Does the universe spin?

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Offline Mr. Data

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Does the universe spin?
« on: 08/07/2011 19:28:47 »
According to recent research, scientists are proposing that the early universe may have spun about an axis, meaning the structure of the universe could be a lot more complicated than first imagined.

http://www.stardrive.org/index.php?option=com_content&view=article&id=4596:the-universe-may-have-been-born-spinning-according-to-new-findings-on-the-symmetry-of-the-cosmos&catid=43:science&Itemid=82

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Offline syhprum

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« Reply #1 on: 08/07/2011 19:33:11 »
A meaninless question, by definition the universe is all that there is to spin it must be spinning relative to something else..........
syhprum

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Offline Mr. Data

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« Reply #2 on: 08/07/2011 19:37:13 »
A meaninless question, by definition the universe is all that there is to spin it must be spinning relative to something else..........

This is true. Perhaps we shall see more comparative theories which help to tackle this relativistic problem soon enough. If the universe rotates, then it must be speculated that relativity has it's insights wrong concerning boundary problems.

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Offline Mr. Data

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« Reply #3 on: 08/07/2011 19:40:57 »
We have many models which already attempt at answering these questions, such as Ekpyrotic Theory (which made good use of the dark flows) where the gravitational force finally pushes our universe into another catastrophic depletion of active energy through hitting other universes... or string theory essentially attempts to answer for our universe as branch of many other universes floating in a multidimensional pool. Of course, here at NS we have seen a recent thread (almost along the same tune) http://www.thenakedscientists.com/forum/index.php?topic=40043.0

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Offline Kryptid

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« Reply #4 on: 08/07/2011 22:27:19 »
If the Universe were to spin at a different rate near the "equator" than it did near the "poles" (as is the case with the Sun) it might be detectable by watching the relative velocities of galaxies in these locations.
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Offline Airthumbs

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« Reply #5 on: 08/07/2011 22:57:25 »
What shape would the Universe be in order that it would not be possible to detect the difference in rotation?

I heard it was doughnut shaped........

[attachment=14845]
image from:pinoyexchange.com

If the Universe was "born" spinning as the link states then maybe that's why everything else seems to spin. I have to say the use of the word "born" is very biological and is normally used in reference to childbirth.  Hurry up Planck Satellite, (1rpm)!!  So many questions!!!
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Offline yor_on

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« Reply #6 on: 08/07/2011 23:06:01 »
This handedness seems random as I understand it? There is no angular momentum mentioned for the Big Bang, as I know? If you imagine there was, and then add the newly created mass in it as it expands, making our 'sphere' bigger, we should see and feel it, I think? But I'm not sure there.

That is if we assume the universe spinning relative 'something'. Because without anything to 'spin' against, if we treat the universe as 'one whole thing'? I don't know, can we define a 'spin' that way? Newton thought we could, but Einsteins spin is defined by all mass, called frame-dragging, isn't it? So either all things we see 'spinning' take themselves out, giving no universal net angular motion observable, no matter if we were found to be spinning relative some 'outside', or they do not?

Gravity probe B has, as far as I know, proven the geodetic effect, how a invariant mass can 'warp/wrap' space around itself, and also time, as defined by some other frame of reference. And then frame-dragging, how a spinning object can drag space and time along in its rotation, so we know that 'space' adapts to mass and motion. And, if 'dragging' that to its logical conclusion, that should also mean that that the opposite must be true, otherwise we will have to find another way to describe a symmetry.

