What is the Fabric of Spacetime Made Of?

[john 8]

Hi john 8, it has certainly been a while, welcome back. Sorry about being imprecise, by "flatten the time dimension" I meant "take a projection along the time dimension". Specifically, a 3D projection of the 4D worldline of the satellite.

Hi DaleSpam.

I remember you from the thread regarding "Is time a dimension". We got into a discussion about if time was a real physical thing or not. I stated that time was not a real physical thing, you disagreed with me. We never resolved that issue, although I would like to.

Anyway, let's start off with a perfect understanding of each others ideas regarding this topic. I hope that you can agree that the only true way to understanding in communication is make sure that the people involved in the communication are familiar with and are using the same definitions of terms used in the communication.

In your above quote what exactly are you talking about? Are you talking about a physical action taking place or a concept in a math model? From the definitions of the terms that you are using it sounds like you are talking about a math model, something that only exists on paper or as a concept. Do I have this right?

 

[john 8]

Original quote by john 8 that is being referred to:

“So are you saying that space-time is an actual physical thing? Yes/no.

If yes, please give a scientific reference that describes the physical structure of space-time. Remember that all things that we deem to be real physical things are made of energy. This energy either takes the form of a particle or a wave. if you know of a different way in which things exist please let me know. Otherwise, tell me and the rest of us participating on this discussion what form space-time exists as.”

Wow. You have said my words exactly, if I could have ever thought of a good way to say my own questions about this. I love Relativity so much, but sometimes when I try to imagine it, the words people say about it just don't help me see it in my mind. I just can not imagine a thing that is not matter or energy that can be put into a curve or be flat or be anything, because it is nothing! It is not there! If nothing is there then there is no thing that can be curved!

Thanks for saying my question that I did not know how to say!

You are welcome, glad I could help.

 

[Dale]

In your above quote what exactly are you talking about? Are you talking about a physical action taking place or a concept in a math model? From the definitions of the terms that you are using it sounds like you are talking about a math model, something that only exists on paper or as a concept. Do I have this right?

A projection is an operation that you can perform in order to reduce the dimensionality of a higher-dimensional data set. It is usually used for visualization purposes. For example, a 3D rendering is a mathematical projection of a 3D scene onto a 2D image. An X-ray image is a physical projection from 3D onto 2D.

The projection I was talking about above was purely for visualization purposes and is neither something physical nor something that is part of the math of GR.

 

[A.T.]

So are you saying that space-time is an actual physical thing? Yes/no.

Remember that all things that we deem to be real physical things are made of energy. This energy either takes the form of a particle or a wave.

By this definition neither space-time, nor forces, nor EM-fields are physical things. They all are just useful concepts used in physics. Just like energy, particles and waves, which you use to define what "real physical things" are.

 

[Dale]

On that same note, john 8, I would still like to hear your time-free definition of energy or waves. If only matter and energy or particles and waves are "physical" according to you and time is not "physical", then you should be able to define energy and waves without any reference to time. Otherwise time is required for energy and waves and therefore every bit as "physical" as energy and waves.

 

[john 8]

Originally Posted by john 8

:So are you saying that space-time is an actual physical thing? Yes/no.

Remember that all things that we deem to be real physical things are made of energy. This energy either takes the form of a particle or a wave.”

By this definition neither space-time, nor forces, nor EM-fields are physical things. They all are just useful concepts used in physics. Just like energy, particles and waves, which you use to define what "real physical things" are.

These are not my definitions. They are standard scientific definitions.

By this definition force, EM fields, particles, waves, are physical things. Look up the definitions of physical, things, force, EM fields, energy, particles. Force or energy is the work done by a particle or wave, or the potential of work by a particle or wave.


Everything that exists in this universe that can be sensed, measured, or perceived is either made of a particle or a wave. There are no exceptions. These things that are made of particles or waves are classified as physical things, these things make up the physical universe.

Look, don’t just take my word for it. Learn, read, study, find out for yourself. After you have gotten some certainty on this, ask yourself are space, time, space-time physical things made of particles or waves.

If not then maybe they are just concepts.

This question goes out to all of you, is space-time a physical thing?

I am sure someone who thinks space-time is a physical thing can give an explanation or show a reference.

 

[Naty1]

at the largest scale the universe is flat to within 1 in 447,225,917,218,507,401,284,016?
If so, what would that mean?

According to theoretical physics, space thought to be EITHER flat or positively curved or negatively curved...experiments so far suggest it's flat...

 

[john 8]

On that same note, john 8, I would still like to hear your time-free definition of energy or waves. If only matter and energy or particles and waves are "physical" according to you and time is not "physical", then you should be able to define energy and waves without any reference to time. Otherwise time is required for energy and waves and therefore every bit as "physical" as energy and waves.

Right, time is not a physical thing. If you think that it is show me the reference. Currently there is no definition of time that defines it as a physical thing.

Time is not a physical thing due to lack of evidence to support a claim that it is a physical thing.

Science does not claim that time is a physical thing. There is nothing to support a claim that time is a physical thing. This is true.

If you want to say time is a physical thing than just show some evidence of this. Really, just put this to rest and show me that I am wrong.



Time either exists as a physical thing or it does not. If it is a physical thing then why doesn’t science recognize this. Find your evidence, a definition, observation, something. The fact that no one has provided any evidence that time is a physical thing just goes to strengthen my assertion that time is not a physical thing.

. If only matter and energy or particles and waves are "physical" according to you .

