Einstein's Light Clock: The Mind-Blowing Experiment That Proved Time Isn't Real | Joe Rogan

Ajouté : 2026-06-02

[00:00:00]But if that's the case, so subjectively we can measure things. We can measure time.

[00:00:08]But But what are we measuring?

[00:00:11]If it's I mean are we making artificial time constraints? Are we Are we doing it ourselves? When we When we create a clock, we create a watch. And the watch is, you know, 24 hours a day, it's running.

[00:00:24]What is it What is it measuring?

[00:00:27]Right?

[00:00:28]>> That is exactly the question Albert Einstein asked. That That is That is a deep, excellent question.

[00:00:36]And And so that was the problem. I mean in a famous thought experiment, Einstein made a clock by setting up two mirrors and having light bounce between the two mirrors. And that was the tick of the clock. Tick tick tick tick tick.

[00:00:47]And And the problem was that you know, that's how he started thinking about the speed of light is that if you had this thing in a spaceship that was going a huge fraction of the speed of light, then a person standing watching it go by would actually watch the light kind of trace out a pattern like this. Cuz you know, it's it's it's actually ticking between the mirrors, but the mirrors are moving along. And so you see the light make this sort of bouncing movement. And that means it's actually traveled farther than the person on the ground who thinks that the mirrors are just sort of the light is making just a a straight up and down line from mirror to mirror.

[00:01:16]That That question that you asked is what completely I mean, it completely revolutionized physics. Everything fell apart when people said, "How do you even measure time? What does it mean to make a clock?

[00:01:28]What are we measuring?"

[00:01:31]>> I still don't understand what we're measuring.

[00:01:32]>> Oh, lord. [laughter] Yeah.

[00:01:34]>> I I get it. I mean, we >> I I don't know if I have an answer for you. I don't think anybody does. But But But here's the deal. So, the the clock in Einstein's experiment So, the the the the clock has, you know, two mirrors and there's light bouncing between it. And then And that's the distance that it travels in one tick.

[00:01:51]>> Right.

[00:01:52]>> But now you put this mirror You put that clock on a spaceship and the spaceship's going really fast. And as it goes by, you see that that that clock as as it streams by you really fast, you see the light make this motion.

[00:02:04]And And this line is actually longer than that line.

[00:02:08]This this line, if you measure it, that is actually a longer line that I drew than the the original one between just the two mirrors cuz now it's at an angle.

[00:02:16]And this is what made Einstein say, "Time has to change. If anything moves, the tick of a clock change." So, whatever you measure time, whatever time is, whether you measure it with a bouncing clock, or whether you measure it with a vibrating atom like we do in the Bureau of Standards, or whether you measure it with a spring that's slowly unwinding in a wristwatch, anything you can do to measure one moment to the next changes when motion is involved. There's no way to get around it. It's not just the measurement. It's time itself is changing. Any way we have to measure this thing we call time.

[00:02:53]And I have to tell you, Joe, I I don't think we have an answer to what time is.

[00:02:58]What are we measuring?

[00:03:01]I think I think right there, I think you're asking for the next revolution in physics that we don't have yet. I really mean that.

[00:03:08]>> So, when we're measuring time currently, like when I walked looked down at my watch, I'm measuring time in this particular space. Like where I am, what altitude I'm at, how fast I'm moving, and the watch just does a reasonable job of calculating all that.

[00:03:26]>> And that's And that's you. I mean, that's what you see here sitting still with your watch looking at it.

[00:03:31]>> Right.

[00:03:31]>> If someone's flying by at close to the speed of light, they won't see you measure time the same way. Yeah.

[00:03:36]>> We