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Let's say for illustration, the connecting rod is 3 light seconds long and the following parameters apply:

The COM observer will see a clock :

on the faster rotating M1, ticking at rate of $\sqrt{1-0.8^2} = 0.6$ ticks/second

on the slower rotating M2, ticking at rate of $\sqrt{1-0.4^2} \approx 0.9165$ ticks/second due to time dilation.

M1 does not see her own clock as time dilated and as far as she is concerned, her clock is ticking at a rate of 1 tick/second. Instead she sees signals coming from M2 as coming at a rate of 0.9165/0.6 $\approx$ 1.5275 ticks/second.

By similar reasoning, M2 sees his clock ticking at a rate of 1 tick per second and sees signals coming from M1 at a rate of 0.8/0.9165 $\approx$ 0.6546 ticks/second.

While all 3 observers measure different rates, they all agree that the clock on M1 is ticking at $\approx 0.6546$ of the rate of the clock on M2.
M1 sees M2's clock ticking faster than his own. M2 sees M1's clock as ticking slower than his own. The central COM observer also sees M1 ticking slower than M2.

It might seem counter intuitive to have such a clear result that all observer's agree on, because in relativity sometimes it is difficult to even define which object is faster and usually everything is symmetrical, but in this case rotation (and proper acceleration) is involved and measurements are absolute.

It might also seem slightly odd that M1 sees M2's clock ticking at a rate that is greater than unity, which seems counter to the idea of time dilation.

The reason is that M1 and M2 are not inertial observers but are experiencing proper acceleration and by the equivalence principle they see things as if they are in a gravitational field. M1 has the greater proper acceleration due to traveling the fastest on a longer radius, so M1 feels like she is lower in a gravitational field and sees signals coming from M2 higher up as blue shifted and sped up. Similarly, M2 with the lesser proper acceleration feels like he is higher up in a gravitational field and sees signals coming from M1 lower down as gravitational time dilated and red shifted.

Here is another simple example of non reciprocal time dilation. Consider the Einstein carousel thought experiment. The inertial clock at the centre ticks at a rate of 1 tick per second. The clock on the perimeter ticks at a slower rate due to velocity time dilation. The observer on the perimeter of the carousel that experiences proper acceleration is non inertial and considers the clock at the centre to be ticking faster than his own clock.

Let's say for illustration, the connecting rod is 3 light seconds long and the following parameters apply:

The COM observer will see a clock :

on the faster rotating M1, ticking at rate of $\sqrt{1-0.8^2} = 0.6$ ticks/second

on the slower rotating M2, ticking at rate of $\sqrt{1-0.4^2} \approx 0.9165$ ticks/second due to time dilation.

M1 does not see her own clock as time dilated and as far as she is concerned, her clock is ticking at a rate of 1 tick/second. Instead she sees signals coming from M2 as coming at a rate of 0.9165/0.6 $\approx$ 1.5275 ticks/second.

By similar reasoning, M2 sees his clock ticking at a rate of 1 tick per second and sees signals coming from M1 at a rate of 0.8/0.9165 $\approx$ 0.6546 ticks/second.

While all 3 observers measure different rates, they all agree that the clock on M1 is ticking at $\approx 0.6546$ of the rate of the clock on M2.
M1 sees M2's clock ticking faster than his own. M2 sees M1's clock as ticking slower than his own. The central COM observer also sees M1 ticking slower than M2.

It might seem counter intuitive to have such a clear result that all observer's agree on, because in relativity sometimes it is difficult to even define which object is faster and usually everything is symmetrical, but in this case rotation (and proper acceleration) is involved and measurements are absolute.

It might also seem slightly odd that M1 sees M2's clock ticking at a rate that is greater than unity, which seems counter to the idea of time dilation.

The reason is that M1 and M2 are not inertial observers but are experiencing proper acceleration and by the equivalence principle they see things as if they are in a gravitational field. M1 has the greater proper acceleration due to traveling the fastest on a longer radius, so M1 feels like she is lower in a gravitational field and sees signals coming from M2 higher up as blue shifted and sped up. Similarly, M2 with the lesser proper acceleration feels like he is higher up in a gravitational field and sees signals coming from M1 lower down as "gravitationally" time dilated and red shifted.

