Basic understanding of time

[studiot]

 

implicate order

 

The following has been derived from a summary of information taken from Amanda Gefter's recent book which is a mind blower.

 

Talking of books you might like the following (Cambridge 2008)

 

On Space and Time

 

Edited by Professor Majid

 

Essays by Connes, Heller, Majid, Penrose, Polkinghorne, Taylor

 

on the title subject.

[Implicate Order]

Thanks for the book reference studiot. I have just read the reviews and it is on its way from the tropical rainforest to my front door. Now I just need to hide the next credit card statement from my wife

[studiot]

 

Thanks for the book reference studiot. I have just read the reviews and it is on its way from the tropical rainforest to my front door. Now I just need to hide the next credit card statement from my wife

 

I'm glad there's someone else on the planet still prepared to read books.

 

[Wso]

Well the way that I understand it, time is seperate from space, seperate but still there is a relation. The way you have described gravity is not how it really works. What happens is that with more more speed you go through less time. If your assumption as to the slowing of particles due to heavier gravity were true, we would see that particles would all move less when near heavier planets then the temperature of these objects would be affected as well. Heat is basically just movement of molecules based on their energy, so if they moved less they would be cooling down, in reality they do not cool down when near high mass objects, so your assumption must be false.

Also, if you somehow stopped all particles from moving, time would continue to exist. Time is compleatly relative, meaning that depending on your point of view more or less time passes relative to others. Just because everyone covers their eyes does not stop light from existing. Time continues to exist, no matter what frame of view we look at it in.

[Schneibster]

Actually I think that "what is time" has a pretty concrete answer: it's the hyperbolic dimension, of the four large dimensions we experience in our universe. The other large ones are all circular. And the rest of the dimensions are all small.

[ajb]

Actually I think that "what is time" has a pretty concrete answer: it's the hyperbolic dimension, of the four large dimensions we experience in our universe.

You mean coordinate time here?

 

The time as measured by clocks is more subtle than that.

[PeterJ]

Got to agree with Swansont here. It is a metaphysical or logical problem.

 

Michel123456 - You say that the idea that time is an illusion is a defeat of our understanding. This may be so sometimes, but not necessarily. It is the idea proposed by many people who claim to understand time, together with a correlated claim, which would be the illusoriness of space. That is to say, both would be relative and emergent phenomena. This would be why neither time nor space make sense in philosophy once we have reified them.

[michel123456]

Got to agree with Swansont here. It is a metaphysical or logical problem.

 

Michel123456 - You say that the idea that time is an illusion is a defeat of our understanding. This may be so sometimes, but not necessarily. It is the idea proposed by many people who claim to understand time, together with a correlated claim, which would be the illusoriness of space. That is to say, both would be relative and emergent phenomena. This would be why neither time nor space make sense in philosophy once we have reified them.

Mmmm.

My opinion is that nobody so far has a good understanding of Time.

 

That Space & Time would be relative, I think it is a well established fact. Space & Time are relative.

That Space & Time would be emergent phenomena, yes that would be great, but I don't see why that would made both Space & time "illusions".

 

And finally, IMHO philosophy does not possess a good grasp upon Space & Time. Physics have surpassed philosophy in all weirdness, by far.

[PeterJ]

Yes, you're right. Emergence is not the same as illusoriness. Still, if something is emergent it is not real in some sense.

 

I would say that physics cannot be more weird that philosophy, since philosophy has to interpret and explain physics. I would agree, though, that the ideas of most scientifically respectable philosophers are not nearly weird enough to be correct or even of much use.

[swansont]

Yes, you're right. Emergence is not the same as illusoriness. Still, if something is emergent it is not real in some sense.

 

 

One has to take care whether the discussion is about a phenomenon being real (it physically exists) or the effects of it being real. Much of physics is not real, in some sense — electric fields and phonons (to name just two) are not real objects. They are the constructs we use to understand the effects of charges and vibrations, respectively. The effects that result from them are quite real.

 

As an experimentalist I don't really have a dog in the hunt of what's real and what's not, though there are those that spend much more time and effort pondering this. Whether phonons are real or not (or photons, for that matter, or even time) doesn't change any experimental results. Nature still behaves as if these things are real.

[PeterJ]

I'm not sure a thing has to physical in order to be real, except as a methodological restriction for physics. But we agree it's a metaphysical problem.

 

My view on the reality of time is expressed mathematically by Hermann Weil in his book on the continuum. He places the continuum prior to spacetime, as the phenomenon from which spacetime (and mathematics and intentional consciousness) is emergent.

 

Here physics merges into foundational mathematics and metaphysics, not to say religion and mysticism.

Edited February 20, 2014 by PeterJ

[Schneibster]

You mean coordinate time here?

 

The time as measured by clocks is more subtle than that.

 

Yes, of course.

 

OTOH occasionally we get to see time far away; like when SN1987a sequentially illumated gas and dust clouds it had emitted millions of years before. So we pretty much know that the rate of time was the same in the Magellanic Clouds 190 thousand years ago as it is here now. And this is by no means the only such measurement; there are others farther, that there were arguments about, until they could compare them with SN1987a and verify they were the same. That makes it a fair assumption it hasn't changed in the history of the universe within the distance we can ever see.

 

And here's a thought for the Thread Original Poster: this is the nature of time in the universe: the galaxies we can see at the furthest and dimmest at 13 billion years ago or so, only six or seven hundred million years past the Big Bang, will disappear over the next million years. And they will quite literally have "fallen off the edge of the observable universe," from our viewpoint; we can never see them again, we'd have to travel FTL to do so. That's the nature of the edge of the observable universe; and they fall out of time as well as out of space. So there's a part of the "Nature of Time," specifically how time appears to behave at the edge of the observable universe. HTH.

