So weird, after visiting, my mouse icon disappears!

The most obvious thing would be that we and other creatures would have sight as a secondary sense. If light went that slowly we would have to develop other ways of navigating the world, such as echolocation, smell or touch.

Then we will never be able to see aliens again.

in the real world if the speed of light was 5 km, we'd probably be a lot smaller!

"What if the speed of light was 5 km/h?"

Website loads in few ms

Nahh it's not

Um, speed of light and gravity are so fundamentally linked that nothing you see would look like that. Just changing speed of light but not adjusting anything else makes little sense.

I don’t quite get the assumptions here. If c were actually 5 km/h, causal influences would propagate much more slowly. With G unchanged, planets and stars at their current masses and sizes would lie within their Schwarzschild radii. Any rock greater that 1.5km in radius is a blackhole. With c reduced to 5 km/h, the black-hole threshold would correspond to a surface escape speed of just 5 km/h. Holding the other relevant constants fixed would also radically alter atomic structure and chemistry. It seems like a lot would change before we could be around to observe the cool redshifts. Is the reduced c being applied only to the visual effects?

Now I'm curious what the evolutionary ramifications of this would be.

cool idea, but being vibe coded doesn't inspire much confidence on whether the math or author subject understanding is correct.

As such I wouldn't base my understanding on the subject on this as-is. Which is a shame as, if it was actually hand coded I might actually use this to learn relativity, something which would otherwise be out of my reach.

A note on source code, I think committing the actual javascript code and such is a mistake at the level of committing compiled binaries to a repo. It's more useful, correct and genuine to upload the prompts used, which are the source code that generates the target code, and upon which the author and others can study and modify the program.

That said, as an idea, it reminds me of Kay's dynabook example ( https://dl.acm.org/doi/10.1145/800193.1971922 ) :

"Here look." Her fingers started to fly on the DynaBook's keyboard, altering the program she had·written several weeks before .. You justact as though the ship is pointed towards the sun and add speed!· As she spoke her ship started to fall, but not towards the sun. Oh no!..·"

If we want to move closer to that ideal, of interactive education, I don't think we can just apply the old forms and use the LLM to aid one in being the allmighty program-creator, the LLM needs to be placed at the service of the user. I can't help but seeing the usage of LLMs to generate code as misplacing this power. It's as if a new powerful metal were discovered and smiths can only think about making hammers and foundries and casts with that metal, considering it too valuable to actually use it for the products being smithed.

Would mean the biomolecular computers would be faster than electronics.

Electronics wouldnt work at all.