit that transformed inertial coordinates are not deformed
    (i.e. the time axis is rotated towards the x-axis, the axis of movement as the frame speed increases).  

    5) It does not matter what a resident of some moving frame feels.   To him/her/it the time axis and the x-axis can
    appear to be perpendicular.   But to all other observers (i.e. the rest of the universe) he is Lorentz distorted and moving.
    Here is the critical failure point of Special Relativity.   It asserts that the subjective perception of a frame resident
    trumps all other observers and the objective reality that the frame is moving.   So we have:

    6) In SR a resident of any moving inertial frame always sets his speed to zero and any other frame he sees is supposedly
    the application of the Lorentz transform with some abs(v) > 0.   Since we do not have any observations that clearly
    demonstrate this "every other frame is moving faster than I am" ansatz, we get BS gedanken "experiments" supposedly
    proving this viewpoint.

    7) It is rather clear that (6) is simply nonsense.   In order for the observer to properly map all other frames (which can
    be slower, faster or the same speed (direction does not matter) it is an absolute requirement that he know his own
    speed.  In Galilean relativity one did not care since the frame speed had zero impact on the frame.   With the advent
    of Maxwell's EM equations we know that this is simply not physical.   Frames are distorted by their speed.  

    8 ) Since (7) no longer allows the v=0 hack, the frame resident will see frames moving faster than he is moving as
    exhibiting the usual SR effects: time dilation and length contraction (and failure of simultaneity).  But what Einstein
    and his gedanken experiments missed is that slower frames (remember that it is only the absolute speed that
    counts and not its direction in the Lorentz equations) will appear as time contracted and length dilated (and will
    also not have the same simultaneity along their axis of movement).  

    Summary: All observations attributed to SR are properties of the EM equations which govern our measureable reality since
    we are EM constructs.   The magnetic field around a wire does not require SR.   It requires Lorentz frame distortion.   The
    same solutions follow regardless of whether the wire is moving faster than the electrons depending on their direction of flow
    or the electrons in the wire are moving faster, there is a delta-v between the electrons and the protons in the wire metal
    atoms and hence they will not be in the same inertial frame.   A good indication that we are on the right path by dropping the
    BS (6) ansatz is that all the paradoxes (e.g. Twins, etc.) disappear.   They were logical contradictions induced by the
    unphysical ansatz (6).

    Your intuition is on the right track.  Photons know how fast they are moving as there is an absolute rest frame in which they live.
    The mere fact that some frame resident is moving does not cleave him off into another reality.   The subjectivism afflicting this
    field needs to go.   Clocks move slower in gravitational potential wells because photons paths are distorted and no longer Eulerian.
    The greater the field the stronger the impact.   Clocks actually stop at the horizon and any geodesic that touches the horizon
    must have local motion at the speed of light.   All attempts to fob off the horizon as a "coordinate singularity" are revisionist
    absurdity.
     

    Do black holes exist?  The above homogeneous solution is possible from the Big Bang.  But not from any stellar collapse.

    This does not make sense to me.

    Surely if anything is going to create one massive black hole it is compressing all the spacetime and matter of the universe into a point smaller than an atom even if it is only for the tiniest fraction of a second...

    But then a black hole is not just an enormous amount of matter, it also needs to be highly concentrated into a small area of space time.

    Of course one of the other problems is we talk about the fabric of space too much and we start considering it to actually be a fabric, which it isn't. The future expansion of space is described as leading to tears in the fabric of space, which doesn't make sense as space time isn't actually a fabric at all... we just use the term to describe something we still really don't understand properly.

    People are not free to abuse mathematics because of some supposed physical intuition (about singularities? Really?).   The GR equations embody all the
    physical axioms of the theory.   Solving for the unforced (no mass and energy) case is not solving for any stellar collapse problem.  It is not even solving
    for the end-point limit.   I already linked a paper that properly solves the GR equations for a point mass.   This is the general case that includes any (non
    rotating and non-charged) black hole singularity.    All black holes have finite masses.  It is their density that is infinite.  This exactly the point mass solution
    as given in the Castro paper.

    Any actual black solutions look nothing like the peculiar unforced solution being passed off on everybody.   There is no finite radius event horizon.  In fact,
    the event horizon is infinitesimal itself.   Allowing for quantum fuziness (i.e. no exact mathematical point but some vanishingly small volume) makes the horizon
    the surface of the singularity.   The end result of any stellar collapse is a "point" mass which does not involve the crossing of any horizon into a special bubble
    space-time and spiraling inward.  Sure, get close enough and you can't escape.   There is no longer any paradox as to how the gravity which supposedly does not have
    a speed faster than light can escape from the bubble enclosed by the horizon.    


    If we have neutron stars, then we are likely to
    have quark stars.

    If we have neutron stars where all the electrons have been crushed into protons to form and object consisting of only neutrons because of the enormous gravity, then further increases in mas when the gravity further increases and a quark star is created... is it interesting that you take the qu of quark and replace it with a d and get a dark start of enormous mass and small size and minimal emission of energy or heat.

    Hell for all we know the leading edge of space time might have an enormous thick shell of energy and matter that might be dragging space time out with it to expand into the empty void our universe is unfolding into. It might be dark matter because it is too far away to see and now it is moving too fast for us to ever see it.

    Space time might be more like a field, where objects in the field effect the field effects on other objects also in the field.

    The current orthodoxy is not helping is explore reality.   But the good thing is that all of these exciting possibilities are open and the field is
    not closed and dead.


    A quark solid would have densities much higher than the billion tons per teaspoon of neutron stars.  Before invoking an obviously
    incorrect framework to claim black holes, we may want to consider that quark solids do not have any glint from photon scattering and
    may emit any absorbed radiation at ultra low frequencies that none of our observational systems can detect.  If we are dealing with
    condensed dark matter objects then for sure they will have no glint and exhibit surface characteristics like those of the event
    horizon.

    But what about things even heavier than that... the earth weighs roughly  5.9 x 10^24 kgs, so 5.9 x 10^21 tons... which is a little more than a billion tons per 2cm sized ball.

    And what are up and down quarks made of and will further gravity reduce it to that in an even more dense state.

    What density of matter requires an escape velocity that approaches the speed of light?

    I would expect the tidal forces on any space ship would mean an event horizon is not needed to cause problems because even if you ship could move at a large fraction of the speed of light as it approached a quark star the tidal forces would shred it and render it incapable of powered flight anyway so escape would not be a possible option.

    It would only be with very very large black holes where the tidal forces are much less excessive near the event horizon where a ship might pass with out noticing the trouble it is in before getting close to the singularity and being shredded by tidal forces there.

    Surely the best argument against quark stars as an alternative to black holes is that they must be immensely hot and therefore not to be confused with black holes...

    As of now there are no proper stellar collapse solutions.   This is not due to lack of knowledge about super-dense states of matter which cannot be created in a lab.
    It is due to a hack solution based on pretending the homogeneous solution emerges (somehow) if the star gets compressed to a critical radius.    In light of the Castro solution,
    there is no magic bubble which would allow an event horizon to envelop a collapsing star at any stage other than the fully collapsed (point mass) stage.   So we
    can have all sorts of awesome states of matter compaction.   Gluon solids?   Or wholly new particles that no accelerator can generate.   At some stage we are dealing
    with the Planck scale and the quantum foam.  

    I have the totally wild idea that compressing matter to Planck-like densities results in some pure quantum emissions into the space fabric itself.   Instead of just
    compacting arbitrarily, the mass of the original star may dissipate in completely new ways (not just photon emissions).   This dissipation would affect the dynamics
    of the collapse.  

    As far as the homogeneous solution itself.   It may be that the "super-massive black holes" in galaxy interiors are primordial repulsive space-time bubbles formed during
    the big bang.  These bubbles act as gravitational attractors outside the horizon and would seed galaxy formation.
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    Post  flamming_python on Sat Mar 16, 2019 1:48 pm

    Well that makes sense because in effect anything behind an event horizon can no longer be considered as being in this universe, there is a separation between the space time in this universe and the space time inside the black hole, for all we know the rules of space time in this universe might not apply at all, perhaps different rules from another reality of dimension reach through the singularity to the event horizon?

    The universe is everything by definition. That's why it's called the universe. If God created the universe then he can be the only entity that's beyond it. All these terms like multiverse, etc... are just muddying the waters and are an attempt to seperate that about the universe which we can see but don't understand fully (the observable universe), from the parts of it that we do not see and cannot possibly understand yet (what's beyond an event horizon, what's beyond the observable portion, etc...).

    About the event horizon, anything can be beyond it. Speculation is nice and all but as most speculation that we do in life about things we cannot know - it tends to be an idle waste of time, just a little exercise for the brain.

    Mass does leak out of the black hole due to Hawking radiation - which is a consenquence of black holes being black bodies like everything else in the universe (i.e. they have temperatures). Eventually they do evaporate. So there is some interaction between what's beyond the event horizon and what's inside it; the energy does eventually get out. That stuff is not lost forever (it would violate conservation laws) and our current scientific understanding that does not suggest that it all gets deposited in some alternate reality.. in that case the black hole would actually be a white hole on the other side. And this other side will still be part of the universe.


