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Author Topic:   What is "the fabric" of space-time?
cavediver
Member (Idle past 2879 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 211 of 327 (461034)
03-21-2008 12:47 PM
Reply to: Message 210 by 2ice_baked_taters
03-21-2008 12:14 PM


sigh

I suppose I should shut up and seek your suggested reading material.

Yep


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johnfolton 
Suspended Member (Idle past 4827 days)
Posts: 2024
Joined: 12-04-2005


Message 212 of 327 (461037)
03-21-2008 1:08 PM
Reply to: Message 208 by cavediver
03-21-2008 8:20 AM


Forget about all the books on string theory, M-theory, branes, and all that bollocks. It is pointless trying to learn about this without a grasp of the fundementals.

Not saying fundementals are not important but simply don't feel string theory is bollocks. I suspect fields are the direct result of strings that dark energy is increasing nothingness(space) giving rise to space time incuding new energy coming into existence.

If Einstein is correct then energy is created when space expands if so then does this mean the reverse true that energy can cease to exists if space would shrink (contract).

If true then would not all things simply be destroyed if space would contract back to t=0 to nothingness. If energy is created then the entire universe would contract back to t=0 then nothingness would be at a state of rest with no energy existing at t=0. Is Einstein correct that space has special properties that nothing can be expanded giving rise to energy. If so does this helps explain how dimensions such as time are created?

P.S. If dark energy dark matter is not of this universe it would still exists because its apart from the expansion though according to NASA responsible for the expansion, etc...

Wondering if physics is hung up on less than 5% of the universe, meaning are they discounting over 95 % of the stuff in the universe? etc...So string theory stuff including dark matter is expanding on GR and quantum mechanics to include stuff outside the less than 5 % stuff of the universe.

P.S. Its been said that Einstein said space can expand and create energy thus the reverse must be true yet were told energy can not be created nor destroyed. NASA has said dark energy (God?) is responsible for the expansion so is it not the force believed responsible for the creation of energy.


Albert Einstein was the first person to realize that empty space is not the same as nothingness. Space has amazing properties, many of which are just beginning to be understood. The first property of space that Einstein discovered is that it is possible for more space to come into existence. One version of Einstein's gravity theory makes a second prediction: "empty space" can possess its own energy. This energy would not be diluted as space expands, because it is a property of space itself; as more space came into existence, more of this energy-of-space would come into existence as well.

What is Dark Energy?

We don't know. We know how much there is, and we know some of the properties it must have. Other than that, dark energy is a mystery, and it's important that we find out more. Roughly 70% of the universe is made of dark energy. Dark matter makes up about 25%. Everything on Earth, everything that we have ever observed with all of our instruments – normal matter – adds up to less than 5% of the universe. Then again, maybe we shouldn't even continue call it "normal" matter since it's just a small fraction of the universe!

http://science.hq.nasa.gov/universe/science/dark_energy.html

Edited by johnfolton, : No reason given.


This message is a reply to:
 Message 208 by cavediver, posted 03-21-2008 8:20 AM cavediver has replied

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cavediver
Member (Idle past 2879 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 213 of 327 (461043)
03-21-2008 2:45 PM
Reply to: Message 212 by johnfolton
03-21-2008 1:08 PM


Not saying fundementals are not important but simply don't feel string theory is bollocks.

As an ex-'string theorist', neither do I feel that string theory is bollocks. But harping on about string theory, without a grasp of the fundementals IS bollocks.

I suspect fields are the direct result of strings that dark energy is increasing nothingness(space) giving rise to space time incuding new energy coming into existence.

Ahem...

Edited by cavediver, : No reason given.


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Fabric
Member (Idle past 4908 days)
Posts: 41
From: London, England
Joined: 02-27-2005


Message 214 of 327 (461763)
03-27-2008 5:43 PM


What is a derived property ?

For example space is not energy because energy is a derived property, but as
stated i dont understand what it means.

