Simple proof against absolute space and time
I've seen various 'proofs' of both relative and absolute time, but none of them seemed valid. I suppose mine here is similarly invalid, but I cannot identify the flaw in it.
Under absolute spacetime, all events are objectively ordered and all motion is absolute, not relative. A typical view that asserts this is the original Lorentz Ether theory which posited a preferred foliation, but not a preferred moment in time. neo-LET has evolved over the last century and usually adds the preferred moment to this, but that's unimportant.
The proof is simple:
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There is no coordinate system that foliates all of spacetime, and any objective view of spacetime requires such a coordinate system. Therefore such views are self-inconsistent. That's it.
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For example, the current inertial frame of Earth won't do: There are objects beyond our event horizon (events from which light can never reach us even in infinite time). If such objects existed in our inertial frame, light from them would reach us in finite time, so these objects don't exist in that frame, and thus the frame doesn't foliate all of spacetime.
The usual selection among absolutists is the comoving frame which is a curved frame which locally corresponds to the inertial frame in which the CMB appears isotropic. In that frame, two clocks separated by arbitrarily large distance can in principle be synced despite the inability to send signals between them. It is X many seconds since the big bang. It is the only coordinate system I know that doesn't require a preferred location. Motion is absolute in this foliation, and our 'absolute' velocity is called 'peculiar velocity' in physics, and currently happens to be around 375 km/sec for our solar system. It will be more than twice that in 100 million years.
That coordinate system works great for large distances, but completely fails where there is large curvature of spacetime: black holes. Any such non-local foliation does not cover the events within the black hole, and thus do not constitute a foliation of all spacetime. So say Fred falls into a black hole at time X on his watch, and he knows the mass of the thing and currently it is 5 minutes past X on his watch. What time is it actually? The watch measures proper time of Fred's worldline, not absolute time. The question is unanswerable given this coordinate system, and under an absolute interpretation of spacetime, there must be an answer to such a question.
Something like a Kruskal-Szekeres diagram sort of foliates spacetime containing a single black hole, but it fails on any others, and like the inertial frame, does not foliate events too distant to be causally connected ever.
Under absolute spacetime, all events are objectively ordered and all motion is absolute, not relative. A typical view that asserts this is the original Lorentz Ether theory which posited a preferred foliation, but not a preferred moment in time. neo-LET has evolved over the last century and usually adds the preferred moment to this, but that's unimportant.
The proof is simple:
- - -
There is no coordinate system that foliates all of spacetime, and any objective view of spacetime requires such a coordinate system. Therefore such views are self-inconsistent. That's it.
- - -
For example, the current inertial frame of Earth won't do: There are objects beyond our event horizon (events from which light can never reach us even in infinite time). If such objects existed in our inertial frame, light from them would reach us in finite time, so these objects don't exist in that frame, and thus the frame doesn't foliate all of spacetime.
The usual selection among absolutists is the comoving frame which is a curved frame which locally corresponds to the inertial frame in which the CMB appears isotropic. In that frame, two clocks separated by arbitrarily large distance can in principle be synced despite the inability to send signals between them. It is X many seconds since the big bang. It is the only coordinate system I know that doesn't require a preferred location. Motion is absolute in this foliation, and our 'absolute' velocity is called 'peculiar velocity' in physics, and currently happens to be around 375 km/sec for our solar system. It will be more than twice that in 100 million years.
That coordinate system works great for large distances, but completely fails where there is large curvature of spacetime: black holes. Any such non-local foliation does not cover the events within the black hole, and thus do not constitute a foliation of all spacetime. So say Fred falls into a black hole at time X on his watch, and he knows the mass of the thing and currently it is 5 minutes past X on his watch. What time is it actually? The watch measures proper time of Fred's worldline, not absolute time. The question is unanswerable given this coordinate system, and under an absolute interpretation of spacetime, there must be an answer to such a question.
Something like a Kruskal-Szekeres diagram sort of foliates spacetime containing a single black hole, but it fails on any others, and like the inertial frame, does not foliate events too distant to be causally connected ever.
Comments (49)
As you can see, any event can be located in an inertial frame, but only those events within our past light cone can be detected by us now. Events outside that cone are still in the reference frame but cannot influence us.
Gravitation can't be accurately described by inertial frames but require curvilinear coordinate systems.
I don't get this. Why would they have to reach us? The light will never reach us because of cosmic expansion whether they exist or not, so the fact that we don't see them doesn't mean they don't exist.
Quoting noAxioms
I'm not sure about that. As far as I know, any spacetime that doesn't allow for closed timelike curves is open to being sliced into global hypersurfaces so they should be allowed in universes with black holes. At least, all the discussions I've seen about the idea of an absolute present in GR seem to mention closed timelike curves as being problematic for the concept, but nothing about black holes precluding them.
In other words, time travel is problematic for presentism (who knew right?), so it would be a problem for them if we lived in a world where time travel is possible, but I don't think they should lose sleep over their possibility since closed timelike curves have a number of other wild consequences to them (such as retrocausality) which make their existence unlikely.
I've been in discussion about this on physics sites, but they don't care so much there about the metaphysical implications to absolute time interpretations.
Quoting Kenosha Kid
You've drawn flat Minkowski spacetime (with arbitrary inertial frame) in which light from any spatial location will reach any other location. That makes it an inappropriate model of the large scale universe where light that is currently say 17 GLY away will never get here, not in 17 billion years or ever.
Earth has an event horizon, and Minkowski spacetime does not. The universe cannot be foliated with such a coordinate system.
Quoting Kenosha KidYou can still foliate reasonable gravitation in 'bent' Minkowski spacetime, but not black holes. So for instance, a device measuring absolute time here on Earth would run apparently faster than one on the surface of Saturn due to the lower gravitational potential here on Earth. The same device on a ship with relativistic absolute speed would similarly appear to run faster (than the clock next to it) than it would if the ship had low peculiar velocity.
Quoting Mr BeeThere's no requirement for light to reach any location from any other since there are very much cases where that does not occur. My point was that in an inertial frame, light can reach location X from Y given enough time, and thus such a model is not a model of our universe.
If there is a boundary to an inertial frame, then event outside that boundary do not exist in that frame. An inertial frame does support cosmic expansion, but it does not support acceleration of that expansion. So given no such acceleration, there would be no event horizon and light will eventually get from location X to Y given time. And even locally, an inertial frame cannot foliate the interior of black holes, so it fails twice.