Not according to me, according to science. Do you even have an understanding of basic science?

I am not making up definitions. If you have a problem or disagreement with the definitions that I am using then you have a problem with the established empirical facts that are the basic building blocks of science.

You seem to want to deny what science has established as what is a physical thing and what is not.

Time is not a physical thing if you think that it is then you are in error and are in disagreement with science.

I am on the side of science.

Maybe you are having a problem accepting the fact that time is not a physical thing because you believe that SR and GR are explanations of the real physical workings of the universe and want to continue to prop up the belief that there is real phenomenon of time dilation, a big structure out in space that all of the planets are currently rolling around on. Is this what you believe. There is a big flat something in space that is just floating out there with planets rolling around on it? Maybe we are on the back of a big giant turtle. Maybe a big man named Atlas is holding us up.

The whole idea of a space-time fabric is not grounded in scientific reality. In order for SR and GR to be descriptions of real physical occurrences, time and space have to be real physical things that can interact with other physical things. If these things, time and space are real physical things then why hasn’t science stated this fact?

Sooner or later you are going to have to accept the fact that space and time are not physical things. There is no evidence that has ever existed to prove otherwise.

If you think time is a real physical thing then just show proof. Why do I have to keep asking this? Is it so difficult to do. Just participate in this discussion and support your claim with science and evidence.

 

[A.T.]

Force or energy is the work done by a particle or wave, or the potential of work by a particle or wave.

You need to learn the difference between force and energy.

Everything that exists in this universe that can be sensed, measured, or perceived is either made of a particle or a wave. There are no exceptions.

But space and time can be measured, yet they are neither particle nor wave.

I am on the side of science.

Who cares? Science is neither particle nor wave, so it is not a "real physical thing".

 

[Naty1]

John 8 posted...

I am sure someone who thinks space-time is a physical thing can give an explanation or show a reference.

Why limit your inquiry to space and time??

Is mass a physical thing? Is energy? Gravity?? Prove it! Nobody can...and how about dark mass and dark energy? Are they "a physical thing"...is 94% of the universe a "physical" thing that we have barely an understanding of at a basic level...seems that way...

Of course we take all those for granted, but nobody knows exactly...Keep in mind everybody assumed time and space were constant and unchanging until Einstein showed otherwise...so what we "know and understand" today is severely limited by our meager senses and limited evolutionary requirements for survival.

Nor do we know that exact constituents of space nor time...but that doesn't mean they are not physical...I posted similar thoughts very early in this thread... nobody can prove nor disprove physicality at this point...but we can begin to describe it in many ways...strings,branes, Penrose spin networks,spinfoam and on and on...so we have a start at understanding...

Mass, gravity, energy and space-time all appear to have emerged from an initally very unstable high energy environment where all were combined (unified) into one entity...those unstable initial conditions apparently resulted in the big bang, inflation and a lower energy more stable universe we inhabit...we have evidence, but not conclusive proof..for example certain forces can be unified: strong,weak, electromagnetic...but not so far gravity...so there is a belief that eventually we can unify all the forces under one mathematical construct...eventually that might include mass,time,etc...

 

[Naty1]

Time is not a physical thing due to lack of evidence to support a claim that it is a physical thing.

Where did you EVER get that thought??

You can't be reading on this forum and really believe THAT!

 

[john 8]

According to theoretical physics, space thought to be EITHER flat or positively curved or negatively curved...experiments so far suggest it's flat...

If space is flat then what is it existing in? What is outside the surface of this flat thing. This flat thing is made of what? The space between you and the computer monitor is that flat? There is the idea of space all around us what is flat about that.

This flat thing, is it above the Earth, below the Earth? Is the Earth in contact with it? If not then is there a distance between the Earth and this flat thing? If so what would you call the area that is between this flat thing and the Earth.

Do you see how absurd it is to believe that there is a flat thing called space .


Look, I am not trying to pick on you, but where has all the science and logic gone in this thread? The things that are being stated here are just silly. It is like being at some sort of science fantasy camp where the only requirement is to throw all logic and science out the window and just have fun with make believe.

Does anyone have the ability to think and not just repeat what they have been told? Think about what you are saying.

 

[john 8]

Originally posted by john 8

“Time is not a physical thing due to lack of evidence to support a claim that it is a physical thing.”

Where did you EVER get that thought??

You can't be reading on this forum and really believe THAT!

It is not a thought or belief. It is a statement of fact. There is no evidence to support the claim that time is a physical thing.

If you disagree, just show me a definition, or observation, or experiment that describes the physical structure of time.

All things that are considered to be physical are either made of a particle or a wave. This is according to science, not me.

If you think time is a physical thing then just provide some scientific evidence of this evidence of this.

 

[Dale]

I am not making up definitions.

Yes, you are. I have never heard anyone but you ever assert that all physical things are either particles or waves. It is entirely a definition made up by you. However, I have no problem with that definition. I just think that time and space are implied in the definition of a wave and therefore also "physical" by that definition.

So again, I ask how do you define a wave (or energy) without time? If you cannot then how can you assert that time is not "physical" according to your own definition of the term?

Re: http://www.edu-observatory.org/physics-faq/Relativity/SR/experiments.html" that time is physical (of or pertaining to physics, not your "wave or particle" definition).

 

[john 8]

Yes, you are. I have never heard anyone but you ever assert that all physical things are either particles or waves. It is entirely a definition made up by you. However, I have no problem with that definition. I just think that time and space are implied in the definition of a wave and therefore also "physical" by that definition?).