If they don't, How is that possible? Headache time :)
« Last Edit: 08/07/2011 23:08:11 by yor_on »
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Offline Airthumbs

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« Reply #7 on: 08/07/2011 23:21:36 »
Maybe it's because it is space-time that drags and as time has an "arrow" symmetry does not apply, unless we can move time backwards?
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Offline yor_on

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« Reply #8 on: 08/07/2011 23:29:59 »
Think of it this way, use the balloons surface to define that there are no center to the universe (2D). Then define it as gravity probe B, mass warp/wrap the space around itself and if that mass also rotate it also will drag the space with it. How does it do that? It does it relative all other mass, or 'gravity' if you like to do as I :)

So you have a 3D (4D depending) space that interact with itself. How would you now prove it all to be spinning without a 'outside referent'? Let's say we isolate a piece of 'space' and as it is defined as 'isotropic' and 'symmetric', as in being pretty much the same everywhere, obeying the same laws, I think we are free to do so. Then try to count all 'frame dragging' you see and look at if it evens out or not, if it doesn't, have we now found a 'universal angular motion'? We can't really define it like this I think, there are no reasons why everything has to be 'perfectly isotropic' from a entropic point of view, not as long as the whole of 'SpaceTime' is. And there is no way we ever will see the whole of SpaceTime, as I know. Also in Einsteins universe we have no absolute frames of reference, we have definitions we call inertial, to me speaking about uniform motion in where the only real definition is that they are at rest with 'gravity's potential' as I see it. So if you want to define a universal spin, you might have to define a absolute frame of reference first from 'where we can move the earth', or the universe, as this is about.

So, anyone, do you have a better idea how we could do it?
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Offline yor_on

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« Reply #9 on: 08/07/2011 23:35:58 »
Ah this was not a answer to your idea Airthumbs, we just 'collided' in Cyberspace :) Time symmetry apply in QM, but macroscopically we do have a arrow.
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Offline Mr. Data

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« Reply #10 on: 08/07/2011 23:38:37 »
Think of it this way, use the balloons surface to define that there are no center to the universe (2D). Then define it as gravity probe B, mass warp/wrap the space around itself and if that mass also rotate it also will drag the space with it. How does it do that? It does it relative all other mass, or 'gravity' if you like to do as I :)

So you have a 3D (4D depending) space that interact with itself. How would you now prove it all to be spinning without a 'outside referent'? Let's say we isolate a piece of 'space' and as it is defined as 'isotropic' and 'symmetric', as in being pretty much the same everywhere, obeying the same laws, I think we are free to do so. Then try to count all 'frame dragging' you see and look at if it evens out or not, if it doesn't, have we now found a 'universal angular motion'? We can't really define it like this I think, there are no reasons why everything has to be 'perfectly isotropic' from a entropic point of view, not as long as the whole of 'SpaceTime' is. And there is no way we ever will see the whole of SpaceTime, as I know. Also in Einsteins universe we have no absolute frames of reference, we have definitions we call inertial, to me speaking about uniform motion in where the only real definition is that they are at rest with 'gravity's potential' as I see it. So if you want to define a universal spin, you might have to define a absolute frame of reference first from 'where we can move the earth', or the universe, as this is about.

So, anyone, do you have a better idea how we could do it?

As Doctor Michio kaku reminds us scientists, is that all the equations of the universe can be modelled to suit the idea that our universe is nothing but a black hole. This theory has been going around for a while now - if this was true (and here I use this as a thought-experiment), then our universe would be an electromagnetically-charged black hole, which in this case, would be spinning. If it were a black hole, then almost certainly we can be allowed within it's structure and exist, and see a universe much like our own in many respects, and not be worried about relativistic laws where rotation must be relative to something else, because if we really are in a black hole, then the physics states that there must be something outside our own universe.

Expand your minds people :P

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Offline yor_on

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« Reply #11 on: 08/07/2011 23:45:32 »
And I agree AT, the symmetry should be about 'times arrow'. Like some 'still pictures' in where we see flows and streams (vectors sort of), and as we quickly start to flip through the pages in one direction, we find a universe, changing in its arrow.