    Time on an accelerating space ship does not slow down because the accelerating spaceship is getting heavier, it slows down because the speed is getting closer to the speed of light.

    Time on an accelerating space ship does not slow down at all. If you are on such a spaceship, you'd never tell the difference. Unless you looked outside. Then you'll see that the rest of the universe is running in fast-forward.

    Of course one of the other problems is we talk about the fabric of space too much and we start considering it to actually be a fabric, which it isn't. The future expansion of space is described as leading to tears in the fabric of space, which doesn't make sense as space time isn't actually a fabric at all... we just use the term to describe something we still really don't understand properly.

    It's not the fabric of space that tears; if you're talking about scenarios like the big rip.

    It's the acceleration of the expansion of space. Space itself expands and the distances between any two points will become larger over time. Some theories suggest that this expansion will keep accelerating into the future.

    If it does, the acceleration will reach a point where it starts to overcome gravity. First on the galactic cluster scale; all galaxies will begin to be perceived to be moving away from each other, even neighbouring ones - not just the further ones as we see now. Then galaxies themselves will begin to fall apart as the expansion overcomes gravity on the galactic scale; stars will become isolated. Then solar systems - planets will be seperated from their stars. From that point on the expansion of space would overcome the electromagnetic forces, the strong and weak forces in the nucleus - and all matter will fly apart.


    Hell for all we know the leading edge of space time might have an enormous thick shell of energy and matter that might be dragging space time out with it to expand into the empty void our universe is unfolding into. It might be dark matter because it is too far away to see and now it is moving too fast for us to ever see it.

    Based on our current understanding, it's not really how it works. There's no energy barrier paving the way for our universe's expansion at the frontiers or whatever. That's the equivalent of 2D thinking; like when people drew maps with 'there be dragons here' and huge waterfalls at the ends of the known world.

    Our universe doesn't expand into anything. Rather, everything in it is expanding away from everything else; as a consequence of a uniformal expansion of the space that we all exist in. At the moment, this expansion is entirely insignificant across short distances, and entirely counteracted by gravity. It's only noticeable when comparing far-away galaxies hundreds of millions of light years from each other, at the very least.

    The closest analogy is taking a deflated balloon, painting some dots on it to represent superclusters and threads of galaxies, and then inflating the balloon and watching how the distance between each dot increases relative to every other dot.


    If we have neutron stars where all the electrons have been crushed into protons to form and object consisting of only neutrons because of the enormous gravity, then further increases in mas when the gravity further increases and a quark star is created... is it interesting that you take the qu of quark and replace it with a d and get a dark start of enormous mass and small size and minimal emission of energy or heat.

    A neutron star doesn't exist only of neutrons. It's theorized that it's outer shell would consist of packed together Iron nuclei, the mantle would be neutrons, while the core may end up being made out of a sea of quarks.

    A quark star would probably have a crust of neutrons, a mantle of some sort of quark-gluon plasma, and a core of who knows

    A quantum experiment suggests there’s no such thing as Objective Reality

    Something of a vague term but if you're taking it to mean that reality is different for every observer, then surely not. The illusion of reality perhaps, but not reality itself. It always has to agree.

    Even in those examples about the spaceship travelling close to c and so. A passenger and an observer on Earth may not agree on what they saw, but they will agree on basic facts of reality. The passenger will return having aged a lot less than the observer; consistent as he saw the rest of the universe in fast-forward while the observer saw the spaceship in slow-motion.

    There's another thought experiment. Say you had a train travelling at close to c, and it passes through a tunnel under the mountain. The length of the train is longer than the length of the tunnel, but due to Lorentz distance contraction, to an outside observer, while in motion at such a high speed, the train would contract and end up a lot shorter than the tunnel.
    Very well, some engineers said - and installed a couple of giant guillotines over both the entrance and exit to the tunnel, configured to drop simultaneously when the train has fully entered the tunnel and then retract to let the train pass through as soon as they're dropped.

    An outside observer would see the contracted train pass into the mountain, the guillotines would drop, and then retract before the train reaches the end so that it can safely come out the other side.

    To a passenger inside the train, he doesn't see his train as having contracted at all. As far as he can see, it's still longer than the tunnel. Actually far, far longer, because from his perspective; the tunnel in front has contracted to a length of just a few metres, with the guillotines hanging menacingly overhead as his train approaches, much to his worry.
    So what happens?
    The answer is that when the head of the train enters the tunnel, the guillotine at the exit snaps shut, but then retracts before the train collides with it. The guillotine at the entrance stays idle, until the tail of the train has made it past it and into the tunnel - only then does it snap shut.
    So the simultaneous closing of both guillotines is not observed from the perspective of the passenger. However the end effect is the same for both the passenger and the observer. The train is whole and undamaged. The universe bends a few rules, but it doesn't violate causality and create different outcomes for different people.

    5) It does not matter what a resident of some moving frame feels.   To him/her/it the time axis and the x-axis can
    appear to be perpendicular.   But to all other observers (i.e. the rest of the universe) he is Lorentz distorted and moving.
    Here is the critical failure point of Special Relativity.   It asserts that the subjective perception of a frame resident
    trumps all other observers and the objective reality that the frame is moving.   So we have:

    You have an irritating habit of making even a casual discussion an exercise in deciphering Egyptian hieroglyphics.
    If you understand a concept well, then you should be able to explain it in simpler language and by referencing real-world examples.

    Loretzian distortion occurs for everyone equally, whatever reference frame. If someone is moving at close to c, to outside observers he will appear distorted. However, to him, everyone else will appear distorted. The same goes for perceptions of time. There is no failure, and there is no paradox. Observers may disagree on what they saw but causality (what actually happened) is preserved, reality is one for everybody.

    The
    same solutions follow regardless of whether the wire is moving faster than the electrons depending on their direction of flow
    or the electrons in the wire are moving faster, there is a delta-v between the electrons and the protons in the wire metal
    atoms and hence they will not be in the same inertial frame. 

    They won't be, but so what? We ourselves aren't in the same inertial frame with each other either. But the effects of this are entirely negligible. We'd have to be moving far faster in relation to each other for relativity to affect any of our interactions or perceptions.

    Photons know how fast they are moving as there is an absolute rest frame in which they live.

    From a photon's point of view, everything happens instantaneously. They emission, their absorption, and the whole path they've traveled. They have no conception of time or time passing.
    It's only us from our point of view, that see them travelling with a finite speed.

    Any actual black solutions look nothing like the peculiar unforced solution being passed off on everybody.   There is no finite radius event horizon.  In fact,
    the event horizon is infinitesimal itself.   Allowing for quantum fuziness (i.e. no exact mathematical point but some vanishingly small volume) makes the horizon
    the surface of the singularity.   The end result of any stellar collapse is a "point" mass which does not involve the crossing of any horizon into a special bubble
    space-time and spiraling inward.  Sure, get close enough and you can't escape.   There is no longer any paradox as to how the gravity which supposedly does not have
    a speed faster than light can escape from the bubble enclosed by the horizon.   

    These are all just theories, and are already being challenged.

    Singularities are the natural result of the mathematical formulas we've come up with. But that doesn't mean that this is what happens in reality. Mathematical formulas indicate all sorts of things that are logically impossible or inconsistent.

    There is one theory I'm sympathetic to about black holes being Planck stars, which you've touched upon a bit later in your post. Basically, the collapsing mass shrinks to the Planck length but can shrink no further, because that's the fundamental smallest length according to our current understanding. At that stage gravity is overcome and the mass starts expanding again, towards the event horizon. Only to the extreme levels of time dilation; we'll never observe this reversal - at least not until there's not a single reference frame in the universe other than that of black holes.

    As of now there are no proper stellar collapse solutions.   This is not due to lack of knowledge about super-dense states of matter which cannot be created in a lab.

    What do you mean there aren't? Matter, under extreme energy levels, undergoes transitions.
    Atoms to a sea of nuclei.
    Nuclei get transformed into their composite baryons; protons and electrons transition to neutrons.
    Neutrons get transformed into quarks.
    Quarks, under more gravity than they can handle, may undergo a transformation to bosons (i.e. photons and so on); for which the Pauli exclusion principle no longer applies and thus they can end up creating the energy density that would be required to form a black hole.
    We have observed some such transitions and can posit that this sort of thing will go on in a dying star.

    As far as the homogeneous solution itself.   It may be that the "super-massive black holes" in galaxy interiors are primordial repulsive space-time bubbles formed during
    the big bang. 

    Or they may just be supermassive black holes.
    Better to stick to the 'known unknowns' than the 'unknown unknowns', to borrow some terminology from Donald Rumsfeld.


    Last edited by flamming_python on Sat Mar 16, 2019 7:02 pm; edited 1 time in total
    jhelb
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    Post  jhelb on Sat Mar 16, 2019 3:11 pm

    nomadski wrote:
    @ihelb

    The scientist who said this , needs to be hit hard on the head with  a physics book . He will then be free to deny reality as much as he likes .

    You will notice nomadski that there are several studies that have been published in the last 50 years or so where all these researchers suggest that reality is actually an illusion. So this new research paper from MIT doesn't come as something unique.

