Time Explained

[ChildInAZoo]

The clocks runs at different speeds because they are in motion relative to each other, that's all.

But do they? 'a's clock' can't both run faster AND slower than 'b's'.
If SR says that both clocks run faster AND slower at the same time, then SR is not giving us reality. It may WORK both ways, but that's not the same as reality.
I did ask if the clocks ACTUALLY run at different speeds.

SR does not say that both clocks run faster and slower. SR tells us that, if we make one choice for making a description, then clock a runs faster than clock b. It also tells us that if we make another choice for making a description, then clock b runs faster than clock a. Many people naively assume that there is some way that they can describe all things in one master way that describes all things for all time. This is not possible.

SR is saying that there is no 'actually', only an infinite number of 'apparently's, all perfectly valid, depending on your choice of reference frame.
I want to know what ACTUALLY happens. And a clock can't ACTUALLY run faster AND slower than another at the same time.

SR is saying that what actually happens is what happens at any event. If you want to coordinate between events that are separated by distance and time, there is no one way of actually coordinating between events. The actual coordination between events is governed by the causal and affine structures of space and time.

I'm not saying SR is wrong, I'm saying it works perfectly, but it's not reality. Obviously, clocks are just there to measure time. So SR is really saying that time for 'a' can run slower AND faster than 'b', simultaneously.

See, there you are, using the word "simultaneously" in a way that it turns out you cannot use it. This is one of the main lessons of SR: we have to be very, very careful about what it means for two things to be simultaneous.

I appreciate that we can never experience true simultaneousness, ( is that a word? ) but that doesn't mean it's not there, or that we should ignore it.

I don't know what "true simultaneousness" is, but if it has no effect on the world whatsoever, then why say that it exists?

[mistermack]

Many people naively assume that there is some way that they can describe all things in one master way that describes all things for all time. This is not possible.

Well, that is exactly the point I am making. I agree this is not possible. It's not possible for us to describe, only because we don't have the tools. But is that a good enough reason to ignore it? To pretend that relativity IS reality?
To me, by all means accept that relativity is the only tool we have, but don't confuse it with reality.

I don't know what "true simultaneousness" is, but if it has no effect on the world whatsoever, then why say that it exists?

Because it exists. The fact that we don't have the tools to experience it doesn't mean it doesn't exist.
.

[ChildInAZoo]

Well, that is exactly the point I am making. I agree this is not possible. It's not possible for us to describe, only because we don't have the tools. But is that a good enough reason to ignore it? To pretend that relativity IS reality?
To me, by all means accept that relativity is the only tool we have, but don't confuse it with reality.

Relativity theory is based on what the world tells us is the limits on the best possible descriptions. What more could there be to reality than the best possible descriptions? You want to say that, despite the fact that it looks like there is not one special relationship between events, and even though rejecting the claim that there is one special relationship between events allows us to perform feats of wonder and astonishment through physics, we should nonetheless believe that there is one special relationship between events, even though it allows us to do nothing in physics.

I don't know what "true simultaneousness" is, but if it has no effect on the world whatsoever, then why say that it exists?

Because it exists. The fact that we don't have the tools to experience it doesn't mean it doesn't exist.

Would you accept the argument that we should believe in God because god exists?

[Farsight]

Farsight, thanks for that. But I'm not sure the first half of what you said makes a difference, and I'll have to work on the second half.
Picture one of the clocks. If you say it's travelling at 100,000 mph, the 'light' inside the atoms is travelling laterally, so rotates less, showing slower apparent time?
If it's stationary, it rotates more. So the question remains, which ACTUALLY happened? SR is saying both are valid. But are both circumstances REAL?

All that's happening is that the "light" in a "motionless" atom is going round and round in a circular path. But if the atom is moving, that light has to be going round and round in a helical path. It's still going at c, so it takes longer to complete one revolution because it got to move a longer distance. Hence it's "time dilated".

It's the same principle as the light bouncing back and forth in the parallel-mirror light clock. If the clock is motionless, the light is going back and forth like this ║. But if the light clock is moving, that light has to be going back and forth in a zigzag path like this /\/\/\/\/\/\. It's still going at c, so it takes longer to complete one bounce because it got to move a longer distance. Hence it's "time dilated".

You have problems deciding on what's real or not because of what pair production is telling you. You are made of light. Think of all of the electrons and protons and neutrons in your body as light going round in loops. Then boil it down to one single electron, a "rotating ring of light", and think of this electron as yourself. If you move through this real universe, the path of any one point around the circumference of this ring isn't circular, it's helical. When you look at all points round the circumference and slot all the helical paths together, the reality is that you're smeared out into a cylinder. But you don't know it. As far as you're concerned, you're still a ring. You can't see that you're a cylinder. You can't see that you're smeared out. You get a different view of reality. And you think it's real, because as far as you're concerned, it is.

Don't doubt special relativity, Mistermack. It's right, it works. And when you understand what pair production is telling you, you can understand why.

