Re: A89: What's Wrong?


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Re: A89: What's Wrong?




I like your regurgitation of Stephen Hawking's book.  It's pretty well
stated.  However, on the question of light.  To say that light is affected
by massive objects was not my interpretation of the book.  Instead, I read
it as spacetime is affected by the massive objects, and light is just
following a geodesic in spacetime.  Light therefore, is not affected by a
massive object, but is still going in a straight line.  The only thing
affected by the massive object would be spacetime.

Peter

If one is travelling faster than light, would he be able to get e-mail?
----- Original Message -----
From: Kevin Goodsell <goodsell@bridgernet.com>
To: <assembly-89@lists.ticalc.org>
Sent: Tuesday, January 09, 2001 1:05 AM
Subject: 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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