All physical things are either a particle or a wave, that is what science says not me. Look for yourself, are you so unfamiliar with the basics of science? You are going to have to stop saying that I am making up definitions, it is an incorrect statement.

So again, I ask how do you define a wave (or energy) without time? If you cannot then how can you assert that time is not "physical" according to your own definition of the terms.?).

Again not my definitions.

So again, I ask how do you define a wave (or energy) without time? If you cannot then how can you assert that time is not "physical" according to your own definition of the term?).

This is a question. Not an definitive answer to the nature of time. You have used the term time in your question. What definition of the term time are you using? Is it "Of or pertaining to physics"? If so read your question using that definition and see if it makes sense or is what you are trying to communicate.

Re: http://www.edu-observatory.org/physics-faq/Relativity/SR/experiments.html" that time is physical (of or pertaining to physics, not your "wave or particle" definition).

Again with this pertaining to physics. I am not asking that. We can all agree that the subject of time is used in physics. I am asking if time is a physical thing, something that is made of a particle or a wave.

If you do not think that time is made of either a particle or a wave then just say so, but you cannot then go on to say that time is something that dilates, or slows down, or was made at the Big Bang, or is a thing that has some type of existence. Time either exists or it doesn’t. if it exist as a physical thing then science would define it as such and time would have the qualities of all those other things that are considered to be physical.

In the link that you provided, did you find evidence of time being a physical thing? I have been referred to this link before and there is no evidence that time is a physical thing. If the link you provided has this evidence why don’t you just copy and paste this evidence and post it.

Here you are looking for evidence that time is a physical thing, but I notice that you did not send a definition of time to prove your point. Would not that be the quickest and easiest way to prove your point.

What! You did not find any scientific reference or definition to support your claim. How weird, yet you continue to assert that time is a physical thing. Why is that? Are we all just free to make up stuff and never have to back it up with facts. Is that what this form is all about?



Why is it that I seem to be the only one who notices that no one has provided any scientific evidence to back up their claims that time is a physical thing?

Still no evidence. How much longer can this go on until it is realized that time is not a physical thing?

 

[Dale]

Again with this pertaining to physics. I am not asking that. We can all agree that the subject of time is used in physics. I am asking if time is a physical thing, something that is made of a particle or a wave.

I think we are in agreement then. We both agree that time is used in physics and we both agree that time is not made of a particle or a wave.

This is a question. Not an definitive answer to the nature of time.

Yes, a question which you also avoided answering last time I asked it. I answered your question, so now you have no excuse to not answer mine.

The usual definition of a wave is:
$${ \partial^2 u \over \partial t^2 } = c^2 \nabla^2 u$$
As you can see, time is part of this definition. So is this the definition of "wave" that you are using or not? If not, what is your definition of wave and is time part of it?

 

[p764rds]

Originally posted by john 8

“Time is not a physical thing due to lack of evidence to support a claim that it is a physical thing.”

I have just read this thread and am trying to show that 3D physical space is illogical.
A school teacher told me (I never forgot what he said) that the theories of space assume that it exists in the first place (and then go on to bend, shape it). He was annoyed and told that he thought this assumption (of space existing in the first place) to be fudged to fit 'the facts'!
I want to suggest its an unjustified assumption that real physical space is possible (and then offer another theory of 3d space - informational). Its empty - how can it hold up at all? Manifold or not.

I am trying to show that this space-time theory lies on shaky foundations (and that what we really see around us - is in information where 3D space is very, very easy to make).

Manifolds, bending by gravity - fine - no problems. Relativity, Lorentz invariance- no problems. But is it an initial assuption that it exists in the first place unproved?

 

[Dale]

There is no requirement that a physical theory start from no assumptions. Making such assumptions leads to theories that are consistent with observation. So I really don't see the value in what you are attempting.

 

[A.T.]

Manifolds, bending by gravity - fine - no problems. Relativity, Lorentz invariance- no problems. But is it an initial assuption that it exists in the first place unproved?

You cannot prove that anything exists. Do numbers really exist? They are just an abstract idea, quite useful though, aren't they? Space-time is no different.

 

[ThomasT]

... just show me a definition, or observation, or experiment that describes the physical structure of time.

Time refers to the configuration, or arrangement, or relative position of a set of physical objects.
So, time, in the most general sense, is any and all physical structure(s).

We 'keep time' or 'track time' or make 'time indexes' of a set of objects whose configuration is changing by associating the set of objects with the changing configurations of some other set of objects such as a conventional clock.

I want to suggest its an unjustified assumption that real physical space is possible.

Imho it's a justified assumption. There's lots of experimental evidence to suggest that there's activity in even the emptiest of empty spaces inside our universe, to vanishingly detectable energy scales.
For example, the observed effect on accelerated oscillators predicted by SR and GR.

The structure of the 'fabric of spacetime' is of course unknown. The fundamental medium of our universe might be effectively undectable, ie., nonphysical as far as we might be able to determine (even if it's particulate, but especially if it's nonparticulate). But it can still be used as a metaphysical framework from which a conceptually and mathematically unified theory of the physical (detectable by us) universe might be developed.