    IIRC, there was an episode of Through The Wormwhole where this exact thing ( reality is an illusion) was discussed.
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    Post  kvs on Sat Mar 16, 2019 3:59 pm

    flamming_python wrote:
    5) It does not matter what a resident of some moving frame feels.   To him/her/it the time axis and the x-axis can
    appear to be perpendicular.   But to all other observers (i.e. the rest of the universe) he is Lorentz distorted and moving.
    Here is the critical failure point of Special Relativity.   It asserts that the subjective perception of a frame resident
    trumps all other observers and the objective reality that the frame is moving.   So we have:

    You have an irritating habit of making even a casual discussion an exercise in deciphering Egyptian hieroglyphics.
    If you understand a concept well, then you should be able to explain it in simpler language and by referencing real-world examples.

    Loretzian distortion occurs for everyone equally, whatever reference frame. If someone is moving at close to c, to outside observers he will appear distorted. However, to him, everyone else will appear distorted. The same goes for perceptions of time. There is no failure, and there is no paradox. Observers may disagree on what they saw but causality (what actually happened) is preserved, reality is one for everybody.

    What are you going on about?   You repeat one of the points I already made (that all inertial frames are Lorentz distorted by virtue
    of have a non-zero speed) and pretend that you are introducing this point.   I already made my case.   It is only in Galilean relativity
    that moving frames are not objectively distorted.    In Lorentzian relativity this is no longer the case.   Speed is real as is kinetic
    energy.   It is not about the perceptions of some observer.     SR is

    1) superflous since it adds absolutely nothing that does not follow from the Maxwell EM equations, i.e. Lorentzian distortion of moving
    frames and the absolute speed of light.

    2) introduces an ad hoc claim that the perceptions of some clown moving at a constant speed (that is, he feels that he
    is standing still) efine objective reality.    It is a manifest fact that the clown is moving with some speed v > 0.    
    This is what the EM equations care about.    And not the feels of the clown and SR cultists.

    You demand real world examples when you can't provide any yourself.   Take a hike, hypocrite.   The twins' paradox is a logical
    contradiction euphemistically called a "paradox" as if it can be resolved.   The usual one is contrived to invoke the supposed non-inertial
    transitions during the acceleration and deceleration stages as the resolution but there has never been a proof that any resolution follows.    
    That is by having one stay on Earth and the other go for a ride on a fast spaceship.    Well, the same "paradox" happens when you have
    both twins starting from their perceived v=0 inertial frame in two spaceships of the same type traveling along the same axis in opposite
    directions at large constant speeds and then coming back to the starting point.    This is a symmetric problem so any acceleration transition
    would apply the same for both.  But according to SR both twins see the other as aging less.   This results from the unphysical notion that
    their perceived v=0 is their actual v.   The universe clearly thinks otherwise.

    And BTW, any 3rd observer always sees the exact physical process.   Two spaceships approaching each other at 0.999c never
    exceed the speed of light in reality even if some observer on either spaceship expects and "sees" the oncoming ship to exceed
    its actual speed.   When two cars collide on the highway, it is the kinetic energy of both cars that wreaks them and not the
    perceived kinetic energy of the oncoming car from the vantage point of either driver.    Under the linearity of Galilean relativity
    one can be sloppy and pretend that it is the same.   But suppose that we are dealing with a truck and a bicycle.  The kinetic
    energy depends on their mass.   So the bicycle smashing into the truck at (v1+v2) is not physically equivalent to the truck smashing
    into the bicycle at (v1+v2) where v1 is the truck speed and the bicycle is speed is v2.

    E1 = 0.5 m1 v1^2 and E2 = 0.5 m2 v2^2 and  E_total = E1+E2

    E1' = 0.5 m1 (v1+v2)^2 or E2' = 0.5 m2 (v1+v2)^2 and  E_total = E1' or E2'

    but

    E1' >> E2'  and E1' > E1+E2

    E2' << E1+E2

    Clearly there is no energy consistency between the objective state and either of the perceived states even in Galilean relativity.
    This inconsistency of imposing the moving observer's perceptions as global reality gets even worse in Lorentzian relativity.   SR
    is a total steaming pile of nonsense that does not explain any observation that is not already explained without the subjectivist
    baggage.
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    Post  kvs on Sat Mar 16, 2019 4:15 pm

    jhelb wrote:
    nomadski wrote:
    @ihelb

    The scientist who said this , needs to be hit hard on the head with  a physics book . He will then be free to deny reality as much as he likes .

    You will notice nomadski that there are several studies that have been published in the last 50 years or so where all these researchers suggest that reality is actually an illusion. So this new research paper from MIT doesn't come as something unique.

    IIRC, there was an episode of Through The Wormwhole where this exact thing ( reality is an illusion) was discussed.

    Reality as illusion is a theme that goes back to the ancient Greek philosopher era and likely even earlier. In some sense even the
    various aboriginal tribe rights of passage (where they intake hallucinogens and go into cave for several days without food) are
    dealing with this issue as well. They are attempting to break through the apparent veil of reality into the spirit realm.

    So there is quite a bit of universality when it comes to this subject. That either indicates some sort of human brain pathology
    or an actual aspect of reality. The brain is always trying to model reality (even subconsciously) and may reach processing limits
    and fails to converge onto a solution in some fraction of all of its activity. This failure would likely be broadcast out of the
    subconscious and into the conscious as a feeling of inconsistency of perceptions.

    It is also likely that reality is more complex than what our brains can analyze. So our perception of reality is partial and not God-like.
    Things get really fun when quantum mechanics is considered. Our brains are entangling with various components of reality. Since
    we do not have an actual theory of wavefunction collapse by an observer it is possible that some steering occurs through state
    space evolution by existing matter and energy in the universe. This is very non-Newtonian.
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    Post  nomadski on Sat Mar 16, 2019 6:27 pm

    @ kvs

    God does not deceive his children . The devil does . God's laws  ( natural laws ) are knowable . God does not make contradictory laws  .  All these implies a weak God . Detracts from the all powerful god .

    Some who sell complicated theories , to make a living . Get lost in ever more complicated and abstract and meaningless formulae . And get others lost in them too .

    Einstein commented that God does not play dice . ( quantum theory ) . Others will advance well too , if they started with some meta physics .

    The ancient Greeks were wise . But they had many schools . Recent philosophers like Leibniz  , develops a modern meta physics . You could too start your own , by simply taking the first hypothesis of a perfect created universe and progress into how it might be best constructed .

    I got lost for a time , in the principia mathematica . As a late starter to maths , it was heavy going . And it seemed abstract and symbolic . I was rescued by liebniz . I realised that I could not effectively use maths to model the external reality . Although many beautiful formulae can be conjured up . That obey some regular laws or seem ordered . The external world may not comply with them .
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    Post  flamming_python on Sat Mar 16, 2019 6:38 pm

    kvs wrote:
    What are you going on about?   You repeat one of the points I already made (that all inertial frames are Lorentz distorted by virtue
    of have a non-zero speed) and pretend that you are introducing this point.   I already made my case.   It is only in Galilean relativity
    that moving frames are not objectively distorted.    In Lorentzian relativity this is no longer the case.   Speed is real as is kinetic
    energy.   It is not about the perceptions of some observer.

    You keep referencing these historical theories that are way out of date. Galilean relativity is a retroactive term meaning a pre-relativity Newtonian understanding of physics, while Lorentz never accepted General Relativity and its consequences. But basically his work took the side of Einstein's theories over the previous Newtonian model.
    The only accurate model we have is Einstein's theory of Special and General Relativity.

    Einstein himself never accepted Quantum Mechanics fully, and it could be that he will be proven right about that too; but the fact remains that Quantum Mechanics is our best theory at the moment and has enabled us to model phenomena that we never would have been able to without it.

    I mentioned Lorentzian distortion because it seemed as though you were arguing against it or dismissing the concept. Could be wrong of course - your posts are very difficult to decipher.

    kvs wrote:
    2) introduces an ad hoc claim that the perceptions of some clown moving at a constant speed (that is, he feels that he
    is standing still) efine objective reality.    It is a manifest fact that the clown is moving with some speed v > 0.    
    This is what the EM equations care about.    And not the feels of the clown and SR cultists.

    Of course it's objective reality. And the objective reality is that the flow of time and measurable distance do vary depending on inertia. The reality is the same for everybody. Different inertial frames will disagree on the passage of time for things outside their frames, but all these different observations will actually be consistent with reality at the same time despite appearing as contradictions from a Newtonian perspective. Like I mentioned in the example about the train going through the tunnel; the simultaneity of the guillotines dropped was disagreed upon - but both sides were right; because that's the nature of time and distance; they're not hard constants. And what was agreed upon is that the train wasn't damaged.

    If for one observer the train would be chopped into 3 pieces, and for another - the train would be unscathed; than that would be subjective reality, and a far greater problem than simply some disagreements about time and distance dilation. But we fortunately haven't seen anything like that in our universe so far.

    kvs wrote:
    The twins' paradox is a logical
    contradiction euphemistically called a "paradox" as if it can be resolved.   The usual one is contrived to invoke the supposed non-inertial
    transitions during the acceleration and deceleration stages as the resolution but there has never been a proof that any resolution follows.    
    That is by having one stay on Earth and the other go for a ride on a fast spaceship.

