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Twin Paradox - Clock Paradox

                                       (Also called Twins Paradox)

There is no twin paradox or clock paradox.

The reason there is no paradox is that clocks in different inertial
frames actually do run at different rates, leading to an obvious
difference in their registered time upon reuniting.  And yes, the 
effective (experimental) equivalence of inertial frames is preserved, 
in complete agreement with Einstein's special relativity.


Regarding A and B of different inertial frames, taking measure of
each other as they pass by each other, here is the typical exchange
between a professor (or author) and the student (or reader):


  Professor:

  Person A will regard person B's clock to be slower and person B's
  spaceship to be shorter, and person B will regard A's clock to
  be slower and A's spaceship to be shorter.

  Student:

  What is the truth of the matter?

  Professor:

  There is no truth of the matter.  One person's reality is as
  valid as the other's.

  Student:

  Then why does one person age more than the other over the course
  of a round trip between them?

  Professor:

  It is the party that changes inertial frames that will age the 
  least over the course of the round trip.  We can illustrate
  this with a spacetime diagram.  See right here - the party who
  changes frames suddenly has overlooked a stretch of time passage
  for the party who did not change frames. 


Imagine that.

This is the standard "jump in time" argument.   Such as in Wikipedia.

And it is utter nonsense.  

Einstein's clock synchronization (identically spacetime) cannot be utilized
to explain the "missing" time of the twin paradox.  Such clock synchronization
is useful only when no party changes frames.  The fatal mistake made by
examiners of the "paradox" (a paradox strictly of their own making) is to
employ Einstein's clock synchronization (identically spacetime) to the 
"paradox".  It is responsible for the notorious "jump in time".

Simply for starters, it is impossible for an actual physical difference 
in the readings of reunited clocks to be due to anyone's misperception 
or overlooking.  

Beyond that, there is no possibility of such a misperception or overlooking.
It is a trivial matter to show that an observed assymetry in time-keeping 
differences builds incrementally beginning at the moment of an inertial
change for either party.

The purveyors of these absurd diagrams typically fail to acknowledge a 
transfer of clock reading from an outbound traveler to an inbound traveler.
Such transfer is requisite for any study involving special relativity,
otherwise acceleration is involved.  We cannot use acceleration to explain 
the differential:  No acceleration is incorporated in Einstein's derivation, 
yet the time differential arises from his derivation, just as does the
mutuality of measured clock and length distortion across inertial frames.
You cannot derive one without the other.  By not acknowledging
a transfer of information, these purveyor's slip in a claim that an inertial 
force is somehow involved.

Just as clock information is exchanged across inertial frames to 
effect the observation of mutually measured clock rate slowing, so too 
does the transfer of clock reading from an outbound traveler to an 
inbound traveler effect an observed incremental increase 
in clock rate differences.

This is not to say that spacetime diagrams incorporate the effects of 
acceleration.  Rather they incorporate the purveyor's own deduction of what 
the time differential will be upon the reuniting of clocks 
(unconsciously utilizing the universal frame).  That deduction is then 
misconstrued by the purveyor as a misperception on the part of the party 
changing frames, at the moment of changing frames (due to the purveyor's 
ignorance of the actual observation paradigm).  Such "misperception" is then 
purportedly responsible for effecting a physical difference in the readings 
of the two clocks involved.  In short, it is ludricrous twice over.

In Spacetime and Electromagnetism, Lucas and Hodgson attempt to 
resolve the twin paradox by way of the just mentioned "jump in time" 
spacetime diagram.  After seven pages of contemplation, they admit 
no resolution, questioning the the arbitrariness of the diagram which 
"begs the question in favor of the earth-bound twin".  They then 
devote another nine pages to the topic of the twin paradox, and they 
make no claim of resolution that we could detect.

Again -  there is no paradox,  and there is no jump in time, either
real or as measured by any traveler.  A clear presentation of relativity,
utilizing the absolute speed of light through an absolute frame of reference,
both precludes any such paradox and subsumes Einstein's treatment.


For a five page commentary on the matter, with 
an included  table of an actual analysis, see:

twinparadox.pdf



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