Re: A89: What's Wrong?
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Re: A89: What's Wrong?
>
>One's mass approaches infinity as one gets nearer to the speed of light.
>Since this problem happens first, it should be tackled before your
>question of what happens once one goes faster than light.
>
>-Adam
>
True, and as the mass increases, the amount of energy required to accelerate
the object also increases, therefore it takes an infinite amount of energy
to get something to go the speed of light. I admit that I don't understand
this stuff in the slightest, I'm just restating something I read (and didn't
understand) in Stephen Hawking's book "A Brief History of Time". The thing
that throws me off is the question of why light itself doesn't have infinite
mass. One can argue that light doesn't have mass to begin with, therefore
when you multiply its mass by infinity, you still have 0. But it is known
(and predicted by Einstein's general theory of relativity) that light is
affected by massive objects. Hawking mentions briefly that objects travel in
straight lines through space-time, but these lines appear as geodesics in
out 3 dimensional perception (due to the warping of space-time that occurs
around massive objects), which is the foundation of gravity (or something
like that). Light travels in geodesics as well, so at first that seems to
explain it... But it seems to assume that only one body is warping
space-time. If the mass of the light passing by a star has no effect, then
how is it different for a planet? Wouldn't the planet's mass have no effect?
Obviously it does. So light still seems to be an exception to the rule. Am I
the only one who is confused by this?
-Kevin
PS: Here's a little part from Hawking's book that I liked: "... the concept
of time has no meaning before the beginning of the universe. This was first
pointed out by St. Augustine. When asked: 'What did God do before he created
the universe?' Augustine didn't reply: 'He was preparing Hell for people who
asked such questions.' Instead, he said that time was a property of the
universe that God created, and that time did not exist before the beginning
of the universe."
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