There are indeed ways to do it with a single black hole, but you must assume the black hole is at some kind of privileged location. So consider 3 events: A clock is dropped into a black hole. Event A is that clock 1 second (measured on that clock) after passing the event horizon. The black hole is big enough that it survives at least one second. The rock is dropped from a hovering location outside, which shines light down on the dropped clock. At some point the last light is emitted from this location that will catch up to the dropped clock before it hits the singularity. Event B is that hovering location 1 second after that last light goes out.
Event C is at the location of the former black hole after it has evaporated.
Yes, you can come up with various schemes to order these three events, but do any of those schemes order all of spacetime? OK, C occurs after B since it is in the future light cone of B. That's easy. Not so easy with event A.
I'm not suggesting retrocausality anywhere. Event A is not causally connected with either B or C, so no objective ordering scheme is going to produce a contradiction unless B is in A's future but C is in A's past.
noAxioms!
Two quick questions:
1. Does black hole time travel increase or decrease Time ( I can't remember)?
2. Do black holes contribute to Multiverse theories at all?
It's perfectly appropriate for that: that's just light further outside the light cone. It being further away just means its further away. Minkowski spacetime is not appropriate for gravity, though.
Quoting noAxioms
Not sure what you mean. Never heard of 'bent' Minkowski spacetime or anything in which that would make sense. Minkowski spacetime is, as you said, flat.
Quoting noAxioms
Is this what you mean? Well, this is exactly how you do GR in practise: you treat, at any given event, the spacetime as that of SR. That was Einstein's devised approximation.
Quoting 3017amen
Black holes slow down time, right to a standstill at the singularity.
Quoting 3017amen
Yes, Smolin's multiverse theory, also once forwarded by Hawking, is that black holes are baby universe that inherit laws of physics from the parent universe. This is cosmological Darwinism.
I don't see how that is a consequence of a global inertial frame. Light may not reach us for other reasons unrelated to it, one possibility being the cosmic expansion of the universe being faster than light.
Quoting noAxioms
You seem to be mixing up the boundary of the observable universe with the "boundary" of an inertial frame, the latter of which I don't really understand. They are both not the same.
Quoting noAxioms
I don't really have the expertise to properly address this (hopefully someone like @Kenosha Kid can chime in here and give his input). My understanding is that it is mainly spacetimes with closed timelike curves that preclude the existence of global hypersurfaces, but I haven't heard anything about black holes doing the same.
Time slows (is more dilated) when deep in a gravity well, So clocks on Earth for instance run objectively slower than say GPS clocks (which are very high up and not moving fast). Those GPS clocks are slowed due to their orbital motion, but the gravity effect is greater at that altitude. Clocks on the ISS run slower than the ones on the ground due to minimal gravitational potential difference in low orbit, coupled with significant dilation from the higher orbital velocity. So at an altitude of 1.5 R (R being Earth's radius), the two effects cancel out and orbiting clocks can be synced indefinitely with those on the ground.
Similarly, from the PoV of the distant observer, a clock falling into a black hole freezes on the event horizon. It doesn't just appear to freeze. Coordinate time slows and actually stops there.
From the PoV of the observer falling in, he sails right in without a hitch, and the universe behind him appears to speed up, but not infinitely so. There's definitely a time outside the black hole beyond which is not part of his past light cone, and thus is not observable.
About the multiverse thing, I think there are theories that a black hole in one universe is a white hole from the perspective of the interior spacetime. I think we're possibly supposed to be in such a white hole in some of these theories, except I don't see how we could be expanding then. There's no singularity (big crunch) at the end of time like one would expect from a geometry with an abrupt cessation of time like that.
I got lost at:
Quoting noAxioms
It's not clear what frame of reference we're in here. From the perspective of an observer outside the event horizon (with some magic blackholescope), the clock will accelerate toward the singularity and run slower and slower. Any photons emitted from the rock (which is getting further and further away from the clock) will still travel at the speed of light and catch up with the clock, because the clock cannot move at the speed of light. Effectively, there will be a time at the singularity in which no more photons can hit the clock because the clock has no future. From this perspective, the clock is part of the singularity at this point.
From the rest frame of the clock, it is in perpetual free fall. Eventually the rock will simply recede so far into the distance it cannot be detected. The limit of this is an event horizon for the rock after which no more new light can reach the clock. However! If we call Event A the first photon emitted that will reach the clock and Event B the last photon emitted by the rock that can reach the clock, there is still light emitted between A and B that the clock has not yet "seen". So the light ought to get dimmer and ever redshifted, but should never stop. The last photon emitted by the rock that the clock will ever see must be when the clock has no future, which is, in the clock's rest frame, at t=infinity.
You don't comprehend my explanation, so I'll try to comprehend your vision.
Perhaps you can explain a distant galaxy then using this coordinate system. Gravity at very large scales is negligible, so space is effectively flat so long as we're not noticing lensing effects and such.
So take GN-z11, a very distant thing with redshift of over 11.
Using your coordinate system, where (and when) is the event when the light was emitted that we see of it today? The wiki site says it was emitted 13.4 billion years ago, but it could not have got far enough away in only 400M years for light to take that long. Of course, wiki isn't using inertial coordinates when making that statement, so kindly describe the situation in those terms. Where is the emission event? If it vanishes today, will we ever see that from here if we wait long enough?
Quoting Mr BeeThere is no cosmic expansion under inertial spacetime. There is only an explosion of stuff from a point, with nothing moving at faster than c.
They are indeed not the same. The boundary of our inertial frame is much less than the 47 BLY radius of the observerable universe, and even less than the ~16 BLY distance to the event horizon. The current radius of our inertial frame must be 13.8 BLY because nothing outside that radius could have come from the big bang without moving faster than c, and nothing moves faster than c in an inertial frame.
Your understanding here is fine. Nobody is proposing a closed timelike curve. Any foliation, objective or not, would preclude that.
Quoting Kenosha KidFirst of all, I meant dropping a clock, which seem more useful than dropping a glowing rock. I used a rock at first and neglected to change them all to 'clock'. But it moves like the rock: not under propulsion or anything.
The light shines from the hovering station. It can be light from the clock displaying the time if you will. The time is the proper time of the hovering space station that maintains a constant distance from the black hole. We can build a shell around if you like it so we don't need to expend fuel to stay indefinitely at that location.
I've caused confusion. The rock and the dropped clock are the same thing. The space station can watch it fall in, but if it reads time T when it crosses the event horizon, then the space station will never see the clock read anything after T. It will appear from the space station to slow and approach but never reach T. Event B is that clock when it reads T+1.
