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Originally Posted by James Putnam  I think that challenging the theory of time dilation should be easy to accomplish... |
Have at it. That's what people have been doing for a century since Einstein's paper was first published.
You know what? It's withstood every test thrown at it.
I point you now toward the Hafele-Keating experiment.
Hafele-Keating experiment - Wikipedia, the free encyclopedia
Here is a nice and quick video summary of that experiment:
A blogger whom I follow, who is very well versed in the physics of time (has a few post docs even, and literally builds atomic clocks as part of his job), wrote a post about this back in January, showing how even a trip in your car or van results in time dilation, and you can learn A LOT by reading that. Here is the link:
Swans on Tea The Relativistic Van
Here are a few additional studies supporting the idea:
Haefele and Keating, Nature 227 (1970), pg 270 (Proposal); Science Vol. 177 pg 166--170 (1972) (Experiment).
They flew atomic clocks on commercial airliners around the world in both directions, and compared the time elapsed on the airborne clocks with the time elapsed on an earthbound clock (USNO). Their eastbound clock lost 59 ns on the USNO clock; their westbound clock gained 273 ns; these agree with GR predictions to well within their experimental resolution and uncertainties (which total about 25 ns).
Vessot et al, "A Test of the Equivalence Principle Using a Space-borne Clock", Gel. Rel. Grav., 10, (1979) 181-204; "Test of Relativistic Gravitation with a Space borne Hydrogen Maser", Phys. Rev. Lett. 45 2081-2084.
They flew a hydrogen maser in a Scout rocket up into space and back (not recovered). Gravitational effects are important, as are the velocity effects of SR.
C. Alley, "Proper Time Experiments in Gravitational Fields with Atomic Clocks, Aircraft, and Laser Light Pulses," in Quantum Optics, Experimental Gravity, and Measurement Theory, eds. Pierre Meystre and Marlan O. Scully, Proceedings Conf. Bad Windsheim 1981, 1983 Plenum Press New York, ISBN 0-306-41354-X, p363-427.
They flew atomic clocks in airplanes which remained localized over Chesapeake Bay, and also which flew to Greenland and back.
Bailey et al., "Measurements of relativistic time dilatation for positive and negative muons in a circular orbit," Nature 268 (July 28, 1977) pg 301; Nuclear Physics B 150 pg 1-79 (1979).
They stored muons in a storage ring and measured their lifetime. When combined with measurements of the muon lifetime at rest this becomes a highly-relativistic twin scenario (v ~ 0.9994 c), for which the stored muons are the traveling twin and return to a given point in the lab every few microseconds.
Muon lifetime at rest:Meyer et al., Physical Review 132, pg 2693; Balandin et al. JETP 40, pg 811 (1974); Bardin et al. Physics Letters 137B, pg 135 (1984). Also a test of the clock hypotheses (below).
The Clock Hypothesis
The clock hypothesis states that the tick rate of a clock when measured in an inertial frame depends only upon its velocity relative to that frame, and is independent of its acceleration or higher derivatives. The experiment of Bailey et al referenced above stored muons in a magnetic storage ring and measured their lifetime. While being stored in the ring they were subject to a proper acceleration of approximately 1018 g (1 g = 9.8 m/s2). The observed agreement between the lifetime of the stored muons with that of muons with the same energy moving inertially confirms the clock hypothesis for accelerations of that magnitude.
Sherwin, "Some Recent Experimental Tests of the 'Clock Paradox'", Phys. Rev. 129 no. 1 (1960), p17.
He discusses some Moessbauer experiments that show that the rate of a clock is independent of acceleration (~1016 g) and depends only upon velocity.
From: Experimental Basis of Special Relativity
So, I showed you my hand.
What cards are you holding?