And yes MD, if we have a frame of reference relative the universe, then we might be able to assume a rotation, but how would we prove it?
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Offline yor_on

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« Reply #12 on: 08/07/2011 23:51:13 »
The only way I can think of is if that 'outside' could 'communicate' with us in a, for us, perceivable fashion. A black hole is defined by its Event Horizon as I see it, and even though you have entanglements possible, according to Hawking radiation, how would you know? The Black Holes are expected to last longer than our universe, meaning they will be the last to start radiate. Let's put it this way, we know that a Black Hole will influence the space outside it, does the universe influence the space inside the Event Horizon? If it does, and we have a BH inside a BH, inside a BH a.s.o :) there should be a effect from it, don't you agree? Some gravitational anomalies at least?

Are there?
« Last Edit: 08/07/2011 23:55:10 by yor_on »
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Offline Mr. Data

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« Reply #13 on: 08/07/2011 23:54:39 »
And I agree AT, the symmetry should be about 'times arrow'. Like some 'still pictures' in where we see flows and streams (vectors sort of), and as we quickly start to flip through the pages in one direction, we find a universe, changing in its arrow.

And yes MD, if we have a frame of reference relative the universe, then we might be able to assume a rotation, but how would we prove it?

Well, we may already have a mathematical proof. It can be explained very easily - I do recall reading from a paper: We all know that the radius of a black hole is proportional to its mass. This is simply (R≈M) so from there, you know the density of a black hole is provided by the mass divided by the volume, which is of course: (D=M/V) - this is pure quantum mechanics and geometry being introduced here. The volume is proportional to the radius of a black hole rasied to the power of three so (V≈R³) so the density of something exotic like a black hole is in fact proportional to it's mass raised to the second power (D≈M²).

This means that if someone was sitting inside a black hole, it would not appear as dense as someone who was relatively sitting outside of the black holes horizon. So as we see, there might be a mathematical proof. How we come to prove it with experimentation is another deal entirely.

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Offline yor_on

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« Reply #14 on: 08/07/2011 23:59:23 »
Yes, but we should be able to see gravitational influences if there was a two way communication, but as far as I know the Event Horizon is where our universe 'breaks of' leaving us with something that do not communicate more than one way, from us to it. All 'time' points to its center so to speak.
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Offline Airthumbs

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« Reply #15 on: 09/07/2011 00:05:02 »
I don't see why you would need a frame of reference to detect movement unless that frame of reference is time? All you would need is information over time and then a comparison.  I suppose that frame of reference is whatever information you use so maybe I just answered my own question?  [;D]  Hows that for confused!

If the universe was rotating we would see movement in different directions from the information.  Even the expansion of the universe could actually be movement defined as evidence of a spinning universe.  If space-time is expanding faster then the speed of light that universal spin is what creates gravity through a kind of gyroscopic effect!
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Offline yor_on

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« Reply #16 on: 09/07/2011 00:06:41 »
So how about this, let us for fun assume a Black hole in where there comes a he* of a lot of mass, from our point of view outside it would 'hang there' outside the EV. From the point of view of the mass it would move, as I see it, finding no trouble pass what we call the EV into the center. From the point of view of someone being inside that 'space' inside the EV, being still relative its 'center' as we can assume for this. Would he notice gravity change.
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Offline Mr. Data

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« Reply #17 on: 09/07/2011 00:09:10 »
At this moment in time, I do not know how. You might be able to leave a black hole in theory. Maybe through quantum tunnelling - afterall, this is how Hawking Radiation works.

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Offline Airthumbs

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« Reply #18 on: 09/07/2011 00:10:27 »
Would you be escaping the blackhole into what exactly?  Our Universe?
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Offline yor_on

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« Reply #19 on: 09/07/2011 00:13:11 »
AT all rotations must be relative something. The universe as a whole also will need a definition relative it rotates. You might want to use gravity for it, it makes the most sense to me at least. But that's all inside this universe, so to get it to 'work' you also need something 'communicating' as I see it, from that 'outside'?
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Offline Mr. Data

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« Reply #20 on: 09/07/2011 00:15:13 »
Would you be escaping the blackhole into what exactly?  Our Universe?

