# Simple explanation for time dilation

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In gravitational time dilation all observers agree.

No they don't.

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You are an analogy? As far as I know you are not the Einstein Field Equations or an equation derived from them.

!

Moderator Note

OK, we're up to four pages now, and I still don't see much rigor. Lots of denial and hand-waving, lots of basic misunderstandings (I could list them, but a re-read is probably a good idea), lots of sound explanations rejected over incredulity. Very bad form for scientific inquiries.

Last warning. This thread is in danger of being closed. Please answer all the questions put to you (a great way to learn), and don't just cherry-pick the ones you like. This seems to lead you to rejecting everyone's explanations.

More rigor, please. No response to this note is necessary.

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If three cars took different routes through space, you would not be surprised when their odometers recorded different distances. If they take different routes through space-time then their clocks will show a different elapsed time as well. Shocker.

The clocks travel in spacetime with the speed c, right?

"The photon" in a light clock travel with the same speed, c, right?

So, the distance traveled in space-time by the light clock is equal with the distance covered by "the photon" between mirrors in the same light clock, because there is only one time interval for that clock. In H.K. experiment, all the observers agreed with the time intervals measured by the clocks. After the clocks were reunited and the stop button pressed simultaneously, there is no way to see another end result from another frame. Agree?

So, time dilation in light clocks is related to the distance travelled by the photons between mirrors.

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The clocks travel in spacetime with the speed c, right?

What does that mean? We know the clocks all travel at different speeds.

In H.K. experiment, all the observers agreed with the time intervals measured by the clocks. After the clocks were reunited and the stop button pressed simultaneously, there is no way to see another end result from another frame. Agree?

I'm afraid I don't know what that means. It is too vague. Does "all the observers agreed with the time intervals measured by the clocks" just mean that they all agreed that the clocks read different elapsed times? Well, obviously. It would be rather strange if they all looked at the same clock and thought it said different things.

Or are you saying that they all though that the three clocks ran at the same speed? That is obviously not true.

I think you need to be a bit clearer about what you are trying to say. I recommend mathematics for this purpose.

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I don't agree that spacetime is a substance.

I live in spacetime, so for me it's real enough. You think it isn't?

I can move left-right, forward-backward, up-down, so at least space is real.

Can you hand me a chunk of spacetime?

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Last warning. This thread is in danger of being closed. Please answer all the questions put to you (a great way to learn), and don't just cherry-pick the ones you like. This seems to lead you to rejecting everyone's explanations.

You think that Einstein Field Equations are a simple explanation for time dilation?

Please don't close this discussion until we reach to a simple explanation. I hope you don't agree with the statement: "Everything that can be Invented has been Invented".

I wrote in the beginning:

Please keep in mind, first, that I totally agree with relativity's results/predictions and second, that I don't expect from you the mathematical models and equations used to make the predictions, I want simple answers to the questions above, the physical explanation of time dilation.

This is not because I reject mathematics. It is because I have an idea on how a physical explanation should be and I want to lead you to it. That's the reason for "cherry-pick"-ing.

On the other hand, I noticed the same "cherry-pick"-ing from the others. They lead me again and again towards mathematics and refuse to cooperate with me. There are a lot of questions I wrote still unanswered ...

Last but not least, keep in mind that Einstein wrote his relativity more than 100 years ago. Since then we learned a lot about the Universe. To name a few: Higgs field, dark matter, dark energy. Back in his time, an intuitive relativity was not possible, but now it is. Just folow my lead and you will understand it.

Another thing, English is not my first language, so it's harder for me to make myself clear. Also my computers are very old and slow ... Please have patience.

I am pretty close to get where I want, so, again, please don't close this thread until we get to a simple explanation for time dilation in matter (atoms, molecules).

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Please don't close this discussion until we reach to a simple explanation.

You haven't managed it after 5 pages. How much more do you need?

Also, if your explanation does not involve mathematics then it is of no value.

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Oh boy this thread is going in circles. DanP you admit you don't understand the math, so I have to ask how can you claim to have a better understanding of GR than those that do understand the math????

Let's look at an example I posted for another poster that figured he could fix GR...

Lorentz transformation.

First two postulates.

1) the results of movement in different frames must be identical

2) light travels by a constant speed c in a vacuum in all frames.

Consider 2 linear axes x (moving with constant velocity and $\acute{x}$ (at rest) with x moving in constant velocity v in the positive $\acute{x}$ direction.

Time increments measured as a coordinate as dt and $d\acute{t}$ using two identical clocks. Neither $dt,d\acute{t}$ or $dx,d\acute{x}$ are invariant. They do not obey postulate 1.

A linear transformation between primed and unprimed coordinates above

in space time ds between two events is

$ds^2=c^2t^2=c^2dt-dx^2=c^2\acute{t}^2-d\acute{x}^2$

Invoking speed of light postulate 2.

