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Uclock
2007-Jan-17, 01:47 PM
I am debating at geometric theory of gravity called True Relativity on the ATM site and during our ‘discussions’ I have asked these three simple questions on spacetime which those opposing TR (True Relativity) seem unwilling or unable to answer.

I would appreciate it if those who use the Q&A site would enlighten me with their thoughts on the subject of spacetime.

These are:

1) Is space and time the same entity?
2) Is there a flow of time?
3) Is there a flow of space?

If you do provide answers, could you please give explanations with your answers and state whether you are a professional or an amateur.

I will answer these questions myself according to TR once I have read everyone’s thoughts on the subject.

Thank you.

Tony

Celestial Mechanic
2007-Jan-17, 02:19 PM
The intent of this post does not seem to be obtaining an answer to these three questions but rather a way of continuing the debate over Uclock's ideas. There already is a thread devoted to that debate, therefore this thread should be locked.

Kaptain K
2007-Jan-17, 02:40 PM
1) Is space and time the same entity?
Are heads and tails the same entity?

2) Is there a flow of time?
Define "flow".

3) Is there a flow of space?
Define "flow".

Otherwise, I agree with Celestial Mechanic.

antoniseb
2007-Jan-17, 02:44 PM
The intent of this post does not seem to be obtaining an answer to these three questions but rather a way of continuing the debate over Uclock's ideas. There already is a thread devoted to that debate, therefore this thread should be locked.
I agree. Uclock can PM me to make the case that this is not what he/she is doing.

antoniseb
2007-Jan-18, 11:24 PM
I got a PM from Uclock indicating that he wants to see what mainstream scientists think about these things, and he has no plan to take this thread into his ATM area of interest.

I'm asking anyone participating to try and stick to mainstream discussion of this topic.

Squashed
2007-Jan-19, 12:38 AM
I am debating at geometric theory of gravity called True Relativity on the ATM site and during our ‘discussions’ I have asked these three simple questions on spacetime which those opposing TR (True Relativity) seem unwilling or unable to answer.

I would appreciate it if those who use the Q&A site would enlighten me with their thoughts on the subject of spacetime.

These are:

1) Is space and time the same entity?
2) Is there a flow of time?
3) Is there a flow of space?

If you do provide answers, could you please give explanations with your answers and state whether you are a professional or an amateur.

I will answer these questions myself according to TR once I have read everyone’s thoughts on the subject.

Thank you.

Tony

Well, I'll take a stab at it, even though I do not believe in the mainstream view/pedagog.

Spacetime is supposed to be a single entity with 4 dimensions: the 3 spatial and one called "time".

Time generally always seems to flow in one direction but according to some calculations by publius it can jump backwards. Also time supposedly goes backwards inside the event horizon of a black hole - at least that is what popular literature states.

Space flows at least in the manner called "expansion" or "inflation" and these two types of flow are directly additive to velocities (without the need for relativistic velocity addition formulas). This means that when space is flowing one way and light is moving in the same direction then the resultant speed of the light is "faster-than-light".

I can elaborate further but, alas, without calculations to prove what I describe.

btw: I am not a mainstream scientist.

publius
2007-Jan-19, 12:43 AM
Well, I'll take a stab at it, even though I do not believe in the mainstream view/pedagog.

Spacetime is supposed to be a single entity with 4 dimensions: the 3 spatial and one called "time".

Time generally always seems to flow in one direction but according to some calculations by publius it can jump backwards. Also time supposedly goes backwards inside the event horizon of a black hole - at least that is what popular literature states.

Space flows at least in the manner called "expansion" or "inflation" and these two types of flow are directly additive to velocities (without the need for relativistic velocity addition formulas). This means that when space is flowing one way and light is moving in the same direction then the resultant speed of the light is "faster-than-light".

I can elaborate further but, alas, without calculations to prove what I describe.

btw: I am not a mainstream scientist.


Squashed,

No one's proper time in his own frame ever runs backwards. What can jump backwards is one observer's sense in his frame of what another distant clock is doing. That's a consequence of a jump in reference frame.

And what happens inside an event horizon is space and time "flip", or better one spatial direction, radius flips with time. Our time outside becomes a spatial direction inside, and our radius direction of space becomes the time dimension.

