Register | Sign In


Understanding through Discussion


EvC Forum active members: 65 (9162 total)
6 online now:
Newest Member: popoi
Post Volume: Total: 915,817 Year: 3,074/9,624 Month: 919/1,588 Week: 102/223 Day: 13/17 Hour: 0/0


Thread  Details

Email This Thread
Newer Topic | Older Topic
  
Author Topic:   What is "the fabric" of space-time?
randman 
Suspended Member (Idle past 4899 days)
Posts: 6367
Joined: 05-26-2005


Message 16 of 327 (457816)
02-25-2008 5:29 PM
Reply to: Message 14 by New Cat's Eye
02-25-2008 5:17 PM


Catholic, it's a little deeper than that. Cells actually consist of physical properties. What cavediver is saying when he says it consists of "nothing" is that it consists of no matter or energy (defined by physics). Personally, I question stating a field has no energy even if it is a field that has no matter but I recognize what that's problematic for physics (definition of energy must contain matter).
But whatever this consists of, it does give rise to matter. Imo, this is worth thinking about. My word for "nothing" is "immaterial." It's not nothing because we see it's effects and it can be described mathematically, but since it has no matter, it is an immaterial something.

This message is a reply to:
 Message 14 by New Cat's Eye, posted 02-25-2008 5:17 PM New Cat's Eye has replied

Replies to this message:
 Message 18 by New Cat's Eye, posted 02-25-2008 5:51 PM randman has replied

  
randman 
Suspended Member (Idle past 4899 days)
Posts: 6367
Joined: 05-26-2005


Message 17 of 327 (457821)
02-25-2008 5:45 PM
Reply to: Message 14 by New Cat's Eye
02-25-2008 5:17 PM


Emergent properties from one physical system to another so that the sum is greater than the parts is worth discussing. It's not really the thread topic.
But what we are talking about is that physical existence (matter and energy) stems from a non-physical existence or thing.
Edited by randman, : No reason given.

This message is a reply to:
 Message 14 by New Cat's Eye, posted 02-25-2008 5:17 PM New Cat's Eye has not replied

  
New Cat's Eye
Inactive Member


Message 18 of 327 (457823)
02-25-2008 5:51 PM
Reply to: Message 16 by randman
02-25-2008 5:29 PM


Catholic, it's a little deeper than that.
Actually, I think it is deeper than the depth that you think it is.
Cells actually consist of physical properties. What cavediver is saying when he says it consists of "nothing" is that it consists of no matter or energy (defined by physics).
If energy/matter is an emergent property of the field, then what's the problem?
Personally, I question stating a field has no energy even if it is a field that has no matter but I recognize what that's problematic for physics (definition of energy must contain matter).
Think of it as energy being an emergent property of a quantum field. Then the field, itself, doesn't need to have energy.
But whatever this consists of, it does give rise to matter. Imo, this is worth thinking about. My word for "nothing" is "immaterial."
Immaterial, to me, means that it just lacks mass.
Light is immaterial, but it isn't nothing.
It's not nothing because we see it's effects and it can be described mathematically but since it has no matter, it is an immaterial something.
Well, if you want to use the word 'immaterial', then go right ahead.

This message is a reply to:
 Message 16 by randman, posted 02-25-2008 5:29 PM randman has replied

Replies to this message:
 Message 19 by randman, posted 02-25-2008 5:55 PM New Cat's Eye has replied

  
randman 
Suspended Member (Idle past 4899 days)
Posts: 6367
Joined: 05-26-2005


Message 19 of 327 (457824)
02-25-2008 5:55 PM
Reply to: Message 18 by New Cat's Eye
02-25-2008 5:51 PM


If energy/matter is an emergent property of the field, then what's the problem?
There is no problem. Just pointing out the "field" as you say has no energy or matter. Energy and matter originate from an immaterial state.
Immaterial, to me, means that it just lacks mass.
Light is immaterial, but it isn't nothing.
Light is not immaterial. Maybe you aren't getting the concept here?