$d\acute{x}=\gamma(dx-vdt), cd\acute{t}=\gamma cdt-\frac{dx}{c}$

Where $\gamma=\frac{1}{\sqrt{1-(\frac{v}{c})^2}}$

Time dilation

dt=proper time ds=line element

since $d\acute{t}^2=dt^2$ is invariant.

an observer at rest records consecutive clock ticks seperated by space time interval $dt=d\acute{t}$ she receives clock ticks from the x direction separated by the time interval dt and the space interval dx=vdt.

$dt=d\acute{t}^2=\sqrt{dt^2-\frac{dx^2}{c^2}}=\sqrt{1-(\frac{v}{c})^2}dt$

so the two inertial coordinate systems are related by the lorentz transformation

$dt=\frac{d\acute{t}}{\sqrt{1-(\frac{v}{c})^2}}=\gamma d\acute{t}$

So the time interval dt is longer than interval $d\acute{t}$

If your not using Lorentz then you need to define the coordinate transformation rules.

Here is relativity of simultaneaty coordinate transformation in Lorentz.

$\acute{t}=\frac{t-vx/c^2}{\sqrt{1-v^2/c^2}}$

$\acute{x}=\frac{x-vt}{\sqrt{1-v^2/c^2}}$

$\acute{y}=y$

$\acute{z}=z$

Note the mention of frames in postulate one. This means more accurately that both Alice and Bob are correct in their measurements and there is no preferred frame of reference.

Now why did I include length contraction? The answer is... I'll leave to you (hint postulate 2)

If you truly want to master SR and GR stop learning via pop media. I'll provide two useful textbooks. The first is written by a professor who has been on forums for years so he's used to common misconceptions such as those you've shown. Deals with SR primarily (best to start here)

http://www.lightandmatter.com/sr/

The second is specifically GR the math level is considerably higher. The article specifically discusses many errors due to artifacts in coordinate misunderstandings in GR.

http://www.blau.itp.unibe.ch/newlecturesGR.pdf"Lecture Notes on General Relativity" Matthias Blau

Trying to argue against GR without knowledge of the math is like trying to kill a T rex with a spitball

To yell once again lol FRAMES MATTER

Now test question.

Out of your several threads which experiment did you mention does these mathematics best describe?

(Not that they aren't applicable to others by best describe I mean most commonly shown to model)

The math is here about as simple as relativity gets. I also included two textbook links. The first link is extremely basic math Edited by Mordred
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I'm afraid I don't know what that means. It is too vague. Does "all the observers agreed with the time intervals measured by the clocks" just mean that they all agreed that the clocks read different elapsed times? ...

I think you need to be a bit clearer about what you are trying to say.

Ok, let's try again with the Hafele-Keating (H-K) experiment:

We have 3 atomic clocks on a table, perfectly synchronized. We take a photo with their displays (the START moment) and then fly one around the globe westwards and another eastwards. When reunited on the same table, we take another photo with their displays (the STOP moment).

Now, what we see in the STOP photo? We see that the clocks are no longer synchronic. There are differences between them, in nanoseconds, exactly how relativity predicted. If the clocks remain there, on the same table, they will keep having these differences as long as they function.

So, what I'm trying to say is that any observer from any frame will agree with those differences. It is impossible to disagree with the end result recorded on the photo.

Do you understand/agree until here?

@Mordred

Last but not least, keep in mind that Einstein wrote his relativity more than 100 years ago. Since then we learned a lot about the Universe. To name a few: Higgs field, dark matter, dark energy. Back in his time, an intuitive relativity was not possible, but now it is. Just folow my lead and you will understand it.

Edited by DanMP
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DanP relativity didn't stop with Einstein. The equations today are far more complex than his time.

Perhaps if you actually read the material provided you might just learn something

Edited by Mordred
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Another thing, English is not my first language, so it's harder for me to make myself clear. Also my computers are very old and slow ... Please have patience.

I am pretty close to get where I want, so, again, please don't close this thread until we get to a simple explanation for time dilation in matter (atoms, molecules).

!

Moderator Note

It's clear you aren't reading what's being offered to you. As has been mentioned, you're no closer to seeing your mistakes after 5 pages than you were in the beginning. All I see are excuses about computers and language, and no supportive evidence for your explanation. I fail to see how you're any closer, considering you're still crying "I'm right, and everyone else is wrong". And the call for members to "cooperate with you" by NOT bringing up math is ludicrous.

I'll check back at the end of the day. Support and progress, the thread stays open. Otherwise, we've stretched the rules for you quite a bit, but there are limits. The thread will be closed if you can't show why your simple explanation is better than current ones.

