Universal 'Now' at Time-Zero

[StringJunky]

String Junky,

 

Probably a question for another thread, but if the distance between A and B does not change because they are within 200million lys of each other and the distance between B and C does not change because they are within 200 million lys of each other, where has the distance between A and C increased, even though they are 400 million lyrs distant and the forces of expansion should be in force?

 

Regards, TAR

A is bound to B and B is bound to C. They are a gravitationally bound group.

[tar]

String Junky,

 

So the whole universe is gravitationally bound? That is, every item is within 200million lyr of 200million lyrs worth of other items?

 

Where would there be space that could expand? If not between A and B or A and D or A and Z or between A and ZZZZZZZZZ?

 

Regards, TAR

Or is it like a soap bubble where the soap adheres to soap and the other side of the void gets further away as the bubble grows?

Edited August 20, 2016 by tar

[StringJunky]

String Junky,

 

So the whole universe is gravitationally bound? That is, every item is within 200million lyr of 200million lyrs worth of other items?

 

Where would there be space that could expand? If not between A and B or A and D or A and Z or between A and ZZZZZZZZZ?

 

Regards, TAR

Or is it like a soap bubble where the soap adheres to soap and the other side of the void gets further away as the bubble grows?

The large scale structure is made up of cobwebby filaments of interconnected galaxies and gasses; it's that space between those filaments that will expand.

 

[tar]

My question really is: does it make sense that if everything is physically connected and homogenous, time doesn't exist because everything happens simultaneously everywhere in that state?

 

StringJunky,

 

So, the strings of galaxies are more "physically connected" than the voids between, which may have developed during expansion, or may have started existing during the inflation stage (do you know when voids started?) but must have, time wise, started to form sometime after the hot/dense phase. I am guessing that a void would be counter intuitive to a hot/dense phase. But still if you travel with light along a fiber of the web, it takes time to get from one part of the string to the next. Even without a void between, there would be distance for impulses to cover.

 

Regards, TAR

Edited August 20, 2016 by tar

[StringJunky]

 

StringJunky,

 

So, the strings of galaxies are more "physically connected" than the voids between, which may have developed during expansion, or may have started existing during the inflation stage (do you know when voids started?) but must have, time wise, started to form sometime after the hot/dense phase. I am guessing that a void would be counter intuitive to a hot/dense phase. But still if you travel with light along a fiber of the web, it takes time to get from one part of the string to the next. Even without a void between, there would be distance for impulses to cover.

 

Regards, TAR

What is distance when there was no space, no space no time. . Space and time are interrelated, remember.

[geordief]

Is there a notion that at some point in the distant past the things we now see as distinct were actually "one thing".?

 

I don't see how the transition from this state to a differentiated state might have been accomplished.

 

If that state ever existed ,surely even an outside intervention could not have caused it to differentiate,

 

So can we only be imagine a state that was extremely homogeneous but not in all respects?

 

If there was a state of 100% homogeneity would that also imply or require pure symmetry also.(or would that even concept not apply)

[StringJunky]

Is there a notion that at some point in the distant past the things we now see as distinct were actually "one thing".?

 

I don't see how the transition from this state to a differentiated state might have been accomplished.

 

If that state ever existed ,surely even an outside intervention could not have caused it to differentiate,

 

So can we only be imagine a state that was extremely homogeneous but not in all respects?

 

If there was a state of 100% homogeneity would that also imply or require pure symmetry also.(or would that even concept not apply)

I think quantum fluctuations are hypothesised to have initiated the inhomogenity and instability which kicked it off.

[tar]

StringJunky,

 

But conceptually do you place the quantum fluctuations over here and over there and happening in sequence, or do you think one quantum fluctuation occurred everywhere at once?

 

That is, was there already time and space within which the fluctuations occurred, or did a singularity bifurcate due to some accident and then continued to evolve in reaction, or some attempt to get back to the static situation that existed prior the accident?