From the observational evidence and success of certain theoretical constructions it might be inferred that physical reality is fundamentally wavelike. Particulate structures, ie., more or less bounded, standing wave structures, and a hierarchy of particulate media might be formed via countless iterations of some (or a) fundamental wave dynamic(s) -- with the wave behavior in the particulate media being fundamentally governed by the same wave dynamics which produced the particles that define the media. It would also seem likely that higher order, scale dependent organizing principles would emerge as media interface and merge and wave interaction becomes increasingly complex.

GR's depiction of gravitational behavior is a mathematical simplification of increasingly intense and complex wave interaction. And, of course, a rather good and useful theory. However, the posts in this thread are evidence of how difficult it is to make a 'picture' of reality from a mathematical model that's, necessarily, somewhat removed from that reality. (The exchange particle 'picture' of gravity would be a step closer to the wave mechanical reality).

If this makes little sense, then I apologize. And I also apologize for the parts of this post that are out of place in this forum, but it seemed ok for this particular thread. Anyway, I do think of space and time as aspects of physical reality -- with space being the 'stuff' and time being how the 'stuff' is configured. And the posts have been interesting and fun to read.

 

[Naty1]

John8...Try reading Kip Thorn' s "Black Holes and Time Warps"...you'll be able to get a sense for the physicality of space in Thorne's discussion of black holes...his explanations of how space interacts in various ways makes it unmistakably clear space IS something...it IS a physical entity...but of course no one knows exactly what, any more than anyone knows exactly what matter,time,or energy might be...

 

[p764rds]

You cannot prove that anything exists. Do numbers really exist? They are just an abstract idea, quite useful though, aren't they? Space-time is no different.

hmmmm interesting that 'you cannot prove space exists'. Also John8 seems to think like I think on this matter.

Lets take a simple scenario. Assume we have nothingness (i.e. what is 'outside' the Universe' - no space-time) and let's make an empty spherical space of radius 1 billion miles in the nothingness (OK, a flat euclidean space if you like - no gravity).

This 'space' is actually a mathematical statement (a sphere of radius r) and cannot physically exist. Isn't it logically absurd to have such a scenario, even in thought it does not work - because its mathematics not physicality. I am trying to suggest that physical 3d space is impossible to have and its actually in information where its easily produced and shaped.
So what have we got in our Universe that we think is x,y,z physical space? IMO its in information -information does not require physical space to exist, its also massless, and creates an illusion of 3D space very easily because it can implement mathematics.

Isn't it impossible to have an empty space located in nothingness - because its mathematics and not physical? All the space-time mathematics IMO start out with x,y,z (squared etc) without justifying the right to do that.


note: I am activley looking evidence in this direction - so all references and 'higher truths' gratefully received.

 

[FredericGos]

Are all these word manipulations back & forth not just mental masturbation? Juggling with undefined terms & self referring abstractions. Does an illusion exist?

Sorry for the harsh words, but at this level, I think that the only arguments pro or con should come from mathematics. So if you want to prove wether or not spacetime exists (whatever that means), you have to do it mathematically.

Human language is not going to cut it, and this thread will go on forever without any progress. Just a lot of ping pong.

I'd rather ask another question. Is spacetime emergent or not? But then again, if you twist your mind long enough, maybe THAT's the definition of exists? In mathematics that is.

Anyway, I'm writing this because I get tired of reading people claiming to be able to prove this and that all the time. As far as I know, the only place you can prove anything is in math. No math, no proof.

/Frederic

 

[john 8]

I think we are in agreement then. We both agree that time is used in physics and we both agree that time is not made of a particle or a wave.

Yes, a question which you also avoided answering last time I asked it. I answered your question, so now you have no excuse to not answer mine.

The usual definition of a wave is: $${ \partial^2 u \over \partial t^2 } = c^2 \nabla^2 u$$
As you can see, time is part of this definition. So is this the definition of "wave" that you are using or not? If not, what is your definition of wave and is time part of it?

Lets see here, you say time is not a wave. then you go to give a definition of a wave and say that time is part of this definition of a wave. O.K. Pause; I want to give you time to think about what you said.

Go ahead, I will allow you to really think about what you just said.

Maybe you should have a cup of coffee and go for a walk, clear your head.

You have now asked me to give my definition of a wave. You have totally changed the topic.

You sound a bit confused. You say that time is not a wave and then say that time is part of the definition of wave. Really, read what you wrote to me.

So, is this your evidence that time is a physical thing? If so, are you now saying time is a wave?

Come on, this must be a joke, right?

Well, why don't you make up your mind and get back to me.

I still say that time is not a real thing, and no one has proven me otherwise.

Can someone come up with some scientific evidence that time is a real physical thing?

There is the whole internet to find your answer.

 

[JesseM]

john 8, are you ever going to address the time/distance analogy from post 148 on this thread and various previous posts I linked to there? For example, distance is part of the normal definition of a wave since there must be some distance between crests to define the "wavelength", but would you say therefore that "distance is a wave"? I don't think these two statements are equivalent, myself. Do you think that distance is a "real physical thing"?

 

[john 8]

I have just read this thread and am trying to show that 3D physical space is illogical.
A school teacher told me (I never forgot what he said) that the theories of space assume that it exists in the first place (and then go on to bend, shape it). He was annoyed and told that he thought this assumption (of space existing in the first place) to be fudged to fit 'the facts'!
I want to suggest its an unjustified assumption that real physical space is possible (and then offer another theory of 3d space - informational). Its empty - how can it hold up at all? Manifold or not.

I am trying to show that this space-time theory lies on shaky foundations (and that what we really see around us - is in information where 3D space is very, very easy to make).