Into the universe which contains the black hole. As far as we are concerned (in theory of of course) the black holes inner horizons would be our universe. The black hole has more than one horizon within it's structure. One part of the horizon is where space and time move like they do in our universe, which is different to an observer who just falls into a black hole, because time becomes spacelike and space timelike. They switch roles, that is, until you fall into another horizon located inside the black hole.

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Offline Airthumbs

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« Reply #21 on: 09/07/2011 00:25:39 »
Sounds like a tunnel?
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Offline Mr. Data

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« Reply #22 on: 09/07/2011 00:27:11 »
My knowledge is limited on black holes, but I do believe it is like a tunnel - you cannot move freely in the space of a black hole until you pass the inner horizon - these inner structures only exist if the black hole rotates.

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Offline Mr. Data

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« Reply #23 on: 09/07/2011 00:30:22 »
http://schools-wikipedia.org/wp/b/Black_hole.htm

''Possibility of escaping from a rotating black hole

Penrose diagrams of various Schwarzschild solutions. Time is the vertical dimension, space is horizontal, and light travels at 45° angles. Paths less than 45° to the horizontal are forbidden by special relativity, but rotating black holes allow for travel to future "universes"Kerr's solution for the equations of general relativity predicts that:

The properties of space-time between the two event horizons allow objects to move only towards the singularity.
But the properties of space-time within the inner event horizon allow objects to move away from the singularity, pass through another set of inner and outer event horizons, and emerge out of the black hole into another universe or another part of this universe without traveling faster than the speed of light.
Passing through the ring shaped singularity may allow entry to a negative gravity universe.
If this is true, rotating black holes could theoretically provide the wormholes which often appear in science fiction. Unfortunately, it is unlikely that the internal properties of a rotating black hole are exactly as described by Kerr's solution and it is not currently known whether the actual properties of a rotating black hole would provide a similar escape route for an object via the inner event horizon.

Even if this escape route is possible, it is unlikely to be useful because a spacecraft which followed that path would probably be distorted beyond recognition by spaghettification.''

There is also some talk in the article conerning the inner event horizons.

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Offline Airthumbs

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« Reply #24 on: 11/08/2011 02:19:33 »
If our Universe, and I say if, was created by a black hole then I suspect that it would be spinning or at least would have milliseconds after the big bang. After the bang, due to the rapid expansion of the Universe, that spin then might have ceased to apply to the whole Universe. The energy from this original spinning singularity could be the reason why everything else spins in our Universe including Blackholes, Neutron Stars, Atoms and my head when I think about this!

Something a bit odd about the Universe, it seems that things exists inside it that we think about, then we look, then guess what, we discover it!  Having said it's a bit odd, so is quantum mechanics, one thing that stands out in the perspective of the Universe is; what does it get upto when no one is looking?  And by observing our Universe are we changing it in some way? 

If someone sais, maybe our Universe is spinning, all of a sudden we have a Universe that could be spinning and not spinning at the same time, and that would mean we have to have at least two!

Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction. (Einstein)

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Offline graham.d

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« Reply #25 on: 11/08/2011 08:29:11 »
A meaninless question, by definition the universe is all that there is to spin it must be spinning relative to something else..........

Actually it is not a meaningless question. Rotation of a system has measurable effects from inside the system. The issue of how to define the universe may come into play of course; it may defined as a system beyond which we can never venture or, for example, a many-fold set as part of a multi-verse.

Anyway there has been some recent experimental evidence to suggest that the universe has a net angular momentum. The work involved measuring the angular momentum of a large number of surrounding galaxies. The result showed that the net momentum was non-zero to a statistically significant degree. The limitations to the experiment is that we can only see, and measure/estimate, so far and it may be that the net angular momentum in our region of space is compensated elsewhere but beyond our view. See Prof Michael Longo (University of Michigan). They looked at space up to 600 million lightyears distance. It would have a very significant impact on cosmological models.