This message is a reply to:
 Message 18 by New Cat's Eye, posted 02-25-2008 5:51 PM New Cat's Eye has replied

Replies to this message:
 Message 20 by New Cat's Eye, posted 02-25-2008 5:57 PM randman has replied

  
New Cat's Eye
Inactive Member


Message 20 of 327 (457826)
02-25-2008 5:57 PM
Reply to: Message 19 by randman
02-25-2008 5:55 PM


There is no problem. Just pointing out the "field" as you say has no energy or matter. Energy and matter originate from an immaterial state.
So what?
Light is not immaterial. Maybe you aren't getting the concept here?
Maybe not. Please enlighten me.

This message is a reply to:
 Message 19 by randman, posted 02-25-2008 5:55 PM randman has replied

Replies to this message:
 Message 21 by randman, posted 02-25-2008 6:20 PM New Cat's Eye has replied

  
randman 
Suspended Member (Idle past 4899 days)
Posts: 6367
Joined: 05-26-2005


Message 21 of 327 (457830)
02-25-2008 6:20 PM
Reply to: Message 20 by New Cat's Eye
02-25-2008 5:57 PM


Light consists of photons. Photons are particles and have energy. We were talking of what gives rise to particles, mass and energy, not emergent properties after that occurs.

This message is a reply to:
 Message 20 by New Cat's Eye, posted 02-25-2008 5:57 PM New Cat's Eye has replied

Replies to this message:
 Message 22 by New Cat's Eye, posted 02-25-2008 6:58 PM randman has replied

  
New Cat's Eye
Inactive Member


Message 22 of 327 (457839)
02-25-2008 6:58 PM
Reply to: Message 21 by randman
02-25-2008 6:20 PM


Light consists of photons. Photons are particles and have energy.
What I said in Message 18 is:
quote:
Immaterial, to me, means that it just lacks mass.
Light is immaterial, but it isn't nothing.
What I was saying is that light doesn't have (rest) mass so by some definitions it can be called immaterial. Its a small point, but I think that is a better definition than immaterial means "nothing".
quote:
immaterial
adjective
1. of no importance or relevance especially to a law case; "an objection that is immaterial after the fact" [ant: material]
2. without material form or substance; "an incorporeal spirit" [syn: incorporeal] [ant: corporeal]
3. not consisting of matter; "immaterial apparitions"; "ghosts and other immaterial entities" [ant: material]
4. not pertinent to the matter under consideration; "an issue extraneous to the debate"; "the price was immaterial"; "mentioned several impertinent facts before finally coming to the point" [syn: extraneous]
5. (often followed by 'to') lacking importance; not mattering one way or the other; "whether you choose to do it or not is a matter that is quite immaterial (or indifferent)"; "what others think is altogether indifferent to him"
From here.
We were talking of what gives rise to particles, mass and energy, not emergent properties after that occurs.
And what gives rise to particles, mass and energy is not made up of particles, mass and energy. They come from quantum fields.
Like I was originally saying, you could think of particles, mass and energy as emergent properties of the quantum field.
My position is both veracious and consistent, so can we move forward now?
Where we left off was me asking:
quote:
There is no problem. Just pointing out the "field" as you say has no energy or matter. Energy and matter originate from an immaterial state.
So what?

This message is a reply to:
 Message 21 by randman, posted 02-25-2008 6:20 PM randman has replied

Replies to this message:
 Message 26 by randman, posted 02-26-2008 12:19 AM New Cat's Eye has replied

  
Calypso
Junior Member (Idle past 5155 days)
Posts: 28
Joined: 06-05-2006


Message 23 of 327 (457847)
02-25-2008 7:50 PM
Reply to: Message 8 by cavediver
02-25-2008 2:59 PM


