Comparing Tick rates of clocks across Frames

[james fairclear]

TL;DR Summary

Comparing Tick rates of clocks across Frames

Comparing Tick rates of clocks across Frames

Clock A and Clock B and clock C are stationary with each other in the same location and synchronised.

Clock A is accelerated and its tick rate is found to have changed from what it was prior to acceleration.

We might then enquire: Measured by whom? Some frames will say it has increased, others will say it has decreased. It depends whether the clock's speed decreased or increased in the frame of interest.

The tick rate of a clock is a relative quantity.

We judge the relative tick rate of clock A by comparing the amount of time it has recorded with the amount of time recorded by other clocks B and C with which it was previously synchronised.

The indicated time on each of the respective clocks is continuously broadcast by radio waves for observation during the experiment and also recorded electronically for observation at the end of the experiment. A sample of the continuous recordings might for example be as follows:

Indicated time on Clocks
A	B	C
0​	0​	0​
15​	15​	15​
30​	30​	30​
45​	45​	45​
60​	60​	60​
Clock A Accelerated
70​	75​	75​
78​	90​	90​
84​	105​	105​
88​	120​	120​
90​	135​	135​

In this example we see that clock A starts to progressively record less time than it did prior to the acceleration. The reverse can also be the case but it must be one or the other.

The pattern of readings from an accelerated clock indicates whether the tick rate increases or decreases subsequent to the acceleration and on inspection of the recorded data this pattern must de facto be agreed upon by all non-accelerating observers.

 

[PeroK]

Imagine you are in an aeroplane travelling at 200m/s, relative to the ground. On the ground are two cars, both at rest relative to the ground. Hence both moving at 200m/s relative to the plane.

The cars accelerate to 20m/s in opposite directions. To an observer at rest relative to the ground both cars have speeded up to 20m/s.

Relative to the aeroplane, however, one car has speeded up to 220m/s and other has slowed down to 180m/s. Assuming all motion is along the same line.

Now, it cannot be de facto agreed by all observers which car has speeded up and which car has slowed down. This is frame dependent. A second aeroplane, travelling in the opposite direction, would measure the speeding up and slowing down to apply to the opposite cars.

Your claims, therefore, about relative speed are not valid - even before we consider relativity.

 

[Dale]

We judge the relative tick rate of clock A by comparing the amount of time it has recorded with the amount of time recorded by other clocks B and C with which it was previously synchronised.

Usually we judge the relative tick rate of clock A by comparing the amount of time it has recorded with the amount of coordinate time recorded in a given reference frame. In other words if $\tau_A$ is the proper time on clock A and $\tau_B$ is the proper time on clock B and $t$ is the coordinate time for some specified reference frame. Then the relative tick rate of A is $d\tau_A/dt$ and the relative tick rate of B is $d\tau_B/dt$

A B C
0 0 0
15 10 4
30 15 8
45 20 12
60 25 16
Clock A Accelerated
50 30 20
42 35 24
36 40 28
32 45 32
28 50 36

Clocks slow down, they don't run backwards. It looks like you are just making these up, and you are not making them up in a manner that is consistent with physics.

The pattern of readings from an accelerated clock indicates whether the tick rate increases or decreases subsequent to the acceleration and on inspection of the recorded data this pattern must de facto be agreed upon by all non-accelerating observers.

Again, it is the comparison between a clock and the coordinate time that determines the tick rate. Different non-accelerating observers will use different coordinate time so, no, the pattern is not agreed upon by all non-accelerating observers.

 

[Ibix]

Why are clocks B and C recording different times? They're at rest with respect to each other and synchronised aren't they?

You need to use actual numbers, not made-up ones that you can have do anything whether it makes sense or not.

 

[james fairclear]

Usually we judge the relative tick rate of clock A by comparing the amount of time it has recorded with the amount of coordinate time recorded in a given reference frame. In other words if $\tau_A$ is the proper time on clock A and $\tau_B$ is the proper time on clock B and $t$ is the coordinate time for some specified reference frame. Then the relative tick rate of A is $d\tau_A/dt$ and the relative tick rate of B is $d\tau_B/dt$

Clocks slow down, they don't run backwards. It looks like you are just making these up, and you are not making them up in a manner that is consistent with physics.

Again, it is the comparison between a clock and the coordinate time that determines the tick rate. Different non-accelerating observers will use different coordinate time so, no, the pattern is not agreed upon by all non-accelerating observers.

"Clocks slow down, they don't run backwards. It looks like you are just making these up, and you are not making them up in a manner that is consistent with physics."

There are 3 columns for Clock A , B and C. The indicated times for each clock are set out vertically below each heading . They definitely run forwards!

 

[Ibix]

They definitely run forwards!

Clock A Accelerated
50 30 20
42 35 24

42 is after 50 according to you? Or is 35 before 30 and 24 before 20?

 

[james fairclear]

Imagine you are in an aeroplane travelling at 200m/s, relative to the ground. On the ground are two cars, both at rest relative to the ground. Hence both moving at 200m/s relative to the plane.

The cars accelerate to 20m/s in opposite directions. To an observer at rest relative to the ground both cars have speeded up to 20m/s.

Relative to the aeroplane, however, one car has speeded up to 220m/s and other has slowed down to 180m/s. Assuming all motion is along the same line.

