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Paradox and Creation
Posted: 18 September 2016 02:57 AM   [ Ignore ]   [ # 16 ]
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GdB - 17 September 2016 11:54 PM
Write4U - 17 September 2016 03:04 AM

In this scenario, what is the definition of *the Universe*.  Is that observation in regards to the expanding Universe as we know it or does it address an infinite *permittive condition* (vacuum) into which the Universe IS expanding?

Cosmologists all agree that the universe is not expanding into something else. Vacuum is space with nothing in it. So if space itself is expanding, in what is it expanding? Without basic understanding of general relativity, this will stay incomprehensible for you.

Actually I have little problem with visualizing abstract landscapes.

But let’s look at what has been said here. “vacuum is space with nothing in it” . I agree, but as this infinite empty space cannot be counted as infinite spacetime, I named it more correctly as a *permittive condition* which allows for expansion of the universe.

By your own words our universe did have a beginning (13.7 billion years ago), during which “spacetime” (this universe) was born.
By your analysis, infinite space has always existed and the BB was the birth of physical stuff and time. As I understand Einstein, space was never disconnected from time, thus the phrase “spacetime”.  It also would contradict the following representation of the Universe.

The Universe can be defined as everything that exists, everything that has existed, and everything that will exist.[20][21][22] According to our current understanding, the Universe consists of spacetime, forms of energy (including electromagnetic radiation and matter), and the physical laws that relate them. The Universe encompasses all of life, all of history, and some philosophers and scientists suggest that it even encompasses ideas such as mathematics and logic

That’s why I like Tegmark’s work.

Discoveries in the early 20th century have suggested that the Universe had a beginning and that it is expanding[16] at an increasing rate.[17] The majority of mass in the Universe appears to exist in an unknown form called dark matter.

The Big Bang theory, the prevailing cosmological model describing the development of the Universe, states that space and time were created in the Big Bang and were given a fixed amount of energy and matter that becomes less dense as space expands. After the initial expansion, the Universe cooled, allowing the first subatomic particles to form and then simple atoms. Giant clouds later merged through gravity to form stars. Assuming that the standard model of the Big Bang theory is correct, the age of the Universe is measured to be 13.799±0.021 billion years

https://en.wikipedia.org/wiki/Universe

This may be of interest: http://www.space.com/52-the-expanding-universe-from-the-big-bang-to-today.html

Instead of using the term “vacuum” for “empty space”, I prefer to use the term “permittive condition” , which can be of any size from zero to infinity.  I find the following quote:

The vacuum is the most absolute ground state: no waves, no particles, nothing at all to elevate the energy above zero*.

http://www.askamathematician.com/2012/07/q-what-is-the-false-vacuum-and-are-we-living-in-it/

In quantum field theory, a false vacuum is a metastable sector of space that appears to be a perturbative vacuum, but is unstable due to instanton effects

Using the term a *permittive condition* (pertubative vacuum) does not contradict any speculative description of an expanding universe or even a multiverse or infinity.  But our universe (spacetime) has a distinct shape and is expanding. It is not infinite in size.

It is in fact a purely abstract term.

[ Edited: 18 September 2016 03:09 AM by Write4U ]
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Posted: 18 September 2016 06:27 AM   [ Ignore ]   [ # 17 ]
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Write4U - 18 September 2016 02:57 AM

By your own words our universe did have a beginning (13.7 billion years ago), during which “spacetime” (this universe) was born.

That were not my words, but OK, I do not disagree with them.

Write4U - 18 September 2016 02:57 AM

By your analysis, infinite space has always existed and the BB was the birth of physical stuff and time.

No. First I would not call my posting an analysis: it was more of a statement. And nowhere I implied that ‘infinite space has always existed’, on the contrary.

Write4U - 18 September 2016 02:57 AM

It is in fact a purely abstract term.

Yes. Too abstract, to be of any use.

Why don’t you just read modern day cosmology, and be just astonished about the vista’s presented to you? It is great stuff, but the real understanding is far above your head. Also above mine, but at least I understand so much of it that I know it is above my head.

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Posted: 18 September 2016 04:11 PM   [ Ignore ]   [ # 18 ]
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GdB said,
No. First I would not call my posting an analysis: it was more of a statement. And nowhere I implied that ‘infinite space has always existed’, on the contrary.

This is what you said (quote from wiki)

“suggest that the Universe is infinite in extent with a finite age

And this makes the problem easier to solve? It suggests that our universe is already infinite, something which is being debated by the scientific community.

This suggestion leads to , “Our universe began as an infinitely large singularity.

