I'm a radio engineer trying to understand the world.

Reading about SR and GR I have the concept that the force due to
gravity is not actually a force but is actually the curvature of space
time and that objects in "free fall" simply follow the curve of
space-time. OK no problem.

What about the forces due to the electric and magnetic field. Are
these also curvatures of space-time?

I don't see anything written about that but my guess is no because not
all objects are effected by the EM field. OK. So then what does cause
the forces on objects due to the E and M fields?

thanks

Mark

"Mark" wrote in message
ups.com...
I'm a radio engineer trying to understand the world.

Reading about SR and GR I have the concept that the force due to
gravity is not actually a force but is actually the curvature of space
time and that objects in "free fall" simply follow the curve of
space-time. OK no problem.

What about the forces due to the electric and magnetic field. Are
these also curvatures of space-time?

Depends on exactly how you define spacetime. You would think that just
playing around with magnets and charged ballons, that the EM forces
could be modeled as spacetime curvature also. However, this requires
that spacetime be defined as a relativistic medium where "vacuum"
polarization is taken to tree level. Not many people want to go
there... yet. ;-)

I don't see anything written about that but my guess is no because not
all objects are effected by the EM field. OK. So then what does
cause
the forces on objects due to the E and M fields?

Currently it is explained on a fundamental level by the exchange of
photons.

FrediFizzx

Quantum Vacuum Charge papers;
http://www.vacuum-physics.com/QVC/qu...uum_charge.pdf
or postscript
http://www.vacuum-physics.com/QVC/qu...cuum_charge.ps
http://www.arxiv.org/abs/physics/0601110
http://www.vacuum-physics.com