starship-design: Re: I know this is off the subject but...

[TLG.van.der.Linden@tip.nl (Timothy van der Linden)]

Steve wrote:

>Maxwell's equations can be slightly modified to account for monopoles;
>changing a zero to a constant in the equation that describes magnetic
>flux would deal with the monopole case.

I never really liked the Maxwell approach to magnetics. Einstein's approach
(relativistic velocity addition) seems to be more fundamental and gives more
insight. I would not know how to incorporate monopoles into the latter
theory, unless space is warped in strange ways (like anti-gravity).

>However, since no one has ever observed a monopole (yet) it's believed
>that the current formulation of Maxwell's equations is correct.

Just there is not a current observation of repulsive-gravity.

>Actually, it's fairly easy to detect a monopole.  The detector I heard
>of is simply a loop of superconducting material.  A monopole passing
>through the loop would induce a current flow that would remain in the
>loop after the passage of the monpole, unlike a dipole which after
>passing through the loop would leave no net current flow.

Yes, that would work, except that it may be difficult to have 100% symmetry
doing it like this: Suppose you've a normal magnet, how do you know that you
have moved it an exact equal distance from "in front of" to "at the back of"
the superconductor?
To be able to do this you should be able to figure out where the "center of
magnetivity" of the magnet is.

To avoid this problem, you may turn around the monopole in the neighbourhood
of the superconductor. After a 360 degree turn, the current in the
superconductor before and after should be the same.

(Of course if you have a big magnetic monopole, the crude method will give
results that speak for themselves)

Timothy