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Offline yor_on

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« Reply #26 on: 12/08/2011 21:12:23 »
Oh yes it would Graham, it would allow 'time travel' :)

And that's a totally other barrel of fish.
So I will continue to presume that it's not rotating :)
heh.
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Offline graham.d

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« Reply #27 on: 13/08/2011 07:19:09 »
Yor_on, you lost me with the relation between a non-zero angular momentum for the universe and the concept of time travel (which I assume you mean backward time travel with all the resulting paradoxes). What/whose theory is this?

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Offline yor_on

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« Reply #28 on: 13/08/2011 17:49:35 »
"In 1949, the mathematician Kurt Godel - a friend of Einstein's and a colleague at Princeton University's Institute for Advanced Study - decided to tackle a situation where the whole universe is rotating. In Godel's solutions, time travel was actually allowed by the equations ... if the universe were rotating. A rotating universe could itself function as a time machine.

Now, if the universe were rotating, there would be ways to detect it (light beams would bend, for example, if the whole universe were rotating), and so far the evidence is overwhelmingly strong that there is no sort of universal rotation. So again, time travel is ruled out by this particular set of results. But the fact is that things in the universe do rotate, and that again opens up the possibility."

"In 1949, when his good friend Kurt Gödel showed that a rotating universe allowed for time travel, he was deeply worried.

Gödel, in fact, would pester astronomers visiting Princeton and ask if there was any sign that the universe was rotating. In Einstein’s writings, he finally concluded that time travel might be inherent in his equations, but they can be dismissed "on physical grounds," i.e., they could not form using known physical mechanisms. In other words, the universe expanded, not rotated. So if the universe did rotate, then time travel might be an everyday occurrence. This argument holds even today. There are a large class of solutions of Einstein’s equations, but many can be dismissed "on physical grounds." For example, in 1937, W.J. Van Stockum showed that a spinning cylinder that was infinitely long could satisfy all of Einstein’s equations. Decades later, it was shown that the Stockum solution actually allowed for time travel. If you danced around this cosmic Maypole fast enough, you could come back before you left. But again, "on physical grounds," one can argue that cylinders can never be infinitely long, so this was just a mathematical curiosity."

Then you have Black Holes, 'stabilized' worm holes clad with 'exotic (negative) matter/energy' etc. So the math seems to allow it, but I don't think it will work in reality.

Time travel Physics.

==
I think of it like this. Assume that there is a universal 'same clock'. Let's use light as that clock. You are born and now it start ticking for you, I'm born and it starts ticking for me. But those clocks, although having the same exact durations, as we will find whn being in the same 'frame of reference' is also uniquely our own as shown by a 'time dilation'. Two synchronized clocks on a table, move one to the floor, see their durations start to differ with gravity's influence.

If you travel near light the universe might pass forward at furious pace time wise as far as you are concerned, but your rate of durations do not change, you do not become in 'slow motion' and the arrow still only have one way, for all involved. There is a symmetry in that. But there is no symmetry in assuming that your 'arrow of time' both can point forward. at the same time as it points 'backwards' to me as in backwards time travel. How would it do that?

The clocks we have is uniquely our own, although belonging to a same conceptual common 'ground state' as I see it. To assume that the rest of the universe would be the one ticking backwards becomes just as confusing, as if you share their frame surely would find only one arrow, pointing in one direction, same as always.
« Last Edit: 13/08/2011 18:07:21 by yor_on »
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Offline graham.d

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« Reply #29 on: 13/08/2011 18:23:46 »
Shows my ignorance, Yor_on; I didn't even know Godel had worked on this stuff. I only know of his famous incompleteness theorem. Bright bloke, Godel!

It's hard to "see" why a rotating universe allows time travel; but then most solutions in GR are also fairly non-intuitive, to say the least.

