What is the fabric of the universe?

In summary: Just a thought...In summary, gravity is a force or field that affects space-time and is responsible for the propagation of objects through spacetime.
  • #1
petm1
399
1
I just wanted to know what people think of the question "What is the fabric of the universe?" I only see two choices either time or space. I know that gravity is something that warps space, which means it must warp the fabric of space, or our second choice time, and I would think that any theory of gravity must at the very least contain a quantum theory of time, because imho gravity is a function of time not space. What do you think?
 
Astronomy news on Phys.org
  • #2
petm1 said:
I just wanted to know what people think of the question "What is the fabric of the universe?" I only see two choices either time or space.
Why not both?
petm1 said:
I know that gravity is something that warps space, ...
... and time!

See links in https://www.physicsforums.com/showpost.php?p=1557122&postcount=4"
 
Last edited by a moderator:
  • #3
The fabric of the universe is indeed BOTH space and time.

We call it space-time.

And then gravity warps space-time.
 
  • #4
I started this thread thinking that the fabric was either time, space, or space-time. Maybe I should have started it as a poll and listed "other" as a choice, because after thinking of my own question I would have to change my answer to light as being the fabric, with the photon as the thread and matter the ball of yarn. That would make space the loom, time the the room, and you can believe in any weaver that you want. Sorry if this seems to simple but it made me smile when I thought of it.
 
Last edited:
  • #5
The best discussion of this issue----where we are at present on it-----that I know of is in the survey paper by Renate Loll called
Quantum Gravity on your Desktop


time and space are largescale perceptions that emerge from some more fundamental processes at microscopic level. Because of Heisenberg Uncertainty, the smaller scale you look the more chaotic spacetime geometry is likely to be. It may not even have a well defined dimensionality down near or below Planck scale. Concepts like length area volume angle may be infected with indeterminacy just as in ordinary quantum mechanics the position and momentum of a particle are not completely determined.

Smooth space and regular time may be illusions which appear at a macroscopic scale, emerging from a microscopic reality which is not so smooth and regular.

Quantum gravity teaches us to expect this. Wheeler (a great physicist of the last century) used to refer to the "spacetime foam".

Among presentday researchers, I think Loll's group is as advanced as any. They are not saying what is there but they are running some pretty good simulations of small universes. have some pretty reasonable conjectures.

Google "renate loll" and see if you can find that recent article at her website.
 
  • #6
gravity is an extra dimension, above time and the three dimensions of space
 
  • #7
No time is an extra dimension, not gravity. Gravity is a force or field, and is not a dimension.
 
  • #8
If gravity were to be a dimension then wouldn't we experience fluctuation of gravity in different reference frames?!
-ibysaiyan
 
  • #9
Yes. We could go on and on on why gravity is not a dimension.
 
  • #10
Gravity makes a good fabric for the universe without it we would never have found evidence of black holes, you've got to love general relativity.
 
  • #11
petm1 said:
Gravity makes a good fabric for the universe without it we would never have found evidence of black holes, you've got to love general relativity.

I don't think gravity can be considered the "fabric" of the universe. More like the fat lady sitting on the fabric having a picnic.
 
  • #12
Hah, that made me laugh quite hard. Well, it doesn't have to be a fat lady, basically its anything sitting on the fabric, of any size. But I understand what you meant by that post.
 
  • #13
Drakkith said:
I don't think gravity can be considered the "fabric" of the universe. More like the fat lady sitting on the fabric having a picnic.
Cite some references. I totally disagree.
 
  • #14
Gravity is much better described as a force upon said "fabric" rather than a constituent of the "fabric" itself. Gravity has an effect upon space-time which would explain why gravity has been shown to travel in excess of light-speed. just as a pull on a non-stretchable object wrapped around the equator would show instantaneous movement on both ends. Gravitational propagation would occur as a dependency of the amount of "Stretch" present in space-time itself.
 
  • #15
Gravity does not travel FTL. It propagates at c. An object wrapped around the equator, when pulled, would react at the speed that sound propagates through the material.
 
