Hacker News new | ask | show | jobs
by 3825 3410 days ago
(Please pardon my ignorance and lack of proper terminologies. I'm not a scientist.)

Does faster than light mean instantaneous? Is there no "speed limit" (that we know of) above the speed of light?

3 comments

> Is there no "speed limit" (that we know of) above the speed of light?

No. But as far as we know, the speed of light is an absolute speed limit.

Faster than light doesn't mean instantaneous it can but doesn't have too.

Objects can move relatively at greater speeds than light when you account for the expansion of the universe.

Other hypothetical modes of transportation such as wormholes, hyperspace or quantum slip space allow you to take shortcuts but often there will be travel time involved.

Objects far apart from one another move at relatively greater speeds after accounting for the expansion of the universe simply because there's new space getting created in between. Nothing moves faster than light relative to its local surroundings.
Yes which is exactly what was said.
The speed of light is ultimate. Nothing travels faster than light. Furthermore it is not arbitrary but emerges from the geometry of space time. Talking about a limit above it doesn't really make physical sense.
If the speed of light can be exceeded by manipulating space itself, ala a warp drive, couldn't there perhaps be (currently unknown) laws governing spatial expansion and contraction that would effectively set another higher speed limit?
Our current understanding of physics puts a hard limit on matter traveling at or above the speed of light as your mass increases as you approach the speed of light requiring an ever greater (infinite amount of energy) to get you there. With that being said, we still don't have a perfect understanding of physics, so there is wiggle room. However, our models are really good both on the drawing board and in observation, so it looks unlikely at this stage (I'm not a physicist, but read the dumbed down books they publish for the masses).
That's not exceeding the speed of light. That's changing the distance you need to go so that you can get to where you want to be at sublight speeds in reasonable time.
When you think about the number open questions in theoretical physics, and the fundamental importance they have to filling in the still large gaps in our understanding of nature, shouldn't your statement be qualified just a bit?