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      |   |   
            | Subject: 
 | Re: Relativity Question 
 |  
            | Newsgroups: 
 | lugnet.off-topic.geek 
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            | Date: 
 | Wed, 8 Nov 2000 21:32:13 GMT 
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            | Viewed: 
 | 1191 times 
 |  |  |  
 | 
 |  | In lugnet.off-topic.geek, Dave Schuler writes: > In lugnet.off-topic.geek, Jay Jacinto writes:
 >
 > > For example:  an observer accelerating away from a stationary observer would
 > > experience the sensation of acceleration.  Conversely, the stationary  observer
 > > would experience a gravitational field generated by the Universe accelerating
 > > from the other observer.  So neither could determine which is in the
 > > accelerated inertia frame.  Thus, all motion including acceleration is
 > > relative.
 >
 >  Well, thanks for throwing a monkey wrench into it for me.  How do the
 > famous de-synchronized clocks fit into this?  Obviously one of them slowed
 > down relative to the other.  Do we infer that the ground-based clock
 > decelerated sufficiently to speed up time's local passage?  I thought I had
 > a handle on this, but now I see I'm missing something.
 
 Acceleration is bad ju-ju, since it isn't accounted for in special relativity.
 It's only in General Relativity that we get gravity thrown into the mix, and
 that's taught in grad school.  However, from a strictly special relativistic
 POV the observer that is actually moving measures time slower than a stationary
 observer as determined by the Lorentz transform.  In this example there are
 only two inertia frames, the rest of the universe is ignored.
 
 > > Also the doppler shift measured by each observer will be the same, all
 > > acceleration does is add an additional term as determined by the Lorentz
 > > transformation.
 
 I think I goofed here concerning the additional term from acceleration.  The
 frequency of light emitted is determined only by *instantaneously* velocity and
 the wavelength of light.
 
 >  Hmm.  This is the part that always messes me up.  So if there is a distant
 > star whose light we see as red-shifted, and X is standing on Earth, while Y
 > takes off at .9c toward the distant star, will both X and Y perceive the
 > same red-shift?
 >
 >     Dave!
 
 Yep, if we consider at least one of the objects to be at "rest." The actual
 factor that determines the doppler shift is the following:
 
 sqrt((1 + ß)/(1 - ß))
 
 which is the classical doppler shift with some simplication.
 
 ß = v/c
 v = velocity
 
 I feel like I'm digging a very deep hole for myself with all this.
 
 Thanks
 Jay Jacinto
 
 |  |  |  
 
 Message is in Reply To:
 
  |  |  | Re: Relativity Question 
 | 
 |  | (...) Well, thanks for throwing a monkey wrench into it for me. How do the famous de-synchronized clocks fit into this? Obviously one of them slowed down relative to the other. Do we infer that the ground-based clock decelerated sufficiently to (...)   (25 years ago, 8-Nov-00, to lugnet.off-topic.geek) 
 |  34 Messages in This Thread:
 
              
                
                      
                 
           
        
      
      
         
               
     
 
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