-Richard

George
2007-Jan-19, 01:09 AM
2) Is there a flow of time?
I would think the "arrow of time" would help here. It involves entropy such that order marches toward disorder; eggs, once broken, to not unbreak.

Ken G
2007-Jan-19, 03:46 AM
By the way, if "professionals" seem unwilling to answer those questions, it is not because they have something to hide, or because the questions are embarrassing in any way. It's simply because they are not well posed scientific questions. I could equally ask what is the sound of one hand clapping, and get similarly limited response.

Uclock
2007-Jan-19, 02:20 PM
Kaptain K


Quote:
1) Is space and time the same entity?

Are heads and tails the same entity?

Good point, a coin can be considered the same entity with two sides, one heads and one tails. If you split the coin you only end up with two halves of a coin. I think mainstream physics tends to think of spacetime like this.


Quote:
2) Is there a flow of time?

Define "flow".

Flow is a movement in one direction like water flowing down a drain pipe, the flow of traffic and such. In the case of time, does it flow from the past towards the future, if so is that flow real physical thing or is our mind just putting things in some sort of order?


Quote:
3) Is there a flow of space?

Define "flow".

The same as defined in (2), a movement in a particular direction.

Tony

Uclock
2007-Jan-19, 02:55 PM
Squashed


Well, I'll take a stab at it, even though I do not believe in the mainstream view/pedagog.

Thanks



Spacetime is supposed to be a single entity with 4 dimensions: the 3 spatial and one called "time".

Yes, this seems the mainstream view.



Time generally always seems to flow in one direction but according to some calculations by publius it can jump backwards. Also time supposedly goes backwards inside the event horizon of a black hole - at least that is what popular literature states.

I agree, the popular literature does seem to follow the mainstream view and I take it publius has used four dimensional spacetime or string theory to make his calculations but you are right, time seems to flow in one direction so do you think that this flow is a real physical phenomenon or is it just our mind putting things in order?



Space flows at least in the manner called "expansion" or "inflation" and these two types of flow are directly additive to velocities (without the need for relativistic velocity addition formulas). This means that when space is flowing one way and light is moving in the same direction then the resultant speed of the light is "faster-than-light".

So are you saying that space does flow and linking this to the cosmic expansion?



I can elaborate further but, alas, without calculations to prove what I describe.

It does not matter really, I am after your thoughts not calculations and I would be grateful if you can elaborate.



btw: I am not a mainstream scientist.

That’s fine, non-mainstream, amateur or professional all I want is your thoughts.

Tony

grant hutchison
2007-Jan-19, 03:07 PM
In the case of time, does it flow from the past towards the future, if so is that flow real physical thing or is our mind just putting things in some sort of order?That second option is a little tricky to get working properly. For our minds to "put things in some sort of order" they'd need to order events by some sort of internal time: first we visit this event, then we visit that event ...
Or you might imagine that time doesn't exist, but that our entire lives are timelessly present in some super-dimension as a huge random jumble of every single moment we experience in a life-time; like a spilled photo album, perhaps. Each moment contains within it memories of all events we think of as "previous" at that moment, but no events we thing of as "future". But that's like the argument that God created the Universe 6000 years ago with everything in place to make it look 13.7 billion years old: we can't tell the difference, so we might as well try to work out the rules as they are represented to us.
So it seems to me that "our minds just putting things in some sort of order" makes no scientific prediction that could be distinguished from the passage of time as we believe we experience it.

Grant Hutchison

Nereid
2007-Jan-19, 03:11 PM
I am debating at geometric theory of gravity called True Relativity on the ATM site and during our ‘discussions’ I have asked these three simple questions on spacetime which those opposing TR (True Relativity) seem unwilling or unable to answer.

I would appreciate it if those who use the Q&A site would enlighten me with their thoughts on the subject of spacetime.

These are:

1) Is space and time the same entity?
2) Is there a flow of time?
3) Is there a flow of space?

If you do provide answers, could you please give explanations with your answers and state whether you are a professional or an amateur.

I will answer these questions myself according to TR once I have read everyone’s thoughts on the subject.

Thank you.

