this post was submitted on 15 Jun 2024
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...but that's exactly what you're doing. The fact that light travels at the same speed in all directions cannot be proven. You're the one insisting that it does.
I'm not insisting anything. I'm saying that, based on everything we know, the direction of light has no bearing on its speed.
Suggesting that it does just because we don't have evidence that it doesn't is no different, as I said, as claiming the universe was created last Thursday.
Maybe the speed of light doubles when it goes through the exact right type of orange. You can't prove it doesn't.
This is slighlty different though, we only know the two-way speed of light, not the one way speed of light.
We only know that this trip, to and back, takes x seconds. We cannot prove that the trip to the mirror takes the same length of time as the way back.
The special theory of relativity for example does not depend on the one way speed of light to be the same as the two way speed of light.
Wiki
With a detector and very accurate clocks, it would be easy to say "I'm going to send a pulse at 2pm, record when you receive it" that's measuring it in one direction
The very accurate clock needed in this case is physically impossible as far as we know, there's no way to measure it as far as our current understanding of physics goes.
Though if you can figure out a way you should publish a paper about it.
Can you cite some literature to back up that claim? Stating that something like acceptable clock synchronisation (a well established and appreciated method in the measurements of physical effects) is impossible in and of itself is something so bold that no one can just take your word for it.
It is impossible to synchronize the clocks in such a way that you can actually measure the speed of light with it due to time dilation unless you define beforehand how fast the speed of light is to calculate that time dilation.
See also This or, more accessibly "Synchronization conventions"
The clocks involved in gps are accurate enough that they have to take relatively into account for gps to be accurate. That's far more accurate than you need to measure the speed of light.
And to calculate the offset needed to get them all synced up involves calculating time dilation, which involves knowing/assuming the speed of light. These synchronizations work just as well if the two way speed of light is different than the one way speed of light.
To know the speed of light you assume the speed of light is c, but you're trying to calculate c so all those clocks aren't verified synced.
Just read through the wiki or Harvard's books if you'd like, this is an unsolved "problem" in physics for a reason or do you think no one cares about how fast c is?
See also This or, more accessibly "Synchronization conventions"
I read all those and every test has reduced the amount that the speed of light could be anisotropic. From "it could be twice as fast in this direction to the other" to "it could be a small fraction of the relativistic effect of moving a clock through space." Every improvement in measurement trends towards isotropic.