Or does it mean that energy is made out of something else so it is not space because it's energy ?

Or energy is a derived concept, what does this term mean please as i
don't understand it.

Cheers

Edited by Fabric, : adding derived concept part


Myspace!

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john6zx
Member (Idle past 4057 days)
Posts: 66
Joined: 01-27-2007


Message 215 of 327 (461810)
03-27-2008 9:41 PM
Reply to: Message 3 by Organicmachination
02-25-2008 12:55 AM


Re: Fabric of Space-Time
ORGANICMACHINATION, you said in post # 3 the following:

“The three dimensions of space and the one dimension of time are intertwined and form a smooth fabric, what we call the fabric of space-time. Gravitation is caused by the presence of matter on this fabric. Consider a bowling ball on a taught rubber sheet. When the ball is placed on the sheet, the sheet bends downward, and the ball sinks. Now, a coin or another ball dropped on the edge of this hole starts falling inwards. This is how gravity works. Any star or planet or anything bends space-time downwards, and gravity is us falling down that slop to the bottom of the pit.”

After reading a post like this I have to wonder what scientific references you are referring to. It seems that you have taken the liberty of adding statements that are a bit embellished. For example;

1. “Three dimensions of space and one dimension of time are intertwined”

Get your hands on a good dictionary and define the words DIMENSION, SPATIAL DIMENSION, SPACE, TIME. There is no standard definition or reference that states that any of the above terms describe actual real physical things. So there could be no actual physical combining of these things.

2. “The three dimensions of space and the one dimension of time are intertwined and form a smooth fabric, “

Smooth fabric? Has anyone seen, let alone touched this “fabric”? How does anyone know that this fabric is smooth?

3. “Gravitation is caused by the presence of matter on this fabric. Consider a bowling ball on a taught rubber sheet. When the ball is placed on the sheet, the sheet bends downward, and the ball sinks. Now, a coin or another ball dropped on the edge of this hole starts falling inwards. This is how gravity works. Any star or planet or anything bends space-time downwards, and gravity is us falling down that slop to the bottom of the pit.”

What is pulling this matter down into the fabric? Why would matter move in a downward direction? If gravity is not the responsible force, then what is?

You say that the above statement #3 is how gravity works. All the above statement says is gravity will pull things down against this thing that is supposed to be made of two human concepts, time and space. There is no explanation of what gravity is in your original post.

Again grab a good dictionary and start clearing up your misunderstood terms.


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john6zx
Member (Idle past 4057 days)
Posts: 66
Joined: 01-27-2007


Message 216 of 327 (461814)
03-27-2008 10:21 PM
Reply to: Message 200 by 2ice_baked_taters
03-18-2008 8:52 PM


We do not speak of the fabric of speed/distance.
Why would we treat space/time differently?
"Space" according the the latest fermi lab testing is comprised of neutrinos.

If space is made of neutrinos then what is between these neutrinos? More neutrinos? And on and on it goes, more neutrinos making up more space between neutrinos. When does it stop?

Does this discription of space sound O.K. to you? Why must science try to make the idea of space more than it is. The scientific community does not dispute any of the definitions of space in standard dicitionaries, which make the statement that space is a measurement of distance, or is an area between objects. No definitions claim space to be a physical thing. Yet the scientific community has an idea that space is a real physical thing. Makes one wonder if they even look around them and decide what the term space is really. If space is a thing, it would have to exist in a location, thereby making it more of an object that exists in something. And so then these guys would try to find out what SPACE is existing in. Round and round they go.