  • #16
Chronos said:
Cite some references. I totally disagree.

Interesting this Chronos. Gravity must have propogated through all of spacetime. Could geometry or curvature be the fabric of reality, that seems reasonable to me, everything is anchored geometrically to the Universe. Curvature is king! :)

Not a personal theory just an idea.

Has made me think though, geometry and therefore gravity and curvature are present everywhere, even if curvature is 0 it can still be explained mathematically.

All really interesting. :smile:
 
  • #17
r73826779 said:
Gravity is much better described as a force upon said "fabric" rather than a constituent of the "fabric" itself. Gravity has an effect upon space-time which would explain why gravity has been shown to travel in excess of light-speed. just as a pull on a non-stretchable object wrapped around the equator would show instantaneous movement on both ends. Gravitational propagation would occur as a dependency of the amount of "Stretch" present in space-time itself.

Both of the bolded statements are nonsense, as Drakkith has already pointed out (although more politely than me). You really should read up on basic physics before you make such pronouncements on a physics forum.
 
  • #18
Cosmo Novice said:
Interesting this Chronos. Gravity must have propogated through all of spacetime. Could geometry or curvature be the fabric of reality, that seems reasonable to me, everything is anchored geometrically to the Universe. Curvature is king! :)

Depends on what you mean by "Fabric of reality".
 
  • #19
Is it just my concept of semantics, or would we, as I believe, all be better off if no one EVERY used the term "fabric" in conjunction with spacetime, but rather used "structure" or some similar concept. "Fabric" carries over unfortunate connotations from standard English.
 
  • Like
Likes Jenorah
  • #20
Agreed phinds.
 
  • #21
When I read about space-time and gravity, the idea I get is that gravity isn't really a "force" when you look at it from the perspective of space-time. It's just an apparent attractive force between two objects of mass. Objects of mass distort the shape of space-time and this distortion causes us to feel the apparent force of gravity.

That's why I'd say that space-time is the "fabric" of reality, because we are sort of sitting in it and "rolling" around in it like the marbles in the bowl with the orange at the bottom.
 
  • #22
phinds said:
Is it just my concept of semantics, or would we, as I believe, all be better off if no one EVERY used the term "fabric" in conjunction with spacetime, but rather used "structure" or some similar concept. "Fabric" carries over unfortunate connotations from standard English.

Yes I think you are right - just wanted to keep in line with the OP. When I say fabric I mean underlying structure which I think does not carry so many obvious connotations.

So to rephrase, IMO geometry is the underlying structure of the Universe - geometry exists in absolute vacuum, so the vacuum requires geometry, it exists in mass and around mass, geometry even exists in Black Holes (at least in terms of extreme curvature.) All a bit mind bending and also kind of philosophical in quantifying these things. Anyway I am musing now with little positive results so I will cease!
 
  • #23
Once you hit or run through the surface of Outer space, a thing that's never been touched before, doesn't itconsistantly change what it has been doing so far?It sure would explain the speedy satellite thing...And i agree with Marcus, i think the universe is made up of a bunch of Big peices of Matter, not some small micromollecular material..
Itsonly going to be enough for us to handle if we can step up and callit ours..Ω
 
  • #24
Do any of you believe in a place outside of the Fabrics of space?
Light,Matter,more or less space,Another universe,another'Galaxy' past the darkness of the Vaccum,so tospeak?
Obviously its to say we would truly be able to take or universe and stick in under a microscope,but come on, give me some Real ideas, i want to explore This,blindly
Today right now, some of you guys got to think,What is your part in all this
Because its not even what the answers are that matters,it just that we know they could very well exist.We haven't just been obsessing for Eons..Only a few century's,enough for this Species to coincide on what we reallly believe in??
Call me the physics Hippie;)
 
Last edited:
  • #25
Ryan_wazhere said:
Once you hit or run through the surface of Outer space, a thing that's never been touched before, doesn't itconsistantly change what it has been doing so far?It sure would explain the speedy satellite thing...And i agree with Marcus, i think the universe is made up of a bunch of Big peices of Matter, not some small micromollecular material..
Itsonly going to be enough for us to handle if we can step up and callit ours..Ω

I'm sorry, I can't understand what you are saying or asking here. It doesn't seem to follow any of the normal terminology of physics.

