On Jan 22, 2006, at 5:05 AM, Stephen A. Lawrence wrote:
Acceleration doesn't affect clocks. That's been verified (can't
cite references, sorry). A clock in a centrifuge slows only as a
result of the speed at which it's traveling, not as a result of the
centripetal force.
This can not be consistent with relativity, for the reasons I repeat
below. These issues demonstrate the usefulness of Jefimenko's work.
His physics is developed strictly on the basis of retardation - the
affects of photon travel delays upon the observer. He shows that the
effects of such delays depend on the type of clock being examined,
which leads to some potential conflicts with the type SR you are
applying. He also derives the laws of electromagnetics, showing the
magnetic field is the result of retardation upon observations of the
Coulomb field. The magnetic field can not both exist as an
independent entity and as an observational effect, otherwise magnetic
field intensities should be double that observed.
While effects based on retardation are of great interest for
predicting observational effects, like apparent clock rate changes
and magnetic field strength, they can not possibly explain the twins
paradox experiment. When the clocks return to be side by side in the
same reference frame, if there is any difference in their times, then
those differences have to be due to acceleration, or by Einstein's
principle of relativity, due to gravity. They can not be due to
retardation effects because there are none.
THE ONE DIMENSIONAL MODEL
The issues are simplified by looking at things one dimensionally, and
such a simplified system is sufficient to examine the critical
issues. The difficult math seems to me to disappear in a flash! 8^)
No longer are fancy transforms and distance functions required.
Further, we can look at each flash from earth as a single photon.
As the traveler departs in a straight line away from the earth
transmission point, and distance from earth gets greater, the photons
arrive further apart in time, and red shifted for the same reason,
the wave peaks arrive slower, thus time back on earth appears to the
traveler to slow down. However, no matter what kinds of
accelerations the traveler has experienced or is experiencing, he
keeps receiving his regular periodic set of photons from earth. The
only thing that changes are the time increments sensed by the
traveler between photons, and their colors. No matter where he is or
how far he goes or how he accelerates, assuming a fast rate of photon
transmission from earth, there are always photons in route from earth
to the traveler. As the traveler turns about, and returns, the rate
he absorbs those photons increases, and he sees a blue shift as well,
for the same reason, i.e. the wave peaks arrive faster. The earth
increments its clock each time a photon is transmitted. The traveler
can increment his on board "earth clock" each time he receives a
photon. He can use a similar clock to the earth clock to keep track
of his local time.
As the traveler closes the distance to earth on the return trip,
fewer photons are in flight with passing time. Assuming the
traveler's on board clock was not affected by his acceleration, his
"earth time" clock and local clock will come back in
synchronization. Further, his earth time clock and earth's clock
will be in perfect synchronization upon arrival. If not, the number
of photons sent and the number received can not match, which is
nonsense. The only other way for the traveler's clock to not agree
with the earth clock, or his own "earth time" clock for that matter,
is for the traveler's clock to have been affected by the acceleration.
If this makes any sense, then faster than light travel can make sense
as well, assuming the traveler has an infinite Isp drive, like a ZPE
drive. As the traveler exceeds the speed of light, he simply does
not see any photons from earth. This does not mean he is traveling
backwards in time. It only means his communication with earth is cut
off (unless of course he has some spooky action at a distance
communication device.) When he the traveler turns around, he
eventually starts receiving the photons again, but very much blue
shifted. When traveling faster than light relative to earth, his
earth clock merely stops, it doesn't run backwards. His own local
clock, however, keeps on ticking. Again, without some change in the
traveler's clock due to acceleration, all the clocks must be in
synchronization upon his return.
EN-GAUGING
Clock rates in a gravitational field are affected by the
gravitational potential, not the local gravitational field strength.
The gravitational potential cannot change without the gravitational
strength changing. One dimensionally speaking, anything which is a
function of the gravitational potential is a function of the
gravitational field plus an arbitrary constant of integration. No
matter how you cut it, clock rate is a function of gravitational
field. If the effects of the gravitational field differ from the
effects of acceleration (this difference at any point) then
Einstein's fundamental assumption for GR is violated and GR
disappears in a flash! 8^)
I also have to question the validity of the tangential straight rod
approach you use. I could be missing something, but it doesn't seem
to account for how we would see the clock advance as it passes behind
the earth in the opposite direction.
Horace Heffner
