Can anyone help me with Ex 4.1 in MTW?(adsbygoogle = window.adsbygoogle || []).push({});

What is a 'generic' field? My expectation is that it would comprise an Electric Field, with arbitrary direction, a Magnetic Field, also with arbitrary direction, and a radiation field (E and B of equal magnitude) , radiating in an arbitrary direction.

Trying to put this together however to get the Poynting density of energy flow and the density of energy is a bit of a mess however, so I suspect my expectation is wrong.

Moving on to the next bit of the problem, if you do define the unit vectorand velocity parameter α as shown, then a solution to this is a radiation field with E along the x axis, B along the y axis, producing a Poynting vector along the z axis. If you then translate to the rocket frame,nEXBdisappears becauseBbecomes zero, not becauseBbecomes parallel toE. I can't see howBends up parallel toE.

Can anyone help?

TerryW

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# Generic Local Electromagnetic field - MTW Ex 4.1

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