Re: Retarded propagation of magnetic field leads to contradiction

From: Myxococcus xanthus (mold-guardian_at_comcast.net)
Date: 07/30/04 

Date: 30 Jul 2004 04:03:21 -0700

Eugene <eugenev@synopsys.com> wrote in message news:<4109EF69.3030503@synopsys.com>...
> Consider simple experiment:
>
> A magnet and a wire loop are separated by the distance R.
> If both of them are at rest, there is no current in the loop.
>
> If the magnet starts to move then (we assume that the
> magnetic field propagates with the speed of light) the current
> starts to flow in the loop only after time R/c
>
> If the magnet stands still, but the loop moves and
> crosses the magnetic lines, the current starts to flow
> immediately.
>
> As from the relativity principle both these situations should
> be equivalent, we got a contradiction.
>
> SOLUTION OF THIS PARADOX: Magnetic field propagates
> instantaneously.
>
> This solution cannot be rejected by invoking the causality
> paradox (i.e., apply the Lorentz transformations and show that
> there is a moving frame of reference in which current starts to
> flow BEFORE the magnet moves) This is because the
> Lorentz transformations are not exactly applicable to this system:
> One should take into account their dependence on interaction.
> Then, the shift of the magnet and the onset of the current become
> simultaneous in ALL reference frames.

Consider simple experiment:
 
A tuning fork and you are separated by the distance R. If both the
tuning fork and you are at rest, you hear a pure A-440 note.

If the tuning fork starts to move towards you then (we assume that the
sound propagates with the speed v_s) you hear the doppler-shifted,
slightly sharp A only after time R/v_s
 
If the tuning fork stands still, but you start to walk towards the
fork, you hear a doppler-shifted note immediately.
 
As from your misunderstanding of the relativity principle both these
situations should be equivalent, we got a contradiction.
 
NON-SOLUTION OF THIS NON-PARADOX: Sound propagates instantaneously.

Duh.

Myxococcus xanthus

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