 

Regards, TAR

[StringJunky]

StringJunky,

 

But conceptually do you place the quantum fluctuations over here and over there and happening in sequence, or do you think one quantum fluctuation occurred everywhere at once?

 

That is, was there already time and space within which the fluctuations occurred, or did a singularity bifurcate due to some accident and then continued to evolve in reaction, or some attempt to get back to the static situation that existed prior the accident?

 

Regards, TAR

If there is no space there can't be 'over here and over there'. They are a function of space.

Edited August 20, 2016 by StringJunky

[geordief]

This seems a bit weird. We have hypothetically an homogeneous state that is affected by a fluctuation.

 

Can we ask if this fluctuation is exterior or interior to the state? (is it a question that it is actually permitted to ask or does it bring in or require spacetime which apparently does not exist in that circumstance?)

 

Can it be integral to the state?

 

How could this fluctuation destabilize the state?

 

Is it rather that the fluctuation prevents the homogeneous state from ever establishing itself ?

[StringJunky]

This seems a bit weird. We have hypothetically an homogeneous state that is affected by a fluctuation.

 

Can we ask if this fluctuation is exterior or interior to the state? (is it a question that it is actually permitted to ask or does it bring in or require spacetime which apparently does not exist in that circumstance?)

 

Can it be integral to the state?

 

How could this fluctuation destabilize the state?

 

Is it rather that the fluctuation prevents the homogeneous state from ever establishing itself ?

No idea.

[MigL]

Quantum fluctuations are by definition, not localized in space or time.

You have heard of the HUP, haven't you?

[StringJunky]

Quantum fluctuations are by definition, not localized in space or time.

You have heard of the HUP, haven't you?

That's what I thought.

[geordief]

Quantum fluctuations are by definition, not localized in space or time.

You have heard of the HUP, haven't you?

Never in this quite extraordinary context (not that I would be on top of it in any context but that is just the level I am at)

[Strange]

Never in this quite extraordinary context (not that I would be on top of it in any context but that is just the level I am at)

 

 

That is where the tiny fluctuations in the CMB, and hence the large scale structure of the universe, are thought to come from.

[geordief]

 

 

That is where the tiny fluctuations in the CMB, and hence the large scale structure of the universe, are thought to come from.

Does that make any difference to the way one thinks about quantum theory -that it may be instrumental to the very genesis of the universe we are living in ?

 

Does it give it some kind of hierarchical seniority over GR because it was there before ("before" ?) GR came into play.

 

Might GR be explained via quantum theory but not vice versa?

Edited August 20, 2016 by geordief

[StringJunky]

Does that make any difference to the way one thinks about quantum theory -that it may be instrumental to the very genesis of the universe we are living in ?

 

Does it give it some kind of hierarchical seniority over GR because it was there before ("before" ?) GR came into play.

 

Might GR be explained via quantum theory but not vice versa?

GR only explains the macro world; bigger than an atom.

[tar]

Just read that a particle coming into existence due to a quantum fluctuation lasts a very short time and the more energy the shorter. A universe would have a lot of energy and therefore if the HUP holds in this case the universe would have left existence immediately upon arriving.

[StringJunky]

Just read that a particle coming into existence due to a quantum fluctuation lasts a very short time and the more energy the shorter. A universe would have a lot of energy and therefore if the HUP holds in this case the universe would have left existence immediately upon arriving.

But it's not just one particle; it's a rather large number of them spontaneously and randomly doing so. The distribution will be heterogenous because of that randomness and that's what ultimately, it is hypothesised, to have determined the large-scale structure.

Click image to enlarge

http://cosmicweb.uchicago.edu/filaments.html

Edited August 20, 2016 by StringJunky

[Strange]

Does that make any difference to the way one thinks about quantum theory -that it may be instrumental to the very genesis of the universe we are living in ?

 

Does it give it some kind of hierarchical seniority over GR because it was there before ("before" ?) GR came into play.

 

Might GR be explained via quantum theory but not vice versa?

 

 

I'm not sure. But it makes it very clear that we need a theory of quantum gravity before we can understand the earliest history of the universe.