What are these layers/fields made of? They're not made of anything - they are the underlying reality - everything else is made from, or is an aspect of, these fields. However, they are very familiar - they seem to be objects that we know very well from pure mathematics. Now why should that be...?
Hmm you lost me there I think. Objects that we know from mathematics? Is not mathematics just the language we use to describe what we see out in the universe? So I would think we know these objects from mathematics because we invented mathematics to describe what we see happening in the real world. Correct me if I'm wrong.
Are you asking why they fit a mathematical model so well? Did we not come up with that mathematical model to fit our observations rather than the other way around? Or did I misunderstand what you meant by that question? If so please expound on it if you could? It intrigues me and probably because I think I do not understand it, or what you meant by it.
Also when you said "They're not made of anything - they are the underlying reality - everything else is made from" My question to that would be so mass is warping nothing? How can you warp nothing? I'm having a hard time understanding this concept. I would think if there is nothing there, then there is nothing to be warped or deformed. As far as I see it, mass is warping something is it not?

This message is a reply to:
 Message 8 by cavediver, posted 02-25-2008 2:59 PM cavediver has not replied

Replies to this message:
 Message 24 by fallacycop, posted 02-25-2008 8:49 PM Calypso has not replied

  
fallacycop
Member (Idle past 5520 days)
Posts: 692
From: Fortaleza-CE Brazil
Joined: 02-18-2006


Message 24 of 327 (457854)
02-25-2008 8:49 PM
Reply to: Message 23 by Calypso
02-25-2008 7:50 PM


As far as I see it, mass is warping something is it not?
mass warps space

This message is a reply to:
 Message 23 by Calypso, posted 02-25-2008 7:50 PM Calypso has not replied

Replies to this message:
 Message 25 by Chiroptera, posted 02-25-2008 9:09 PM fallacycop has not replied
 Message 60 by Buzsaw, posted 03-01-2008 4:53 PM fallacycop has replied

  
Chiroptera
Inactive Member


Message 25 of 327 (457855)
02-25-2008 9:09 PM
Reply to: Message 24 by fallacycop
02-25-2008 8:49 PM


To be more precise, space-time is a manifold - that is, it is a four dimensional object that has a certain shape. The fact that the shape isn't completely flat is what we call "warped". This "warping" of space-time -- the fact that in places it is very much not flat -- is what we experience as "mass".
Mass doesn't warp space-time. Rather, mass is the warps in space-time.

If I had a million dollars, I'd buy you a monkey.
Haven't you always wanted a monkey?
-- The Barenaked Ladies

This message is a reply to:
 Message 24 by fallacycop, posted 02-25-2008 8:49 PM fallacycop has not replied

Replies to this message:
 Message 27 by Calypso, posted 02-26-2008 1:41 AM Chiroptera has replied

  
randman 
Suspended Member (Idle past 4899 days)
Posts: 6367
Joined: 05-26-2005


Message 26 of 327 (457867)
02-26-2008 12:19 AM
Reply to: Message 22 by New Cat's Eye
02-25-2008 6:58 PM


So what in your view does the quantum field consist of?
Cavediver makes an interesting statement, namely that energy and mass arise from something that has no energy and mass. Photons have energy. Photons arise from this something other.
What is it?

This message is a reply to:
 Message 22 by New Cat's Eye, posted 02-25-2008 6:58 PM New Cat's Eye has replied

Replies to this message:
 Message 28 by New Cat's Eye, posted 02-26-2008 10:08 AM randman has replied

  
Calypso
Junior Member (Idle past 5155 days)
Posts: 28
Joined: 06-05-2006


Message 27 of 327 (457881)
02-26-2008 1:41 AM
Reply to: Message 25 by Chiroptera
02-25-2008 9:09 PM


To be more precise, space-time is a manifold - that is, it is a four dimensional object that has a certain shape. The fact that the shape isn't completely flat is what we call "warped". This "warping" of space-time -- the fact that in places it is very much not flat -- is what we experience as "mass".
Mass doesn't warp space-time. Rather, mass is the warps in space-time.
I've heard it said like this: Mass tells space how to curve, space tells mass how to move,
Or something like that. I'm paraphrasing but this would mean mass does warp space. So is this not correct?