    Far from being a logical contradiction or unresolvable, the Twins Paradox is not actually even a paradox. It's an entirely accurate description, based on what we know, about how the twins would experience different amounts of time passing due to their inertial frames being wildly different, and reunite on Earth to see that one has aged and experienced less time passed than the other.

    And we've even seen evidence of the Twins 'Paradox' experimentally. Atomic clocks running on satellites in orbit ticking ever so slower. Highly-charged cosmic rays going at relativistic speeds and containing unstable particles that should have decayed long before they got to us - but haven't because from their point of view a lot less time has passed.

    kvs wrote:
    Well, the same "paradox" happens when you have
    both twins starting from their perceived v=0 inertial frame in two spaceships of the same type traveling along the same axis in opposite
    directions at large constant speeds and then coming back to the starting point.    This is a symmetric problem so any acceleration transition
    would apply the same for both.  But according to SR both twins see the other as aging less.   This results from the unphysical notion that
    their perceived v=0 is their actual v.   The universe clearly thinks otherwise.

    The Twins Paradox wouldn't happen in that case; if both twins were in different spacecraft traveling at the same speed; in whatever direction - in parallel, perpendicular, opposites.
    They would both return to Earth after 20 years to find that they've aged by exactly the same, no matter how many twists & turns they did or how many times they played chicken approaching each other with headlights on in deep space.

    It's called an inertial frame after all, not a velocity frame.

    Time dilation is really a consequence of Lorentz distance contraction. Speed is given by Distance/Time. As a spacecraft keeps accelerating, the Time taken decreases. As the spacecraft starts to approach the speed of light, with further acceleration, the Time taken keeps decreasing, but the Distance value starts to contract too.. so that S = D/T never quite yields 299,792,458 m/s.. the divisor and dividend of the formula both decrease.
    But that's from the perspective of someone on the spaceship.
    From the perspective of someone on Earth - the spaceship, as it continues to accelerate; will start having diminishing returns on reducing its Time taken, while the distance to its destination will remain constant. Thus the figure of
    299,792,458 m/s would never be hit either through the S = D/T formula.

    From that you can basically see how time dilation emerges. Because for someone on the ship, it would have taken a week to get to Alpha Centauri if they keep accelerating and contracting the distance in front of them, whereas from the perspective of someone on Earth it would have taken the ship say 5 years.

    Now back to your example about the Twins. For two spaceships, both travelling near c, in any direction - they would both witness the space in front of them/distance to their destination contract, whatever it may be. They would both also experience, from their own perspectives, that the time to their destination keeps decreasing the more they accelerate.
    Thus, they will experience the same level of time dilation, provided that they go at the same speed.

    kvs wrote:
    And BTW, any 3rd observer always sees the exact physical process.   Two spaceships approaching each other at 0.999c never
    exceed the speed of light in reality even if some observer on either spaceship expects and "sees" the oncoming ship to exceed
    its actual speed.

    Neither observer on either ship will ever observe light to be moving slower or the same speed as them. The light emitted by one approaching spaceship will always reach the other spaceship before the spaceship itself does.


    kvs wrote:Clearly there is no energy consistency between the objective state and either of the perceived states even in Galilean relativity.
    This inconsistency of imposing the moving observer's perceptions as global reality gets even worse in Lorentzian relativity.   SR
    is a total steaming pile of nonsense that does not explain any observation that is not already explained without the subjectivist
    baggage.

    There is no inconsistency nor subjectivity. You simply misunderstand the theory.
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    Post  GarryB on Sun Mar 17, 2019 11:17 am

    We really need a quantum mechanics consistent theory of gravity before we can talk about he horizon as being a perfect 2D surface cleaving
    space into distinct pieces. There has been no success at deriving a quantum gravity theory. We have loop-quantum gravity and super-strings
    but we are still far from the end goal.

    But when stuff doens't add up don't you just make up some shit like a universal constant, or dark matter and dark energy?

    It is a cheat, but better than most religions who say god did it and then refuse to discuss any alternative...

    The thing I like about science is that often when we really don't know but exploring finds something new they are not afraid of unravelling stuff we thought we knew and changing direction with new ideas...

    I also like the state of affairs that black holes have not been created in lab experiments so we can't be sure they exist... if that is the case I would prefer they remain a mystery... they can still use them in science fiction as devices for time travel or exploring alternative realities.

    The problem is that Special Relativity confused the subject. <snip></snip>absurdity.

    As I read through all that it seems to make sense, though I really don't fully understand what you said it did sound logical, but as I didn't check the various references or terms I would not really be able to repeat it coherently or logically, as I took what I knew before to make sense without totally understanding that either, I can now say that it is not true but am less able to explain why because the reality seems much more complicated... certainly probably more complicated than it needs to be... part of my problem is that you don't need to understand tidal forces to be ripped to shreds in orbit above a neutron star, so I don't see why your perception from a spacecraft travelling at near the speed of light effects the potential existence or otherwise of a post primordial black hole... especially when actually travelling at the speed of light or near it has not be achieved yet.

    Comparing atomic clocks both on earth and taken into space in a relatively fast moving space ship proved a time difference when the clocks were brought back together... does that not show speed effects time?

    Isn't also therefore obvious that the fastest you can move would also be the slowest time passage rate, which would also logically prevent travelling at that speed?

    My understanding was that travelling at the speed of light was impossible but faster than light was possible... but does that suggest beyond infinite mass, negative measurement in one dimension and time moving backwards so basically when you pass the speed of light a negative twin is created that bounces off you... yeah, I don't know where that is going...

    All black holes have finite masses. It is their density that is infinite. This exactly the point mass solution
    as given in the Castro paper.

    So you are saying all the mass that has ever entered a primordial black hole is still there compressed into a point in space smaller than the smallest known particles?

    That would mean the event horizon is not a disconnect from this universe to an outside this universe space because the gravity the BH exerts is real and does pass through the event horizon...

    There is no longer any paradox as to how the gravity which supposedly does not have
    a speed faster than light can escape from the bubble enclosed by the horizon.

    What if we just don't understand gravity properly... maybe it is not a wave, maybe it is a field that effects spacetime.

    It is the empty space between areas with matter that seem to be expanding the fastest, maybe flat spacetime with no matter to hold it, to curve it, just naturally expands continuously, but the areas with mass create a sort of spiderweb that slows down the expansion... but of course as the universe expands the support and structure of the... well they are galaxy and galaxy clusters is spreading thinner and thinner.

    If we want to visit a galaxy far far away we had better get our skates on and develop a blink drive or hyperspace or something...

    My personal favourite would be Dr Who, but he is so damn English... occasionally when you see Russians on it it is the skewed and perverted view of colonial england...


    I have the totally wild idea that compressing matter to Planck-like densities results in some pure quantum emissions into the space fabric itself. Instead of just
    compacting arbitrarily, the mass of the original star may dissipate in completely new ways (not just photon emissions). This dissipation would affect the dynamics
    of the collapse.

    Personally I would like a theory that gets rid of dark matter and dark energy... it seems to me to be a cheats way out to explain what has been observed and what is supposed to be there... there is more there... we just can't detect it...

    Well how about all the previously created black holes if we now think they are not actually black holes with event horizons and enormous amounts of matter sucked out of the universe to who knows where, but are actually just super dense piles of super heavy super compressed material.... maybe that is all the matter they can't find...

    The universe is everything by definition. That's why it's called the universe.

    Yeah, but the concept of the universe is a human concept... a horse wouldn't understand what you were talking about.

    If this universe exists, who is not to say others don't... something might have existed before and something might exist after, but we are just not in a position to see.

    Have seen a few very interesting ideas regarding this... for instance for bacteria this universe is two dimensional when in a water drop on a slide for a microscope, but fully 3D when it is floating around your bloodstream.

    For a tree there is no concept of light... they have no light receptors like eyes but they can detect heat which they interpret as sunlight... a plant will grow towards sunlight coming in a window, but it will also grow towards a heat lamp not realising it is not the right kind of light for photosynthesis.

    If God created the universe then he can be the only entity that's beyond it.

    If God is the mother of all creation surely it would be a she, and it is only man dominated religion that suggests it has any gender at all... being an all powerful being why would it even need a gender except be given one by a male dominated religion.

    in that case the black hole would actually be a white hole on the other side. And this other side will still be part of the universe.

    What if a black hole leads from out universe into a newly created universe... how else could you describe a big bang except a white hole?

    What if our universe is the result of an enormous black hole formed in another much bigger much older universe and the big bang here is the result of all that matter being blow through into our universe... all the matter smashed down into hydrogen and some helium... the most basic elements that are stable on their own....

    Time on an accelerating space ship does not slow down at all. If you are on such a spaceship, you'd never tell the difference. Unless you looked outside. Then you'll see that the rest of the universe is running in fast-forward.

    I don't see how looking out of a space ship will tell you how fast time is travelling... it would not be like the movie the time machine where cities are built up and fall in the blink of an eye as time races forward... Tests have been done with highly accurate atomic clocks... on kept on earth and one on a space station for 6 months or so and the one from the space station was running noticeably slower than the one from the ground...