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Offline yor_on

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« Reply #30 on: 13/08/2011 19:50:39 »
Heh, I agree Graham, and it gives me no little headache accepting the idea. I suppose it has to do with time being a function of the room, but where to go from there to find time reversing I can't say. To me a time reversal must be a situation where the arrow still have to point into the 'future' to make it work. Maybe it becomes a question of where the 'future' points? I don't know, but I'm pretty sure that the only way 'time travel' can be consciously experienced should be when your own local arrow act 'as usual'. And that one seems always to be true when we look at 'time dilations', so to make it 'work' in reverse that arrow, and all chemical, thermodynamical,  processes should have to behave 'as usual', for me to observe it.

I mean, assume that the universe just 'backed' ah, ten minutes, From where would you have a clue? all processes in this universe should then have 'backed'. The other way is to assume that you can do so locally, relative a universe. But how would it work? Talking about 'energy expended' for example. Ten minutes of a whole universe 'expending energy' nullified? It boggles my mind that one.

==

In fact, the only way I can make sense of it is from assuming a 'static' point of view, from where we have no arrow at all. If it was that way we could assume that it takes no 'energy' at all, possibly, to reverse 'time'. That as time then can't exist. But then all our ideas about energy must be wrong, and probably most of the rest too. Because they are all a function of time as I see it.
« Last Edit: 13/08/2011 19:59:36 by yor_on »
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Offline CPT ArkAngel

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« Reply #31 on: 13/08/2011 19:53:58 »
If i remember well, in Godel's model, all the universe including space must be rotating to allow time reversal, which has already been disproved. In the actual observations, it is matter rotating in space...

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Offline yor_on

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Does the universe spin?
« Reply #32 on: 13/08/2011 20:05:40 »
Well, then the question becomes, assume that space is 'rotating'. From the aspect of light 'propagating' space shows no resistance. From the aspect of what modulates that space into its ever changing shape, gravity, I don't think space as such will influence that. From the view point of vacuum fluctuations? I don't know. A rotating space presumes a 'motion', and is to me a mostly 'classical' definition, valid inside Planck time as I see it. From a QM perspective both time and motion seems suspect :)

It's a very weird thought, also it would once and for all stamp 'space' as a classical medium in its own right if it was correct.
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Offline yor_on

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Does the universe spin?
« Reply #33 on: 13/08/2011 20:21:31 »
Then again, I think of the 'space' as a function of just gravity, assuming that they are hand in glove. Without 'gravity' no measurable space, possibly. We have those other forces too of course, but somehow both space, gravity, time and matter seems to be one thing as if they come out of something united, then broken into the fragments that defines 'SpaceTime' to us. Maybe you can 'back' it, but it seems very weird to me to assume that you can back time. Assuming that you believe in lights 'propagation' you now have a scenario in where you if defined as a 'frame of reference' have your arrow still pointing into the future locally, observing all other processes reverse. It's the Wheeler-Feynman Absorber Theory all over, thinking of light there.
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But, from a 'static perspective' it's possible though. But then you need to stop considering light as 'propagating'. In fact, in a static universe the only thing creating what we see would be the process we call 'times arrow'. It is needed for all interactions, without a arrow you can not have a interaction. And to use a chemical or thermodynamical process to define 'time' is a self-contradiction in that all such processes presumes a 'linear' causality chain, to show us this unique constant repeatability. And that 'chain' is what I call the 'arrow of time'. I think of time as a function of the room, and if that is true you can see it two ways. Either as 'time' is the room, or as if 'time' gets defined by the room. But it is weird, and I don't really know :)
« Last Edit: 13/08/2011 20:49:58 by yor_on »
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Offline CPT ArkAngel

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Does the universe spin?
« Reply #34 on: 13/08/2011 20:48:59 »
There is no official unification theory yet and Einstein himself said that Relativity is incomplete. And you are right about propagating, it would be expansion of energy rather than propagation, by definition...  [;)]

Without a unification, it is speculation...