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Organicmachination
Member (Idle past 4946 days)
Posts: 105
From: Pullman, WA, USA
Joined: 12-30-2007


Message 217 of 327 (461815)
03-27-2008 10:45 PM
Reply to: Message 215 by john6zx
03-27-2008 9:41 PM


Re: Fabric of Space-Time
First of all, don't try and tell me to use a dictionary to define what I'm talking about. The definitions one will find in a dictionary are not scientific definitions. They are general ones defining general concepts known to laymen. When cosmologists talk about space-time, they don't mean what you think they mean. They don't mean the space between objects exactly. The "fabric" of space-time is a mathematical object, which, although not tangible, is seen in mathematical models of gravitation and quantum mechanics. You should look up these mathematical concepts yourself so that you can better understand them and know them before you try and argue against them.

Second, nothing is pulling the matter down the fabric of space-time. Matter and energy can only exist on the fabric itself, and so when it is curved by the mass of things like stars and galaxies, matter and energy have no choice but to follow that curve. Again, the fabric is a mathematical model that explains everything we see. Don't argue against it until you understand it.

And "time" and "space" are not human made concepts, but are aspects of the natural world. They are as much human made concepts as diffusion is a human made law. Scientists seek only to explain these concepts by using models, the "fabric" of which I speak being one of those.

You seem to be coming into this debate with as much knowledge of the concept as a city boy has knowledge of farming. You only know what you hear from other people and what you choose to believe. Before you come in here trying to debunk a standard explanation of gravity, try and understand what the explanation is saying instead of viewing it through warped and clouded eyes.


This message is a reply to:
 Message 215 by john6zx, posted 03-27-2008 9:41 PM john6zx has replied

Replies to this message:
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lyx2no
Member (Idle past 3952 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


Message 218 of 327 (461830)
03-28-2008 1:36 AM
Reply to: Message 216 by john6zx
03-27-2008 10:21 PM


2Ice baked taters is wrong about Fermi Lab claiming space was comprised of neutrinos. They may have stated space was stuffed cheek to jowl with neutrinos, but not made of them

Science doesn't try to make the idea of space more that it is; it tries to define it.

Space is physical. It's what things are in. Space isn't in anything: It's space.

Yes, scientists look around themselves all the time. One might even say it's their job.

Round and round they go.

Actually, round and round you go. Your confusion is not ours.

And while we're at it, you might want to try learning physics from a physics book rather than a dictionary.


Kindly

∞∞∞∞

When I was a child I’d slyly stick gum on the back of my little brothers head. Our horse, Brussels, would nip it off, usually getting a bit of skin along with it. As we grow old, fat and bald, particularly bald, the sins of my youth give me cause to giggle.


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john6zx
Member (Idle past 4057 days)
Posts: 66
Joined: 01-27-2007


Message 219 of 327 (461976)
03-29-2008 1:25 AM
Reply to: Message 217 by Organicmachination
03-27-2008 10:45 PM


Re: Fabric of Space-Time
First of all, don't try and tell me to use a dictionary to define what I'm talking about. The definitions one will find in a dictionary are not scientific definitions. They are general ones defining general concepts known to laymen. When cosmologists talk about space-time, they don't mean what you think they mean. They don't mean the space between objects exactly. The "fabric" of space-time is a mathematical object, which, although not tangible, is seen in mathematical models of gravitation and quantum mechanics. You should look up these mathematical concepts yourself so that you can better understand them and know them before you try and argue against them.

What definition of space are these cosmologists using when they use this term space?

You say that the fabric of space-time is a mathematical object, which means that it is a concept and not an actual real physical object. So space and time are not physical. Look around you, use your experiences from life and tell me what perceptions of space or time make you think that they are real physical objects. Why do you think space and time are real physical things? Have you been told so, or have you perceived these things to be physical. Space and time are either real things or imagined (concepts). What scientific evidence can you show that proves beyond a reasonable doubt that space and time are real physical things?

Second, nothing is pulling the matter down the fabric of space-time. Matter and energy can only exist on the fabric itself, and so when it is curved by the mass of things like stars and galaxies, matter and energy have no choice but to follow that curve. Again, the fabric is a mathematical model that explains everything we see. Don't argue against it until you understand it.