TonyIn another Q&A thread (http://www.bautforum.com/showthread.php?t=52091), I started to answer (http://www.bautforum.com/showpost.php?p=900993&postcount=9) a similar question. I feel that what I wrote there is pertinent here too, so I will repeat it:

What follows may not be the kind of answer you are looking for, Uclock, but it is (I hope) entirely relevant within the framework of modern physics.

General Relativity (GR) is a theory within (modern) physics.

It's domain of applicability is, naively, unlimited; however, it is incompatible with another (set of) theory(-ies) in modern physics, quantum mechanics (QM), and the regimes in which the incompatibility is intolerable include the Planck regime.

GR has been tested, both here on Earth, within the solar system, within our own galaxy, and in the universe at large. So far, it has passed every test, with flying colours.

GR's incompatibility with QM cannot, at present, be tested, either in any Earth-bound lab or experiment, or by any astronomical observation ... to date.

GR 'talks about' space and time.

To the extent that a theory of physics, which seems to be an accurate description of everything we have ever observed, to date - period - and which includes 'an account of' space and time is relevant to the questions such as the ones in the OP, then we may answer all those questions by asking an equivalent set of questions, re-cast in 'the language of GR'.

What might those re-cast questions be?

....

Before proceeding to try to answer them, could you, Uclock, please state in what way the approach to providing an answer (outlined above) would be unsatisfactory to you?

01101001
2007-Jan-19, 05:18 PM
Before proceeding to try to answer them, could you, Uclock, please state in what way the approach to providing an answer (outlined above) would be unsatisfactory to you?

I can understand why you're curious, but should such contraints be requested, and if provided in any case, need they be respected?

If I were to ask: what is a resolution to the so-called Twins Paradox; please don't use the letters e and s or the number 2 in your answer, and, oh yeah, leave out all that relativity stuff, should answerers actually be so constrained? I hope not. A question usually has an actual audience larger than the single poser.

It seems lately that Q&A has gotten a spate of Jeopardy-like ATM statements in the form of a question. Attempting to clarify the boundaries of acceptable answers to any question, just seems like asking for yet more.

Nereid
2007-Jan-19, 05:47 PM
I can understand why you're curious, but should such contraints be requested, and if provided in any case, need they be respected?(my bold)

No, to both.

However, if there is a question posted in this Q&A section, I feel it important to establish just what sort of answer would make sense to the one who posed it, and, perhaps, to any other BAUT member posting here.

In this case, if Uclock's (or anyone else's) perspective is but weakly tied to how 'space', 'time', and whether either can 'flow' (whatever that may mean) are understood in the best theories of physics/science today, then there seems little point proceeding to first re-cast the questions in terms of GR, and second try to answer them. And that's what seems to have happened in the the thread with similar questions posed by ngeo.

And, on a personal note, if there is nothing more than a weak interest in such an approach, then I can ignore the thread entirely - as I think it's quite clear from my posting history, I have little interest, here in BAUT, in going beyond the bounds of the best we can do in astronomy, astrophysics, cosmology, etc, as science, today
If I were to ask: what is a resolution to the so-called Twins Paradox; please don't use the letters e and s or the number 2 in your answer, and, oh yeah, leave out all that relativity stuff, should answerers actually be so constrained? I hope not. A question usually has an actual audience larger than the single poser.

It seems lately that Q&A has gotten a spate of Jeopardy-like ATM statements in the form of a question. Attempting to clarify the boundaries of acceptable answers to any question, just seems like asking for yet more.It's a bit of a worry, but I feel it's better done like this, than have long ATM threads that thrash around for page after page ... only to show that there is no real ATM idea, just some confusion over some very basic ideas in modern physics (which could have been cleared up within a handful of posts, as a decently worded question in the Q&A section).

However, I think we have some way to go to having the OP questions phrased in a less ATM way ...

Cougar
2007-Jan-19, 06:05 PM
1) Is space and time the same entity?
No. These used to be thought of as absolute, but Einstein pointed out that they are NOT absolute. Time, length, mass can vary depending on the frame of the observer.

2) Is there a flow of time?
You call this a "simple question"? :o If you look at Brian Greene's The Fabric of the Cosmos; Space, Time, and the Texture of Reality [2004], you will find several chapters (or is it the whole book?) talking about this question and its implications. A simple thought-example that complicates the question: If there is an advanced form of life in a galaxy 65 million lightyears away who have developed very powerful telescopes, they could NOW be viewing dinosaurs on Earth. So....