[mistermack]

Relativity theory is based on what the world tells us is the limits on the best possible descriptions. What more could there be to reality than the best possible descriptions? You want to say that, despite the fact that it looks like there is not one special relationship between events, and even though rejecting the claim that there is one special relationship between events allows us to perform feats of wonder and astonishment through physics, we should nonetheless believe that there is one special relationship between events, even though it allows us to do nothing in physics.

Noooooooooo, I made it perfectly clear that I know that relativity is the only tool that works, and I accept that it does a fabulous job of calculating the physics of the universe. I'm not saying we should start using absolutes, because we haven't got them. I'm just saying 'use relativity by all means, but don't pretend it's reality'.
We know distant galaxies are not where they appear, we accept they are somewhere else, even if we can never see them there.

Would you accept the argument that we should believe in God because god exists?

Nope, but do you accept that the far-away galaxy you see is somewhere else, AT THIS INSTANT, even if you can't possibly prove it?
.

[LaMont Cranston]

Farsight, MrJobby and Others, As somebody who is a seeker of information and an interested student about this subject, I am doing the best I can to keep up with the math and science. My area of expertise has more to do with how humans behave and the nature of consciousness, and I have a questions regarding that.

From what I can tell, as human beings, we exist in present time and have experiences moment to moment. From present time we remember the past as memories, and we have expectations about what the future might be like, but we are still doing it now. We can take an event, (i.e. The Big Bang, the publishing of Einstein's works, whatever) and describe what has transpired since that thing happened, but we are still at here and now looking back at there and then.

If this is true, do the past and the future require consciousness to exist? Do these other tenses of time exist outside the mind of somebody's subjectivity? The state of the cosmos is what it is at this moment...what exists exists...but, above and beyond that, do the past and future exist?

I look forward to hearing from all of you!

[ChildInAZoo]

Noooooooooo, I made it perfectly clear that I know that relativity is the only tool that works, and I accept that it does a fabulous job of calculating the physics of the universe. I'm not saying we should start using absolutes, because we haven't got them. I'm just saying 'use relativity by all means, but don't pretend it's reality'.

Then I have no idea what you mean and I fear that you have no better idea what you mean.

Would you accept the argument that we should believe in God because god exists?

Nope, but do you accept that the far-away galaxy you see is somewhere else, AT THIS INSTANT, even if you can't possibly prove it?

But what do you mean by "AT THIS INSTANT"? I believe that distant galaxies exist at distant places, but I could use a number of choices of "instant" to say this. I do not accept that there is one special "AT THIS INSTANT". You seem to believe that, despite everything we seem to be able to learn, there is nonetheless this mystical "AT THIS INSTANT" that plays no role in anything that happens but that is nonetheless there. You are saying that we should start using absolutes, but I'm not sure in what sense you are saying this.

(NB: I frankly cannot understand what Farsight is saying or what it has to do with relativity theory, aside from the fact that he is discussing light and light clocks. He may be trying to produce some sort of interpretation of relativity theory, but as far as I can tell, nothing that he says is required to understand relativity theory. )

[mistermack]

Farsight, I accept all that. It's exactly what I've thought all along. BUT, SR is saying that I'm a ring, I'm a short cylinder, I'm a million billion different cylinders all simultaneously.
That's my problem.

[mistermack]

You are saying that we should start using absolutes, but I'm not sure in what sense you are saying this.

No, I'm not saying that. I'm very definitely saying we should USE relativity, we should NOT be trying to use absolutes, because we don't have the tools. I'm just saying that we should just be aware that we are using apparent reality, not REAL reality.

To see what I'm getting at, imagine that today it was announced that phyicists had discovered a new form of 'light' we call Light2.
Light2 is of a totally new nature, and as far as we can tell, the speed of L2 is infinite. It turns out that the universe is bathed in L2, and with new L2 cameras we can now see all the farthest galaxies and stars as they are this very instant, with no detectable delay.
Also, we can now make clocks that use L2, that never vary, keep perfect universal time, and are totally independent of gravity and motion. Also, L2 waves conveniently have markers every centimetre that give us a perfect, invariable ruler.

The big question is :
Which set of tools would you say gives you a true picture of reality?
L2, and L2 clocks and L2 rulers, or the old Light, with finite speed, and with clocks that vary with velocity?.
.

[mistermack]

If you answer 'L2' would give the true picture of reality, try applying it to the two clocks.


Two experimenters, 'a' and 'b', traveling towards each other at a closing speed of 100,000 mph, carrying identical stopwatches. They are both using the same reference clock, an extremely distant pulsar, both observing it using L2. When they pass each other, they start their stopwatches. When the pulsar has revolved one million times, they stop their stopwatches.
The question is, will both stopwatches show the same elapsed time, or not?
If you consider 'a' to be at rest, and 'b' to be moving at 100,000 mph, you would expect 'b's watch to be running slow.
If you consider the opposite, then 'a's watch should be slow.
But special relativity says that both cases are equally valid. Neither watch has undergone any acceleration, while making it's measurement. So each watch should be running faster, and slower, than the other. We know this is impossible, so it can only be that both cases are NOT equally valid.

