3 ms·
She wrote several followup answers in the comments thread, one of which addresses your question (though it might not be satisfying!): http://www.reddit.com/r/as
by kalvin 16y ago
She wrote several followup answers in the comments thread, one of which addresses your question (though it might not be satisfying!): http://www.reddit.com/r/askscience/comments/fjwkh/why_exactly_can_nothing_go_faster_than_the_speed/c1gi47a http://www.reddit.com/r/askscience/comments/fjwkh/why_exactl...
Someone else wrote my favorite answer: "Basically, the way to think of it is not that light is the fastest thing, but rather that there is a speed, c, which the geometry of space and time demands is the fastest possible speed.
One can also work out that anything without mass must travel at this fastest possible speed c. Light is one of those things, therefore light travels at c. It's only an accident of history that we call c "the speed of light": that's the context we discovered c's existence in.
As for why it's the speed it is, well, it's the speed in our universe. It's actually much more natural to say c=1 and all speeds are then unitless numbers between 0 and 1. From this point of view c is 300 Mm/s because of how we chose to define the meter and the second." http://www.reddit.com/r/askscience/comments/fjwkh/why_exactly_can_nothing_go_faster_than_the_speed/c1gi276 http://www.reddit.com/r/askscience/comments/fjwkh/why_exactl...
- scorpion032 16y agoAs of today, meter is defined in terms of the speed of light. We have come a full circle! > The meter is the length of the path travelled by light in vacuum during a time interval of 1/299 792 458 of a second. via: http://physics.nist.gov/cuu/Units/meter.html http://physics.nist.gov/cuu/Units/meter.html
- beza1e1 16y agoSo how long is a second?
- a1k0n 16y agovia Wikipedia: The duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom. So I guess that means a meter is 30.66331898849836976219 cesium-133 transition periods.
- oewolf 16y agoThis clarified a few questions I had. Hope you can help me with a couple: why is there even a limit? how do we know there is an insuperable barrier nothing can cross for sure?
- perlgeek 16y agoA physicist can never certainly say that something doesn't happen. We have models that describe the world very well, but those models are never the whole truth (and even it were, we couldn't be sure of it). Special and General Relativity are experimentally very well tested, and these theories predict that a particle that has a speed < c can never acquire a speed > c. There are solutions for speeds larger than c, but those solutions are quite weird, and can't interact with "normal" particles. But the mere scientific approach of observing facts, modeling and verifying means that one can never be sure that something can't be - only in the limits of the models can we be sure that a thing can't be.