3) Is there a flow of space?
Huh?

Ken G
2007-Jan-19, 06:18 PM
Personally, I think it's fine for the moderators to try and "coax" the kinds of questions to be posed in a more constructive way, as the only real alternative is banning the posters who are creating a recent glut of nonscientific questions. It seems to me that despite this spate, the posters are by and large willing to hear scientific answers, and if they learn how to post scientific questions along the way, that may benefit them even more than being given answers they can't understand until they better understand what science is. I think that's what Nereid is trying to accomplish.

As for the questions on this thread, I was originally put off by the word "unwilling" in the OP, but I'm ready to accept that perhaps Uclock is entirely sincere in his/her desire to get some insightful answer, rather than setting a "trap" for an ATM excursion. I could be wrong, but I do think that the apparent "flow" of time is a valid science question, and I know it has been addressed on here before but each time there is some slightly new flavor to the discussion.

If I were to give my take on the flow of time (and apparently I am), I would say that "time" is a word, invented by human intelligence to label a way of organizing phenomena to make them "make more sense". This is the scientific concept of time, because that's just what science always does. But the question of whether or not time is "real", or just an organizational principle, is purely a metaphysical question. All physics needs is that the concept be useful. Nevertheless, the exercise of looking at why the concept is useful informs the metaphysics of time, and excursions into metaphysics are not exactly ATM, they're just kind of subjective. Maybe the forum needs a "metaphysics" area for such posts, but since there isn't, it could be viewed as relevant to Q&A.

So why is time a useful concept? I see three important principles of physics that relate: locality, continuity, and cause and effect. Locality means that we can unambiguously and objectively say that two events occurred at the same place and the same time. All events that do not have that particularly simple relationship are more difficult to interrelate, but local events are pretty clear. So that is one basis of time: a part of what is required for events to be local with each other. Then there's the issue of continuity, which is a way of generalizing the concept of locality to near-locality. How do we quantify the near-locality of two events that are not quite local? Those are the concepts of separation and elapsed time. So elapsed time is then a quantification of that part of the near-locality, and although we know from relativity it is frame-dependent, nevertheless it is quite important. The reason near-locality is so important is that most of physics is expressed in terms of differential equations, meaning that local events lead to nearly-local events. There is a kind of continuity in physics, that if we did not have the principle of time, we could not appreciate the apparent crucial importance of this property.

Time is part of how we quantify the near-locality, and it goes right into those differential equations. What makes it physical is that it is measurable-- we have clocks. What makes clocks useful goes back to the principle of locality-- a clock in the same place and time as some process will proceed similarly as that process, so the time measured by the clock is relevant to that process, they are intimately related for reasons that we don't know but can only say it's because they are local to each other.

Finally, we have the principle of cause and effect. Without that principle, one could say that even the differential equations are just a way of organizing things, like Grant's photo album that is ordered so as to make mathematical sense but which can just as well exist in a scrambled form. But cause and effect seems to be one of the deepest principles of physics-- there is a logical connection between something that can be a cause and something that can be an effect, and there is also an order to it: the cause must precede the effect, in all reference frames and for all observers. When you tack on the principle of locality, you get the necessary unification of time: if A causes B, and B is local to C, and C causes D, then even though A doesn't directly cause D, it must precede D. That's time in a nutshell, the rest is just measurement, quantification, and deriving the differential equations of physics.

So given all this, can we now say whether or not time is real, or if it's just an organizational principle? It's still metaphysics, so no, we can't say objectively, but we can make the argument that it is a very special type of organizational principle. You can organize your photos chronologically, or you can organize them alphabetically by topic, but the key difference is that if you organize them chronologically, then the order means something physically-- anything you see in an earlier picture could affect something in a later picture, and it could be happening in the subject of the picture or some distant barely noticeable background, it doesn't matter. The cause and effect unifies the order of all the events that are happening, and I would say that the "reality" of time hinges on that property.

As a parenthetical note, it is important to repeat that "chronological order" has an ambiguity to it, in that if you have two photos of events in the universe that are not causally related (light could not have gone from one to the other), then the time ordering of those photos is arbitrary. Reality just doesn't care, it's up to you, alphabetical or however you like. So our everyday concept of time is clearly imposing more order onto reality than is really there-- an organizational principle that is not so absolute as it seems.