[Brain Man]

Farsight, MrJobby and Others, As somebody who is a seeker of information and an interested student about this subject, I am doing the best I can to keep up with the math and science. My area of expertise has more to do with how humans behave and the nature of consciousness, and I have a questions regarding that.

From what I can tell, as human beings, we exist in present time and have experiences moment to moment. From present time we remember the past as memories, and we have expectations about what the future might be like, but we are still doing it now. We can take an event, (i.e. The Big Bang, the publishing of Einstein's works, whatever) and describe what has transpired since that thing happened, but we are still at here and now looking back at there and then.

If this is true, do the past and the future require consciousness to exist? Do these other tenses of time exist outside the mind of somebody's subjectivity? The state of the cosmos is what it is at this moment...what exists exists...but, above and beyond that, do the past and future exist?

I look forward to hearing from all of you!

You arent actually in present orientation at all. What are your plans for this week ? Do you have to go to work, remember whats expected of you, plan for that. Utilize your past experience for that. Get promoted on the basis of your experience.

What are you capable of without past and future encoding structuring your life. If any of those future/past parts of your brain did not work you would have Anterograde or retrograde amnesia. Only with those two conditions together or the drugs that induce them can you actually be completely in the present.

[Brain Man]

Farsight..come back.. youre the time expert...Help us out with Barbours "Alpha points" ....

Sorry Mr Jobby. I'll move rationalia up my favourites list. What are those alpha points? I read Julian Barbour's The End of Time back in 2001 and found it very interesting. In 2006 I got into a spat about the speed of light, whereafter I thought time is the key and resolved to really look into it. So I read The End of Time again, plus Paul Davies' About Time along with other material, and then wrote the first version of Time Explained. I don't concur with Barbour's take I'm afraid, which is rather a block-universe timeless view. I take a more mundane view. We see space and motion through it. That's it.

Barbour doesn't do away with time completely. He states that time is localized into capsules by common points of reference he calls alpha points within a space called platonia and time is motion within that referenced to the alpha point. So thats useful in itself, but i get the impression he takes it too far and does away with time completely for a cocktail of intellectual challenge and perhaps there may be a touch of scientific sensation seeking in there, whether public or personal is anybody's guess.

There's some interesting stuff kicking around about supermassive black holes, such as they may even be involved in galaxy formation. However black hole spin is rather... interesting. Because they don't spin! But that's one for another day, or maybe another thread. Sorry I've got to go. I'll be back tomorrow. Again, apologies for being absent for a while.

No problem..we should be paying you for these lessons.

[ChildInAZoo]

You are saying that we should start using absolutes, but I'm not sure in what sense you are saying this.

No, I'm not saying that. I'm very definitely saying we should USE relativity, we should NOT be trying to use absolutes, because we don't have the tools. I'm just saying that we should just be aware that we are using apparent reality, not REAL reality.

To see what I'm getting at, imagine that today it was announced that phyicists had discovered a new form of 'light' we call Light2.
Light2 is of a totally new nature, and as far as we can tell, the speed of L2 is infinite. It turns out that the universe is bathed in L2, and with new L2 cameras we can now see all the farthest galaxies and stars as they are this very instant, with no detectable delay.
Also, we can now make clocks that use L2, that never vary, keep perfect universal time, and are totally independent of gravity and motion. Also, L2 waves conveniently have markers every centimetre that give us a perfect, invariable ruler.

The big question is :
Which set of tools would you say gives you a true picture of reality?
L2, and L2 clocks and L2 rulers, or the old Light, with finite speed, and with clocks that vary with velocity?.
.

OK, so you are basing your view of what "REAL reality" is on a science fiction scenario ruled out by our best theory of space and time.

[ChildInAZoo]

No problem..we should be paying you for these lessons.

Given some of the very gross inaccuracies in his posts, I think it would be unwise to base your knowledge of physics on what Farsight has written.

[LaMont Cranston]

MrJobby, From what I can tell, you totally misunderstood what I'm writing about. If you're remembering the past or considering possibilities for the future, you are experiencing that in present time. When you make reference to "present orientation," that sounds a lot like woo. Or, if I'm incorrect about this, can you please tell me exactly how considering the past or the future are actually experienced any other time and place than here and now?

Yes, I can make plans for next week or remember last week, but my plans for next week will either happen or they won't, and my memories of the past are as accurate as they are. Nobody is denying that we, as large-brained beings, can remember or contemplate other "thens" and "theres." That's a product of our consciousness; it's part of who we are. There are some philosophies and belief systems that tell you that you do exist completely in the present. If you know of a way to prove that this is not true, I'd love to see that proof.

Among the questions I asked is whether or not the concept of past and future require consciousness. Once again, the state of the cosmos, at this very moment, is what it is. It exists as it exists. Do you think that the concept of past or future orientation exist outside of our consciousness? If your answer is "yes," just how do those things exist?