Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

Is the magnetic field propagated by photons or by virtual photons? If it is by photons, then doesn't that mean that magnets lose energy and eventually become non magnets?

share|improve this question
    
This might interest you, levitationfun.com/mfield.html It has references but no links. In a nutshell, virtual photons create the magnetic field observed from a permanent magnet, the diagram ending back to the magnet. –  anna v Mar 8 '12 at 5:59
    
More on virtual photons and magnets: physics.stackexchange.com/q/3580/2451 and physics.stackexchange.com/q/14980/2451 –  Qmechanic Mar 8 '12 at 6:06
    
Thanks everyone for the awesome links :) –  Rahul Mar 8 '12 at 11:24
add comment

2 Answers 2

up vote 2 down vote accepted

You are right, real photons always travel at the speed of light and would carry energy away from a magnet.

From a field theory point of view, all static fields, whether electric, magnetic, the weak nuclear force or the strong nuclear force can be thought of as being mediated by virtual particles. So for either electric or magnetic fields, that would be virtual photons that mediate the field. See Wikipedia for more information. Another great article explaining virtual particles is from John Baez and finally see this question and answer: What's the relation between virtual photons and electromagnetic potentials? .

share|improve this answer
    
WOW. Mind=Blown. Thanks for the reply. –  Rahul Mar 8 '12 at 11:25
add comment

A quick clarification on the second part of your question: Virtual force particles differ from real ones in that they don't dissipate any energy. It's part of that "virtual" thing!

share|improve this answer
add comment

protected by Qmechanic Aug 17 '13 at 6:58

Thank you for your interest in this question. Because it has attracted low-quality answers, posting an answer now requires 10 reputation on this site.

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.