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Joined: 6/1/2005
Msg: 30
The lightyear-long rod problemPage 5 of 5    (1, 2, 3, 4, 5)
I suggest people read up on the Ehrenfest Paradox since it lead physicists to look at the relationship between relativity and elasticity. The upshot of it all is that a completely rigid rod cannot exist if relativity is true.

Of course that leads us to another paradox. In Einstein's 1905 paper on relativity (On the Electrodynamics of Moving Bodies) he was very clear about what constituted a reference frame (which was instrumental to the development of SR).

"The theory to be developed is based--like all electrodynamics--on the kinematics of the rigid body, since the assertions of any such theory have to do with the relationships between rigid bodies (systems of co-ordinates), clocks, and electromagnetic processes. Insufficient consideration of this circumstance lies at the root of the difficulties which the electrodynamics of moving bodies at present encounters."

"Let us in 'stationary' space take two systems of co-ordinates, i.e. two systems, each of three rigid material lines, perpendicular to one another, and issuing from a point. Let the axes of X of the two systems coincide, and their axes of Y and Z respectively be parallel. Let each system be provided with a rigid measuring-rod and a number of clocks, and let the two measuring-rods, and likewise all the clocks of the two systems, be in all respects alike. "

Einstein's whole theory is built upon the use of rigid rods which his theory says cannot exist!
Joined: 6/1/2005
Msg: 33
The lightyear-long rod problem
Posted: 11/30/2009 10:26:27 AM

If in the LHC a particle interacts with another does that information get transmitted to the other side of that particle in a zero time frame. If there is nothing to compress?
Even though the two particles don't actually touch, their interactions pass on that information from 1 side of the field to another, is this passing on, from one side of the particle to another in a zero time frame or is there an internal compression of the particle?

Obviously it is above your comprehension so the question goes out to anyone else.

Particles have zero volume so I don't know that it makes any sense to talk about different sides of particles.
Joined: 3/16/2009
Msg: 35
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The lightyear-long rod problem
Posted: 12/4/2009 7:46:53 AM
For the missile, it's not the air that's moving, it's the object - the missile. The missile creates a shock wave that propagates through the air at the speed of sound. You'll never hear the missile coming as the shock wave (sonic boom) will arrive sometime after the missile!
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