From: heathjohn2@gmail.com   
      
   I asked this question in an electrical   
   engineering group. The room went so   
   quiet you could hear a pin drop. Maybe   
   physics research group is a more   
   appropriate place to pose this question.   
   I will copy and paste the original question.   
      
   This one has been on my bucket list for   
   a while. How to make a Lorentz contraction   
   voltage measurement ? It is my hope by   
   putting some of my failed attempts on the   
   table that others on the list could breath   
   new life into this problem.  An out of the   
   box approach from different shoes that   
   would not occur to myself.   
      
   First of all what is a Lorentz contraction   
   voltage measurement. If one probe is grounded   
   and the other toughing a magnet the voltage   
   should be extremely negative , 100 KV or   
   so. Not just a magnet but a copper wire   
   carrying 10 amps should also have effective   
   electron contraction leading to an extreme   
   negative voltage around the wire. However it   
   can not be measured with a conventional meter   
   as the meter leads are entering the magnetic   
   frame of reference therefore it cancels out.   
   Its a no win.   
      
   Failed attempts on my part. Use a magnetic   
   probe. Close but no cigar as a magnetic probe   
    , current probe , makes a distinction between   
   north and south poles. Lorentz electron length   
   contraction makes no such distinction as both   
   north and south poles have effective length   
   contraction therefore negative charge. Same   
   is true of current in a wire regardless of   
   current direction.   
      
   Build a mechanical mono pole south in and   
   another north in with flat magnets then   
   measure the voltage between both opposite   
   mono poles from the inside. Can not remember   
   why I thought that would work. Suffice to   
   say it did not work.   
      
   Not tried yet. A gold leaf jar. Replace the   
   gold leaf with two pieces of iron then connect   
   the new iron leaf jar with thin bars of iron   
   to make contact with the magnet. An iron leaf   
   jar would not make a distinction between north   
   or south poles of a magnet as in both cases the   
   iron leafs would separate a little. However   
   would this be measuring a Coulomb force caused   
   by Lorentz electron contraction or just a dirty   
   trick to lose the distinction between a north   
   and south poles?   
      
   One more. Sky charge. Sky charge is about   
   100 volts per meter or 200 volts from head to   
   toe. Like the Lorentz electron contraction   
   this is a voltage that can not be measured   
   with a conventional meter. The solution is a   
   voltage field meter. It consist of a fan ,   
   sheet of copper and a hole on top. If there   
   is a fluctuating voltage at the copper plate   
   that equals the frequency of the fan blades   
   than there is an electric field. Maybe this   
   would work?   
      
   Any thoughts on this would be welcome.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)