[MigL]

Any theory of 'Quantum gravity' has to reduce to quantum mechanics at the low-energy, small scale limit and general relativity at the large scale limit.

[michel123456]

The large scale structure is made up of cobwebby filaments of interconnected galaxies and gasses; it's that space between those filaments that will expand.

 

So, in this kind of structure, when the voids expand the filaments must be stretched I suppose?

[StringJunky]

So, in this kind of structure, when the voids expand the filaments must be stretched I suppose?

Yeah, that's what seems to happen in the universe-in-a-box simulations. Mass-density won't be even along the filaments.

Edited August 21, 2016 by StringJunky

[tar]

StringJunky,

 

That picture of the filiments. How "true" is it? Is it a computer model, or is it constructed from actual data? How enhanced is it, and do you know the scale modifications and color modifications and brightness modifications? Which direction is it taken in, and what would it look like in the other direction? The reason I ask is several fold. One from remembering that there is a great attractor that semi local galaxies seem to be influenced by, when cataloging the relative motions of the galaxies, and it would be good to see what that "looks like" in terms of filiments. Two, I have this thing about distant things, that they show us arrangements from the past, and was wondering what kind of corrections were applied to the data, to paint a filament picture where all components were of the same age and what age that might be representing. That is, is it the way it looks when you look, or is it the way the current universe is probably arranged, according to extrapolation and imagination.

 

The difference being, if it is from actual data, one can make inferences from the arrangement. If on the other hand its an artist's rendering, you can explore only the artist's mind.

 

Regards, TAR

Why the question is important to me, for this discussion, and others, is because like(you) StringJunky considering a whole universe as homogeneous and events happening everywhere at once, people tend to consider the whole universe at once, and I tend to think it is way to big for that, and that the distance itself is one of the most important defining factors in the reality of the place. It is exactly what keeps everything from happening at once. And one important reality, that a brain that is within the universe, can take a picture of the place, or build a model, but neither is as true as the place itself.

Edited August 21, 2016 by tar

[StringJunky]

That picture of the filiments. How "true" is it? Is it a computer model, or is it constructed from actual data?

Both.

 

 

How enhanced is it, and do you know the scale modifications and color modifications and brightness modifications?

I doubt it is made to that degree of finesse or that it is even desired.

 

 

Which direction is it taken in, and what would it look like in the other direction?

It doesn't matter, the universe looks the same in all directions; it's isotropic.

 

 

The reason I ask is several fold. One from remembering that there is a great attractor that semi local galaxies seem to be influenced by, when cataloging the relative motions of the galaxies, and it would be good to see what that "looks like" in terms of filiments.

It doesn't represent the whole universe; just a a cube section of volume size that I can't remember right now.

 

 

Two, I have this thing about distant things, that they show us arrangements from the past, and was wondering what kind of corrections were applied to the data, to paint a filament picture where all components were of the same age and what age that might be representing. That is, is it the way it looks when you look, or is it the way the current universe is probably arranged, according to extrapolation and imagination.

The still sequences represent the formation of the filaments over time. The images are snapshots from a computer-generated, animated simulation showing an extrapolation of the universe's evolution using observed data, plugging in the parameters of the Cold Dark Matter Model and letting the program run.

 

 

Why the question is important to me, for this discussion, and others, is because like(you) StringJunky considering a whole universe as homogeneous and events happening everywhere at once, people tend to consider the whole universe at once, and I tend to think it is way to big for that, and that the distance itself is one of the most important defining factors in the reality of the place. It is exactly what keeps everything from happening at once. And one important reality, that a brain that is within the universe, can take a picture of the place, or build a model, but neither is as true as the place itself.

The boxes are sample sections, not the whole universe, and relativistic effects in the simulation will not be modelled; it's not what that simulation-model is trying to show. Models describe pre-defined aspects of the phenomena under investigation; they are not the whole story, just like geographical maps illustrate only certain aspects of the territory.

 

Here's the movie of that simulation:

 

Edited August 21, 2016 by StringJunky