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I don't know enough about the subject to know that I am wrong.

Eric Sumarnkant
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The speed of light is ~ $3\times10^8$ m/s. That's how far a photon travels per second in a vacuum. It doesn't make sense to ask what the speed of time is because time isn't an object that moves through space.

Nick M
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  • Why does it seem to me that 1 second travels at exactly the same speed of light? Like they are two cars on the freeway moving parallel to each other? – Eric Sumarnkant May 15 '20 at 14:32
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    @EricSumarnkant Time does not "travel", it doesn't make sense to ask at what speed it is moving or travelling. – Charlie May 15 '20 at 14:34
  • Nothing can travel faster than the speed of light but time (1 second) travels just as fast as the speed of light, right? – Eric Sumarnkant May 15 '20 at 14:34
  • "Speed" has a specific meaning in physics: get a timer, watch an object for an amount of time $T$, measure the difference between its starting position and ending position in that amount of time $D$, and then divide $D$ by $T$. By this definition time cannot travel because time does not have a position. There's no way to compare "the speed of time" with "the speed of light" because the definition of "speed" does not apply to time. – Luke Pritchett May 15 '20 at 14:40
  • Do physics know everything there is to know about time (a done deal) OR are there things we don't understand about time? – Eric Sumarnkant May 15 '20 at 14:41
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  • How fast does time move? I would say: 60 seconds per minute.
  • How fast does my soup heat up? I would say: with 3 degrees Celsius per minute.

But now try to answer this:

  • Is the speed of time faster than the speed of light? Meaning, does time flow faster than light moves?
  • Is the speed of temperature increase faster than the speed of light? Meaning, does the temperature increases faster than light moves?

These questions unfortunately do not make sense. Light's speed is a distance-per-time measure. The other two are time-per-time and temperature-per-time measures. They do not apply within the same dimensions; they are not comparable.

So, unfortunately, the question has no meaning and is unanswerable. Sort of like asking Is the sky more blue than the sun is hot?

Steeven
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  • In Einstein's equation C = 3×10^8 m/s. So this must mean 1 second equals 3×10^8 m OR 3×10^8 m = 1 second. 3rd grade division teaches us this, right? – Eric Sumarnkant May 15 '20 at 14:46
  • @EricSumarnkant Sure, the speed of light is about $c=3\times 10^8 ,\mathrm{m/s}$ in vacuum. This is how many metres light moves during 1 second. Just to have the semantic wording right, 1 second does not equal $3\times 10^8 ,\mathrm{m}$, but it does correspond to light having moved $3\times 10^8 ,\mathrm{m}$, yes. – Steeven May 15 '20 at 14:55
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    @Eric Well, in special relativity, a temporal duration of 1 second has the same magnitude as a spatial displacement of 299792458 metres. But it's not quite right to say they are completely equal, because there are important differences between a timelike interval and a spacelike interval. In particular, all observers agree on whether a given spacetime interval is timelike, lightlike, or spacelike. – PM 2Ring May 15 '20 at 14:57
  • Wouldn't time be different on every planet out there? We base time on how long the earth travels around the sun, our sun? This worries me. Do physicists understand time completely (A DONE DEAL) or are there things we don't understand about time? I am using my computer and it seems like they got it right. But there is a lingering doubt. Can you clarify that scientist got this right? – Eric Sumarnkant May 15 '20 at 15:06
  • my head hurts thinking about this its hard for me to comprehend – Eric Sumarnkant May 15 '20 at 15:16
  • @Erik No, we don't define time on the motion around the sun. We are able to measure the speed of light and other phenomena here in earth that would also be the same elsewhere, at least in all other parts of the universe that we have observed. So, time is the same everywhere. But time does dilate with speed, which is a part of the relativity theory. – Steeven May 15 '20 at 16:14