Again, they are the same thing, so the clock indeed will eventually reach the abrupt end of time and tick it's last, so to speak. This is assuming the clock is a point device that isn't destroyed by excessive violence like tidal forces before it gets to the singularity.
If you want to describe a clock and a rock dropped say at separate times, you need to lay out the scenario. I never meant for there to be two things falling like that.
As No Axioms already explained, relativity tells us that extreme gravitational wells like black holes will severely dilate time (if you've ever seen the movie Interstellar, they cover this reasonably well with the extreme time dilation experienced on the "water world" planet they first visit, close to the black hole Gargantua)- we can and have even measured this in less extreme cases, like in Earth orbit, and indeed GPS satellites would quickly cease to operate effectively if this was not accounted + corrected for. So time "runs slower" in such a gravitational field. To an outside observer, an astronaut falling into a black hole moves increasingly slowly... until they appear to freeze entirely at the event horizon.
Worse, at the event horizon, time dilation becomes so extremely that, from the perspective of the outside observer, events there do not ever occur- not even after an infinite amount of time has passed. They are dilated infinitely far into the future. So from the perspective of the outside observer the infalling astronaut never actually crossed the event horizon (although from the astronaut's perspective they certainly do- though they don't necessarily notice anything special when they cross the point of no return), and events inside the black hole cannot be consistently assigned a spot on any outside observers timeline: those events are dilated infinitely distant into the future- they never occur, from the perspective of those outside of it, even after an infinite amount of time has elapsed. But of course to those inside, these events are very real: including/especially the astronauts inevitable demise inside the black hole!
And I'm not sure that black holes directly imply any multiverse theories, the way that e.g. a geometrically flat, infinitely extended (spatially) universe implies a cosmological multiverse, or some interpretations of QM imply a quantum multiverse. But black holes do figure prominently into at least some "multiverse(ish)" hypotheses, like Smolin's cosmological natural selection hypothesis where "baby" universes are spawned within black holes (and so you get this nested hierarchy of universes within universes and so on). It is at least highly intriguing that the only place where conditions approach those of the early (Big Bang) universe are the interiors of black holes, and maybe even moreso the fact that a time-reversed black hole (i.e. a white hole) looks eerily similar to the Big Bang itself.
Right. So, first, there was a supposed stupendous inflation period in the early universe that cannot be described by any inertial frame. Second, it is unexpected that the galaxy would have formed 400M years after the big bang, i.e. it is a cosmological and astronomical mystery but a) that doesn't stop it being 13.4 billion light years away from us when it did form and b) such a mystery can be a sign of an incomplete or faulty model. Cosmology is still in its infancy and while recent successes like gravity wave detection and the black hole image speak well of the underlying theory (general relativity), it is likely that the cosmological model has some kinks to work out yet.
One possibility is that there exist some regions where inflation carried on a lot longer than others. A longer period of inflation between us and GN-z11, for instance, might explain why it could have formed less than 13.4B LY away from us but still appear 13.4B years old. Or maybe it turns out 400M years is long enough to start making galaxies. I'm sure the answer will be profound.
Quoting noAxioms
I understand, I think. There are two related effects going on here, and I was referring to the first with my magic blackholescope: from the observer's point of view, time slows down for the clock the faster it moves due to the BH's gravitational pull; light emitted from the clock is also redshifted by gravity.
So it is true to say that, if the clock were a regular emitter for instance, light from the clock would reach the observer ever more slowly. And it is also true to say that no more light will reach the observer once the clock passes the event horizon. But the second is not a continuation of the first because the clock will still have a subluminal velocity even at the event horizon, therefore its time will not have slowed to a standstill. Rather, the light from the clock is redshifted to zero frequency at the event horizon. The light will appear redder, go through infrared, then microwave, then radiowave frequency bands then, at the horizon, will disappear.
In you all's learn-ed opinion, since science namely theoretical physics, seem to be split on what existence was like before the Big Bang, could multiverse theories be an attempt to explain causation prior to the Big Bang?
Because multiverse theories cannot be falsified, I realize that it seems the floodgates tend to open-up allowing for all sorts of radical ideas. I'm in the process of studying this a bit more, and was also wondering how it could possibly square with the concept of eternity, Platonism, and unchanging timelessness.
As a very rudimentary example, what in theory, would exist outside of the block universe?
You have to be careful distinguishing different types of multiverses, since what is true of one isn't necessarily true of the other- they are posited in different contexts and for different motivations (i.e. to address different types of problems/concerns, or to explain different kinds of observations) and can be structured entirely differently from one another (i.e. how the different universes relate or exist relative to one another- do they just precede one another in time? Do they exist alongside one another but are causally disconnected? etc.). Cyclical cosmologies (at least a few of which can be characterized as "multiverses")- where the expansionary phase of the universe is follow by a contracting phase which is in turn follow by an expansionary phase and so on- can and do speak to a pre-Big Bang epoch- and the removal of the hypothetical t=0 singularity is considered a feature of loop quantum cosmology (and hopefully other candidates for a successful quantum theory of gravity).
Its also not the case that multiverse theories are generically untestable or unfalsifiable. Some of them certainly seem to be, others not, and this differs from case to case in the same way multiverse theories themselves differ (i.e. as mentioned above). So its difficult to talk about "multiverse theories" in general with any accuracy, since they don't have all that much in common once you get into the details. Have to be sure to specify what flavor of multiverse you have in mind.
OK, you're allowed to give it more time, but how long do you want? It's going to take 13.4 billion years to get far enough away, at which point there's no time left to send the light back to us here.
Actually it does stop it. It's not a mystery, it's a physical impossibility in an inertial coordinate system for something to move 13.4 BLY away and then send a signal back, all in 13.8 BYr. Waving your hand around and spreading 'I don't know/it's a mystery' dust all over the place isn't a viable model.
I take it you're not familiar with the comoving coordinate system (which does foliate spacetime to any distance) or the FRW models of the universe (from which that 13.4 BY figure comes). I'm not here to debate the viability of an inertial coordinate system to describe the universe. Trust me, it isn't a candidate. I'm here to discuss my argument against absolute time, with people who know their physics sufficiently to comment productively on it. This is not that discussion.
There are at least six kinds of multiverses discussed. Tegmark enumerated them as Level 1 (other Hubble spheres), Level 2 (other bubbles in eternal inflation theory), Level 3 (other quantum worlds), and Level 4 (other unrelated structures). There is also the Smolin evolutionary thing where the interiors of black holes are considered to be other universes. If Level 1 is our universe but spatially 'not here', then there should be a Level 0 which is our universe but temporally 'not now'. That's six at least.
