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Show HN: What if the speed of light was 5 km/h?

rivendell.dmitrybrant.com

171–180 of 213 posts

Re: Show HN: What if the speed of light was 5 km/h?

#171

Some time ago I had the following shower thought: "the Speed of Light is pretty slow" How i got there: The closest major galaxy to the Milky Way is Andromeda, and is 2.5 million! light-years away. And this is the CLOSEST galaxy, the universe is extremely big. Of course that as you get closer to C, the traveling object will experience time dilation (relative to observer), so the time passed will be less. At 99.999% C,…

I wonder what the light equivalent of a sonic boom is.

Re: Show HN: What if the speed of light was 5 km/h?

#172

Wait if the speed of light were different, wouldn't atoms be a different size? And so the entire world would be a different size?

I suspect all the relative proportions would remain the same. And that we come to the conclusion that our definition of speed is rather arbitrary.

Re: Show HN: What if the speed of light was 5 km/h?

#174

Some time ago I had the following shower thought: "the Speed of Light is pretty slow" How i got there: The closest major galaxy to the Milky Way is Andromeda, and is 2.5 million! light-years away. And this is the CLOSEST galaxy, the universe is extremely big. Of course that as you get closer to C, the traveling object will experience time dilation (relative to observer), so the time passed will be less. At 99.999% C,…

I wonder what the light equivalent of a sonic boom is.

Cherenkov light

Re: Show HN: What if the speed of light was 5 km/h?

#176
Here is my prediction. If the speed of light were 5 km/s, it would be slower than the speed of sound; consequently, the sound would reach me much faster than the visual image. For instance, if I were surrounded by ten people and one of them clapped, I would hear the sound first and only realize who had clapped quite a while later.

Re: Show HN: What if the speed of light was 5 km/h?

#177
post #44

Whenever I think about light speed being fast, I imagine myself standing at the edge of the solar system and watching a hypothetical photon travel from the Sun to the Earth and taking 8 minutes. Suddenly it doesn't feel like light is really all that fast except at human scales. 5 km/h would be fascinating though.

The speed of light is unbelievably slow, not even as a cosmic scale, but on earth. We cannot play competitive multiplayer games globally, without 300ms ping. I dream of a world playing Black Ops 2 on a original PS3 in 2026 getting into a lobby because latency is low.

Still not as unbelievably slow as signals in our body. If you hook up a fiber connection from a button to an LED, then stub your toe on the button, the fiber can be thousands of kilometers long and you'll still (via the LED) see that you've stubbed your toe before you feel it.

This is of course assuming instant activation, a direct connection and no additional latency from network hardware.

Re: Show HN: What if the speed of light was 5 km/h?

#178
This is very cool, but what mechanism lets me see the roof of the cars on the big wheel?

The cars seem to twist towards me as they approach and away from me as they recede, but from my initial stationary position, which is below the roof of the lowest car, I feel that I shouldn’t ever be able to see light from the top surface of a car’s roof?

If I toggle ‘L’ off then indeed, I can’t see the top of any of those cars. But I feel that even with it on, and in the absence of gravitational lensing, I feel the path of light from that top surface would always be blocked?

Re: Show HN: What if the speed of light was 5 km/h?

#179

Here is my prediction. If the speed of light were 5 km/s, it would be slower than the speed of sound; consequently, the sound would reach me much faster than the visual image. For instance, if I were surrounded by ten people and one of them clapped, I would hear the sound first and only realize who had clapped quite a while later.

Sound is a wave that travels through some medium, which also cannot be faster than light. You can't have FTL information transfer.
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