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Author Topic: gravity  (Read 2616 times)

Offline thebrain13

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gravity
« on: 03/10/2007 03:21:34 »
why do photons (or other objects moving almost at c)fall twice as fast as other more stationary objects?
« Last Edit: 12/10/2007 21:04:20 by thebrain13 »


 

Offline Atomic-S

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gravity
« Reply #1 on: 03/10/2007 06:23:06 »
They do?
 

Offline thebrain13

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gravity
« Reply #2 on: 03/10/2007 17:41:30 »
ya, isn't that the first big proof of general relativity? Einstein predicted photons would fall twice as fast as other, relatively stationary objects, paralax proved that.
 

Offline lightarrow

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gravity
« Reply #3 on: 03/10/2007 20:29:27 »
why do photons fall twice as fast as other objects?
Let's state this more correctly: the bending of light according to GR is twice the bending of light according to newtonian mechanics. The last exist (I didn't know it until some months ago) and can be computed making the limit for mass-->0 of the bending of a particle's trajectory.

So, it's twice with respect to other non-relativistic objects, not respect to every other object.

However, I don't know why this factor two. And I really would like to know it too!
« Last Edit: 04/10/2007 12:47:17 by lightarrow »
 

Offline thebrain13

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gravity
« Reply #4 on: 08/10/2007 19:21:22 »
come on somebody has to know the answer?
« Last Edit: 12/10/2007 21:05:36 by thebrain13 »
 

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gravity
« Reply #4 on: 08/10/2007 19:21:22 »

 

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