    It's not the fabric of space that tears; if you're talking about scenarios like the big rip.

    It's the acceleration of the expansion of space. Space itself expands and the distances between any two points will become larger over time. Some theories suggest that this expansion will keep accelerating into the future.

    If it does, the acceleration will reach a point where it starts to overcome gravity. First on the galactic cluster scale; all galaxies will begin to be perceived to be moving away from each other, even neighbouring ones - not just the further ones as we see now. Then galaxies themselves will begin to fall apart as the expansion overcomes gravity on the galactic scale; stars will become isolated. Then solar systems - planets will be seperated from their stars. From that point on the expansion of space would overcome the electromagnetic forces, the strong and weak forces in the nucleus - and all matter will fly apart.

    The empty space between galaxies is expanding but the space between atoms and sub atomic particles is not, nor is the distance between objects within galaxies... stars are not getting bigger galaxies are not expanding and wont fall apart...

    The distance between the atoms in your body wont lead to your body collapsing in a pile of subatomic particles any time soon.

    There is talk of the fabric of space between galaxies being stretched too far and ripping... but that is again the analogy of a fabric... where would the holes lead?

    If the enormous energy of a huge concentration of mass can't punch a hole in space time how could simply stretching it do that?

    Based on our current understanding, it's not really how it works. There's no energy barrier paving the way for our universe's expansion at the frontiers or whatever.

    We have no idea... an expanding wave of matter an energy that came from an infinitely small point and expanded... what is it expanding into... what was there before... we have got no idea... just as we have no idea of what the bow wave of our expanding universe looks like... we can't see it and because of the distance we probably never will because it is getting further away all the time.

    Your balloon analogy is similar to the one I was told: If you think of a big long elastic band and attach a dot every few cms along it... each dot represents a galaxy... when you stretch the elastic all the galaxies are moving away from each other at the same time and it is difficult to see where the middle one is from any one galaxy because they all seem to be moving away...

    That is a good description of what we see, but tells us nothing about what the universe is made of, where did it come from and where is it going... what was there before, what did it expand into?

    It also adds some preconceptions... balloons burst when stretched to far and so do elastic bands, but we have no reason to assume space time will ever stop stretching or rip or even rebound...

    That's the equivalent of 2D thinking; like when people drew maps with 'there be dragons here' and huge waterfalls at the ends of the known world.

    That is all we have because there is no way we can see what happened and we wont be in a position to travel and explore to fill in the gaps...

    Something of a vague term but if you're taking it to mean that reality is different for every observer, then surely not. The illusion of reality perhaps, but not reality itself. It always has to agree.

    Careful... it is a slippery slope from Physics and observers, and Philosophy and perception... you rely on your senses for perception and your senses can fail you, therefore everything is imagined and nothing is real... quite logical but not really a useful or practical way to live your life.

    Conversely if physics can sort out these gravity waves and create unlimited energy and high speed galactic travel then that would be much more useful.

    So the simultaneous closing of both guillotines is not observed from the perspective of the passenger. However the end effect is the same for both the passenger and the observer. The train is whole and undamaged. The universe bends a few rules, but it doesn't violate causality and create different outcomes for different people.

    And any police officer will tell you if there is a car accident and there are 20 witnesses no two stories will be the same even though the incident happened only once.

    Reality as illusion is a theme that goes back to the ancient Greek philosopher era and likely even earlier.

    Philosophers love that because you don't need real examples and it comes down to internal logic... no one can prove you wrong, they can only fault your logic.

    Anyway good to see this thread pick up.

    As a Mod I would like to warn everyone to play nice and behave... no name calling or abuse please, or there will be trouble... this is not kindergarten stuff so you should not be surprised if different people either do not understand or have a different understanding of the same thing as you.

    PATIENCE AND RESPECT... OR ELSE...
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    Post  nomadski on Sun Mar 17, 2019 8:03 pm


    Now take for example , this idea of the number of atoms ( the type CERN are still looking for ) in the universe . What can we say , from our first principles , about this number ? The possibilities are :

    ( 1 ) Less than one . In this case , the atom can not have a closed continious surface , and therefore can not have any permanent quality. Nor arrange itself along others to create diversity. This diminishes from the power of God .

    ( 2 ) One atom . This atom , then should contain all desirable qualities . But in a static and uniform state . Leading to static universe . This diminishes from the goodness of god . Holding the created in an static state .

    ( 3 ) Many atoms . ( the number of usual atoms has been worked out ) . This would allow collections and collisions and movement and evolution of forms and diversity . Is consistent with the power of god .

    ( 4 ) Infinite number of atoms . This means that god can not arrange the desirable qualities in atoms , needing unending material to build the universe .

    This deductive reasoning from hypothesis , can be applied to various aspects of cosmology . Anything from supposed barriers in black holes , to what happens at the singularity . Etc .
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    Post  flamming_python on Sun Mar 17, 2019 9:03 pm

    GarryB wrote:I also like the state of affairs that black holes have not been created in lab experiments so we can't be sure they exist... if that is the case I would prefer they remain a mystery... they can still use them in science fiction as devices for time travel or exploring alternative realities.

    We haven't created other types of stars either but we're sure they do exist.
    Black holes are predicted by theory and have been observed by their effects.

    GarryB wrote:
    It is a cheat, but better than most religions who say god did it and then refuse to discuss any alternative...

    The thing I like about science is that often when we really don't know but exploring finds something new they are not afraid of unravelling stuff we thought we knew and changing direction with new ideas...

    I don't see a conflict between science and religion.

    The conflict only comes if they attempt to answer each other's questions. Which isn't possible and leads to logical inconsistencies because they exist to answer different things. Religion about the why and the who, and science about the how and the when and where.

    GarryB wrote:
    So you are saying all the mass that has ever entered a primordial black hole is still there compressed into a point in space smaller than the smallest known particles?

    That would mean the event horizon is not a disconnect from this universe to an outside this universe space because the gravity the BH exerts is real and does pass through the event horizon...

    That's correct. If all the mass exited it already then why would it still exert so much gravity?
    Then again, due to the event horizon, time dilation and the fact that gravity seems to work at light speed too; maybe from our point of view the mass in the black hole takes an infinitely long time to exit at the other side.
    So for all intents and purposes it never exits and is still in there, even if you were to be correct.

    GarryB wrote:
    What if we just don't understand gravity properly... maybe it is not a wave, maybe it is a field that effects spacetime.

    It is the empty space between areas with matter that seem to be expanding the fastest, maybe flat spacetime with no matter to hold it, to curve it, just naturally expands continuously, but the areas with mass create a sort of spiderweb that slows down the expansion... but of course as the universe expands the support and structure of the... well they are galaxy and galaxy clusters is spreading thinner and thinner.

    That was actually the prevailing chain of thought by the end of the 19th century - ether theories they were called. Einstein's theories put a stop to them, as Special Relativity could explain all the same things without the need for an ether.

    That's not to say there wasn't something to them. But if there is our science isn't capable of figuring out what exactly just yet.

    GarryB wrote:
    Yeah, but the concept of the universe is a human concept... a horse wouldn't understand what you were talking about.

    If this universe exists, who is not to say others don't... something might have existed before and something might exist after, but we are just not in a position to see.

    But what others?
    The universe is everything that exists and ever will exist. If we found something that exists outside our understanding or observation of the universe, a parallel reality or whatever; then it must also be part of the universe - and we would need to extend our model of the universe to include it.

    GarryB wrote:
    If God is the mother of all creation surely it would be a she, and it is only man dominated religion that suggests it has any gender at all... being an all powerful being why would it even need a gender except be given one by a male dominated religion.

    Well according to the book God created man from his image, and women to accompany men.
    From that we can infer that God is a he, per what we can understand. Of course to understand a diety that exists above all these rules is an exercise in futility.

    In Genesis it lays out the order of the creation of the universe. It so happens that it matches the order that we've arrived at per our current theories.
    By chance? Probably. But then what's to stop the Bible's conception of God being a he being correct by chance too?

    GarryB wrote:
    What if a black hole leads from out universe into a newly created universe... how else could you describe a big bang except a white hole?

    What if our universe is the result of an enormous black hole formed in another much bigger much older universe and the big bang here is the result of all that matter being blow through into our universe... all the matter smashed down into hydrogen and some helium... the most basic elements that are stable on their own....

    I do see your point, about using the term universe to define another reality with different physical laws and time. The trouble is that using terms like multiverse or multiple universes implies that they aren't interconnected. Which in fact they must be, if a black hole on our side leads to a white hole on theirs. Nothing in existence is an isolated system, per our current understanding of science and specifically thermodynamics.
    That's why if we were to discover such, we would simply have to extend our model of the universe - to encompass different planes of matter/energy/time, much like we currently have different inertial frames in our current model.

    As for the big bang - it could be a white hole, it could be a Planck star reversing itself once it has eaten up everything else in existence, it could be a quantum fluctuation. We don't know, hence why phrases like 'how else could you describe' really don't belong here.