Manifolds, bending by gravity - fine - no problems. Relativity, Lorentz invariance- no problems. But is it an initial assuption that it exists in the first place unproved?

Now you are on the right track. Physics is the branch of science concerned with the laws that govern the structure of the universe, and the investigation of the properties of matter and energy and their interactions. Not some religion based on faith and assumptions.

Without energy no action is possible. If you say time dilates, then show the energy. You say time is part of a supernatural fabric that controls the motion of planets, then show the energy.

It takes work to change the direction of a planet, work is energy, if time and space are changing the direction of planets then those thing have to be some form of energy. Get back to basics, and stop with this religious belief in things that rely on faith, belief, or a total disregard for established scientific laws.

Here is a simple way to end this. You think time is a real thing then using science and the terms defined in science, give evidence of your thinking.

Look over this thread since I asked someone to provide evidence that time is a real thing and you will see that no one has given any evidence, and all that has been done is protests about semantics. I am telling you right now, I mean every word that I say, all of the words that I use can be found in a standard dictionary, and apply to the context of my statement.

Time is not a physical thing! No confusion about what I said.

If I was to say that a rock was not a real physical thing, I would get proof that it was, and no one would argue this crap about semantics. You know what I am talking about, you just do not have any evidence, so you are stalling and misdirecting.

You think time is a physical thing, then use science to do your talking. Prove me wrong.

How many times do I have to say this?

 

[john 8]

Time refers to the configuration, or arrangement, or relative position of a set of physical objects.
So, time, in the most general sense, is any and all physical structure(s)..

From what you just said time is both a particle and a wave. Rocks, light, birds, water, air, all physical strutures. Look. this thread needs to be more specific, not vague, ambiguious answers.

Just for the record, you are saying time is a physical structure.

We 'keep time' or 'track time' or make 'time indexes' of a set of objects whose configuration is changing by associating the set of objects with the changing configurations of some other set of objects such as a conventional clock.)..

Just for the record, This is an explanation of a clock and time keeping. Thank you.

The structure of the 'fabric of spacetime' is of course unknown. .)..

Really? Nobody knows? All this talk of this supernatural sky fabric,and nobody really has any idea of what they are talking about. Just to be fair, let's say that it is unknown to you.

Now according to physics, if work is being done then energy is involved. This fabric is changing the direction of the planets, so work is being done by this floating fabric. So this fabric of God has to be made of some form of energy. That is the law of physics, it is the law of nature, and there are no exceptions. Period.

This fabric does not exist. It is a fantasy. I am sure that some of you find this heresy, and want to burn me at the stake for not following your beliefs, but I love and respect science too much to corrupt it with fantasy.

Go ahead and use science to prove me wrong.

The fundamental medium of our universe might be effectively undectable, ie., nonphysical as far as we might be able to determine (even if it's particulate, but especially if it's nonparticulate). But it can still be used as a metaphysical framework from which a conceptually and mathematically unified theory of the physical (detectable by us) universe might be developed..)..

Might be? Wow that is a definative answer! Look, why is this so hard for some of you? Physics is not based on maybe, or might be. All of your questions about physics are answered by physics.

As for the rest of what you said here, that is a lot of talk about nothing. What did you say exactly.

From the observational evidence and success of certain theoretical constructions it might be inferred that physical reality is fundamentally wavelike. Particulate structures, ie., more or less bounded, standing wave structures, and a hierarchy of particulate media might be formed via countless iterations of some (or a) fundamental wave dynamic(s) -- with the wave behavior in the particulate media being fundamentally governed by the same wave dynamics which produced the particles that define the media. It would also seem likely that higher order, scale dependent organizing principles would emerge as media interface and merge and wave interaction becomes increasingly complex..

O.K. So what did you say here? Take a stand and use conviction, sounds like you are unsure, if you are unsure in your explanations how will that help anyone else gain certainty?

GR's depiction of gravitational behavior is a mathematical simplification of increasingly intense and complex wave interaction. And, of course, a rather good and useful theory. However, the posts in this thread are evidence of how difficult it is to make a 'picture' of reality from a mathematical model that's, necessarily, somewhat removed from that reality. (The exchange particle 'picture' of gravity would be a step closer to the wave mechanical reality)...

O.K. Thank you for that.

If this makes little sense, then I apologize. And I also apologize for the parts of this post that are out of place in this forum, but it seemed ok for this particular thread. Anyway, I do think of space and time as aspects of physical reality -- with space being the 'stuff' and time being how the 'stuff' is configured. And the posts have been interesting and fun to read.

You said what you think, thank you. Now what does science say of space and time. That is what I am looking for from someone, not personal opinions or thoughts.

Thank you.

 

[john 8]

John8...Try reading Kip Thorn' s "Black Holes and Time Warps"...you'll be able to get a sense for the physicality of space in Thorne's discussion of black holes...his explanations of how space interacts in various ways makes it unmistakably clear space IS something...it IS a physical entity...but of course no one knows exactly what, any more than anyone knows exactly what matter,time,or energy might be...

Stop with this run around. Is a rock a physical thing according to science? Yes/No

Is light a physical thing according to science?

Science has defined itself and it's definitions.

I know many of you will take offense to this next thing I say but;

Are some of you on this thread just kids unfamiliar with physics and you are just here having fun?

I can not understand how some of you can say the things that you do if you had any basic understanding of science.