Of those, it is probably the Level 2 multiverse that most qualifies as an attempt to explain causation of the Big Bang. It is also the model that explains the fine-tuning argument.
The Smolin evolutionary thing also seems to attempt this, but each universe created is of infinitesimal magnitude (matter and energy and such) compared to its parent, so it's hard to see how that can continue for enough generations for evolution to be effective.
Whether it is interpreted as block or not seems immaterial. Look into eternal inflation theory. Wiki has a terse entry on it. I found a more comprehensive description in Tegmark's Mathematical Universe with some illustrations that help with visualization. There are other 'universes' that have different number of spatial and temporal dimensions, and the vast majority of them cannot produce complex physical states.
I need your opinion then. OK a foliation based on the perspective some outside observer cannot account for events beyond the event horizon, and thus seems to not to be a viable candidate for an objective foliation of all of spactime. Is there some other coordinate system that is actually up to the task? If not, is this a valid falsification of objective space and time such as is proposed by Lorentz Ether Theory? This is not even including those interpretations that additionally posit a preferred moment in time.
So you drop an absolutist into a black hole, then ask him, what's your brother doing now? His inability to give a coherent answer seems to falsify his view, but then until we drop him in like that, I suppose he's free to deny the interior events altogether, which seems to be the only recourse.
I don't see why an absolute coordinate system would be obligated to propagate that the speed of light. Hence, those events that are beyond our event horizon nevertheless might have a particular position in an absolute coordinate system.
The answer to your question seems to me to be that any coordinate system might be set up as absolute; relativistic physics specifies how we translate from any frame to any other frame, so calling any frame of reference absolute becomes simply irrelevant.
Yeah I would assume that the extreme time dilation in the vicinity of a black hole- culminating in the infinite time dilation at the event horizon itself (and the absolutely off-the-wall implications that carries)- would be very problematic for any form of absolutist wrt spacetime... but then I'm not familiar with this debate (absolutism vs. relationism) outside of Smolin's discussion in the context of his cosmological natural selection (which was largely historical in nature), and I would have assumed that relativity in general made any sort of absolutism about spacetime a non-starter and more or less settled the matter..
but as that is evidently not the case (if the philosophical debate persists to this day), I think I must be missing quite a few of the relevant issues. I'm actually reading the Stanford entry on this right now, to get a bit more background on this particular dispute.
Light in an inertial coordinate system can get from any location to any other in a time dependent on the separation of the two locations. This does not describe our actual universe.
They do in some coordinate systems, but they don't have a particular position in our inertial frame.
No coordinate system works. That's been my point. Every choice leaves parts of spacetime unordered. As Enai puts it: There are always events that cannot be consistently assigned a spot on any choice of objective timeline.
Indeed; that is exactly my point.
Quoting noAxioms
Quoting Enai De A Lukal
These are not the same.
Not literally, sure, but I think the upshot is the same: if the events at/beneath the event horizon do not ever occur from the perspective of the outside universe, any timeline including those events will be inconsistent with that of the outside universe. But any timeline not including those events will be inconsistent with that of e.g. the infalling astronaut- from their perspective, they most definitely cross the event horizon, and go on to meet whatever unpleasant fate awaits them within the black hole (probably being turned into a human spaghetti-noodle).
But so this is why- from my admittedly extremely limited/rough understanding of this debate- its hard to see how this isn't fatal for any "absolutist" notion of spacetime: what is absolute here, if there are collections of events (black holes) that do not ever occur from the perspective of the outside universe, and no self-consistent timeline that includes them both?
If someone outside the hole applies the appropriate transformations to their forever-falling astronaut, they will find that form the astronaut's perspective the fall is finite.
If the astronaut applies the appropriate transformation, they will find that for someone outside the hole the fall takes forever - or more.
I don't see any inconsistency. What did I miss?
Quoting noAxioms
I do not see that this has been shown.
That is a limitation of inertial frames, not of the physical universe. Also, you seem to think that if we see light from a star 13.4B LY away, there must have been a time when that star was very close to us. That is not right. It didn't have to "move 13.4 BLY away and then send a signal back". Stars did not emerge from the big bang.
Quoting noAxioms
You mean pretend physics, which requires a pretend physicist to discuss it with? Fair point, I am not that person. Gimme a holler if you need someone who taught relativity at university though. I'm sure it won't measure up to pretend physics but it has its place.
My experience is that slicing is not precluded. It depends on the origin of reference frame. If it's outside the event horizon, you can still slice, but if the slice intersects the horizon you have to treat the exterior and interior separately. This isn't particular to slicing. Spherically symmetric slicing for some model black holes with the origin inside the horizon have also been shown to work.
Good to know, thanks. Again it's nice having an expert around to keep us philosophers in check :smile: .
I'm not particularly an expert on GR (my field was QM), so you oughtn't to assume an overriding authority from me. However I know enough to have lectured a syllabus and have an interest in it.
This question seems based on an error. It's worth reiterating though that the problems expressed here are not physical problems. The Einstein equations are notoriously difficult to solve exactly (there are only a handful of known exact solutions) and, as I said earlier, the easiest way to solve them is to treat spacetime as a series of locally flat spacetimes (slicing or threading). As with any such approximation, this brings with it certain problems (e.g. sensitivity to initial conditions not captured by the initial inertial frame) and has certain limits (where spacetime cannot be shown to asymptotically approach flat spacetime, such as at the centre of a black hole). Black holes are not features of special relativity, only exact GR.
So there is little profundity to be found from these problems. They have to be overcome not to get a better idea of spacetime directly, but to numerically solve approximations to the Einstein equation and (hopefully) gain insight about spacetime that way, i.e. they are pragmatic only*. Any generalisation about these problems to the physical universe is seriously flawed.
*They are more important to quantum gravity because SR is the only feasible consistent way of describing Einsteinian gravity (as opposed to e.g. gravitons) quantum mechanically. But, still, this is a practical problem rather than a fundamental mystery of the universe.
He cannot apply the transformation, which is what is meant by events that cannot be consistently assigned a spot on the outside observer's timeline. His events do not exist at all on that outside timeline.
Quoting Kenosha KidExactly, which is why I say that inertial frames do not describe the universe.
The material/energy from which they are comprised very much did.