In the above diagram, M1 is lower down in the effective equivalent gravitational field, M2 is midway and the COM is equivalent to an observer that is infinitely far from the "gravitational source" and does not experience any time dilation.

Here is another simple example of non reciprocal time dilation. Consider the Einstein carousel thought experiment. The inertial clock at the centre ticks at a rate of 1 tick per second. The clock on the perimeter ticks at a slower rate due to velocity time dilation. The observer on the perimeter of the carousel that experiences proper acceleration is non inertial and considers the clock at the centre to be ticking faster than his own clock.

Let's say for illustration, the connecting rod is 3 light seconds long and the following parameters apply:

The COM observer will see a clock :

on the faster rotating M1, ticking at rate of $\sqrt{1-0.8^2} = 0.6$ ticks/second

on the slower rotating M2, ticking at rate of $\sqrt{1-0.4^2} \approx 0.9165$ ticks/second due to time dilation.

M1 does not see her own clock as time dilated and as far as she is concerned, her clock is ticking at a rate of 1 tick/second. Instead she sees signals coming from M2 as coming at a rate of 0.9165/0.6 $\approx$ 1.5275 ticks/second.

By similar reasoning, M2 sees his clock ticking at a rate of 1 tick per second and sees signals coming from M1 at a rate of 0.8/0.9165 $\approx$ 0.6546 ticks/second.

While all 3 observers measure different rates, they all agree that the clock on M1 is ticking at $\approx 0.6546$ of the rate of the clock on M2.
M1 sees M2's clock ticking faster than his own. M2 sees M1's clock as ticking slower than his own. The central COM observer also sees M1 ticking slower than M2.

It might seem counter intuitive to have such a clear result that all observer's agree on, because in relativity sometimes it is difficult to even define which object is faster, but in this case rotation is involved and measurements are absolute.

It might also seem slightly odd that M1 sees M2's clock ticking at a rate that is greater than unity, which seems counter to the idea of time dilation.

The reason is that M1 and M2 are not inertial observers but are experiencing proper acceleration and by the equivalence principle they see things as if they are in a gravitational field. M1 has the greater proper acceleration due to traveling the fastest on a longer radius, so M1 feels like she is lower in a gravitational field and sees signals coming from M2 higher up as blue shifted and sped up. Similarly, M2 with the lesser proper acceleration feels like he is higher up in a gravitational field and sees signals coming from M1 lower down as gravitational time dilated and red shifted.

Let's say for illustration, the connecting rod is 3 light seconds long and the following parameters apply:

The COM observer will see a clock :

on the faster rotating M1, ticking at rate of $\sqrt{1-0.8^2} = 0.6$ ticks/second

on the slower rotating M2, ticking at rate of $\sqrt{1-0.4^2} \approx 0.9165$ ticks/second due to time dilation.

M1 does not see her own clock as time dilated and as far as she is concerned, her clock is ticking at a rate of 1 tick/second. Instead she sees signals coming from M2 as coming at a rate of 0.9165/0.6 $\approx$ 1.5275 ticks/second.

By similar reasoning, M2 sees his clock ticking at a rate of 1 tick per second and sees signals coming from M1 at a rate of 0.8/0.9165 $\approx$ 0.6546 ticks/second.

While all 3 observers measure different rates, they all agree that the clock on M1 is ticking at $\approx 0.6546$ of the rate of the clock on M2.
M1 sees M2's clock ticking faster than his own. M2 sees M1's clock as ticking slower than his own. The central COM observer also sees M1 ticking slower than M2.

It might seem counter intuitive to have such a clear result that all observer's agree on, because in relativity sometimes it is difficult to even define which object is faster and usually everything is symmetrical, but in this case rotation (and proper acceleration) is involved and measurements are absolute.

It might also seem slightly odd that M1 sees M2's clock ticking at a rate that is greater than unity, which seems counter to the idea of time dilation.

