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Posted
16 minutes ago, swansont said:

It would be an asymmetry, but ultimately a small effect given the numbers usually used. Ballpark is around a part in 10^10 frequency shift, while the speed used has a gamma of 2 or more.

Ok. Cheers.

Posted (edited)

Think of it this way, the Lorentz transforms under constant velocity is time symmetric. under specifically the Minkowskii tensor. Any acceleration including directional change causes rapidity and this is an assymetric time relation that is handled under group via a rotation transformation matrix.

Edited by Mordred
Posted
1 minute ago, Mordred said:

Think of it this way, the Lorentz transforms under constant velocity is time symmetric. Any acceleration including directional change causes rapidity and this is an assymetric time relation that is handled under group via a rotation transformation matrix.

Can you dumb this bit down? Is there a verbal way to describe it?

Posted (edited)

Not without using a little tiny amount of math lol its far easier to show it this way and will be obvious once you see it.

Tranformation equation in positive x direction.

[math]\acute{t}=\gamma(t-\frac{vx}{c^2})[/math]

[math]\acute{x}=\gamma x-vt[/math]

[math]\acute{y}=y[/math]

[math]\acute{z}=z[/math]

now lets reverse the direction by switching the observers

Transformation equation in negative x direction

[math]t=\gamma(\acute{t}+\frac{vx}{c^2}[/math]

[math]x=\gamma x+vt[/math]

the last two are identical Notice that the only thing that has changed is the sign plus or minus depending on the observer? This is a symmetric identity. The only thing that changes is the sign itself in the first two equations.

Now when you do an acceleration this no longer applies

the transforms become

[math] c\acute{t}=ct\cosh\zeta-x\sinh\zeta[/math]

[math]\acute{x}=x\cosh\zeta-ct\sinh\zeta[/math]

although once again the sign will change in the reverse direction on both these you have involved non linear equations which involves trigonometric identities. Thes are assymetric rotations using the trig identities. Instead your undergoing angular momentum rather than linear momentum during the acceleration

 

A non math way to describe it. In the first case if neither observer has any other reference point they are not sure which observer is moving.

In the second case the acceleration change makes it clear which observer is undergoing the change in velocity. Observer A for example can tell he is accelerating or decelerating.

Edited by Mordred
Posted (edited)

OK, finally I can reply again (I was stymied by being a first day member there for a while).

So a clock slows when it moves fast, that's been proven evidently. But I don't see how the behavior of a clock necessarily relates to aging. So StringJunky, a clock goes through time the same as an aging person or an opening flower and because the clock shows a different process at fast speeds then the assumption is that a person aging, or a flower opening, would experience changes in their processes that would coordinate with the changes in the clock? I don't get how you make that jump? Where's the logical leap from rate of clock change to rate of aging or rate of flower opening? Can we not age, or can flowers not bloom, independent of the clock rate? 

Outrider you told me "Time is what clocks measure. A clock can be anything that has a rate of change, so an aging person can be a clock."

I don't get that. An aging person, scientifically speaking, is different from a clock. A clock is a fairly precise measuring device, the aging person is not. As I said above, why does the behavior of the clock at high speeds tell you anything about how a person ages relative to that clock's changes at high speed? That's the part that makes little, or no, sense to me. 

Plainly, I don't get why people have conjured that aging happens by clock rate. People age by time, not clock rate. 

So, just because a clock rate changes at speed, I don't see how that has to do with time in regards to aging or blooming.

Edited by Estranged
Posted (edited)

The clocks are simply a measurement tool. All processes are affected by time dilation. This includes aging. All forms of interactions between particles. 

 Time is literally variable. It takes awhile to wrap your head around this. It is fairly normal as its difficult to fully grasp at first.

Edited by Mordred
Posted
15 minutes ago, Mordred said:

The clocks are simply a measurement tool. All processes are affected by time dilation. This includes aging. All forms of interactions between particles. 

 Time is literally variable. It takes awhile to wrap your head around this. It is fairly normal as its difficult to fully grasp at first.

So the clocks are a measurement tool. That I understand. You're not really explaining. Time is variable. Got it. So what? Time is measured by clock. 

Sorry, didn't mean to seem short

 

So the clocks are a measurement tool, but we base our understanding of time on how they behave, right?

To get our understanding of time by the behavior of clocks which are fickle makes not so much sense to me. 