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Ok, let's try again with the Hafele-Keating (H-K) experiment:

We have 3 atomic clocks on a table, perfectly synchronized. We take a photo with their displays (the START moment) and then fly one around the globe westwards and another eastwards. When reunited on the same table, we take another photo with their displays (the STOP moment).

Now, what we see in the STOP photo? We see that the clocks are no longer synchronic. There are differences between them, in nanoseconds, exactly how relativity predicted. If the clocks remain there, on the same table, they will keep having these differences as long as they function.

So, what I'm trying to say is that any observer from any frame will agree with those differences. It is impossible to disagree with the end result recorded on the photo.

Do you understand/agree until here?

the length contraction formulas I provided you work for particle to particle interactions as well as an observer. I also referred you to an example in Moun decay rates.

Time dilation also affect moving particles and their decay rates this should provide the clue you need.

https://en.m.wikipedia.org/wiki/Time_dilation_of_moving_particles

http://www.einstein-online.info/elementary/specialRT/relativity_space_time

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Ok, let's try again with the Hafele-Keating (H-K) experiment:

We have 3 atomic clocks on a table, perfectly synchronized. We take a photo with their displays (the START moment) and then fly one around the globe westwards and another eastwards. When reunited on the same table, we take another photo with their displays (the STOP moment).

Now, what we see in the STOP photo? We see that the clocks are no longer synchronic. There are differences between them, in nanoseconds, exactly how relativity predicted. If the clocks remain there, on the same table, they will keep having these differences as long as they function.

So, what I'm trying to say is that any observer from any frame will agree with those differences. It is impossible to disagree with the end result recorded on the photo.

The photo is a measurement within the rest frame of the clocks and yes - all observers would view the photo the same. BUT and it is a humongous BUT; if rather than take a single photo (which is a purely local measurement and thus frames of observers are irrelevant as the measure is taken locally) you have the three clocks in a row aligned north south - the man in the lab notices that they are not synchronised (datum, datum + x, and datum - y) when he takes his snap, the man in the spaceship doing 0.5c heading north will not agree with the offsets of the clocks and will take a photo with a different result, so will the man in the train doing 0.25 c southwards. That difference of datum, +x and -y is only measureable from the rest frame - the only photo with those offsets. All the photos will be different and the offsets will all vary - however the rest frame result is calculable from all frames because we, the man in the spaceship and in the train all know how to boost and transform frames of reference.

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The photo is a measurement within the rest frame of the clocks and yes - all observers would view the photo the same. BUT and it is a humongous BUT...

Ok than, let the STOP moment be a real stop, meaning that the man in the lab stops the clocks by pushing one button, "freezing" the displays.

So, between START and STOP, 3 photons, one for each light clock, flew between mirrors with the same speed c, same time (different observers will not agree about the value, but will agree that the time was the same, between the START and STOP, for all clocks/photons) but completed different number of cycles. That can be explained by longer routes/paths taken by each photon (the "saw teeth" for kinematic time dilation and spacetime warping for gravitational time dilation). And this time, all the observers agree with the differences in path between the 3 clocks.

We can mimic the result of the experiment by building light clocks with different distances between mirrors and keeping all on the same table, near the first one. We can adjust the distances until we get exact the same result.

Or, we can keep the distance between mirrors identical and "adjust" (it is a thought experiment) the speed of 2 photons, until we get the same result.

Now, consider that one mirror of a light clock is the nucleus of an atom and the other one electron in its cloud, and that electromagnetic force is considered to be transmitted through virtual particles travelling exactly like photons (same speed/path). In my opinion the change in path observed in light-clock photons translates in similar changes in paths for force transmitting particles between different elements of the atom, and this is what cause the time dilation in atoms, not the mathematics, not the frames.

In order to verify this assumption, just calculate what a change in electromagnetic interraction speed does in an atom used in a real, atomic, clock. See how energy levels change ... an how the frequency you use to measure time (in atomic clocks) changes.

I wrote this in a hurry, because I'm busy and forced by the moderator to do it now or never, so I'm sure you will have a great laught, but do the maths first and that laugh.

This is not my "pet theory"! Just an idea from it, similar with Ryan's rewarded idea. My theory is much more than that.

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In order to verify this assumption, just calculate what a change in electromagnetic interraction speed does in an atom used in a real, atomic, clock. See how energy levels change ... an how the frequency you use to measure time (in atomic clocks) changes.

Tell us what you get, and more importantly, how you calculated this. The only way I know how to determine the result is with relativity.

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The problem, Dan, is that you make a statement, get challenged on it, and rather than responding come up with a different statement.

1. You seem to flip without hesitation between actual atomic clocks (which work on a hyperfine transition - a spin flip of a single electron) and purely hypothetical photon light clocks.