Cosmologists estimate that the light we see now from GN-z11 was emitted when the universe was around 0.4 BY old, and was emitted at a proper distance from here of about 2.8 BLY at the time, which is closer than the emission distance of other galaxies with somewhat lower redshift. Light from a galaxy with redshift z=2 for instance was emitted at a proper distance of around 5.8 BLY away. That has the unintuitive effect that the more distant galaxy (the one receding faster) appears larger (greater angular measure) than a similar size object that is closer. Were the same two objects to be viewed in a Minkowski inertial universe, the angular measure of the higher redshift object would be smaller.
Yes, that's true. But when we gaze at a galaxy 13.4B LY away, we are not seeing the material and energy that would later form that galaxy, we are seeing the formed galaxy. Ergo the galaxy did not form close to us then "move" 13.4B LY away from us. It was 13.4B LY away from us when it emitted the light we are seeing now.
Quoting noAxioms
For sure, LETs can't describe black holes. There's no aether definable at or within the event horizon, although people have tried. You don't need to foliate spacetime to get to this conclusion, nor consider events outside the light-cone as being outside the entire reference frame. Black holes are curvatures of spacetime, i.e. assuming they exist is assuming your conclusion. The natural questions would be: what is the closest thing to a black hole in LET (the static aether), and is it consistent with empirical evidence?
So acceleration is equivalent to gravity, so our space station hovering at 1g outside the black hole can be equivalent to the Rindler scenario where there is only acceleration and no significant mass/gravity anywhere in flat Minkowski spacetime, which can be described using SR rules.
So consider a coordinate system of a long rigid spaceship with meter markings on the sides that acts as our coordinate system. At the origin (the place marked zero), it is accelerating at a continuous 1g. Does this ship's coordinate system map all of spacetime? No, it does not. Acceleration of the ship is greater the further 'down' the length you go, until a limit is reached (about a lightyear from the origin in this case) at the event horizon (called the Rindler horizon).The ship cannot extend further back than this, but in can extend indefinitely in the 'up' direction. A clock dropped from the origin will fall past the ship and appear to freeze as it approaches that event horizon in the coordinate space of the ship. Light from events beyond this horizon can never reach any part of the ship, which means that while I accelerate at 1g, light from about a light year away will never reach me.
The events beyond that horizon do not exist (cannot be meaningfully ordered) in the coordinate space of the ship, and thus there exists no transform between them. Events there cannot be meaningfully placed on the timeline of the ship.
Of course, in the frame of the dropped clock, the rear of the ship passes it by without notice and the clock ticks on. Now from the perspective of the clock beyond the ship's event horizon, there is no event horizon at all. It is merely a coordinate singularity and not a physical singularity. Similarly, a black hole event horizon is a coordinate singularity. That means that from the perspective of beyond the horizon (the falling clock), the space on either side of the horizon can be mapped in a coherent coordinate system (that of the falling clock in this case). So there does exist a mapping between 'inside' and 'outside' so to speak, at least in the Rindler case, but only relative to an inertial (falling) reference. There is no physical singularity in the acceleration scenario, and there is one in the black hole case, and also there's the fact that no object can be falling into more than one black hole, so there seems to be no coordinate system that maps more than one of them.
What?
Let me put it this way:
P1 Time is absolute. There is an absolute ordering of all events in all of spacetime.
C1: For any event in spacetime and a given (time-like, or at least not space-like) worldline, that event is simultaneous with exactly one event on the given worldline.
C2: If, from the perspective of any particular observer, the simultaneity of two events does not correspond to C1, then that perspective does not correspond with reality. It is merely an abstract perspective.
Notice that it isn't necessary for any observer to be aware of this absolute time. We're just supposing there is one, not that it can be known for sure. Problem is, no coordinate system I can think of meets the requirement of C1, and the lack of the existence of such a coordinate system contradicts P1.
My choice of the first event is the falling clock when it reads 1 second beyond what it did as it crossed the event horizon. The first worldline is the clock hovering near that black hole, and a second worldline is a different clock falling into a different black hole.
How might one assign a time that is simultaneous with that first event on each of those two worldlines. The coordinate transformations you speak of seem not to exist, and at best they only transform between an abstract relation to the one actual one. I don't see the purpose of considering the abstract one at all.
Can you unpack this? The Rindler horizon can be reached one of two ways. As the worldline of a body undergoing acceleration, it is reached as that acceleration becomes infinite. This is the light-line (e.g. photon creation). As the proper time of a body undergoing proper acceleration, it is reached at eternity.
Why is your apparently infinitely long ship accelerating more the further away from x=0 you go? And why do you think it is infinitely accelerating one LY from x=0?
Sorry, I'm unfamiliar with that term. Google was no help.
Acceleration must be greater further 'down'. Less in the 'up' direction, so the 'ship' can be as long in that direction as required to serve its purpose as a coordinate system for an accelerated reference frame. It is somewhat equivalent to my weight being greater on the ground floor of a building than it is at a higher floor. Clocks run faster in the higher low-acceleration portions of the object than the clocks in higher-acceleration locations further down.
The product of the distance to the horizon and the inverse acceleration will equal c^2. So c^2 / 9.8m/sec^2 = ~9.2e15 meters which is not quite a light year.
You brought up Rindler coordinates. There are two interpretations of these. The original is that they map the hyperbolic worldlines of accelerating bodies in an inertial frame. The second is that they map the length contraction of accelerating bodies in the bodies' non-inertial frames.
In the former, the Rindler horizon is the Minkowski worldline of a body with infinite acceleration, making it light-like, whereas in the latter it is the coordinate approached by an accelerating body as t goes to infinity. Either way, it's not something you can reach in a finite amount of time and with a finite amount of acceleration.
Quoting noAxioms
Actually it isn't. All accelerations lead to the horizon at eternity. None reach it in real time except, as said, infinite accelerations. How quickly they approach the horizon does depend on the acceleration, yes: x = 1/a.
Quoting noAxioms
Nope, still not getting you. The only thing I can think is that this is a ship that is linear after Rindler transformation, i.e. that the coordinate x here is 1/a. Is that what you mean? I don't think this proves anything. It's effectively saying that after an eternity of travelling along the ship, the bit of the ship you're at will have reached its maximum acceleration and be at the horizon. Anything beyond that is unreachable purely from the fact that you can't reach, let alone pass, eternity. But that's just because your coordinate means the inverse of acceleration, not an actual event in spacetime.
Thus I don't know what you mean by the wording here:You have links where this wording is used? I'm trying to make sense of it.
You cannot, by definition, "accelerate away from the Rindler horizon". That horizon is an acceleration limit. Lemme dig out a pic to explain.
X here is position, T time in a Minkowski frame. The hyperbola are worldlines of bodies undergoing constant proper acceleration. t here is the proper time of the accelerating body.
