The discussion revolves around the concept of time dilation and synchronization of clocks in different locations, particularly in relation to a pulsar. Participants explore the implications of sending clocks at high velocities and how their measurements of time may differ based on their positions and movements relative to the pulsar.
Participants express differing views on the nature of clocks and time measurement, with no consensus reached on the implications of sending clocks at high velocities or the feasibility of synchronization over large distances.
Participants highlight the complexity of synchronizing clocks and the dependence on definitions and reference frames, indicating that the discussion involves unresolved assumptions and varying interpretations of time measurement.
This discussion may be of interest to those exploring concepts of time dilation, synchronization of clocks, and the implications of relativity in practical scenarios.
This is rather confused. Clocks measure their own proper time - they don't use reference frames.maxpower2020 said:What if two clocks used the same reference frame?
These aren't really clocks, if I understand your setup. They're basically counters attached to telescopes and they count the pulsar flashes they see.maxpower2020 said:For instance, 2 countdown clocks using a particular pulsar as a measure of time.
Depends where they are in relation to the pulsar and what you mean by "the same time". If the counter that you move goes directly towards the pulsar then it will see pulses earlier than the stationary counter, so will finish earlier. If the counter moves directly away then it will receive pulses later and finish later. If it moves in any other direction then it's frame dependent - there exists a frame in which they finish simultaneously, but there are frames in which either counter finishes first.maxpower2020 said:One stays here, the other is sent 100 million miles away at a very high velocity. Would they still reach 000 at the same time?
Suppose one were sent directly toward the pulsar and one directly away from it. Do you think it would take the same amount of time for each to accumulate the same number of pulsar-ticks?maxpower2020 said:Question about time dilation. What if two clocks used the same reference frame? For instance, 2 countdown clocks using a particular pulsar as a measure of time. One stays here, the other is sent 100 million miles away at a very high velocity. Would they still reach 000 at the same time?
Yes, it is called a “frequency standard”. A clock is a frequency standard with a counter, but the frequency standard is the thing that makes a clock a clock.maxpower2020 said:Is not a cesium clock (or any other) just a frequency counter?
Measurement of time is not arbitrary. The units used are, sure. But once you've agreed that, a second is a second is a second and had nothing to do with reference frames, gravity, or anything else. All that kind of thing comes in when you want to work out what my clock says at the same time yours says 12.00.00. Furthermore, two correctly calibrated clocks sitting side by side will tick at the same rate. That isn't arbitrary behaviour.maxpower2020 said:Okay I understand more and am confused even more. First off measurement of time is totally arbitrary, it depends on what we all agree upon. Our clocks on Earth are measured in our gravity, and in our reference frame, and on a agreed upon definition of a second.
Not quite. It's a frequency counter with a stable cyclic process - a source of pulses with a fixed frequency. Your counters aren't attached to the source, so they don't see a fixed frequency due to the Doppler effect - so they will sometimes count at the same rate as a clock sitting next to them and sometimes won't. So they aren't really clocks.maxpower2020 said:Is not a cesium clock (or any other) just a frequency counter?
A great many ways, most giving different results. One of the lessons of relativity that seems to be the hardest to learn is that "synchronised clocks" is not a complete concept. You need to specify your synchronisation process and the states of motion of the clocks that are being synchronised. And you need to accept that no process gives clocks that everyone will reasonably describe as synchronised.maxpower2020 said:My original thought was if there was any way to keep 2 clocks in sync, one here one there.
Ibix said:so will finish earlier.
phinds said:Do you think it would take the same amount of time
Mine was a specific statement about when the pulsar and both counters are in a straight line ("the counter that you move goes directly towards the pulsar"). In this case the reception events of a particular pulse are null separated and order is invariant. When the three are not colinear then the reception events are spacelike separated and the order depends on frame.Grinkle said:Please, I'd like to confirm the invoked frame is in these two statements -
It makes no difference which reference frame you use to take the measurement. The clock measures the passage of its own (i.e. proper) time, something that's the same in all reference frames.maxpower2020 said:Our clocks on Earth are measured in our gravity, and in our reference frame, and on a agreed upon definition of a second.