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Author Topic: How do we handle infinite frames?  (Read 1403 times)

Offline jeffreyH

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How do we handle infinite frames?
« on: 23/02/2014 01:24:59 »
Let's take a frame A, in frame A an observer detects an object moving at 99% c in frame B. In frame B an observer detects an object moving at 99% c in frame C. In frame C an observer detects an object moving at 99% c in frame D. Etc, etc ad infinitum. At what point does this interpretation break down? We can continue it infinitely.


 

Offline jeffreyH

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Re: How do we handle infinite frames?
« Reply #1 on: 23/02/2014 01:45:10 »
I think by the time we get down to the Planck length scale this progression will fail. That is when observer A detects two successive objects moving with a difference of 1 Planck length relative to each other. What then?
« Last Edit: 23/02/2014 01:49:14 by jeffreyH »
 

Offline evan_au

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Re: How do we handle infinite frames?
« Reply #2 on: 23/02/2014 03:26:54 »
When velocities approach a percentage of c, velocities do not add linearly (or even close to it).
See: http://en.wikipedia.org/wiki/Velocity-addition_formula
 

Offline jeffreyH

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Re: How do we handle infinite frames?
« Reply #3 on: 23/02/2014 04:02:27 »
When velocities approach a percentage of c, velocities do not add linearly (or even close to it).
See: http://en.wikipedia.org/wiki/Velocity-addition_formula

Yes but at some point a violation has to occur. This series approaches infinity so what is the limit? I certainly don't relish calculating that.
 

Offline Bill S

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Re: How do we handle infinite frames?
« Reply #4 on: 23/02/2014 18:25:33 »
Quote
This series approaches infinity so what is the limit? I certainly don't relish calculating that.

I certainly would not be capable of calculating that!  To me it simply highlights the confusion when mathematical "infinities" are assumed be infinite.

If something is not infinite, it must be finite.  How can you claim that something finite "approaches" infinity.  However much it travels/increases/changes it is still infinitely far from becoming infinite.
 

Offline Phractality

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Re: How do we handle infinite frames?
« Reply #5 on: 23/02/2014 21:22:50 »
Let's take a frame A, in frame A an observer detects an object moving at 99% c in frame B. In frame B an observer detects an object moving at 99% c in frame C. In frame C an observer detects an object moving at 99% c in frame D. Etc, etc ad infinitum. At what point does this interpretation break down? We can continue it infinitely.
Which interpretation do you expect to break down? Are you talking about adding relative velocities? The velocity the object relative to the observer in A does not approach infinity; it approaches c.

.99 c + .99 c = 0.99995 c.
0.99995 c + 0.99995 c = 0.999999999 c
 

Offline jeffreyH

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Re: How do we handle infinite frames?
« Reply #6 on: 23/02/2014 23:43:01 »
Quote
This series approaches infinity so what is the limit? I certainly don't relish calculating that.

I certainly would not be capable of calculating that!  To me it simply highlights the confusion when mathematical "infinities" are assumed be infinite.

If something is not infinite, it must be finite.  How can you claim that something finite "approaches" infinity.  However much it travels/increases/changes it is still infinitely far from becoming infinite.

This is the problem with infinities in theories. They can occur at absolute values past which physics can't calculate meaningful results like reaching light speed or absolute zero. They should be seen as boundary conditions that put finite limits on phenomena.
 

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Re: How do we handle infinite frames?
« Reply #6 on: 23/02/2014 23:43:01 »

 

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