Amber Robot
2007-Jan-19, 06:54 PM
GR has been tested, both here on Earth, within the solar system, within our own galaxy, and in the universe at large. So far, it has passed every test, with flying colours.

Except for those cases for which dark matter was invented.

Uclock
2007-Jan-21, 12:50 PM
There have been some good replies to the questions posed and it seems there is no real consensus on the subject of spacetime. Some of you consider spacetime to be the same entity but not all posters agree, although they say you cannot have space without time.

The subject of the ‘flow of time’ or the arrow of time seems to be a very difficult subject for people to express in words using their own experience of time.

As to whether or not space also flows, most seem to regard it as a metric and it may be that the cosmic expansion is some sort of flow of space.

All are interesting and valid views according to the individual’s perspective and of course their education because we usually believe everything we are taught.

Personally I believe that, as the Universe is made mainly of space then to really understand the Universe we must understand what space itself actually is. Is it some sort of aether or could it be some sort of field or is it really nothing at all? Either way physics has given it dimensions and uses the metric to model it.

My personal opinion is that to try and understand space, time must be the key but if there is no consensus as to whether or not time flows how are we ever to really understand spacetime and crucially gravity, because as Einstein believed, and for what it’s worth I agree, gravity is a distortion of spacetime.

Just a little food for thought.

Your views are very interesting so please keep them coming.

Tony

sirius0
2007-Jan-21, 08:53 PM
Squashed,

No one's proper time in his own frame ever runs backwards. What can jump backwards is one observer's sense in his frame of what another distant clock is doing. That's a consequence of a jump in reference frame.

And what happens inside an event horizon is space and time "flip", or better one spatial direction, radius flips with time. Our time outside becomes a spatial direction inside, and our radius direction of space becomes the time dimension.

-Richard

Wow this is why I love this board!

Uclock
2007-Jan-29, 01:07 PM
The three questions posed were.

1) Is time and space the same entity? Yes
2) Does time flow? Yes
3) Does space flow? Yes

As Nereid and others have pointed out this thread overlaps physics and philosophy but in my opinion this is not a bad thing.
The language of physics is math and it is most definitely needed as a way of ‘transmitting’ knowledge by precise measurements of our Universe but after all is said and done it is still only a language. Where physics is useful to help our understanding of the Universe is in the measurement of it.

My personal belief, for what it’s worth, is physics has become over reliant on mathematics and has allowed ‘the language of math’ to take the lead.
From posing the questions above I have noticed that nearly everyone talks in terms of what they have been taught, this is not a criticism it is just an observation because we all tend to do that.

In my opinion the mind is far more powerful than any math because it has the ability to reason, some peoples ability to reason is better than others and although this forum deals with science I take the view that philosophy can sometimes guide people in the right direction.

The view that space and time must be treated as the same entity yet we treat time as a separate dimension ‘four dimensional spacetime’ seems illogical to me but this view is passed down the ages and is really only convention.

It is possible using only simple geometry to model three dimensional spacetime, including the gravitational field of any object with mass. Viewing spacetime in this way opens up possibilities that do not exist in four dimensional spacetime.

The most striking being that gravity becomes time dependant so the size of the gravitational field of any object will depend on the age of the Universe which means dark matter is not required to explain the almost fixed rotation of stars in spiral galaxies.

Another consequence of viewing spacetime as three dimensional is that faster than light travel becomes a distinct possibility and there also appears to be link between three dimensional spacetime and quantum entanglement.

What is quite remarkable about viewing spacetime as three dimensional is that the math does not break down at the extremes of this Universe and it can model spacetime inside black holes and even the events surrounding the big bang.

As I am the only person studying three dimensional spacetime I do not expect physicists to believe it can work but I can assure you it does and it works extremely well.

Three dimensional spacetime can be experimentally tested and if it is the way our Universe works then GP’B’ will return a higher value for frame dragging than is expected using GR. There are also other experiments that would back up the argument that spacetime is three dimensional not four dimensional.

It is these reasons above that lead me to answer ‘yes’ to all three of the questions posed on this thread.

I hope other people will continue to post their thoughts.

Tony