Time Travel, Light Speed, and Relativity

Post by **ccb056** » May 5th, 2004, 1:44 am

We are learing about time travel, light speed, and general/specific relativity now in Physics class. So far, everything has just been a review of what I have already been self-taught. Some examples are:

Time slows down the closer you approach lightspeed.
It takes an infinite amount of energy to reach lightspeed.
You can break lightspeed by cheating, bending the space time continuim.
Gravity, more specifically mass, affect the space time contimium.
There is no such thing as a "Flux Capacitor".

Anyone want to talk about time travel?

This should provide for some good reading: http://math.ucr.edu/home/baez/physics/R ... t/FTL.html

Smartweb · Post by **Smartweb** » May 5th, 2004, 2:09 am

As long as its more serious than the John Titor crap, lets talk. How accurate is the presentation in Back to the Future?

Post by **ccb056** » May 5th, 2004, 2:11 am

It's been a while since I've seen Back to the Future, maybe 3 or 4 years, and at the time I saw it, I was more interested in the Delorean than the space time contimuim.

Can you explain how the doc gets the Flux Capacitor to work in the Delorean with that radioactive junk and what it's supposed to do? If so, I can shoot off theories and stuff to either support or oppose it.

The Star Trek stuff may seem far out, but hyperspace and warp drives are theoritically possible.

One thing that I find quite interesting is this situation:

You are riding in a car at 70 mph, you throw a ball forward at 5mph, the ball is moving relative to the earth at 75mph
However, you are moving at 1/2 the speed of light, you throw a ball at 1/2 the speed of light, the ball is not moving at the speed of light.

Smartweb · Post by **Smartweb** » May 5th, 2004, 2:26 am

ccb056 wrote:One thing that I find quite interesting is this situation:

You are riding in a car at 70 mph, you throw a ball forward at 5mph, the ball is moving relative to the earth at 75mph
However, you are moving at 1/2 the speed of light, you throw a ball at 1/2 the speed of light, the ball is not moving at the speed of light.

All that means is we need a logarithmic method (I think) to measure speed, right?

Post by **ccb056** » May 5th, 2004, 2:31 am

right, and here it is:

V=(V1+V2)/(1+(V1*V2)/c^2)

Smartweb · Post by **Smartweb** » May 5th, 2004, 2:41 am

I'm terrible at this stuff. What is a flux capacitor?

Post by **ccb056** » May 5th, 2004, 2:44 am

It doesn't exist.

There was a young lady named Bright,
Whose speed was far faster than light.
She went out one day,
In a relative way,
And returned the previous night!

-Reginald Buller

Post by **ccb056** » May 5th, 2004, 11:44 pm

This equation is true:
V=(V1+V2)/(1+(V1*V2)/c^2)

but when you plug in c^2 for both V1 and V2 you get the total velocity as 2m/s

anyone know why?