Why would the matter follow a path down into the curve? The top of the warp is higher than the bottom. For matter to follow this path from one position and change course to follow another it must be acted upon by an outside force. Something has to motivate the mass from the top to the bottom.

Newtons first law of motion: Unless acted upon by an unbalanced force, a body at rest will remain at rest, and a body in motion will continue moving at the same speed and in the same straight line.

Again you say the fabric is a mathmatical model, which means it is a concept and not a real physical thing.

When you say that a mathmatical model explains all that we SEE, what you are saying is that a concept explains all physical objects and phenomenon.

That is akin to saying that the existance of God explains all that we see. You have to believe in God to agree with that kind of thinking,just as you have to believe that the model explains all that we see, because the model is just a mathmatical concept and is not an observable fact.

And "time" and "space" are not human made concepts, but are aspects of the natural world. They are as much human made concepts as diffusion is a human made law. Scientists seek only to explain these concepts by using models, the "fabric" of which I speak being one of those.

You say time and space are not man made concepts, so if they are not man made then they must be naturally occurring, right? You are telling me that time and space are just things that have always existed, existed like all the other things in this universe. Everything that exists, exists in some form of energy. So if these things existed on their own, before man, then some time in the past someone would have discovered one of these objects and gave it a name. You see man gives names to two types of things, those things that he perceives existing in the world around him and those things that exist in his head, (ideas, concepts, dreams, thoughts.) So time and space were given a name by man either because he came across these objects or by way of describing a concept. If time and space are real objects, like you say, then there would have been someone in the past who encountered one of these physical things and gave it a name. You see an object exists and then man gives it a name. So if time or space is an object who was the first to discover one of these objects? Where and when were these things discovered? If these things are physical they will occupy a location.

Diffusion is an occurrence that will happen whether it is a law or not. Man has observed this occurrence and codified it into law. Yes, the laws regarding the occurrence of diffusion are man made laws. The occurrence of diffusion did not come with a ready made tag with the laws on it.

You can put this debate to rest by showing scientific definitions of space and time that state that these things are naturally occurring or these things are real physical things. Just show me the definitions of time and space that these scientists are using when they talk of the warping of space-time.

My viewpoint on this topic is based on standard scientific definitions and observations of the world around me. I do not choose to believe this viewpoint, this viewpoint is based on established irrefutable facts and observations, not mathematical models or opinions from other people.

You have only made statements that are the standard answers to this topic given by those that believe that space and time are real physical things. I am asking you to define your terms, find out what the words time and space mean. Then tell me how these things could be real physical things.

You seem to be coming into this debate with as much knowledge of the concept as a city boy has knowledge of farming. You only know what you hear from other people and what you choose to believe. Before you come in here trying to debunk a standard explanation of gravity, try and understand what the explanation is saying instead of viewing it through warped and clouded eyes.

I think this quote was meant for you.


This message is a reply to:
 Message 217 by Organicmachination, posted 03-27-2008 10:45 PM Organicmachination has replied

Replies to this message:
 Message 221 by Organicmachination, posted 03-29-2008 2:40 AM john6zx has replied

  
john6zx
Member (Idle past 4057 days)
Posts: 66
Joined: 01-27-2007


Message 220 of 327 (461978)
03-29-2008 1:50 AM
Reply to: Message 218 by lyx2no
03-28-2008 1:36 AM


Science doesn't try to make the idea of space more that it is; it tries to define it.

Science already has a definition for space. Check your scientific dictionary.

There are those in the scientific community that are still trying to find out what space is made of. Yet there own technical dictionaries tell them that space is not a physical thing.

Space is physical.

According to what scientific reference?

If space were physical it would have to exist in a location just like the rest of the physical things that exist in this universe do. Something that is physical is not space, it exists in a location we call space. For space to be physical it would have to occupy a location, this is fundamental observation in physics.

And while we're at it, you might want to try learning physics from a physics book rather than a dictionary.