Posted
12 hours ago, Estranged said:

The clocks going differently doesn't automatically mean there'd be a difference in age if you travel around with that clock or not, right? 

Aging is just another clock. It is equally affected. 

Posted
1 minute ago, Strange said:

Aging is just another clock. It is equally affected. 

But why? Why is it equally explained by the clock? you take that as a given? 

Aging is a different kind of clock, but it's not the same clock measured by minutes and seconds. The clock that makes relativity is not the clock of age.

Posted
7 minutes ago, Estranged said:

But why? Why is it equally explained by the clock? you take that as a given? 

Aging is a different kind of clock, but it's not the same clock measured by minutes and seconds. The clock that makes relativity is not the clock of age.

OK. Every time the clock counts one second, the clock is one second older. How is that different from an aging body. The clock will wear and ultimately stop, just like an aging body.

Posted (edited)

All physical processes that involve rate of change is a form of clock. All physical processes are equally affected by time dilation.  Unfortunately there is no easy way to describe how this occurs. Even if you fully understand all the involved mathematics it is still difficult to fully understand. 

I like to describe it to laymen as a signal propogation delay between all forms of interactions relative to the field locality conditions however that heuristic explanation doesn't encompass the full scope of time dilation. It doesn't particularly describe time dilation due to velocity .

One must examine how each situation is influenced by the mass term "resistance to inertia change" and how mass is influenced by the sum of fields coupling constants and how rest (invariant mass) and relativistic (variant mass) affects the binding energy that contributes to the mass term. 

The latter being involved in the inertial mass.

Part of the problem is in order to understand spacetime itself one must also understand the other fields relating to force. ie electromagnetic, strong and weak force. As well as the Higgs field. They are all involved and all affected.

That is the reality of the challenge to understand relativity. One must also understand how every other field is affected and contributes. In truth the mathematics of GR is only one part of the full story.

Edited by Mordred
Posted
13 minutes ago, Estranged said:

But why? Why is it equally explained by the clock? you take that as a given? 

We know that all physical processes are affected. There is no reason why biochemistry wouldn’t be. 

If every possible method of measuring the time or distance between A and B gives the same result, is there really any difference between saying it is the clock or ruler that has changed rather than it is the time or distance that has changed? Certainly not in science, which deals with what we can measure. 

Posted
1 hour ago, Estranged said:

So the clocks are a measurement tool. That I understand. You're not really explaining. Time is variable. Got it. So what? Time is measured by clock. 

Sorry, didn't mean to seem short

 

So the clocks are a measurement tool, but we base our understanding of time on how they behave, right?

To get our understanding of time by the behavior of clocks which are fickle makes not so much sense to me. 

 

Yes relativity is difficult to get your head around.

I read somewhere (Berkson :-  Fields of Force Routledge) that the main reason folks have difficulty is that we naturally cleave to the idea of an absolute time (and space) and struggle to leave this behind.

So the ghost of the absolute lingers and interferes when we try to understand.

 

Swansont said it all when he said "clocks measure elapsed time", not time. Perhaps you missed this.

 

There are many quantites in Physics that appear in two guises which have the same units but are not quite the same.
In each case one of these purports to be an absolute and the other relative.

Voltage and voltage difference

Gravitational potential and potential difference

Distance and length

Time and time difference or elapsed time

and so on.

 

 

Posted
1 hour ago, studiot said:

Swansont said it all when he said "clocks measure elapsed time", not time. Perhaps you missed this

Are there any real or thought experiments that might make it easier for people to accept that  the clock and the biological  processes cannot be separated and that provided there is no physical separation between the two  the one "maps" to the other  directly?

How to disabuse someone of the absolute(or "detached")  time notion  in an obvious way?

Would "mental prosthetics" if they become (are?)  available achieve that  ? What might be  the  top speed of mental processes if they use electrical currents? 

Posted (edited)
8 hours ago, Mordred said:

Tranformation equation in positive x direction.

t´=γ(tvxc2)

x´=γxvt

y´=y

z´=z

CAN time be regarded as having inertia, and therefore is affected by the acceleration of gravity or acceleration in space? How is the aging process affected in zero gravity?

The equations presented so far do not incorporate both acceleration and deceleration.?

Does a decelerating clock read time at the same speed as an accelerating clock assuming they are changing speed at the same rate?