As the body is accelerated for longer and longer, T and t increase. At infinity, all worldlines converge at the Rindler horizon, i.e. they have maximal velocity and converge to the worldline of infinite acceleration (the light-line).
So it's difficult to make sense of what you're saying. I get that you're trying to simulate gravity here. If you have a long ship pointed radially outward from a black hole, the bottom undergoes more acceleration than the top. I can't envisage, in the absence of gravity, how you can make a single object do the same. Perhaps a fleet of ships would be better. Non-rigid bodies were among the original hypothetical objects of the equivalence principle for this very reason.
It is not. It, like any other event horizon, is a boundary in spacetime separating events that can have a causal effect on a given worldline and those events that cannot. So there is an event horizon currently about 16 billion light years distant beyond which no event can ever have a causal effect on Earth (the worldline in question here). This is due to the acceleration of Earth away from locations more distant than that. The only reason that is technically not a Rindler horizon is that Earth's acceleration is not constant, but is instead increasing.
And you choose a picture correctly showing the worldline of our observer at X=1 (assuming we choose units where ? is 1), curving to the right (positive acceleration AWAY from the Rindler horizon to the left at X=0. The text accurately says "If the observer is located at time T = 0 at position X = 1/? (with ? as the constant proper acceleration measured by a comoving accelerometer), then the hyperbolic coordinates are often called Rindler coordinates with the corresponding Rindler metric."
X = 1/? (a positive location). ? is positive, so acceleration is away from location X=0 where the Rindler horizon is. Your post contradicts your own assertions.
The picture depicts the Rindler coordinates of one body, one worldline. Yes, other bodies to the left and right, at different accelerations, would trace those other worldlines, but their times would not correspond to the times plotted for the one object at X = proper distance of 1. The t= values are for that body and are not shown for any of the other worldlines.
After any amount of time, the proper distance between our accelerating body and the Rindler horizon remains 1. It is a constant. Sure, if you choose an inertial frame where this whole setup is moving fast, you can length contract it down to any size you like, but you don't need to wait a long time for that. Just choose a different frame. From the perspective of our constantly accelerating observer, the horizon remains at a fixed distance behind him (in the direction opposite his acceleration vector).
You are unaware of acceleration not being constant along the length of an accelerating rigid object? This is a simple consequence of special relativity. Read up on Bell's paradox (the two ships accelerating while attached by string). It illustrates most of the concepts involved.
And connect them with string, yes. Unfortunately, the clock of only one of those ships will correspond to the times depicted in the picture above.
Follow that worldline to the edge of the diagram. Now, tell me, is it closer to the horizon or further away? Yes, the worldline is bending to the right (increasing X). But the horizon is always moving to the right more quickly, except at eternity where all worldlines are parallel. Glad you see the relevance of worldlines now though.
Quoting noAxioms
The Rindler horizon is not X=0. X=0 lies on the horizon at T=0.
Quoting noAxioms
So what you mean is that we choose a frame of reference where the acceleration is not simultaneous Fine. That was the clarity I was seeking.
Your interpretation is still erroneous though, because you still think the Rindler horizon is a spatial horizon. It is not: it is a velocity limit that in turn limits how quickly and how much a body can accelerate (a rapidity limit). The length of the ship may for all intents and purposes be infinite in the origin's rest frame. As you move to more rapid parts of the ship through one part's frame of reference, you approach but never reach the rapidity of photon emission. And each successive part of the ship is length contracted with respect to the previous, so your ship beyond the origin fits in the space between X=0 and X=1 in that frame. The extent to which this is nuts is the extent to which an infinitely long ship undergoing acceleration is nuts.
This isn't different from what you started out with which my first response treated. Everything west of the Rindler horizon lies outside of the light cone of the part of the ship at the origin in its rest frame. You cannot map out an entire Minkowski space from the light cone of one event. That's fine because that's not what a Minkowski space is: it is a frame of reference containing all events, not just one.
Only in a frame different than the ship frame. That frame is thus arbitrary, and irrelevant to our observer's measure of the distance to the event horizon.
Yes, I acknowledge that in a different frame, that distance is contracted. This seems to be your point,.
It is a singularity, so this does not follow. Suppose the ship extends all the way back to the horizon. Where is the rear of the ship at t=1 (as measured by our observer at x=1)? Follow the t=1 line-of-simultaneity back to x=0 in the diagram. Where does it go? It goes to the same event where it was at t=0, the left-most event in the picture. That shows which event is approached as you move backwards in the accelerating frame. The actual event there is a singularity, with undefined time, so asking which horizon event is simultaneous with our observer at t=1.25 is meaningless, but I can point to the event in your arbitrary Minkowski frame that is approached.
Unclear what you mean by this. Acceleration is continuous, not something that is 'simultaneous'. At all times in ship frame, all parts of the ship are moving at the exact same speed, and thus the entire ship is always stationary in its own accelerating frame. The ship is said to be Born-rigid.
This implies that in a different frame (such as the Minkowski one in the pic), the various parts of the ship are not moving at the same speed. If they did, length contraction would contradict it, as shown by Bell's 'paradox'.
I don't 'think' that. It is a coordinate singularity, just like the one 16 billion light years away, and just like the event horizon of a black hole. The center of a black hole on the other hand is an example of a physical singularity. A coordinate singularity only exists in certain coordinate systems, and there's nothing actually physically weird going on at them. Hence people can drop into a sufficiently large black hole without really noticing any obvious immediate change, not even if they're looking out of the window. A small one of course will kill you before you get there.
Only to the right in this case, not the left. Can't go past x=0. For the same reason, I cannot have a rigid rod much longer than about 27BLY with us stationary at the midpoint. It is an interesting exercise to figure out how to position a rod of twice that length without strain. It can be done. I digress.
I assume 'more rapid' means higher acceleration (and associated rate of change in rapidity) and not high-speed since the ship is always stationary along its entire length in its own frame (the frame in which rapidity is meaningful), so there is no different frame of reference between one part and another. There is a variable rapidity change rate that is dependent on the different parts of the ship. Over at x=1, acceleration is 1, so the rapidity there is a function of how long it's been doing that between two times as measured by a clock there. At higher acceleration parts of the ship, the same time interval results in a greater rapidity change over the same interval on again a local clock. The rapidity of light is infinite, but I don't know what 'rapidity of photon emission' means.
It contains all events in the Minkowski frame, but in real spacetime, light should be able to get here from far away given enough time, but it doesn't in reality, so the Minkowski model fails to describe the large-scale structure of our universe. It is, and always has been, a model of local spacetime.