I learn physics from the standard books issued to students who are enrolled in a physics courses. When I want to get a better definition of a term or get a better understanding of a term I use a standard dictionary.

Dictionaries are an essential tool in learning any subject. Let me ask you, where did you get your definition of space from?


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Organicmachination
Member (Idle past 4946 days)
Posts: 105
From: Pullman, WA, USA
Joined: 12-30-2007


Message 221 of 327 (461980)
03-29-2008 2:40 AM
Reply to: Message 219 by john6zx
03-29-2008 1:25 AM


Re: Fabric of Space-Time
What definition of space are these cosmologists using when they use this term space?

You say that the fabric of space-time is a mathematical object, which means that it is a concept and not an actual real physical object. So space and time are not physical. Look around you, use your experiences from life and tell me what perceptions of space or time make you think that they are real physical objects. Why do you think space and time are real physical things? Have you been told so, or have you perceived these things to be physical. Space and time are either real things or imagined (concepts). What scientific evidence can you show that proves beyond a reasonable doubt that space and time are real physical things?

So you're effectively arguing that because space and time are not tangible, physical objects, that they cannot be used to describe natural phenomena? What are your emotions then? What are your feelings? What are your memories? What are your sensations? A thing need not be tangible to exist and affect things around it. Space is simply that, the medium in which matter exists, and time, although still a question among scientists and philosophers, is generally agreed on as the passage of events. One can describe space and time being linked because mathematically, they are. Just as the magnetic and electric fields in an EM wave are linked, so are space and time. Without space, there is no time, and without time, there is no frame of reference from which to deduce space. Just because space and time are not physical, it does not mean that they do not exist or cannot be a part of our universe.

Why would the matter follow a path down into the curve? The top of the warp is higher than the bottom. For matter to follow this path from one position and change course to follow another it must be acted upon by an outside force. Something has to motivate the mass from the top to the bottom.

Newtons first law of motion: Unless acted upon by an unbalanced force, a body at rest will remain at rest, and a body in motion will continue moving at the same speed and in the same straight line.

Newtonian physics are valid only within our physical universe. When the fabric of space-time is curved, our actual physical universe is curved, and Newton's laws work within that curvature. Newton's laws will not force an object to continue along a straight path unless that path is part of our universe, within which our physics make sense. Therefore, an object traveling along space-time will not require energy to follow a bend in it, because the bend is the only part of the universe that the object can travel upon.

When you say that a mathmatical model explains all that we SEE, what you are saying is that a concept explains all physical objects and phenomenon.

No. When I say that a model explains what we see, you know as well as I do that what I mean is that a model explains the observable phenomena for which that model is created. The model of space-time explains the laws of physics and why they hold in our universe, and how Gravity works. However, our knowledge of Gravity is not complete, and there might need to be made some changes in our model to account for new information. You however, seem to have no idea what in the hell the model actually states, and yet are insistent on debunking it.

You say time and space are not man made concepts, so if they are not man made then they must be naturally occurring, right? You are telling me that time and space are just things that have always existed, existed like all the other things in this universe. Everything that exists, exists in some form of energy. So if these things existed on their own, before man, then some time in the past someone would have discovered one of these objects and gave it a name. You see man gives names to two types of things, those things that he perceives existing in the world around him and those things that exist in his head, (ideas, concepts, dreams, thoughts.) So time and space were given a name by man either because he came across these objects or by way of describing a concept. If time and space are real objects, like you say, then there would have been someone in the past who encountered one of these physical things and gave it a name. You see an object exists and then man gives it a name. So if time or space is an object who was the first to discover one of these objects? Where and when were these things discovered? If these things are physical they will occupy a location.