EXTENT, NOUN:

1.the area covered by something: “an enclosure ten acres in extent”

synonyms: area · size · expanse · length · proportions · dimensions

In context, this indicates an a priori *infinite permittive condition*.

EXTEND, VERB:
1.cause to cover a larger area; make longer or wider:

“the Forest Service plans to extend a gravel road nearly a mile”

synonyms: expand · enlarge · increase · make larger · make bigger ·

This indicates an infinitely expanding universe in an a priori *infinite permittive condition*.

Can’t have an expanding universe within a universe which is already infinite, but you can have an expanding universe within an a priori permittive condition or zero state vacuum.

I still maintain that the universe began as a singularity within a permittive condition (which may be infinite in extent).  But our current universe, while extending (expanding), is not infinite in extent yet. That would pose a contradiction. IMO.

Relative to our spacetime coordinates the universe is infinite. But if it truly was, then where would be the vacuum?

[ Edited: 19 September 2016 04:37 AM by Write4U ]
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Posted: 20 October 2016 03:52 AM   [ Ignore ]   [ # 19 ]
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Write4U - 18 September 2016 04:11 PM

GdB said,
No. First I would not call my posting an analysis: it was more of a statement. And nowhere I implied that ‘infinite space has always existed’, on the contrary.

This is what you said (quote from wiki)

“suggest that the Universe is infinite in extent with a finite age

And this makes the problem easier to solve? It suggests that our universe is already infinite, something which is being debated by the scientific community.

You can lookup your question here: Why does a flat universe imply an infinite universe?

When K < 0 the universe is infinite per definition. However, present empirical observations are that k =1. This means that our global geometry is flat. There are two forms that have a flat geometry: an infinite flat plane, or a torus (think about computer games where an object disappears at the higher border of the screen, appears at the lower. Same for left and right)

The error you make is thinking that the fact that the distances between galaxies globally increase, proves that the universe as a whole is expanding in something else. Your logic is based on everyday objects in the universe, but you cannot treat the universe itself in such a way. You cannot do else than believing what the equations of general relativity tell us. And if the math is too complex for you, you just cannot do else than believe what cosmologists tell you: that the universe seems to be flat, and that it is improbable that it has the form of a torus: until now nobody has seen our galaxy billions of light years away through a telescope.


snap-universe-shape.gif

The closed universe is definitely finite. Both others however are infinite.

But a flat universe can have the form of a torus:

news.2008.854.jpg

The decision is still out. And might stay that way.

PS after writing this I found this article:

Astrophysicists create the first accurate map of the universe: It’s very flat, and probably infinite

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Posted: 20 October 2016 05:16 AM   [ Ignore ]   [ # 20 ]
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GdB - 20 October 2016 03:52 AM
Write4U - 18 September 2016 04:11 PM

GdB said,
No. First I would not call my posting an analysis: it was more of a statement. And nowhere I implied that ‘infinite space has always existed’, on the contrary.

This is what you said (quote from wiki)

“suggest that the Universe is infinite in extent with a finite age

And this makes the problem easier to solve? It suggests that our universe is already infinite, something which is being debated by the scientific community.

You can lookup your question here: Why does a flat universe imply an infinite universe?

When K < 0 the universe is infinite per definition. However, present empirical observations are that k =1. This means that our global geometry is flat. There are two forms that have a flat geometry: an infinite flat plane, or a torus (think about computer games where an object disappears at the higher border of the screen, appears at the lower. Same for left and right)

The error you make is thinking that the fact that the distances between galaxies globally increase, proves that the universe as a whole is expanding in something else. Your logic is based on everyday objects in the universe, but you cannot treat the universe itself in such a way. You cannot do else than believing what the equations of general relativity tell us. And if the math is too complex for you, you just cannot do else than believe what cosmologists tell you: that the universe seems to be flat, and that it is improbable that it has the form of a torus: until now nobody has seen our galaxy billions of light years away through a telescope.


snap-universe-shape.gif

The closed universe is definitely finite. Both others however are infinite.

But a flat universe can have the form of a torus:

news.2008.854.jpg

The decision is still out. And might stay that way.

PS after writing this I found this article:

Astrophysicists create the first accurate map of the universe: It’s very flat, and probably infinite

Thank you GdB, for the follow up and links.  This is a fascinating subject.  I have always visualized a torus shape, which conforms to a lot of known geometric properties and functions.

But do any of the “finite” universal shapes rule out a larger permittive condition which accommodates these closed universes and especially a multiverse?