I have found this page: https://www.gregegan.net/SCIENCE/Rindler/RindlerHorizon.html and wondered if this or something like this is where you've gotten your impression (it talks about spaceships and Rindler horizons). Note the following:
If the above is indeed your source, I hope this convinces you that it is the entire x=0 (or t=infinity) line that is the Rindler horizon, not the X=x=0 point. Next:
This is not a real event horizon like the boundary of the universe or that of a black hole. It is an artificial horizon based on the decision of the ship to constantly accelerate away from everything else. Things effectively cannot reach it (cannot reach x=0) because it moves away from them. However, things can get closer to it (move toward x=0) in its own proper frame. It still has a negative x-direction, and there is no singularity.
Because lightspeed is not observer-independent in non-intertial frames (trivial example: a rotating observer), while it cannot have zero speed, it can have a speed between 0 and c for an observer moving away from it. You seem to think this makes a profound statement about the space behind the accelerating observer, but it doesn't. It is equivalent, in inertial motion, to saying that an object that is following me with the same speed as me doesn't reach me. Or, in my rest frame, a static object to my left is not occupying the same coordinate as me.
The photon is still in the moving observer's coordinate system, it is just always in the negative x positive t quadrant. It isn't the case that space outside the moving observer's light cone is not inside their coordinate system. In other words, you can still create the Minkowski frame from a foliation of the accelerating observer's proper frame, it's just that you have a time-dependent length-contraction to deal with instead of a constant one. A black hole, on the other hand, is a worldline in the Minkowski frame that is genuinely inaccessible to the freefalling observer, i.e. it only exists as an event in the freefalling body's proper frame at eternity.
Similarly, you can accelerate away from Earth to push the distant event horizon further away in the coordinate space of the thing accelerating away, but that just pushes it off. You can't turn off the acceleration of expansion like you can turn off the ship engine. Yes, I agree, the Rindler horizon exists for a continuously accelerating thing, and it ceases to exist when that condition goes away.
Nothing is inherently damaged by free-falling through a black hole event horizon. Are you under the impression otherwise? As I said, a small black hole will 'damage' you before you even get to the event horizon, but that's not the event horizon doing it to you. Orbit close enough to a neutron star and you're dead, no event horizon needed at all.
I was unaware of there being a boundary of the universe. In the ship case, yes, you have the option of turning off the acceleration. In the dark energy case, you do not, so no matter what you choose to do, there are points in space in no significant gravity well from which light can never reach you. This is not true in Minkowski spacetime.
No. My bold. This is where you're wrong. Nothing can ever get closer to it in its own proper frame. That's what I've been repeating in the last several posts.
Maybe you could address my points instead of just repeating your own. The wiki picture shows the proper frames of the accelerating object, and since the picture is a different frame, it actually shows the distance increasing, but in the Rindler coordinates, the distance is constant over time. If it wasn't, there would be a test for absolute rest: when the distance to the rear of the ship is at a maximum. That would be a direct violation of Galilean relativity, the first of the SR postulates.
No argument.
Do you accept that the accelerating object is always stationary in its own frame? I know it's not an inertial frame, but if you take any event on the ship (say the pilot at x=1 at time t=2, his clock), and you reference the one inertial frame in which the pilot is momentarily stationary at that event, then every location along the ship is simultaneously (relative to that IRF) stationary. In that frame, the Rindler horizon is still a distance of 1 behind the pilot, regardless of the time that has passed.
I typically imagine a ship of length almost 2 with the pilot in the middle and the rear just shy of the Rindler horizon, and the front at x=2.
Not the one at the rear. Time is stopped there in that coordinate system, and the photon makes no better progress than one at a black hole horizon trying to get out. A photon anywhere forward of that does indeed make progress and will eventually reach any part of the ship.
Yes, I know. And this is why your argument is incorrect. You seem to think that somehow, in the accelerating observer's frame, the distance from x=0 to x>0 is infinite in the proper frame because nothing from x<0 can reach x=0, akin to saying that if two cars were travelling in the same direction at the same speed, the car behind can't be represented in the rest frame of the car in front because it cannot reach it.
This is quite incorrect except, as I've mentioned several times, when the accelerating body reaches a velocity of c, which it cannot. For all finite accelerations within finite times, there is no infinite time dilation, no infinite length contraction, and any light approaching from the negative x-direction is getting closer, even if it cannot intersect the accelerating body's worldline in finite time. None of this is new: you can do all of the math in standard SR.
Quoting noAxioms
If you'd read me carefully, I not only accept it, I asserted it. This is all x=0 is in the rest frame of the moving body: a coordinate of the origin of that frame. It is not a singularity by any definition.
Quoting noAxioms
The problem is you don't understand the framework you're trying to use to make your point, so don't understand why your point is invalid. I can't address your points in the way you'd like because your conception of Rindler coordinates is wrong, not just incidentally but fundamentally. I am trying to explain what any book on non-inertial motion will explain and frankly I would rather you'd just read one because I do appreciate that you're not going to take correction from a randomer on the internet claiming to be a former relativity lecturer. You have to do the legwork, not just try and jump to the crazy conclusions of some impossible edge cases and mistake that for the theory as a whole.
I never said one car cannot be represented in the frame of the other. That's partly because they're the same car, the front and rear bumper, moving by definition at the same speed in the rigid car's own frame. But the rear bumper must accelerate harder than the front one. The car on the other side of the RH is what cannot be represented in the Rindler frame of the accelerating car. It cannot be keeping up with the accelerating (but stationary) car in the ARF. (Please tell me if any of these acronyms are confusing. I tire of typing the full words).
Yes, and the math says the acceleration cannot be finite at the RH, and which is why I said the length of my object extended almost 1 to the rear, but not all the way, because I wanted to avoid the infinite acceleration required there, with yes, infinite time dilation, just like at the EH of a black hole.
Good. I wasn't sure given your posts.
In the Minkowski frame, we know where the x=0 point is at t=0. It is at X=0, T=0, right? Think wiki picture if you don't know what I mean. Our object extends from X=2 back to X=0. It is effectively a long meter-stick in a rail gun, with a clock at each end and in the middle.
t is what's on the middle clock at the accelerating object at x=1. So at t=2, that clock is off the right side of the picture, but not far. Suppose we stop accelerating the entire object simultaneously (in the object frame) when that clock reads t=2. Where is x=0 in the object's frame? I contend that despite infinite acceleration there, it has gone nowhere and is still at X=0, T=0 (in the original Minkowski coordinates, which is not the object's frame) and not anywhere else on that picture. The clock at the rear of the object still reads zero. Do you agree with any of this? If not, where (in the original Minkowski diagram) is the left end of the object (simultaneous with, in the object's new frame, the cessation of acceleration at t=2 on the middle clock?
