|
|
|
|
|
|
by jjtheblunt
2498 days ago
|
|
|
I'm curious why you write what you wrote: at Fermilab, where some high school students took physics including from a Nobel laureate, I remember (as a high school student) that the problem with exceeding the speed of light, from the point of view of a reference frame, is that, if e = mass * celeritas^2 / Sqrt( 1 - velocity^2/celeritas^2 ) describes relativistic mass and energy conversion, where i spelled out c as celeritas as the speed of light,
at least in the reference frame, something implausible is implied. Looking at that equation, as an object's velocity approaches the speed of light, the denominator approaches zero, and the equivalent energy of the moving mass goes towards infinity. That led to the quandary : can you really get something to go that fast? (I'm on a keyboard with no paper to fiddle with, or I'd further monkey with the equations.) |
|
|
The flaw is that you don't gain mass as you go faster. You gain momentum. That momentum energy even causes gravity in a way[1].
The reason it seems to take infinite energy to go faster than light is that the rate of time for the traveler changes as they go faster. From your observer's perspective, whenever they accelerate the speed increase is exactly cancelled out by the change in relative time rates. The more energy they spend the faster they go, but never quite fast enough to go at C.
From the traveler's perspective it is a totally different adventure. When they add energy they accelerate. Period. They don't notice the time dilation outside of observations of their origin and destination. If they have enough fuel, they can accelerate smoothly to 2 times the speed of light and travel a light year in 6 months. The problem is that more than a year will have gone by in the origin and destination on the way and they were never observed going faster than C.
If we had a way around the rocket equation we could easily cross the Galaxy within a human lifetime. It would just be Earth would be gone by the time we got there.
[1]https://physics.stackexchange.com/questions/63961/does-relat...