[ Edited: 20 October 2016 05:35 AM by Write4U ]
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Posted: 20 October 2016 08:04 AM   [ Ignore ]   [ # 21 ]
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Write4U - 20 October 2016 05:16 AM

But do any of the “finite” universal shapes rule out a larger permittive condition which accommodates these closed universes and especially a multiverse?

You are thinking too much about a torus with a 2-D surface in 3-D space. So you think about our universe as a 3-D space in 4-D space. But AFAIK we live in a 3-D space with an additional time dimension. Do not forget: gravity is not the curvature of space, but of spacetime. General Relativity uses internal attributes of spacetime only, e.g. that in curved spacetime angles of a triangle do not add up o 180 degrees. But this does not mean there is something outside this spacetime, in a higher dimension.

It are the analogies with flat planes, surfaces of spheres or tori in our 3-D space that seduce you in thinking there must be something outside. 

Same for the multiverse. Under this heading go very different concepts of ‘other universes’. To imagine them as e.g. spherical universes in a much wider space in which they all expand, is again just some analogy. E.g. it does not apply to the multiple universes as they form in the many worlds interpretation in quantum mechanics.

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Posted: 20 October 2016 02:24 PM   [ Ignore ]   [ # 22 ]
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GdB - 20 October 2016 08:04 AM
Write4U - 20 October 2016 05:16 AM

But do any of the “finite” universal shapes rule out a larger permittive condition which accommodates these closed universes and especially a multiverse?

You are thinking too much about a torus with a 2-D surface in 3-D space. So you think about our universe as a 3-D space in 4-D space. But AFAIK we live in a 3-D space with an additional time dimension. Do not forget: gravity is not the curvature of space, but of spacetime. General Relativity uses internal attributes of spacetime only, e.g. that in curved spacetime angles of a triangle do not add up o 180 degrees. But this does not mean there is something outside this spacetime, in a higher dimension.

It are the analogies with flat planes, surfaces of spheres or tori in our 3-D space that seduce you in thinking there must be something outside. 

Same for the multiverse. Under this heading go very different concepts of ‘other universes’. To imagine them as e.g. spherical universes in a much wider space in which they all expand, is again just some analogy. E.g. it does not apply to the multiple universes as they form in the many worlds interpretation in quantum mechanics.

I stipulate that that my knowledge of cosmology is limited and this is not intended to be an argument but a probing.

But according to CDT (causal dynamical triangulation) itself can curve spacetime as is demonstrated in fractals.

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Posted: 20 October 2016 10:09 PM   [ Ignore ]   [ # 23 ]
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Write4U - 20 October 2016 02:24 PM

I stipulate that that my knowledge of cosmology is limited and this is not intended to be an argument but a probing.

OK, I try to be kind…

Write4U - 20 October 2016 02:24 PM

But according to CDT (causal dynamical triangulation) itself can curve spacetime as is demonstrated in fractals.

I think there is a word missing: what is ‘itself’ referring too? So I do not understand what you are trying to say here. I even doubt you understand it yourself…

CDT at the moment is just one hypothesis about how General Relativity and quantum mechanics can be reconciled. It is not proven.

Why are you so desperately looking for some first principle? Are you missing God, after his passing away?

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Posted: 21 October 2016 07:07 AM   [ Ignore ]   [ # 24 ]
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GdB - 20 October 2016 10:09 PM

CDT at the moment is just one hypothesis about how General Relativity and quantum mechanics can be reconciled. It is not proven.

CDT at least seems based on scientific principles, unlike the many worlds interpretation of quantum mechanics which is pure fantasy.

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Posted: 21 October 2016 10:17 AM   [ Ignore ]   [ # 25 ]
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DarronS - 21 October 2016 07:07 AM

CDT at least seems based on scientific principles, unlike the many worlds interpretation of quantum mechanics which is pure fantasy.

I nearly do not know anything about CDT, but it seems at least that it makes some empirical predictions that might be tested.

However I would not say that the many worlds interpretation of quantum mechanics is pure fantasy: the empirical predictions it makes are correct. But they are not better than the Copenhagen interpretation (ain’t that not the ‘shut up and calculate’ approach?). The many worlds interpretation just tries to keep determinism upright (as the wave function is strictly deterministic). It does that at the cost of a pretty extreme metaphysics.

On the other side, personally I think that the idea that the ‘wave function collapses’ is just another metaphysical monstrosity, which leads to funny philosophies about living and/or dead cats…

I see much more in the decoherence approach, as it has no special role for consciousness, not many worlds, and also not some magical Bohmian quantum potential (sorry, Write4U).