    GarryB wrote:
    I don't see how looking out of a space ship will tell you how fast time is travelling... it would not be like the movie the time machine where cities are built up and fall in the blink of an eye as time races forward... Tests have been done with highly accurate atomic clocks... on kept on earth and one on a space station for 6 months or so and the one from the space station was running noticeably slower than the one from the ground...

    It's a requirement else reality would not be consistent.
    If someone on a spaceship is observed to be moving in slow motion and aging slower, then the same person on the spaceship must be observing the rest of the universe to be aging quicker.

    Else from his point of view, how, after zipping around for 20 years at a fraction of the speed of light; would he arrive on Earth to find that everyone else has aged 100 years? Did they all suddenly become older in a fraction of a second when he landed.

    GarryB wrote:
    The empty space between galaxies is expanding but the space between atoms and sub atomic particles is not, nor is the distance between objects within galaxies... stars are not getting bigger galaxies are not expanding and wont fall apart...

    The distance between the atoms in your body wont lead to your body collapsing in a pile of subatomic particles any time soon.

    There is talk of the fabric of space between galaxies being stretched too far and ripping... but that is again the analogy of a fabric... where would the holes lead?

    If the enormous energy of a huge concentration of mass can't punch a hole in space time how could simply stretching it do that?

    Of course it is. Why would the space between our atoms be expanding any less than the space between galaxies?

    The only difference is the scale. At the real world scale or the subatomic scale, this expansion is absolutely insignificant.
    At a distance of 45 million light years from us, the cumulative effect of the expansion of all this space between us and that point adds up to something significant, and we would need to take it into account in our calculations.
    At a distance of 45 billion light years from us, the rate of expansion between us and that point approaches the speed of light. Light from galaxies beyond that distance will never reach us.

    The 'rip' in Big Rip doesn't refer to space-time being ripped apart. But to matter being ripped apart.

    GarryB wrote:
    We have no idea... an expanding wave of matter an energy that came from an infinitely small point and expanded... what is it expanding into... what was there before... we have got no idea... just as we have no idea of what the bow wave of our expanding universe looks like... we can't see it and because of the distance we probably never will because it is getting further away all the time.

    Your balloon analogy is similar to the one I was told: If you think of a big long elastic band and attach a dot every few cms along it... each dot represents a galaxy... when you stretch the elastic all the galaxies are moving away from each other at the same time and it is difficult to see where the middle one is from any one galaxy because they all seem to be moving away...

    That is a good description of what we see, but tells us nothing about what the universe is made of, where did it come from and where is it going... what was there before, what did it expand into?

    It also adds some preconceptions... balloons burst when stretched to far and so do elastic bands, but we have no reason to assume space time will ever stop stretching or rip or even rebound...

    Well if it's expanding into something that's already there, then it might just be more galaxies and boring stuff. Maybe big bangs are local phenomenon across our whole universe, which is actually massive beyond comprehension

    But if the big bang created all there is - then the universe is not expanding into anything. It's just expanding.
    Else will come the question - expanding away from where? Surely not from a point centered on little insignificant us.. or are you suggesting we go back to pre-Gallileo thinking again?

    From the perspective of Earth everything seems to be expanding away from us. Yet you can pick any point in the universe and observe the exact same effect; you're apparently in the middle again and everything else is expanding away from you. And with the exact same rates.
    So where then is this bow wave of frontier expanding into nothingness supposed to be then exactly? Where are we supposed to go in order to see it, even if we could go faster than the speed of light? 100 billion light years from us that way? Whoops we're now no better off than we started out as.
    Or perhaps lets go to the most distant galaxy we can see first then back towards Earth... Earth is so far away from us now, it can't be that far from that frontier now..
    Walther von Oldenburg
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    Post  Walther von Oldenburg on Sun Mar 17, 2019 10:21 pm

    I wonder - is there any way to destroy or at least significantly hasten the evapiration of a black hole? Hawking radiation is slow.

    kvs, farming python - what do you think?
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    Post  flamming_python on Mon Mar 18, 2019 1:48 am

    Walther von Oldenburg wrote:I wonder - is there any way to destroy or at least significantly hasten the evapiration of a black hole? Hawking radiation is slow.

    kvs, farming python - what do you think?

    Only by getting rid of all the background radiation of the universe and making it as cold as possible.

    At the moment all black-holes aside from the smallest micro black-holes are actually gaining mass from the cosmic background radiation, as they are colder than it, and are therefore not evaporating at present time and won't be until the universe expands and cools down a whole lot more.

    It would be interesting to see what would happen to black holes if the expansion of space accelerates; how will it affect them and will it hasten their departure?
    If there is a way to localize this phenomenon and rev it up to the max, then perhaps.
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    Post  GarryB on Mon Mar 18, 2019 9:39 am

    Well according to the book God created man from his image, and women to accompany men.
    From that we can infer that God is a he, per what we can understand. Of course to understand a diety that exists above all these rules is an exercise in futility.

    The problem is that where did the bible and such things come from... in many ways it is mostly a group of stories, some with morals, and others showing actions and consequences... a sort of how to live your life book... but how many women could read and write when these books were written... you can't just get your own copy by folding it flat and putting it in a photocopier... it was the job of scribes to sit and rewrite these things over and over to make copies for those that could afford them... what if you wrote one out and the rich man you wrote it out for decided that this can't be right... the mother of all creation a woman? Write it again and this time put in some crap about man being made in the image of god and have the woman as his companion... I guess we are lucky there wasn't a dog as a companion and woman as sex slave and kitchen and washhouse slave and of course bed warmer.

    I would be interested in reading about religions popular in matriarchal societies, but then I can't be bothered learning about religion at the best of times I am afraid and I rapidly lose interest.

    And no I am not a feminist, I consider women should be treated better than men, and not because they are fragile and weak, but because they are warm and soft and smell nice and fun to cuddle and do things to. clown
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    Post  jhelb on Mon Mar 18, 2019 11:18 am

    Researchers from the Moscow Institute of Physics and Technology teamed up with colleagues from the U.S. and Switzerland and returned the state of a quantum computer a fraction of a second into the past


    https://phys.org/news/2019-03-physicists-reverse-quantum.html?utm_source=quora&utm_medium=referral

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    Post  flamming_python on Tue Mar 19, 2019 4:26 pm

    GarryB wrote:
    The problem is that where did the bible and such things come from... in many ways it is mostly a group of stories, some with morals, and others showing actions and consequences... a sort of how to live your life book... but how many women could read and write when these books were written... you can't just get your own copy by folding it flat and putting it in a photocopier... it was the job of scribes to sit and rewrite these things over and over to make copies for those that could afford them... what if you wrote one out and the rich man you wrote it out for decided that this can't be right... the mother of all creation a woman? Write it again and this time put in some crap about man being made in the image of god and have the woman as his companion... I guess we are lucky there wasn't a dog as a companion and woman as sex slave and kitchen and washhouse slave and of course bed warmer.

    I guess the problem with this reasoning would be... how would this set of accounts from the followers of some carpenter traveling around Judea and surrounding lands in rags and sandals hundreds of years prior have come to be so highly regarded by all these rich men and scribes, and came to be adopted in their societies in the first place? Not to mention the beliefs and stories of the indigenous people of that region, which were also included in the Bible as the Old Testament.

    Couldn't these Europeans just write their own stories to justify their power over others? As a matter of fact they had them. Ares and Pluto and Venus and so on.
    Even the Greeks, the first people to come to the conclusion that there is a universal natural law that governs and connects seemingly seperate natural events, still believed in separate Gods which personified the behavior and outcomes of different facets of their lives and the natural world... crops, love, planetary motion, etc... If the seas rose it was because Poseidon willed it; even though they already had the science to suggest that there was something more to it.

    GarryB wrote: I would be interested in reading about religions popular in matriarchal societies, but then I can't be bothered learning about religion at the best of times I am afraid and I rapidly lose interest.

    That's a shame, because even though with the enlightenment and all it progressed to we've surely gained a lot. The idea of individual liberties, equality of the sexes, abolition of religious dogmas governing scientific discovery, etc... we've also lost quite a lot of that past wisdom too, and in some cases replaced it with moral relativism that helps decide nothing, or just replaced it with nothing at all.
    And other things that we thought we've done away with we've actually not done away with at all. Such as witch-hunting, and religious dogmas being replaced with ideological ones.
    With our aggressive campaign against religion, European (and East Asian) societies have entered into something of an identity crisis, and a state of denial. We think that we're now all so enlightened and progressive but really we're stepping on many of the same garden rakes and heading in an unpredictable direction. That's where we got Hitler from. And now, all the SJW idiots and neo-liberalism.

    Back in pre-Enlightenment Europe, religion was more than just the bible-quoting zealots we see today.. it was a philosophy that governed all aspects of society. It was a system of government. Of education. It was a code of laws and ethics. It was a life-goal, it was a set of virtues. It was a psychological and self-help routine. And all of it was fiercely debated and developed further. And a lot that debate furthered our understanding of reality and ourselves, in ways that contemporary philosophies do not even attempt to do, and science just won't touch.