This message is a reply to:
 Message 25 by Chiroptera, posted 02-25-2008 9:09 PM Chiroptera has replied

Replies to this message:
 Message 29 by New Cat's Eye, posted 02-26-2008 10:15 AM Calypso has not replied
 Message 30 by Chiroptera, posted 02-26-2008 10:46 AM Calypso has not replied

  
New Cat's Eye
Inactive Member


Message 28 of 327 (457910)
02-26-2008 10:08 AM
Reply to: Message 26 by randman
02-26-2008 12:19 AM


So what in your view does the quantum field consist of?
I don't think that it "consists" of "stuff". It is pre-stuffs.
It is a very complicated field and I don't feel capable of explaining it to you.
How much do you know about fields?
Do you know Calculus?
What about Algebraic Geometry?
Somebody can't just come in here and say: "The quantum field consists of blah blah blah...."
You have to understand the math and some pretty difficult concepts to begin to understand, or spout, the descriptions of what a quantum field is.

This message is a reply to:
 Message 26 by randman, posted 02-26-2008 12:19 AM randman has replied

Replies to this message:
 Message 31 by randman, posted 02-26-2008 10:50 AM New Cat's Eye has replied

  
New Cat's Eye
Inactive Member


Message 29 of 327 (457911)
02-26-2008 10:15 AM
Reply to: Message 27 by Calypso
02-26-2008 1:41 AM


I'm paraphrasing but this would mean mass does warp space. So is this not correct?
A tidal wave is a warp in the ocean, so does the ocean warp waves?

This message is a reply to:
 Message 27 by Calypso, posted 02-26-2008 1:41 AM Calypso has not replied

  
Chiroptera
Inactive Member


Message 30 of 327 (457920)
02-26-2008 10:46 AM
Reply to: Message 27 by Calypso
02-26-2008 1:41 AM


This is an interesting question.
Disclaimer: I do not have any real experience with GR. From the physics side of my education, GR requires a knowledge of differential geometry, which is not part of the standard curriculum for physics students even at the graduate level. It is mostly those students who are specializing in GR who end up studying it.
On the math side, I did take a course in differential geometry. But I never really got an intuitive feel for what a non-positive definite metric "looks like" (I can "visualize" an n-manifold with a positive definite metric), nor did I ever see physics applications. So, my "explanation" is going to consist of what I understand from the math side.
Manifolds automatically come already curved. In fact, it is how the manifolds are curved that distinguishes them. The curvature is basically the shape. The only significant difference between a sphere and an oblate ellipsoid is that the curvatures are different. If I hand you a sphere, it is already curved -- that is what makes it a sphere.
So, when our universe is modelled by a Lorentzian 4-manifold, it has to come with some shape. In the physical GR model, mass density is a parameter (or one of several parameters) that is part of the mathematical equations that describe the curvature.
Now the interesting question is: is there some physical quality called mass that forces the otherwise flat manifold to curve? Or is does the manifold already come curved, and our experience of mass simply how we percieve this curvature? This becomes a metaphysical question, about how exactly we are going to interpret the mathematical equations to make sense of what we actually observe.
But in the end that's all we have: the mathematical models, a way of interpreting the results of calculations in terms of potential observations, and some measure of how close the potential observations match up with our actual observations. The actual ontological nature of the universe is, I suspect, beyond what science can really answer.

If I had a million dollars, I'd buy you a monkey.
Haven't you always wanted a monkey?
-- The Barenaked Ladies

This message is a reply to:
 Message 27 by Calypso, posted 02-26-2008 1:41 AM Calypso has not replied

  
Newer Topic | Older Topic
Jump to:


Copyright 2001-2023 by EvC Forum, All Rights Reserved

™ Version 4.2
Innovative software from Qwixotic © 2024