Jeezus Christ. You seem to have no idea what you're talking about. Time and space have existed since the Big Bang, and perhaps before. Just because we came up with terms for them later does not mean that they came into existence the moment we thought up what to call them. Surely, you can see what a ridiculous position you are implying. I never said that time and space are real objects, only that they exist and that our current theories about space-time and the 4 fundamental forces of the universe predict and explain their existence. What are you getting on about? You seem to think that I believe that time and space are objects like a ball and some wooden cube that one can just pick up and play around with. Where in the hell did your reasoning go so wrong that you've come to think this? Again, I will emphasize that you understand this topic before you try and argue against it. As it stands, none of your questions have been insightful, rooted in any modern cosmological theory, or even made sense. You seem to be coming at the topic of cosmology from a philosopher's point of view without realizing that it is philosophy, not time or space that is a man made concept.

You have only made statements that are the standard answers to this topic given by those that believe that space and time are real physical things. I am asking you to define your terms, find out what the words time and space mean. Then tell me how these things could be real physical things.

Unless you want to take a 400 level cosmology course at a university, you will never understand what scientists are talking about, because, frankly, it seems that the mathematics are far above your head. And also frankly, I don't have the patience to sit here and teach you what the past 200 years of scientific theory has taught the world. In fact, the burden to educate lies upon your own shoulders, not mine, and you need to do some serious research into cosmology and quantum and field mechanics before you can have a hope of making any sort of logical arguments against this concept. The audacity and the sheer arrogance you show by trying to prove to me and others on this website that cosmology is fundamentally flawed when you don't even understand the basics is apalling, and before you start considering yourself a wise or learned person, try and ask yourself what the hell it is exactly that you think you know.

I think this quote was meant for you.

This just made me laugh, and die a little inside. The only thing worse that your complete lack of knowledge in the science behind cosmology is your apparent and arrogant belief that you do, in fact, know what you're talking about.


This message is a reply to:
 Message 219 by john6zx, posted 03-29-2008 1:25 AM john6zx has replied

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cavediver
Member (Idle past 2879 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 222 of 327 (462010)
03-29-2008 10:47 AM
Reply to: Message 174 by Silent H
03-09-2008 5:47 PM


Re: the gravity of general relativity
Ok, very belated reply...

Would I be wrong in taking this as a suggestion of "math is the language of God" or more secularly "math is the language of the Universe"?

I'd possibly swing it around and say the Universe is simply how our perception sees the mathematics. It always sounds like a copout, but you really do need to get down and dirty with the fundementals to get so strong an impression. I've gained an appreciation for this view from the evidence; there was no a-priori desire for this to be the case. Even trying to provide simple examples of this is diffciult, but I guess one would be: consider distance - distance is merely a field that gives values assigned to pairs of points. So the distance say the Andromeda galaxy is away from you compared with your keyboard, is merely a case of a difference in a couple of values. There's no 'real' sense that Andromeda is way off in the Universe and the keyboard is next to you. As Morpheus so perceptively pointed out 'is that really air you are breathing?' - but this is far beyond GR and definitely for another thread if you want to explore this further.

Okay, I think I get this idea. Let me repeat to make sure. Energy can be diffuse, or compact. When compacted in a location it exhibits the properties we ascribe to mass. If that compaction is of a self-sustaining nature it is what we'd call a particle with mass?

Yes, except that even when energy is 'diffuse' it still has an associated mass.

Take my classic space-time picture of a closed FRW universe - the globe. T=0 is the North Pole, with time flowing south. Care to suggest where the time directions of two separated particles would be parallel?

If I understand your description my guess would be the south pole (parallel but opposite direction)?

Nice :) and I dodn't think of that! I was thinking of the equator, where they will all be pointing the same way. But north of the equator, they will all be directed somewhat away from each other, as they follow the lines of longitude, and once past the equator, they will all be directed somewhat towards each other.

As a follow on to that, why does mass create a situation where a fully time directed vector sets two masses in physical motion towards each other.