You continue to make erroneous assumptions about what I'm saying, so of course you think I'm getting something wrong. No, I never claim a pair of cars following each other are not in each other's reference frames. You totally don't get my point if that's your take.
I'm asking you to do some legwork in the example above, to compute which event corresponds to the cessation of acceleration at the rear of the object, and where that event falls in the original Minkowski diagram. I can do the same mathematics if you like, but the picture already shows the event in question.
You seem to have been claiming that the RH somehow approaches the x=1 point in the ARF as the object accelerates, but in the object's ARF, the object is always stationary, so that can't be happening. It must remain a constant distance from x=1.
The Rindler horizon's similarity to the event horizon is only insofar as any light travelling from the negative x direction cannot reach the x=0 worldline. That seems to be the entire basis for your argument that the space the photon travels in does not exist in the Rindler frame. This is exactly the same as saying the car behind does not exist in the frame of the car in front because it can never reach it. It's the same argument.
Quoting noAxioms
Except for the x=0 (light-like) worldline, yes. But...
Quoting noAxioms
But you don't have to do this. If the acceleration of the leftmost part of the ship is finite at T=t=0, it will not follow the x=0 worldline (the light-line) but one of the x>0 ones. Infinite acceleration is the only way to follow the x=0 worldline. The leftmost end and rightmost end will not have the same horizon in the Minkowski frame, i.e. the horizon is proper-frame--dependent.
[quote=https://en.wikipedia.org/wiki/Bell%27s_spaceship_paradox]Two observers having the same proper acceleration (Bell's spaceships). They are not at rest in the same Rindler frame, and therefore have different Rindler horizons[/quote]
(I am thinking of changing my username to BornRigid but I might get banned.)
As per Bell's paradox, there exists an inertial frame of reference in which we can arrange for the acceleration of the ship to be the same at both ends. As per Wiki:
[quote=https://en.wikipedia.org/wiki/Bell%27s_spaceship_paradox]Consider two identically constructed rockets at rest in an inertial frame S. Let them face the same direction and be situated one behind the other. If we suppose that at a prearranged time both rockets are simultaneously (with respect to S) fired up, then their velocities with respect to S are always equal throughout the remainder of the experiment (even though they are functions of time). This means, by definition, that with respect to S the distance between the two rockets does not change even when they speed up to relativistic velocities.[/quote]
This ship would break apart because each section of it would be length contracted while maintaining its distance from the adjacent section, but the take-home of this is that it doesn't matter where the two ends are. One can always construct another inertial frame at rest wrt the first in which either end is zero or both non-zero. There is nothing special about the initial coordinate of each end of the ship because each end has its own Rindler horizon in its proper frame.
When we choose one of the proper frames, the worldlines of each end will be constrained by the Rindler horizon of the proper frame we choose (either to stay to the right or to the left of it depending on whether the initial position of the other end is to the left or the right of the light-line. Let's take the rightmost end as the proper frame. In its frame, it is not moving, and the left end is moving away from it. To see this, refer again to:
choose the point on the worldline to the right where t=1, and follow the t=1 line back to the other end of the ship. If the leftmost ship is still at x=0 (because it started at X=0), it is still at T=0 in the Minkowski frame, and its velocity is therefore zero: no length contraction occurs at the leftmost end because it is not yet moving. (Length contraction is a function of velocity, not acceleration.)
This ship would break apart in the proper frame of the rightmost end because parts to the left are moving away from the rightmost part with increasing acceleration. The leftmost part's coordinate still exists in the rightmost part's proper frame (indeed, we just traced to that coordinate with our finger).
As I said before, if the length of the ship in the proper frame of the rightmost part is infinite and the leftmost part is at X=x=0 at T=t=0 and the rightmost part has a finite X at some time T, then yes, in the Minkowski frame there will be infinite length contraction fitting the infinite length of the ship into the finite length between the x=0 worldline and X, because in the proper frame of the rightmost part of the ship (at infinity), the leftmost part of the ship is receding away at infinite acceleration. But since this is a physical impossibility, don't worry about it. For all finite lengths, the length contraction is zero or finite everywhere except at t=infinity.
Quoting Kenosha Kid
What light can or cannot do is irrelevant to my point. It is similar in other ways, which is why I brought it up. My arguments have not been based on light signals.
Either car can say what the other is doing 'now', whether they can reach each other or not, so it is not the same at all. You continue to either not get my point, or you're deliberately evading it because its implications make you uncomfortable. So address the question I asked and not another:
A clock is dropped at Rindler event T=0 X=1. What are the Rindler coordinates of that clock when it reads T=1? When it reads T=2?
That's the question. There's no mention of light in it. I claim a lack of coherent answer, and conclude that Rindler coordinates are inadequate to the task of foliating all of spacetime. Similarly, inertial coordinates cannot foliate spacetime containing a black hole, and no coordinate system can foliate spacetime containing multiple black holes.
You cannot talk of length-contraction and hold that what light can or cannot do is irrelevant. That makes absolutely no sense. Relativity is fundamentally tied to the behaviour of light in different frames. Remove that, and you lose the Lorentz transformations. Remove the Lorentz transformations and you lose length contraction. Lose that, and you have no Rindler coordinate system. As tempting as it is for the lay person to jump in at the most fascinating stuff, you have to know the relevant foundations, otherwise you find yourself saying things like the above. Sorry, that's just the way it is.
I have become aware of the fairly recent Schmelzer model, a generalization of Lorentz Ether Theory, that posits a preferred frame for all events, something I said could not be done for 'all events',
It recognizes the inconsistencies I've pointed out, and solves the unordered event problem by denying the existence of the events in question. There are no black holes, only 'frozen stars' with no interior (not even empty space). Infalling observers subjectively die at the event horizon. The big bang also contradicts presentism, and the theory gets around it by positing a big bounce. There is no beginning and no something-from-nothing problem inherent in presentism.
This of course leads to a similar empirical test as there is for an afterlife. You can validate the model, but you can't report the results back to home. Jump into a black hole. If you cross the event horizon without anything noticeably changing, then Einstein's block universe is right and the preferred foliation model is bunk. If you die there, Einstein was wrong. Either way, no paper gets published in a journal.