Ryan_wazhere said:
Do any of you believe in a place outside of the Fabrics of space?
Light,Matter,more or less space,Another universe,another'Galaxy' past the darkness of the Vaccum,so tospeak?

What is the "Darkness of the Vacuum"?

Obviously its to say we would truly be able to take or universe and stick in under a microscope,but come on, give me some Real ideas, i want to explore This,blindly
Today right now, some of you guys got to think,What is your part in all this
Because its not even what the answers are that matters,it just that we know they could very well exist.We haven't just been obsessing for Eons..Only a few century's,enough for this Species to coincide on what we reallly believe in??
Call me the physics Hippie;)

What? I can't understand anything about what you're trying to get across.
 
  • #26
Drakith +1, this seems to be just strings of words with no meaning in physics.
 
  • #27
It's just another way of asking if there is anything 'outside' our universe. Logic and semantical issues aside, efforts to determine if the universe is finite or infinite are an active area of interest in cosmology.
 
  • #28
petm1 said:
I know that gravity is something that warps space, which means it must warp the fabric of space

I don't think I would use ''...something that warps space...'' here. As I understand it, and maybe I am wrong, gravity doesn't warp spacetime. Mass does, and those warps themselves are what we call gravity.
 
  • #29
Of course there is no specific answer widely agreed upon answer regarding a 'fabric'. Why would one suppose that the 'fabric of the universe' is limited to space and time.


I like Marcus' post #5 and would add that all of the universe we observe, and likely lots more, somehow originated maybe from 'nothing', at a big bang...unless you subscribe to a cyclic universe model. In any case, it doesn't appear that the forces nor energy, for example, should be excluded from consideration of a such a 'fabric'.

Seems as likely as not to me that whatever is in the vacuum may well form the unified basis for all the apparently distinct phenomena we can't quite figure out yet...like the energy of the vacuum that drives cosmological expansion.
 
  • #30
IMO Time doesn't have a beginning. I mean, how can you start time? It must have always existed, and truthfully what is time anyway? I see time as simply the motion of the universe. So if Time is infinite, then that would assume that space is also infinite. Imagine something expanding and growing for eternity, what would that look like? How many dimensions would it cross? It's like that old computer game called "Life", but imagine it continues to grow, and eventually takes on new forms and those forms again grow into something else. The patterns would continue to infinite complexity.
 
  • #31
petm1 said:
I just wanted to know what people think of the question "What is the fabric of the universe?" I only see two choices either time or space. I know that gravity is something that warps space, which means it must warp the fabric of space, or our second choice time, and I would think that any theory of gravity must at the very least contain a quantum theory of time, because imho gravity is a function of time not space. What do you think?

The Milky Way's halo is what is referred to as the curvature of spacetime.
 
  • #32
nai1ed said:
IMO Time doesn't have a beginning. I mean, how can you start time? It must have always existed, and truthfully what is time anyway? I see time as simply the motion of the universe. So if Time is infinite, then that would assume that space is also infinite. Imagine something expanding and growing for eternity, what would that look like? How many dimensions would it cross? It's like that old computer game called "Life", but imagine it continues to grow, and eventually takes on new forms and those forms again grow into something else. The patterns would continue to infinite complexity.

Saying time can't have a beginning makes no more or less sense than saying it can.

ideal_fluid said:
The Milky Way's halo is what is referred to as the curvature of spacetime.