Edited February 20, 2014 by Schneibster

[michel123456]

 

Yes, of course.

 

OTOH occasionally we get to see time far away; like when SN1987a sequentially illumated gas and dust clouds it had emitted millions of years before. So we pretty much know that the rate of time was the same in the Magellanic Clouds 190 thousand years ago as it is here now. And this is by no means the only such measurement; there are others farther, that there were arguments about, until they could compare them with SN1987a and verify they were the same. That makes it a fair assumption it hasn't changed in the history of the universe within the distance we can ever see.

 

And here's a thought for the Thread Original Poster: this is the nature of time in the universe: the galaxies we can see at the furthest and dimmest at 13 billion years ago or so, only six or seven hundred million years past the Big Bang, will disappear over the next million years. And they will quite literally have "fallen off the edge of the observable universe," from our viewpoint; we can never see them again, we'd have to travel FTL to do so. That's the nature of the edge of the observable universe; and they fall out of time as well as out of space. So there's a part of the "Nature of Time," specifically how time appears to behave at the edge of the observable universe. HTH.

I know it is the standard point of vue.

But I really wonder why scientists are comfortable with that idea. To me it is monstrous, it should ring a bell because, as far as I can understand, it violates the copernican principle since it makes us today privileged observers of the universe.

[Strange]

I know it is the standard point of vue.

But I really wonder why scientists are comfortable with that idea. To me it is monstrous, it should ring a bell because, as far as I can understand, it violates the copernican principle since it makes us today privileged observers of the universe.

 

Privileged in what way? Every observer at every location (and at every point in time) will have an observable universe around them. That observable universe changes with the observer's location and over time. There are things we see now that won't be visible in future. There are things we can't see now that we will observe in future. None of these views is any better or more real than the others, so none is more privileged.

[studiot]

In relation to time and the foregoing discussion about physical and real, consider the following:

 

In space, positions x, (x+10) and (x-10) are all physical and real since I can move my boat from one to the other and back again as many times as I like and place it in any one of them if I am a good enough sailor.

 

But in time I can only observe my boat in the present. I cannot move it to the future or the past or observe it there.

 

So does this make the present physical and real, but the future and past non-physical and non-real?

[Strange]

So does this make the present physical and real, but the future and past non-physical and non-real?

 

No.

Edited February 21, 2014 by Strange

[studiot]

 

No.

 

 

 

Go on.

[Lizzie L]

 

Time still passes for stationary objects.

 

But would it still pass for an unchanging object?

[swansont]

 

But would it still pass for an unchanging object?

 

An unstable atom sitting, unchanging, eventually decays. So the answer to this is yes, or at least it appears that way.

[Lizzie L]

 

An unstable atom sitting, unchanging, eventually decays. So the answer to this is yes, or at least it appears that way.

 

Well,that was sort of the point behind my question. The OP suggested that "time is movement". It's not a big step to say that "time is change". So while you could say, as you do, that time flows for an atom, you support that case by showing that it eventually changes. But you could invert that, couldn't you, that and say that time is change?

 

And of course the interesting thing, for an single atom, is that its stable state is non-aging - you can't say, well, it's had a long time doing nothing, it's probably going to do something soon.

[Strange]

And of course the interesting thing, for an single atom, is that its stable state is non-aging - you can't say, well, it's had a long time doing nothing, it's probably going to do something soon.

 

You can say exactly that. It does nothing but, being unstable, it is going to do something soon. And if you want to make the argument (which usually comes up) that "the atom must be doing something because time is passing" then how about a fundamental particle such as a muon which, by defintion, has no internal structure but will still sit there dong nothing until it decays after about 2 microseconds.

[StringJunky]

 

You can say exactly that. It does nothing but, being unstable, it is going to do something soon. And if you want to make the argument (which usually comes up) that "the atom must be doing something because time is passing" then how about a fundamental particle such as a muon which, by defintion, has no internal structure but will still sit there dong nothing until it decays after about 2 microseconds.

But could it not be argued that it is doing something but we can't measure it ...something must be happening to cause the decay?

Edited February 21, 2014 by StringJunky

[Lizzie L]

Well I guess my point is that time is only meaningful relative to change. So I sort of agree with the OP (Substituting "change" for "movement")

[Strange]

But could it not be argued that it is doing something but we can't measure it ...something must be happening to cause the decay?

 

Well, you could argue that (and everyone who thinks that time doesn't exist does). But that is the fallacy of begging the question:

 

1. My relgion says that time is change.

2. Muons appear not to do anything, but they still experience time.

3. That means muons must be changing in ways we cannot perceive.

4. Therefore time is change.

 

If you are more interested in faith-based belief than science, that is probably quite satisfying.

http://en.wikipedia.org/wiki/Begging_the_question

Edited February 21, 2014 by Strange

[michel123456]

 

Privileged in what way? Every observer at every location (and at every point in time) will have an observable universe around them. That observable universe changes with the observer's location and over time. There are things we see now that won't be visible in future. There are things we can't see now that we will observe in future. None of these views is any better or more real than the others, so none is more privileged.

That is not true.

Common understanding says that we are able to discern the Big bang while future astronomers (in billion years from now) will not.

In that way, we are privileged.

 

IOW it means that we have swallowed that we are anywhere in space ( copernican principle) but we haven't swallowed yet that we are also "anywhere" in time.

Because the common understanding states that we are not "anywhere" but at a very specific location in time.

IMHO it must be wrong.

We must be anywhere both in space and in time.

Edited February 21, 2014 by michel123456