    That question about whether God could create a stone so heavy he could not lift is a well known one. What isn't that well known is that this was an actual question that Christian theologians debated some 700-800 years ago, nor the conclusion that they came to. The answer they arrived at was no, he could not. God was omnipotent by definition, so he couldn't do something that would cause a logical contradiction or paradox and make him non-omnipotent. Such as creating such a stone, or killing himself. Because that doesn't make any more logical sense than saying 1 plus 1 equals 3. This mirrors, BTW, the way the universe avoids paradoxes, from what we've seen so far in regards to faster-than-light travel, the observer effect and so forth.
    What's interesting though is that humans can do that; because we're not omnipotent and cannot be.
    And from those sorts of questions we gain better understanding of these concepts such as omnipotence, logic, semantics, infinity and so on, and what the boundaries of each of them are. And perhaps a hint as to the purpose of life in the universe, if such a purpose indeed exists.

    The Muslims have a concept called Jihad. The popular conception for non-Muslims of Jihad is of a holy-war against infidels, or non-believers. But what Jihad actually amounts to is a battle against non-belief itself. And the greater part of this battle, or Greater Jihad - is the internal one against one's own non-belief that each Muslim must fight. In Islam it's believed that without a subservience to God, each human will succumb to and be governed by his selfish and carnal desires.. indeed this is what Said Qutb (the father of modern Islamism) thought he witnessed when he spent time in America in the 50s. Greater Jihad essentially entails a period of intense introspection to find all evil, bad-behaviours and character flaws within oneself. And when they're identified, they should not be suppressed, but realized for what they are and brought out into the open, into the full conscious recognition of the person. When one does this, he will regain his freedom of consciousness and action, free to ignore that which previously governed him subconsciously, and to do the right thing by God and by others.
    Again, philosophies which aren't religions have no concepts of such things. They can't guide a person into becoming a better one. They aren't nearly as developed and debated as have been the major world religions.
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    Post  GarryB on Wed Mar 20, 2019 12:53 am

    I guess the problem with this reasoning would be... how would this set of accounts from the followers of some carpenter traveling around Judea and surrounding lands in rags and sandals hundreds of years prior have come to be so highly regarded by all these rich men and scribes, and came to be adopted in their societies in the first place? Not to mention the beliefs and stories of the indigenous people of that region, which were also included in the Bible as the Old Testament.

    We really don't know who specifically wrote the bible, or even when, for all we know a traveller carpenter would be the ideal person to create such a collection of fables and old stories (old then, not just now) because the vast majority of the people of the time couldn't read or write so all their history will be verbal and their rules and culture would be verbal too because you couldn't just post a list of rules in the town square for everyone to read.

    Even more recently created religions have bibles of their own that include religious fables with lessons to live by, it could be argued they pinched them from other religions, but equally most cultures have fables and allegorys that would be some of the first things written down when writing things down became possible.

    Scribes of the day... when you make lots of copies over days and weeks, errors can occur and omissions are possible, and to tell you make a mistake the person first has to be able to read, and second needs to have read and remembered the original in great detail... hell, you could have a scribe that is pissed off and what a jerk his current employer is and make significant and intentional omissions or errors in the hope that one day he is spouting off and says something in front of people who know better and makes an arse of himself in front of people he is trying to impress...

    And further who is to say which versions survive to be found in the future and which are worn out or destroyed or simply lost.

    The beliefs and stories of the indigenous people could only be passed on down the generations by word of mouth, so 300 years after the events you could probably still go into those communities and get those and write them down... or if those people have moved away or no longer exist.... who is going to contradict anything you put there... you could either travel around and find where some of them moved to, or just find a good story and make it fit... the source is not so critical as the stories fitting the over all narrative...

    In many ways it is a bit like a Boy Scouts annual... a few moral stories and a few activity sections...

    [quote]Couldn't these Europeans just write their own stories to justify their power over others?[quote]

    The people already knew their own stories and could not really be controlled by them.... they needed an new all powerful god that comes with a new set of rules that suit them... get rid of all the local religions and paganism... create a nice unified christian society, but even that split up into fragments because people couldn't even just agree on that...

    Even the Greeks, the first people to come to the conclusion that there is a universal natural law that governs and connects seemingly seperate natural events, still believed in separate Gods which personified the behavior and outcomes of different facets of their lives and the natural world... crops, love, planetary motion, etc... If the seas rose it was because Poseidon willed it; even though they already had the science to suggest that there was something more to it.

    It was easier to sell... Poseidon controls the tide but being a good and orderly god he does it in an orderly way that we can learn to predict what he is doing... but strangely enough it seems to be related to the way some other god makes the moon appear... and then the two are put together and maybe Poseidon controls the moon as well as the sea and it starts to fall apart logically... and then someone starts talking about gravity, which means instead of using historical records to work out what the tide will do at any location you can now calculate it for any point on the planet...

    You start with religion being the only answer and explanation and records being used to predict future events, to science explaining what is happening and enabling not just future predictions for that specific harbour, but also accurate predictions for any harbour or place where land meets sea on the planet and even near rather big tidal lakes as well...

    We can use religion for questions like do we have a soul, and what happens to us when we die, but even for that you are talking more about comfort rather than accurate answers because the people who know are not in a position to tell us.

    It is also an area religious people are happy to talk about... because that is the sales section of religion... go with us or burn in hell for eternity...

    Buy our product or suffer forever... if you were selling cars or TVs using that method you would not last in business for long, but it sells really well for so many religions....

    which personified the behavior and outcomes of different facets of their lives and the natural world... crops, love, planetary motion, etc

    Well another factor is that farmers and people who depend on weather and nature are more in touch with nature and the stars... most people in big modern cities rarely look up.
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    Post  GarryB on Wed Mar 20, 2019 1:02 am

    The Muslims have a concept called Jihad. The popular conception for non-Muslims of Jihad is of a holy-war against infidels, or non-believers. But what Jihad actually amounts to is a battle against non-belief itself. And the greater part of this battle, or Greater Jihad - is the internal one against one's own non-belief that each Muslim must fight. In Islam it's believed that without a subservience to God, each human will succumb to and be governed by his selfish and carnal desires.. indeed this is what Said Qutb (the father of modern Islamism) thought he witnessed when he spent time in America in the 50s. Greater Jihad essentially entails a period of intense introspection to find all evil, bad-behaviours and character flaws within oneself. And when they're identified, they should not be suppressed, but realized for what they are and brought out into the open, into the full conscious recognition of the person. When one does this, he will regain his freedom of consciousness and action, free to ignore that which previously governed him subconsciously, and to do the right thing by God and by others.
    Again, philosophies which aren't religions have no concepts of such things. They can't guide a person into becoming a better one. They aren't nearly as developed and debated as have been the major world religions.

    I find that mildly offensive... are you suggesting that atheists are evil and behave badly and act selfishly and only on their own carnal desires?

    Is the only reason to be civil a fear of being rejected or punished by an all powerful and judging god?

    Can you really only be free consciously by following word for word the beliefs and misbeliefs of people from 2,000 years ago... I wouldn't put up with their plumbing standards or their hygiene standards, but I should follow their beliefs on relationships and marriage and behaviour?

    Interesting the current spell checker I am using tells me Christians needs a capital C and Muslims needs a capital M, but atheists don't need a capital a at all... is the english language athiphobic?

    ...Hahahaha and it is demanding I use a capital E for english, and did I mean to put homophobic instead of athiphobic?
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    Post  nomadski on Wed Mar 20, 2019 11:48 am

    We can not dismiss the intelligent design hypothesis . Since it has revealed the nature of cosmology . Since ancient times , it was known that matter was created , had a begining . And that matter can be destroyed  . And the universe will end . Ancients were wiser than we give them credit . The ancient Persians , for example had many  stellar observstories  and magi , who were astronomers . They knew the existence of planets . If it was not for the destruction of Persepolis and it's library at the hands of  Alexander , then who knows what,  knowledge would be discovered .  The Ash at the bottom  of this library , is several meters thick . Pointing to the possible existence of many manuscripts .  

    String theory , is based on mathematics derived by Ramanujan . He also relied on inspirations by a Hindu god for his mathematical formulations . Apparently these came to him,  while asleep . Such is power of meta physics that even an unconscious mind can be induced by it  .

    Hawkings , in his book , A brief history of time , revealed that the value of some atomic quality  , was so accurately fixed , that even a slight variation , would invalidate our present universe . Such exact fixation is beyound random chance events .

    At CERN , they recently discovered a particle that gives matter it's mass . They called this the " god particle " . Was this to appease the ignorant masses ? Or did someone think about , how god would do it ?


    Scientific reasoning  can be compared to having or possessing a small but perfect mirror . The variables can be studied using experimentation and quantitative  analysis . However scientific mathematical analysis  , is by nature limited and begins to fail , when considering a large number of related variables . In order to arrive at a real picture or reflection of reality  , many small mirrors can be arranged together . But there will be gaps . Discontinious transitions , where scale of observation , viewpoint of observer , gives different results . To resolve these theories , transitions in scale or time need to be studied , to find relationship of variables .