Not true. See the following article:
http://en.wikipedia.org/wiki/Milky_way#Halo
 
  • #33
Drakkith said:
Not true. See the following article:
http://en.wikipedia.org/wiki/Milky_way#Halo

I'm not referring to the particles of matter which exist in the halo. I'm referring to the halo itself.

http://en.wikipedia.org/wiki/Milky_way#Halo

"the Milky Way Galaxy is embedded with a large amount of hot gas in the halo"

The particles of matter which the hot gas consists of exist "in the halo".

The halo is curved spacetime.
 
Last edited:
  • #34
ideal_fluid said:
The halo is curved spacetime.

I don't see how you are reaching this conclusion. Space-time curvature exists everywhere, as that is what gravity is. The halo is not made up of curved space-time. It is made up of matter in the form of stars and gas, and probably a large amount of dark matter as well.
 
  • #35
Drakkith said:
I don't see how you are reaching this conclusion. Space-time curvature exists everywhere, as that is what gravity is. The halo is not made up of curved space-time. It is made up of matter in the form of stars and gas, and probably a large amount of dark matter as well.

Space itself has a fluidic nature. Matter is moving through space. What is mistaken to be non-baryonic dark matter anchored to matter is the state of the space connected to and neighboring massive objects.

'Hubble Finds Ghostly Ring of Dark Matter'
http://www.nasa.gov/mission_pages/hubble/news/dark_matter_ring_feature.html

"Astronomers using NASA's Hubble Space Telescope got a first-hand view of how dark matter behaves during a titanic collision between two galaxy clusters. The wreck created a ripple of dark mater, which is somewhat similar to a ripple formed in a pond when a rock hits the water."

The 'pond' is the fluidic nature of space itself. The ripple is a wave in space. The ripple is a gravitational wave.

'Galactic Pile-Up May Point to Mysterious New Dark Force in the Universe'
http://www.wired.com/wiredscience/2013/01/musket-ball-dark-force/

"The reason this is strange is that dark matter is thought to barely interact with itself. The dark matter should just coast through itself and move at the same speed as the hardly interacting galaxies. Instead, it looks like the dark matter is crashing into something — perhaps itself – and slowing down faster than the galaxies are. But this would require the dark matter to be able to interact with itself in a completely new an unexpected way, a “dark force” that affects only dark matter."

It's not a new force. It's the fluidic nature of space itself each of the galaxy clusters are interacting with analogous to the bow waves of two boats which pass by each other.

'Offset between dark matter and ordinary matter: evidence from a sample of 38 lensing clusters of galaxies'
http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.1475v1.pdf

"Our data strongly support the idea that the gravitational potential in clusters is mainly due to a non-baryonic fluid, and any exotic field in gravitational theory must resemble that of CDM fields very closely."

The offset is due to the galaxy clusters moving through the fluidic nature of space itself. The analogy is a submarine moving through the water. You are under water. Two miles away from you are many lights. Moving between you and the lights one mile away is a submarine. The submarine displaces the water. The state of displacement of the water causes the center of the lensing of the light propagating through the water to be offset from the center of the submarine itself. The offset between the center of the lensing of the light propagating through the water displaced by the submarine and the center of the submarine itself is going to remain the same as the submarine moves through the water. The submarine continually displaces different regions of the water. The state of the water connected to and neighboring the submarine remains the same as the submarine moves through the water even though it is not the same water the submarine continually displaces. This is what is occurring physically in nature as the galaxy clusters move through space.

'Surprise! IBEX Finds No Bow ‘Shock’ Outside our Solar System'
http://www.universetoday.com/95094/surprise-ibex-finds-no-bow-shock-outside-our-solar-system/

'“While bow shocks certainly exist ahead of many other stars, we’re finding that our Sun’s interaction doesn’t reach the critical threshold to form a shock,” said Dr. David McComas, principal investigator of the IBEX mission, “so a wave is a more accurate depiction of what’s happening ahead of our heliosphere — much like the wave made by the bow of a boat as it glides through the water.”'

The wave ahead of our heliosphere is state of the space connected to and neighboring the solar system.

Curved spacetime is the state of the space connected to and neighboring massive objects. This is what the Milky Way's halo is.
 
Last edited:
Back
Top