What you said is hogwash. Science has defined what is real. This talk of philosophy is just an avoidance of my initial question. Look up the term real in a dictionary, that is what I mean by real. The term real is defined. We all know what real means, science uses the term real as it is defined in any standard dictionary and applies that definition to it's explanations of the physical universe.

I ask you straight up. What does science say about time? You don't like that definition. Tough, that is what time is acording to science, and that is the same definition of time that is to used when someone speaks of time in context with science.

There is no mystery, no confusion about semantics, it is all right there.

Just because you do not like the definition of time according to science does not mean you just make up one that you do like. That is what believers do when defending their faith.

If you think time is a physical thing, show me the scientific evidence.

 

[p764rds]

Are all these word manipulations back & forth not just mental masturbation? Juggling with undefined terms & self referring abstractions. Does an illusion exist?

Sorry for the harsh words, but at this level, I think that the only arguments pro or con should come from mathematics. So if you want to prove wether or not spacetime exists (whatever that means), you have to do it mathematically.

Human language is not going to cut it, and this thread will go on forever without any progress. Just a lot of ping pong.

I'd rather ask another question. Is spacetime emergent or not? But then again, if you twist your mind long enough, maybe THAT's the definition of exists? In mathematics that is.

Anyway, I'm writing this because I get tired of reading people claiming to be able to prove this and that all the time. As far as I know, the only place you can prove anything is in math. No math, no proof.

/Frederic

I (& others) are saying that Universe is entirely mathematics based and uses information to implement that mathematics in a Von-Neumann-like way. Sorry if you don't like it... (I don't much either)

 

[john 8]

hmmmm interesting that 'you cannot prove space exists'. Also John8 seems to think like I think on this matter.

Lets take a simple scenario. Assume we have nothingness (i.e. what is 'outside' the Universe' - no space-time) and let's make an empty spherical space of radius 1 billion miles in the nothingness (OK, a flat euclidean space if you like - no gravity).

This 'space' is actually a mathematical statement (a sphere of radius r) and cannot physically exist. Isn't it logically absurd to have such a scenario, even in thought it does not work - because its mathematics not physicality. I am trying to suggest that physical 3d space is impossible to have and its actually in information where its easily produced and shaped.
So what have we got in our Universe that we think is x,y,z physical space? IMO its in information -information does not require physical space to exist, its also massless, and creates an illusion of 3D space very easily because it can implement mathematics.

Isn't it impossible to have an empty space located in nothingness - because its mathematics and not physical? All the space-time mathematics IMO start out with x,y,z (squared etc) without justifying the right to do that.


note: I am activley looking evidence in this direction - so all references and 'higher truths' gratefully received.

Amen brother! Let's have some scientific proof of the existence of space.

I am rather quite amused at all of the squirming that is being done by some to aviod the obvious.

Space is not a physical thing. Science says that space is not a physical thing. Common sense says that space is not a physical thing.

If any of you want me to shut up, then do your duty, and fullfill your obligation to show evidence that space is a physical thing according to science.

The burden of proof is on you. Stop goofing off and get a going. Crack open some books, get on the internet, gather your friends, do something that shows that you are able to defend your viewpoint and can scientifically prove your argument.

Why even be on this forum if you are not interested in learning more about science and are not willing to defend your points logically?

 

[JesseM]

Stop with this run around. Is a rock a physical thing according to science? Yes/No

Is light a physical thing according to science?

Science has defined itself and it's definitions.

I think most physicists would say that physics is basically just about coming up with mathematical models which are used to make accurate predictions about experimental results, I challenge you to point to any physics textbooks that define terms like "real" or "physical thing".

Are some of you on this thread just kids unfamiliar with physics and you are just here having fun?

I can not understand how some of you can say the things that you do if you had any basic understanding of science.

The same question might be asked of you, since the only sources you cite tend to be sources like dictionaries instead of scientific papers or textbooks. Have you ever taken any actual courses in physics, for example? You've shown in previous comments that you aren't familiar with some very basic ideas in classical mechanics, like the frame-dependence of energy (similarly, on this thread you pooh-poohed DaleSpam's definition of energy as force times distance by citing a dictionary which defined energy as 'capacity to do work', not realizing that 'work' is a technical term in physics meaning...force times distance!) Your dismissive, mocking attitude towards people who pretty clearly know the fundamentals of the subject a lot better than you reminds me of the psychological phenomenon discussed here where the people who know the least about a subject tend to have the most inflated self-assessments about their ability to evaluate claims related to the subject, because their own ignorance prevents them from realizing how little they actually know about it in comparison to others.

Science has defined what is real. This talk of philosophy is just an avoidance of my initial question. Look up the term real in a dictionary, that is what I mean by real.