    Philosophocal , linguistic , logical , deductive reasoning gives different results . Depending on the accuracy of the original hypothesis , the relationship of variables can be fixed accurately . Like having a dulled mirror , where general shapes are visible , without gaps . But nothing is in sharp focus . Emperical reasoning is accurately inaccurate . Analytical reasoning  is inaccurately accurate . Pure reason and practical reason . Who was it that said that ?

    Now about other topics mentioned , such as human reproduction or public hygiene.  These are out of topic here   but who will moderate the moderators ?  Please open another topic . Briefly  , the Persians invented the shower head , many thousand years ago . Remember next time you have a shower !  It was not the French ! Not that I want to get into any quantum entanglement with a mod .


    Last edited by nomadski on Wed Mar 20, 2019 1:42 pm; edited 1 time in total
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    Post  Walther von Oldenburg on Wed Mar 20, 2019 12:14 pm

    The intelligent design 'theory' is just a smart sounding name for creationism. It doesn't have a theory of anything, just bashes evolution.
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    Post  nomadski on Wed Mar 20, 2019 3:46 pm

    Creationists do bash evolutionists . As do most university professors in science . Bash each other . Ever coming up with esoteric and convoluted theories . That only they can decypher . At a high cost . This does  not mean that these two theories are contradictory or at odds .

    Take for example the hypothesis of the omnipotence of god . Such a god , can create the world  , with it 's laws  in one instance . In such a way , that it required  no further interventions by  god .  Because such interventions would mean a weak god . Like a bad driver , who has to continuously  repair his car . Since he can not see a crash coming . Such a  powerful god , would install instructions into each Atom . So it has a mind  and  it knows it's journey . And knows it's destination . And sees where it is going . Can see every other Atom . Near or far . Instantly . And has ability to learn . Or percieve other Atoms . A self learning machine . Not needing interventions .

    Recently , computer science is trying to build AI .  A self learning machine . Not needing  interventions by humans . Or programming . This being the most efficient design . Needing the least effort . And a powerful god is also one that is most efficient . One that achieves the greatest results with the least effort .

    Such self learning machines are the creatures that you see . Evolving .
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    Post  Aristide on Wed Mar 20, 2019 7:46 pm

    Does anyone of you know the so called "Thorne-Żytkow-Objekt"?

    Its an amazing thing and extremly rare in the galaxy.

    In short, its a very massive Neutron star, which has sunken into the core of a red giant star. Basicly a star within a star. Because the neutron star in its core, such a star has a very high density and exotic matter is created inside it.

    The entire system would be quite unstable, because the neutron star would condense into a black hole, when enough matter collapsed on it.
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    Post  flamming_python on Thu Mar 21, 2019 1:55 am

    Aristide wrote:Does anyone of you know the so called "Thorne-Żytkow-Objekt"?

    Its an amazing thing and extremly rare in the galaxy.

    In short, its a very massive Neutron star, which has sunken into the core of a red giant star. Basicly a star within a star. Because the neutron star in its core, such a star has a very high density and exotic matter is created inside it.

    The entire system would be quite unstable, because the neutron star would condense into a black hole, when enough matter collapsed on it.

    Yes I have heard about it

    Another amazing thing is a quasi-star. None of them are around anymore, they were only present in the early universe.
    They had circumferences that would dwarf those of even the most massive stars known today. If placed in the Solar System, its orbit would extend out to beyond Neptune's.. over 7000 times the diameter of the Sun.
    But like the dinosaurs they died out. Reason is a conventional start cannot reach near those sizes; it's outer layers would begin to be blown away by intense solar winds and radiation.
    However quasi-stars were powered not by fusion but by black holes in the middle. They had very specific circumstances for their creation that were only valid when our universe was much younger and free of heavy elements.
    They would only last a few million years at most before the black hole would finish eating enough them from the inside; at which point the outward radiation pressure would collapse and what was left would implode into the black hole to complete its meal.
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    Post  GarryB on Thu Mar 21, 2019 10:56 am

    The problem with intelligent design, is first of all why did it take so long... we know of peoples and societies that existed more than 6,000 years ago so were they just figments of existence... just created as a record of a past that never actually happened... and if so... if you then create people whom you create fallible and able to lie and cheat, and then demand unbending faith, yet don't appear to each and every one of them to show your existence, but instead appear to very few and demand they convince the rest of us of your existence despite as I said making us capable of lying and indeed simply being wrong.... would that not be the very unfair... I mean we are generally talking about eternal damnation for not believing people about a being that made us all capable of lying and deceit for our own benefit..

    What sort of god would do this?

    They would not be testing our faith if we had nothing but the word of others that the god even exists, and with time passing and our own curiosity discovers things that clearly contradict what these few people god entrusted with his word have written... the earth is clearly not 6,000 years old or even 8,000 years old.

    Why did he not tell these people he appeared to and got them to write things down some things he knew about the universe that were not common knowledge then so we could work out for ourselves that the people who wrote the bible were in touch with a higher power that knew things they could not possibly know back then... like a 100% accurate drawing of the far side of the moon.... drawn in 50 AD. or something.
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    Post  kvs on Sun Apr 21, 2019 7:45 pm



    Nice skeptic talk on General Relativity.    But he is overly fixated on the one-mass "problem".   It is possible to solve
    for N masses in GR, but it is a numerical nightmare.   It is vastly easier to solve the Navier-Stokes fluid partial differential
    equations than the GR partial differential equations.  

    Whatever that is observed and called "black holes" cannot be described by GR.   All so-called black hole solutions of the
    Einstein equations are obtained by setting the right hand side (the stress-energy source tensor) to zero.   This is not
    any sort of mathematical solution method for the equations with a non-zero source term.   It is the solution of the homogenous,
    source-free equations.  

    When you solve the GR equations with zero source term you get two solutions: 1) the flat Minkoswski space-time and 2)
    the solution claimed to be "forced by a point mass singularity".   Solution (2) is actually a set of four possibilities depending
    on how you choose the sign (note that the metric terms are all quadratic so that both + and - solutions for every term
    are valid mathematically).    The basic structure consists of a finite bubble space time (with a "radius" corresponding to
    the Schwarzschild radius) imbedded in a semi-infinite shell that becomes Minkowski flat as r -> infinity.   The contact surface
    between these two space-times is the "event horizon".   GR adherents cherry pick the signs of the metric terms to describe
    geodesics (world lines) supposedly entering from outside the event horizon and moving to r = 0.   That is cute, but recall
    that there is no point mass at r = 0 since the solution is for the homogeneous problem.    

    There is no free lunch in life and in mathematics.   It is absurd to solve for the homogeneous solution of a nonlinear
    and linear set of equations and then cut and paste in a source term.  You have to solve for the source term problem which
    does not follow the same algebraic solution path or numerical solution path.    This is basic high school mathematics.    
    There is no "advanced math" that avoids this fact.  

    So what we really have physically, is a repulsive space-time bubble squeezing out the exterior space time and deforming it
    away from Minkowski flatness.   Thus, outside the event horizon, it has the curvature as if a mass was distributed inside the
    horizon.   Geodesics cannot cross the event horizon as envisioned by the fake homogeneous black hole worshippers.   Some
    infinitesimal test mass released inside the horizon would fall towards the horizon, just as such a test mass falls towards it
    when released outside the event horizon.    The only way to have this "black hole" solution is from quantum noise in a big
    bang scenario where microscopic space-time irregularities grow into macroscopic space-time structures.    There is no
    stellar collapse process that gives you this particular homogeneous solution of the GR equations.    

    If you look over the research purporting to demonstrate stellar collapse into black holes, you see pseudo-math voodoo where
    the homogeneous solution is used as the background state.   There are not explicit solutions starting from a compact mass
    distribution and time-stepped towards the formation of a horizon.   Until the day that such solutions are produced, the
    "fact" of stellar collapse into black holes cannot be assumed to be a fact.   It is just a hypothesis based on dubious mathematics.

    I am sure that the recent, enhanced image supposedly showing a black hole will be trotted out as proof that GR is right.  That
    would be utter BS.    Galaxies are not stress-energy tensor zero systems.    What we are observing requires a different set of
    equations to model since GR has not actually been shown to produce such results.   If this is too kooky for some, well that
    is life.   The gravity aspect of GR is purely derived from Newton's theory.    The principle of equivalence and the principle of
    general covariance do not say anything about the laws governing gravitation.   So GR was obtained by fitting to Newton's
    theory in the weak field limit.   The problem with this is approach is that we also need to know the behaviour of gravity in the
    strong field limit.   It is not physical to extrapolate the strong field limit from the weak field limit.   So there is no reason for
    GR to even get gravity near massive objects right.
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    Post  kvs on Mon Apr 22, 2019 2:06 am

    BTW here is a paper (peer reviewed) that actually does specify a non-zero stress-energy tensor and solves the GR equations
    for a point mass source:

    http://www.m-hikari.com/astp/astp2007/astp1-4-2007/castroASTP1-4-2007.pdf

    Note that this proper solution cannot be mapped to the homogeneous solutions of the past claimed to be point mass solutions.

    Physics is in a really sad state when group-think "proof by authority" BS is accepted as established truth.

    The one good thing is that none of the facile BS being fed to the masses by the so-called physics gurus is worth much and there is a whole
    universe of discovery that remains open.


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