The reason is that M1 and M2 are not inertial observers but are experiencing proper acceleration and by the equivalence principle they see things as if they are in a gravitational field. M1 has the greater proper acceleration due to traveling the fastest on a longer radius, so M1 feels like she is lower in a gravitational field and sees signals coming from M2 higher up as blue shifted and sped up. Similarly, M2 with the lesser proper acceleration feels like he is higher up in a gravitational field and sees signals coming from M1 lower down as gravitational time dilated and red shifted.

Here is another simple example of non reciprocal time dilation. Consider the Einstein carousel thought experiment. The inertial clock at the centre ticks at a rate of 1 tick per second. The clock on the perimeter ticks at a slower rate due to velocity time dilation. The observer on the perimeter of the carousel that experiences proper acceleration is non inertial and considers the clock at the centre to be ticking faster than his own clock.

Let's say for illustration, the connecting rod is 3 light seconds long and the following parameters apply:

The COM observer will see a clock :

on the faster rotating M1, ticking at rate of $\sqrt{1-0.8^2} = 0.6$ ticks/second

on the slower rotating M2, ticking at rate of $\sqrt{1-0.4^2} \approx 0.9165$ ticks/second due to time dilation.

M1 does not see her own clock as time dilated and as far as she is concerned, her clock is ticking at a rate of 1 tick/second. Instead she sees signals coming from M2 as coming at a rate of 0.9165/0.6 $\approx$ 1.5275 ticks/second.

By similar reasoning, M2 sees his clock ticking at a rate of 1 tick per second and sees signals coming from M1 at a rate of 0.8/0.9165 $\approx$ 0.6546 ticks/second.

While all 3 observers measure different rates, they all agree that the clock on M1 is ticking at $\approx 0.6546$ of the rate of the clock on M2.
M1 sees M2's clock ticking faster than his own. M2 sees M1's clock as ticking slower than his own. The central COM observer also sees M1 ticking slower than M2.

It might seem counter intuitive to have such a clear result that all observer's agree on, because in relativity sometimes it is difficult to even define which object is faster, but in this case rotation is involved and measurements are absolute.

Let's say for illustration, the connecting rod is 3 light seconds long and the following parameters apply:

The COM observer will see a clock :

on the faster rotating M1, ticking at rate of $\sqrt{1-0.8^2} = 0.6$ ticks/second

on the slower rotating M2, ticking at rate of $\sqrt{1-0.4^2} \approx 0.9165$ ticks/second due to time dilation.

M1 does not see her own clock as time dilated and as far as she is concerned, her clock is ticking at a rate of 1 tick/second. Instead she sees signals coming from M2 as coming at a rate of 0.9165/0.6 $\approx$ 1.5275 ticks/second.

By similar reasoning, M2 sees his clock ticking at a rate of 1 tick per second and sees signals coming from M1 at a rate of 0.8/0.9165 $\approx$ 0.6546 ticks/second.

While all 3 observers measure different rates, they all agree that the clock on M1 is ticking at $\approx 0.6546$ of the rate of the clock on M2.
M1 sees M2's clock ticking faster than his own. M2 sees M1's clock as ticking slower than his own. The central COM observer also sees M1 ticking slower than M2.

It might seem counter intuitive to have such a clear result that all observer's agree on, because in relativity sometimes it is difficult to even define which object is faster, but in this case rotation is involved and measurements are absolute.

It might also seem slightly odd that M1 sees M2's clock ticking at a rate that is greater than unity, which seems counter to the idea of time dilation.

The reason is that M1 and M2 are not inertial observers but are experiencing proper acceleration and by the equivalence principle they see things as if they are in a gravitational field. M1 has the greater proper acceleration due to traveling the fastest on a longer radius, so M1 feels like she is lower in a gravitational field and sees signals coming from M2 higher up as blue shifted and sped up. Similarly, M2 with the lesser proper acceleration feels like he is higher up in a gravitational field and sees signals coming from M1 lower down as gravitational time dilated and red shifted.