Now, it cannot be de facto agreed by all observers which car has speeded up and which car has slowed down. This is frame dependent. A second aeroplane, travelling in the opposite direction, would measure the speeding up and slowing down to apply to the opposite cars.

Your claims, therefore, about relative speed are not valid - even before we consider relativity.

The recorded indicated times on each clock are a matter of fact.

 

[Ibix]

The recorded indicated times on each clock are a matter of fact.

...but cannot match the numbers you are presenting as "facts".

 

[FactChecker]

Why are clocks B and C recording different times? They're at rest with respect to each other and synchronised aren't they?

Good point. This scenario is fatally flawed.

You need to use actual numbers, not made-up ones that you can have do anything whether it makes sense or not.

I don't know if the numbers have to be accurate as long as he can make a point with them. It depends on what point he is trying to make. I don't see what point he is trying to make. That might be because his scenario is so flawed and he never says what the point is.

 

[james fairclear]

42 is after 50 according to you? Or is 35 before 30 and 24 before 20?

Apologies I made an error copying and pasting from spreadsheet and have now corrected it!

 

[Ibix]

Apologies I made an error copying and pasting from spreadsheet and have now corrected it!

But still the question stands: why are B and C not showing the same time?

 

[Dale]

There are 3 columns for Clock A , B and C. The indicated times for each clock are set out vertically below each heading . They definitely run forwards!

Not clock A after acceleration

The recorded indicated times on each clock are a matter of fact.

No, they are not. They are made up and they are made up in a way that is inconsistent with known facts.

 

[PeroK]

The recorded indicated times on each clock are a matter of fact.

Every clock is always instantaneously at rest in some inertial reference frame. Therefore, there is always an inertial reference frame in which is it not measured to be ticking slowly - regardless of its past acceleration profile.

 

[Ibix]

I don't know if the numbers have to be accurate as long as he can make a point with them.

Well, at some point he's going to have to transform to some other frame to prove his (incorrect) claim that the clock rate decreases in all frames. He's going to need $x$ positions at that time and those are going to need to match up with the velocities implied by his tick rate numbers.

 

[james fairclear]

Imagine you are in an aeroplane travelling at 200m/s, relative to the ground. On the ground are two cars, both at rest relative to the ground. Hence both moving at 200m/s relative to the plane.

The cars accelerate to 20m/s in opposite directions. To an observer at rest relative to the ground both cars have speeded up to 20m/s.

Relative to the aeroplane, however, one car has speeded up to 220m/s and other has slowed down to 180m/s. Assuming all motion is along the same line.

Now, it cannot be de facto agreed by all observers which car has speeded up and which car has slowed down. This is frame dependent. A second aeroplane, travelling in the opposite direction, would measure the speeding up and slowing down to apply to the opposite cars.

Your claims, therefore, about relative speed are not valid - even before we consider relativity.

In your experiment if each vehicle carries a clock then the readouts of the indicated clock times will indicate the relative acceleration patterns of each vehicle.

 

[Ibix]

In your experiment if each vehicle carries a clock then the readouts of the indicated clock times will indicate the relative acceleration patterns of each vehicle.

...when you compare them to some other clock. But then we're back to the (unattributed) quote from me in your OP:

Measured by whom? Some frames will say it has increased, others will say it has decreased. It depends whether the clock's speed decreased or increased in the frame of interest.

 

[PeroK]

In your experiment if each vehicle carries a clock then the readouts of the indicated clock times will indicate the relative acceleration patterns of each vehicle.

Acceleration does not cause time dilation - that's the clock hypothesis:

https://en.wikipedia.org/wiki/Time_dilation#Clock_hypothesis

 

[james fairclear]

Well, at some point he's going to have to transform to some other frame to prove his (incorrect) claim that the clock rate decreases in all frames. He's going to need $x$ positions at that time and those are going to need to match up with the velocities implied by his tick rate numbers.

The readings from the clock are continuously recorded during the experiment in the frame of each clock. The recorded numbers are a matter of fact for any observer to inspect.

The recorded numbers aren't tick rates they are continuous readings from the clock.

 

[PeroK]

The readings from the clock are continuously recorded during the experiment in the frame of each clock. The recorded numbers are a matter of fact for any observer to inspect.

Yes, but regardless of acceleration, the readouts for each clock will be 1, 2, 3, 4 ... The question is how do you collate those readouts from multiple clocks, given they are all moving with different velocities.

 

[james fairclear]

...but cannot match the numbers you are presenting as "facts".

The numbers given are just an example to show that the readings from Clock A vary against those from clock B and C which is factually correct.

 

[Ibix]

The recorded numbers are a matter of fact for any observer to inspect.

Sure. But what are you comparing each list of numbers to?

Look, here's the clock readings on my watch:
16.47.01
16.47.02
16.47.03
16.47.04
Is it running fast or slow?

 

[Vanadium 50]

If the OP back-edits messages in response to detected errors, this thread will just become an inconsistent mess: people responding to messages that are no longer what is showing.

Time to start over?

 

[PeterDonis]

Thread closed for moderation.

 

[PeterDonis]

After moderator review, the thread will remain closed.

@james fairclear, you have had a number of threads now (one of them back in 2021), all based on the same wrong claims. Any further threads from you based on those same wrong claims will be warned and deleted. Please take the time to learn how relativity actually works.