Problem deriving failure of simultaneity at a distance

AI Thread Summary
The discussion centers on deriving the failure of simultaneity at a distance using the Lorentz transformation equations. The user struggles with the algebra involved in demonstrating that two events perceived as simultaneous in one reference frame are not simultaneous in another. They also question the necessity of time dilation in the context of the Michelson-Morley experiment, suggesting that spatial Lorentz contraction alone could explain the null result. Clarification is provided that the second equation of the Lorentz transformation must be used, highlighting that the events are simultaneous in one frame but not in another. Understanding these concepts is crucial for grasping the implications of relativity on time and space.
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Problem deriving "failure of simultaneity at a distance"

Homework Statement



I'm trying to derive the failure of simultaneity at a distance from the spatial part of the Lorentz transformation. In his treatment of the subject, Feynman glosses over the algebra/derivation and produces the formula:

simult-feynman_zps7e921a89.png


I tried to start with the first equation of the Lorentz transformation and arrive at the difference in simultaneous time. As seen from my work below, I'm not having much luck. Where is my math incorrect?

On a related note, in reading about the Michelson-Morley experiment, it appears that spatial Lorentz contraction completely accounts for the null result. Why, then, is the time dilation necessary? Wouldn't that double-count the difference in perceived time and position between the observer in the stationary and moving reference frames?

Homework Equations



The Lorentz contraction, shown above

The Attempt at a Solution



simult-me_zps2a395d8c.png
 
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You need to use the second equation of the Lorentz transformation, and recognize that in the S frame of reference, t1 = t2. That is, as reckoned from the S frame of reference, two events occur simultaneously (i.e., at t1=t2=t) at x1 and x2. As reckoned from the S' frame of reference (i.e., using a set of clocks synchronized in the S' frame of reference), the two events are observed to not occur simultaneously.
 
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