Case in point. If you were more familiar with actual scientific literature like textbooks and papers, you'd probably notice that scientists almost never use a word like "real" (at least not in a physics context) because they realize how difficult it is to come up with a rigorous definition. For example, are forces "real"? They're certainly useful in Newtonian mechanics, but then you find that in other theories like quantum physics and general relativity the notion of forces is no longer used, and yet the different theories make nearly identical quantitative predictions in a range of circumstances. As I said, the essence of physics as seen by most physicists is just coming up with abstract mathematical models (as opposed to mechanical models that can be grasped conceptually in terms of 'real' entities and how they interact) that make accurate quantitative predictions. Consider the following discussion by Richard Feynman (in his book The Character of Physical Law), one of the great physicists of the 20th century:

On the other hand, take Newton's law for gravitation, which has the aspects I discussed last time. I gave you the equation:

F=Gmm'/r^2

just to impress you with the speed with which mathematical symbols can convey information. I said that the force was proportional to the product of the masses of two objects, and inversely as the square of the distance between them, and also that bodies react to forces by changing their speeds, or changing their motions, in the direction of the force by amounts proportional to the force and inversely proportional to their masses. Those are words all right, and I did not necessarily have to write the equation. Nevertheless it is kind of mathematical, and we wonder how this can be a fundamental law. What does the planet do? Does it look at the sun, see how far away it is, and decide to calculate on its internal adding machine the inverse of the square of the distance, which tells it how much to move? This is certainly no explanation of the machinery of gravitation! You might want to look further, and various people have tried to look further. Newton was originally asked about his theory--'But it doesn't mean anything--it doesn't tell us anything'. He said, 'It tells you how it moves. That should be enough. I have told you how it moves, not why.' But people are often unsatisfied without a mechanism, and I would like to describe one theory which has been invented, among others, of the type you migh want. This theory suggests that this effect is the result of large numbers of actions, which would explain why it is mathematical.

Suppose that in the world everywhere there are a lot of particles, flying through us at very high speed. They come equally in all directions--just shooting by--and once in a while they hit us in a bombardment. We, and the sun, are practically transparent for them, practically but not completely, and some of them hit. ... If the sun were not there, particles would be bombarding the Earth from all sides, giving little impuleses by the rattle, bang, bang of the few that hit. This will not shake the Earth in any particular direction, because there are as many coming from one side as from the other, from top as from bottom. However, when the sun is there the particles which are coming from that direction are partially absorbed by the sun, because some of them hit the sun and do not go through. Therefore the number coming from the sun's direction towards the Earth is less than the number coming from the other sides, because they meet an obstacle, the sun. It is easy to see that the farther the sun is away, of all the possible directions in which particles can come, a smaller proportion of the particles are being taken out. The sun will appear smaller--in fact inversely as the square of the distance. Therefore there will be an impulse on the Earth towards the sun that varies inversely as the square of the distance. And this will be the result of a large number of very simple operations, just hits, one after the other, from all directions. Therefore the strangeness of the mathematical relation will be very much reduced, because the fundamental operation is much simpler than calculating the inverse of the square of the distance. This design, with the particles bouncing, does the calculation.

The only trouble with this scheme is that it does not work, for other reasons. Every theory that you make up has to be analysed against all possible consequences, to see if it predicts anything else. And this does predict something else. If the Earth is moving, more particles will hit it from in front than from behind. (If you are running in the rain, more rain hits you in the front of the face than in the back of the head, because you are running into the rain.) So, if the Earth is moving it is running into the particles coming towards it and away from the ones that are chasing it from behind. So more particles will hit it from the front than from the back, and there will be a force opposing any motion. This force would slow the Earth up in its orbit, and it certainly would not have lasted the three of four billion years (at least) that it has been going around the sun. So that is the end of that theory. 'Well,' you say, 'it was a good one, and I got rid of the mathematics for a while. Maybe I could invent a better one.' Maybe you can, because nobody knows the ultimate. But up to today, from the time of Newton, no one has invented another theoretical description of the mathematical machinery behind this law which does not either say the same thing over again, or make the mathematics harder, or predict some wrong phenomena. So there is no model of the theory of gravity today, other than the mathematical form.

If this were the only law of this character it would be interesting and rather annoying. But what turns out to be true is that the more we investigate, the more laws we find, and the deeper we penetrate nature, the more this disease persists. Every one of our laws is a purely mathematical statement in rather complex and abstruse mathematics.

...[A] question is whether, when trying to guess new laws, we should use seat-of-the-pants feelings and philosophical principles--'I don't like the minimum principle', or 'I do like the minimum principle', 'I don't like action at a distance', or 'I do like action at a distance'. To what extent do models help? It is interesting that very often models do help, and most physics teachers try to teach how to use models and to get a good physical feel for how things are going to work out. But it always turns out that the greatest discoveries abstract away from the model and the model never does any good. Maxwell's discovery of electrodynamics was made with a lot of imaginary wheels and idlers in space. But when you get rid of all the idlers and things in space the thing is O.K. Dirac discovered the correct laws for relativity quantum mechanics simply by guessing the equation. The method of guessing the equation seems to be a pretty effective way of guessing new laws. This shows again that mathematics is a deep way of expressing nature, and any attempt to express nature in philosophical principles, or in seat-of-the-pants mechanical feelings, is not an efficient way.

It always bothers me that, according to the laws as we understand them today, it takes a computing machine an infinite number of logical operations to figure out what goes on in no matter how tiny a region of space, and no matter how tiny a region of time. How can all that be going on in that tiny space? Why should it take an infinite amount of logic to figure out what one tiny piece of space/time is going to do? So I have often made the hypothesis that ultimately physics will not require a mathematical statement, that in the end the machinery will be revealed, and the laws will turn out to be simple, like the chequer board with all its apparent complexities. But this speculation is of the same nature as those other people make--'I like it', 'I don't like it',--and it is not good to be too prejudiced about these things.

 

[p764rds]

I think most physicists would say that physics is basically just about coming up with mathematical models which are used to make accurate predictions about experimental results, I challenge you to point to any physics textbooks that define terms like "real" or "physical thing".