2. No matter how you phrase it - there can be no absolute simultaneity between mutually moving frames.

3. Your argument on the speed of electromagnetic interaction is in need of some work

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Tell us what you get, and more importantly, how you calculated this. The only way I know how to determine the result is with relativity.

!

Moderator Note

This seems like a good benchmark test. Answer this and it looks like we can make some actual progress in this discussion.

I hope you can look back through the thread and see how much time was wasted because you haven't been able to give the members involved enough information to move forward. Can you now verify your own assumption?

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The photo is a measurement within the rest frame of the clocks and yes - all observers would view the photo the same. BUT and it is a humongous BUT; if rather than take a single photo (which is a purely local measurement and thus frames of observers are irrelevant as the measure is taken locally) you have the three clocks in a row aligned north south - the man in the lab notices that they are not synchronised (datum, datum + x, and datum - y) when he takes his snap, the man in the spaceship doing 0.5c heading north will not agree with the offsets of the clocks and will take a photo with a different result, so will the man in the train doing 0.25 c southwards. That difference of datum, +x and -y is only measureable from the rest frame - the only photo with those offsets. All the photos will be different and the offsets will all vary - however the rest frame result is calculable from all frames because we, the man in the spaceship and in the train all know how to boost and transform frames of reference.

I thought again about it and realized that the START photo/moment is seen also differently from your spaceship/train and the differences you mention are not only very small but also cancelled out from START to STOP, leaving the differences between the H-K clocks the same for all inertial frame/observers. Am I right?

Tell us what you get, and more importantly, how you calculated this. The only way I know how to determine the result is with relativity.

I said I want to lead you towards a simple/physical explanation for time dilation in matter, not that I will give you a complete answer. For me it's important here just to see if you are interested to pursue this idea, if you find it as interesting as the people that awarded Ryan's idea did. Only if you are, I will post my "pet theory".

You have to admit that something must happen in atoms when force transmitting particles appear to move slower. The way to determine exactly what happens is by using quantum physics, not relativity, because QPh is the theory that describe the atom. Change the speed of light/interactions from c to a fraction of c, Fc, and see what happens with the energy levels in atoms.

If energy levels in atoms change, than the interval for the "hyperfine transition" also changes, meaning that the frequency you measure in the atomic clock changes ... Calculate this and you will have the time dilation. Then apply it to see how this "modified" atomic clock would see the speed of light. I'm confident that you will get again c, not Fc.

In my theory I used an over-simplified, almost naive, but logical approach and I obtained the fact that the speed of light in meters per second is always c, even it appears to change. Al our instruments are made of atoms, and they compensate any apparent change in light/interaction speed. This finding is in agreement with Einstein's relativity, so the maths may remain the same. Only the understanding changes (and much more than that, as you may see in my theory if you give me a pozitive feedback).

Edited by DanMP
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I said I want to lead you towards a simple/physical explanation for time dilation in matter, not that I will give you a complete answer. For me it's important here just to see if you are interested to pursue this idea, if you find it as interesting as the people that awarded Ryan's idea did. Only if you are, I will post my "pet theory".

My interest is purely academic, i.e. to poke holes in it, because the chances you have anything valid is essentially nil.

What I'm not interested in are repeated "teasers" about posting it. If you aren't going to show us the frog in your pocket, the least you can do is shut up about it.

You have to admit that something must happen in atoms when force transmitting particles appear to move slower.

Why do I have to admit this? There's no science behind the assertion. It is, in fact, the opposite of what science has concluded (the laws of physics remain the same in each frame of reference, and there are no preferred frames)

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... the chances you have anything valid is essentially nil.

Based on what? You know how much of the Universe "became" "dark" 100 years after Einstein's relativity? Considering this, you shouldn't be so sure. We all should be humble and open minded, not over-confident in old theories ...

And a new theory must agree with the old one findings. Check my edited message above to see that mine does ...

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!

Moderator Note

OK, this is ridiculous. You have enough people telling you they're interested in hearing your theory, not peripheral dribs and drabs that can't be answered meaningfully without the fuller picture.

You need to decide if you want to do this the right way, and let those you came here to listen to give you some meaningful dialogue about this idea you have. If you don't want to share it, then don't bring it up again. If you want to share it, you should open a full thread in Speculations about it, and be as rigorous as you can.

You need to realize how many people come here with ideas they can't support. Most end up being wrong, by a vast majority, but that's not really the point. The point is treating an hypothesis the right way, so you can more easily see where you're right, and where you're wrong. This hasn't been done so far with this "teaser" approach. It's actually a disservice to you, and all who are participating.

So you decide if you want to step into the saddle or just keep walking this horse to no purpose. This thread is closed.

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Based on what?

Most ideas are wrong, and lots of smart people have tried. That gives you pretty long odds.

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