The masses in isolation experience no accelerations and simply trace out their path through time, following their purely time directed vectors. But near each other, their vectors are tipped by the space-time curvature generated by each other. To a distant observer, he sees the masses accelerate towards each other, and either collide, slingshot, or enter into orbit, but there are no 'forces' acting upon either mass. It is just that their own time-directions are being twisted by the other mass.

I guess this is to ask, why does my natural path through time always point toward the center of something else?

It doesn't - in orbit, your path winds around the centre. But either way, that is just how space-time warps in the presence of the mass.

And why am I increasingly moving toward that center, rather than uniformly moving (I'd assume that's due to the nature of a curve rather than a straight line)?

That's a good question - Back to the rubber sheet analogy, the gravitational mass creates a smooth depression, where the curvature increases as you get closer to the centre, so the time vector tips over more as you approach the centre - hence you appear to accelerate. If the depression was sharply conical, with a discontinuity where it joins flat space, you would instantly jump from zero inward velocity to some finite velocity (with momentary infinite g!!) and that inward velocity would remain constant as you fell inwards. Fortunately, space-time responds rather more smoothly to the presence of mass, which in turn gives rise to the whole of Newtonian gravitation and F=GMm/R^2 in the weak gravitational limit...


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 Message 174 by Silent H, posted 03-09-2008 5:47 PM Silent H has replied

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 Message 227 by Silent H, posted 03-29-2008 7:41 PM cavediver has replied

  
cavediver
Member (Idle past 2879 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 223 of 327 (462012)
03-29-2008 11:19 AM
Reply to: Message 214 by Fabric
03-27-2008 5:43 PM


What is a derived property ?

For example space is not energy because energy is a derived property, but as stated i dont understand what it means.

As I've mentioned before: at our present level of understanding, existence is a multi-layered fabric or sheet. We call these layers, fields. One special layer dictates the overall shape of the fabric, and you can imagine the other layers conforming to this shape. This special layer also gives rise to what we think of as disatnce. Ripples and bumps in the other layers give rise to what we call photons, electrons, quarks, electromagnetic fields, etc. You yourself are a simply a particular arrangement of bumps accross these fields! As is the planet you are standing on.

What we call energy is essentially a measure of how bumpy the layers are in a particular region. Conservation of energy is simply the observation that bumpiness is conserved - i.e. if you have a certain bumpiness in a small region of the fabric, that bumpiness can be redistributed between the different layers, it can be reduced by pushing it outside that small region, it cn be increased by augmenting it from outside that region, BUT it cannot be made to "vanish" and it cannot be made to "appear". Simple, huh?


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cavediver
Member (Idle past 2879 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 224 of 327 (462017)
03-29-2008 12:24 PM
Reply to: Message 220 by john6zx
03-29-2008 1:50 AM


I learn physics from the standard books issued to students who are enrolled in a physics courses. When I want to get a better definition of a term or get a better understanding of a term I use a standard dictionary.

:eek: and have you ever actually passed a physics course? What the hell has a "standard dictionary" to do with learning physics? Your lack of knowledge exhibited here is painful evidence of the futility of trying to learn physics this way. Even specific science/physics dictionaries are only really useful up to first year undergrad level.

And space-time is most certainly phsyical, and along with the quantum fields, just about makes up the totality of existence as far as we are yet aware.

If space were physical it would have to exist in a location just like the rest of the physical things that exist in this universe do. Something that is physical is not space, it exists in a location we call space. For space to be physical it would have to occupy a location, this is fundamental observation in physics.

Hmmm, if you say so...


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lyx2no
Member (Idle past 3952 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


Message 225 of 327 (462023)
03-29-2008 1:30 PM
Reply to: Message 224 by cavediver
03-29-2008 12:24 PM


Thank-you cavediver
You just saved me a suspension.


Kindly

∞∞∞∞

When I was a child I’d slyly stick gum on the back of my little brothers head. Our horse, Brussels, would nip it off, usually getting a bit of skin along with it. As we grow old, fat and bald, particularly bald, the sins of my youth give me cause to giggle.


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