How does acceleration affect time. How fast does time tick in space in a zero gravity environment, and how fast does it tick in a black hole ?

At the Big bang what was happening with time, in a big black hole crunch what happens with time at the crunch point, in the singularity.

If time measurements could be teleported to other points in the universe via entanglement would that constitute a standard clock, to which other time measurements could be calibrated. What would happen to such readings inside a BH as the readings are accelerated to the crunch point. ?

Happy New Year

Edited by interested
Idiot
Posted
10 minutes ago, interested said:

CAN time be regarded as having inertia, and therefore is affected by the acceleration of gravity or acceleration in space? 

When you ask a question like this, try replacing “time” with “distance” and see if you still want to ask the same question. 

Also, no. 

12 minutes ago, interested said:

The equations presented so far do not incorporate both acceleration and deceleration.?

They’re the same thing, just with different signs. 

22 minutes ago, interested said:

How does acceleration affect time.

Acceleration itself doesn’t, it is difference in speed that is important. 

23 minutes ago, interested said:

At the Big bang what was happening with time, in a big black hole crunch what happens with time at the crunch point, in the singularity.

A singularity means the theory no longer works - a bit like dividing by zero. 

Posted
4 hours ago, Estranged said:

But why? Why is it equally explained by the clock? you take that as a given? 

Aging is a different kind of clock, but it's not the same clock measured by minutes and seconds. The clock that makes relativity is not the clock of age.

If that were the case, then you would be aware of your clock running slow when you were moving faster. But that doesn't make sense because speed is only relative. So the time difference can only be seen from another frame of reference.

Posted (edited)
6 hours ago, StringJunky said:

OK. Every time the clock counts one second, the clock is one second older. How is that different from an aging body. The clock will wear and ultimately stop, just like an aging body.

Man my head hurts. And Happy New Year to all! My New Year resolution is that I aim to go mad until I understand this stuff.

The clock is a mechanical device developed by biological humans who invented the units that the clock measures. So that's how clocks are different from an aging body. A clock can't make things age and it might not be perfect at measuring age either. An aging body ages whether there's a clock or not. Changes in a clock's rate do not mean there's changes in other things that are effected by time.

I get that clocks are supposed to measure time, and they do, but couldn't clocks be potentially bad at measuring time under certain conditions? Like when they go really fast? Maybe, while the clock changes under those conditions, other measures of time, like aging, do not. Aging and clocks are different kinds of time measures, right? This seems not only logically plausible to me, but likely. 

I hope I'm making some kind of sense. I really appreciate everyone trying to answer me. 

 

1 hour ago, Strange said:

If that were the case, then you would be aware of your clock running slow when you were moving faster. But that doesn't make sense because speed is only relative. So the time difference can only be seen from another frame of reference.

Why would you be aware if the difference is so minuscule? Maybe I'm not sure what you're saying. 

5 hours ago, studiot said:

 

Yes relativity is difficult to get your head around.

I read somewhere (Berkson :-  Fields of Force Routledge) that the main reason folks have difficulty is that we naturally cleave to the idea of an absolute time (and space) and struggle to leave this behind.

So the ghost of the absolute lingers and interferes when we try to understand.

 

Swansont said it all when he said "clocks measure elapsed time", not time. Perhaps you missed this.

 

There are many quantites in Physics that appear in two guises which have the same units but are not quite the same.
In each case one of these purports to be an absolute and the other relative.

Voltage and voltage difference

Gravitational potential and potential difference

Distance and length

Time and time difference or elapsed time

and so on.

 

 

I don't really think I'm saying anything differently from you, in essence. Especially the part where you say "there are many quantities in Physics that appear in two guises which have the same units but are not quite the same." That's what I'm saying about aging vs clock rates, that they may appear to have the same units, but they may not be quite the same. It seems rather arrogant to me to me that our biological humanity could presume to invent a mechanical device that could measure aging with atomic accuracy. 

Edited by Estranged
Posted

 Don't get stuck at looking for clock errors. This will lead you down garden paths.

 There are other processes not involving mechanical or atomic clocks that cannot be explained without time dilation. A common example being muon decay, muons have too short a mean lifetime to be able to pass through the Earths atmosphere. Yet they strike the Earths surface, thanks to time dilation. 

While not directly related to time dilation, it does affect the mass term, we can generate particles at an LHC which has a higher rest mass than the combined rest mass of the two colliding particles.

