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Answer for “Which is Faster? Expansion of Universe or Speed of Light?”

In this video, we will give you the answer.
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Today I present an interesting question. So, here please take a look at here. So this is the so-called Hubble diagram. This is as a function of distance x-axis is distance, y-axis is the resistance speed of galaxies. So, the more distant galaxies are moving away from us faster, so nearby galaxies moving away from us in smaller speed, more distant ones are faster speed. So, this is how Hubble, Edwin Hubble, found the expansion of the universe, this means the universe is expanding. This, that’s why it’s called the Hubble Diagram. Fine, but if you look at the y-axis, the velocity, the velocity is very large.
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And then here, the speed of the light is 30,000 kilometers per second, kilometers per second, so the speed of the light is here, and in some galaxies here, are flying away from us faster than the speed of the light. Is this okay? In general relativity Einstein said nothing can travel faster than light. But these galaxies are moving away from us faster than the speed of the light. What’s happening here? Is the universe violating the general relativity? What do you think?
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The answer is, galaxies are not moving, but the space itself is expanding, so it’s not violating general relativity. Uh, please look here, there are two galaxies here, here, and the universe is expanding, so these galaxies are moving away from each other, with certain velocity and if these two galaxies are separated well enough, the speed of this moving away, the speed to for them to move away is faster than speed of the light. However, these two galaxies themselves are not themselves, are not moving. It’s that space expanding faster than the speed of the light. But these two galaxies are just sitting in the space. So this is not violating general relativity.
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For example, if this galaxy emitted light, or to the other galaxy, say “hello” to the other galaxy, this information is not going to fly any faster than the speed of the light. If it’s just space is expanding so, you know, that doesn’t mean information is going to go from here to other, or from here to here, faster than the speed of the light. So, both expansion of the universe, expansion speed of the universe and the genera- general relativity are still consistent to each other.

So which is faster? Expansion of universe or speed of light?

Place your bets, everyone, as Prof. Goto will now reveal the answer to this question in this video. Let us know whether you got the right answer or not!

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Mysteries Of The Universe

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