Back in the Quantum Physics section of this board a couple of people are heavily pushing Bohm Theory to bring back 'classical physics' and 'reality' ontology - by using the concept of pilot waves that travel FTL. The idea is that information from the 'effect' travels back in time to the cause using a 'reference frame' - weak causality is apparently OK provided it is valid from 'quantum preparation' to observation only. Then quantum bizarreness 'goes away'.


Thats why a lot of contributors are arguing (against) the 'real and physical' concept. So there is a debate at present revolving around 'real and physical' in the Quantum Physics section. (I am only in this section looking for good evidence against 'physicality of 3 dimensional space' for a couple of paragraphs of writing I am doing)

 

[JesseM]

Back in the Quantum Physics section of this board a couple of people are heavily pushing Bohm Theory to bring back 'classical physics' and 'reality' ontology - by using the concept of pilot waves that travel FTL. The idea is that information from the 'effect' travels back in time to the cause using a 'reference frame' - weak causality is apparently OK provided it is valid from 'quantum preparation' to observation only. Then quantum bizarreness 'goes away'.


Thats why a lot of contributors are arguing (against) the 'real and physical' concept. So there is a debate at present revolving around 'real and physical' in the Quantum Physics section. (I am only in this section looking for good evidence against 'physicality of 3 dimensional space' for a couple of paragraphs of writing I am doing)

The different "interpretations" of QM help back up the case Feynman makes in this paragraph of the longer quote I posted above:

It is interesting that very often models do help, and most physics teachers try to teach how to use models and to get a good physical feel for how things are going to work out. But it always turns out that the greatest discoveries abstract away from the model and the model never does any good. Maxwell's discovery of electrodynamics was made with a lot of imaginary wheels and idlers in space. But when you get rid of all the idlers and things in space the thing is O.K. Dirac discovered the correct laws for relativity quantum mechanics simply by guessing the equation. The method of guessing the equation seems to be a pretty effective way of guessing new laws. This shows again that mathematics is a deep way of expressing nature, and any attempt to express nature in philosophical principles, or in seat-of-the-pants mechanical feelings, is not an efficient way.

Crucially, none of the "interpretations" of QM actually makes any distinct predictions about experimental results. As he says, people's interpretations may help them get a "good physical feel" for QM, and as a philosophical matter it may even be that some interpretation really is a better reflection of "reality" than the others, but as far as actually making predictions you can get rid of all the "wheels and idlers" specific to a given interpretation (like the 'pilot wave' of Bohmian mechanics) and it makes no difference, all interpretations are equally useless in terms of making novel predictions, nor is there a shred of physical evidence that supports one interpretation over any other.

 

[john 8]

I think most physicists would say that physics is basically just about coming up with mathematical models which are used to make accurate predictions about experimental results, I challenge you to point to any physics textbooks that define terms like "real" or "physical thing".

The same question might be asked of you, since the only sources you cite tend to be sources like dictionaries instead of scientific papers or textbooks. Have you ever taken any actual courses in physics, for example? You've shown in previous comments that you aren't familiar with some very basic ideas in classical mechanics, like the frame-dependence of energy (similarly, on this thread you pooh-poohed DaleSpam's definition of energy as force times distance by citing a dictionary which defined energy as 'capacity to do work', not realizing that 'work' is a technical term in physics meaning...force times distance!) Your dismissive, mocking attitude towards people who pretty clearly know the fundamentals of the subject a lot better than you reminds me of the psychological phenomenon discussed here where the people who know the least about a subject tend to have the most inflated self-assessments about their ability to evaluate claims related to the subject, because their own ignorance prevents them from realizing how little they actually know about it in comparison to others.

Case in point. If you were more familiar with actual scientific literature like textbooks and papers, you'd probably notice that scientists almost never use a word like "real" (at least not in a physics context) because they realize how difficult it is to come up with a rigorous definition. For example, are forces "real"? They're certainly useful in Newtonian mechanics, but then you find that in other theories like quantum physics and general relativity the notion of forces is no longer used, and yet the different theories make nearly identical quantitative predictions in a range of circumstances. As I said, the essence of physics as seen by most physicists is just coming up with abstract mathematical models (as opposed to mechanical models that can be grasped conceptually in terms of 'real' entities and how they interact) that make accurate quantitative predictions. Consider the following discussion by Richard Feynman (in his book The Character of Physical Law), one of the great physicists of the 20th century:

I like you. You have made some interesting statements, something that contribues to the thread. You are articulate, and your communication is your own.

I think you said something about my antagonistic tone on this thread, your right, I will watch it.

You have mentioned many things that I would like to respond to, but it is getting late so I will have to respond later.

 

[p764rds]

You are completely wrong! You consider that the computer in front of you exists. When you go to the store to buy food, you are putting real physical things in your basket, not math equations. If someone were to ask you to pass the salt, you would grab the physical object and move it in a direction toward that person. You did all of this without using math to prove the existence of anything. You and I agree that we are breathing the substance known as air. I knew that this substance was real and existed before I understood math.

I read this on the Internet, I am not saying I agree, but I cannot think of anything you would agree with less...

"Its my view that you are made of data (numbers) and me too, and space, mass and energy -all numbers. We are all next to each other in a giant river of numbers in information space behind space-time. There is nothing that is not at heart a number. Data has no mass or spatial size and can implement the mathematics and logic required to run a Universe such as this one from information space. Data and time share a common basis. Leibnitz and Plato would probably agree."