Then on top of the gravitational redshift demonstrates the effect of time dilation on signals recieved. Which is another piece of evidence. Another being GPS satelites if we didn't account for time dilation they wouldn't be accurate.

The list of tests is quite huge and far more encompassing than what could be explained as clock errors.

 

Posted
11 minutes ago, Estranged said:

Man my head hurts. And Happy New Year to all! My New Year resolution is that I aim to go mad until I understand this stuff.

The clock is a mechanical device developed by biological humans who invented the units that the clock measures. So that's how clocks are different from an aging body. A clock can't make things age and it might not be perfect at measuring age either. An aging body ages whether there's a clock or not. Changes in a clock's rate do not mean there's changes in other things that are effected by time.

I get that clocks are supposed to measure time, and they do, but couldn't clocks be potentially bad at measuring time under certain conditions? Like when they go really fast? Maybe, while the clock changes under those conditions, other measures of time, like aging, do not. Aging and clocks are different kinds of time measures, right? This seems not only logically plausible to me, but likely. 

I hope I'm making some kind of sense. I really appreciate everyone trying to answer me. 

I'm only a novice like you but a few years up the road. All I can say is just accept what you've been told about this and eventually you'll get used to it. You are trying to absorb a lot of things at once and not just about relativity itself but the terminology and the way scientists think. Eventually, it will slowly come together. When you see someone like Mordred writing the way he does, that's more than twenty years of thinking about science and methodically unpicking what it means. You won't get your head around relativity in a few posts.

Posted
8 minutes ago, Mordred said:

 Don't get stuck at looking for clock errors. This will lead you down garden paths.

 There are other processes not involving mechanical or atomic clocks that cannot be explained without time dilation. A common example being muon decay, muons have too short a mean lifetime to be able to pass through the Earths atmosphere. Yet they strike the Earths surface, thanks to time dilation. 

While not directly related to time dilation, it does affect the mass term, we can generate particles at an LHC which has a higher rest mass than the combined rest mass of the two colliding particles.

Then on top of the gravitational redshift demonstrates the effect of time dilation on signals recieved. Which is another piece of evidence. Another being GPS satelites if we didn't account for time dilation they wouldn't be accurate.

The list of tests is quite huge and far more encompassing than what could be explained as clock errors.

 

So the whole thing about the twins when one leaves Earth really fast and comes back really fast and the one who stayed on Earth is younger than the one who left...that's wrong? I'm talking specifically about age vs. clock rate, and how measures of clock rate haven't been shown to define aging. I'm just trying to start at a real low level, I can't think of any other way to build knowledge. 

Posted
14 minutes ago, StringJunky said:

I'm only a novice like you but a few years up the road. All I can say is just accept what you've been told about this and eventually you'll get used to it. You are trying to absorb a lot of things at once and not just about relativity itself but the terminology and the way scientists think. Eventually, it will slowly come together. When you see someone like Mordred writing the way he does, that's more than twenty years of thinking about science and methodically unpicking what it means. You won't get your head around relativity in a few posts.

Now my age is showing lol

Posted
15 minutes ago, StringJunky said:

All I can say is just accept what you've been told about this and eventually you'll get used to it. You are trying to absorb a lot of things at once and not just about relativity itself but the terminology and the way scientists think. Eventually, it will slowly come together. When you see someone like Mordred writing the way he does, that's more than twenty years of thinking about science and methodically unpicking what it means. You won't get your head around relativity in a few posts.

OK, to be fair, I've been trying to absorb this for the better part of a decade. My newness to it is certainly relative. It's those things that everyone says "just accept" that I don't get. When someone says "just accept it because it's accepted" that's when I become really interested. :)

Posted (edited)
4 minutes ago, Estranged said:

So the whole thing about the twins when one leaves Earth really fast and comes back really fast and the one who stayed on Earth is younger than the one who left...that's wrong? I'm talking specifically about age vs. clock rate, and how measures of clock rate haven't been shown to define aging. I'm just trying to start at a real low level, I can't think of any other way to build knowledge. 

The aging is one aspect of it, aging can be considered another form of clock with similarities to radioactive decay. All particle processes that occur in a biological body is affected. 

To understand this aspect you need to first grip a proper understanding of mass. In particular how mass of said body varies due to motion and how this affects the coupling constants

Edited by Mordred

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