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Posted: 21 October 2016 11:57 AM   [ Ignore ]   [ # 26 ]
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GdB - 21 October 2016 10:17 AM

I see much more in the decoherence approach, as it has no special role for consciousness, not many worlds, and also not some magical Bohmian quantum potential (sorry, Write4U).

Agree 100% on the decoherence hypothesis. If it works decoherence will pave the way for quantum computers. The many worlds postulate predicts nothing, explains nothing, and is not testable.

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Posted: 21 October 2016 05:51 PM   [ Ignore ]   [ # 27 ]
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GdB - 21 October 2016 10:17 AM
DarronS - 21 October 2016 07:07 AM

CDT at least seems based on scientific principles, unlike the many worlds interpretation of quantum mechanics which is pure fantasy.

I nearly do not know anything about CDT, but it seems at least that it makes some empirical predictions that might be tested.

However I would not say that the many worlds interpretation of quantum mechanics is pure fantasy: the empirical predictions it makes are correct. But they are not better than the Copenhagen interpretation (ain’t that not the ‘shut up and calculate’ approach?). The many worlds interpretation just tries to keep determinism upright (as the wave function is strictly deterministic). It does that at the cost of a pretty extreme metaphysics.

On the other side, personally I think that the idea that the ‘wave function collapses’ is just another metaphysical monstrosity, which leads to funny philosophies about living and/or dead cats…

I see much more in the decoherence approach, as it has no special role for consciousness, not many worlds, and also not some magical Bohmian quantum potential (sorry, Write4U).

I also agree on the concept of *decoherence*.  Seems to me that can this can be simply demonstrated in the result of wave-interferences.

The beauty of triangulation is its very simplicity. A triangle is the smallest possible *plane* and if applied 3 dimensionally, it results in dodecahedrons which is another proposed configuration of a finite universe.

CDT goes much deeper and in the abstract is causal to the “unfolding”  (by a process of dynamical iteration) of spacetime itself.
polygon.jpg

Jean-Pierre Luminet of the Observatoire de Paris and colleagues believe that the finite size of the universe itself is responsible for this behaviour. Moreover, they show that the predictions of a model in which space consists of 12 curved pentagons joined together in a sphere agrees with the WMAP observations (figure 2). Their ‘small’, closed universe should be about 30 billion light years across.

http://physicsworld.com/cws/article/news/2003/oct/08/is-the-universe-a-dodecahedron

Visualize a soccer ball., Curved and joined pentagons resulting in a perfectly round sphere. Moreover, the illustration suggests an inherent spiral function.

The main point which makes this concept so attractive is that it is background independent and is compatible with both GR and QM.. And notice the natural spirality of this configuration. The Fibonacci Sequence can be found everywhere we look.

Just a little afterthought: Is it possible that Pi may be an important (causal) aspect in CDT?  A transcendental number which can never reach it’s full potential?

[ Edited: 22 October 2016 12:54 AM by Write4U ]
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Posted: 24 October 2016 02:52 AM   [ Ignore ]   [ # 28 ]
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DarronS - 21 October 2016 11:57 AM

The many worlds postulate predicts nothing, explains nothing, and is not testable.

You seem to be quite irritated about the the many worlds interpretation. wink

I tend to agree with you, however, there is quite a bunch of physicists who somehow take it serious. And it seems that the idea of decoherence arose under MWI adepts… Some of them even believe that, at least in principle, empirical tests would be possible (well, at least according to Wikipedia...)

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Posted: 24 October 2016 02:56 AM   [ Ignore ]   [ # 29 ]
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Write4U,

Such speculations are high above my head, so I haven’t much to say. As once said before: it is fascinating stuff, but we, science amateurs, can just wait and see which theory will float above in a few years. I do not think it is very useful to anticipate some outcome, just while it feels good.

Understanding established Quantum Mechanics and Relativity is already difficult enough…

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Posted: 24 October 2016 09:55 AM   [ Ignore ]   [ # 30 ]
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GdB - 24 October 2016 02:52 AM
DarronS - 21 October 2016 11:57 AM

The many worlds postulate predicts nothing, explains nothing, and is not testable.

You seem to be quite irritated about the the many worlds interpretation. wink

I tend to agree with you, however, there is quite a bunch of physicists who somehow take it serious. And it seems that the idea of decoherence arose under MWI adepts… Some of them even believe that, at least in principle, empirical tests would be possible (well, at least according to Wikipedia...)

Yes, the MWI irritates me. See the Objections section of the wikipedia page you linked for some of the many reasons. The Many Worlds Interpretation is bad science and bad philosophy that relies on special pleadings for its justification.

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