Negative kinetic energy value for an electron

[clumps tim]

HI,
I have been going through dirac's paper on quantized singularities in the electromagnetic field and there he referred to a problem of negative kinetic energy of electron, what does it mean?

I am going to make a presentation on magnetic monopole next month so I need an explanatory answer

regards

 

[Khashishi]

I haven't looked up the context of the paper, but an electron can be thought of as having negative kinetic energy in the evanescent part of the wave, such as inside a barrier that an electron tunnels through. The electron is allowed to be detected in a classically forbidden position.

 

[bhobba]

I think he is referring to his hole theory:
http://quantummechanics.ucsd.edu/ph130a/130_notes/node490.html

These days its handled in QFT where the creation operator for electrons is interpreted as the annihilation operator for a positron, and conversely, without the need for negative energies:
http://en.wikipedia.org/wiki/Antiparticle

Thanks
Bill

 

[Jilang]

I haven't looked up the context of the paper, but an electron can be thought of as having negative kinetic energy in the evanescent part of the wave, such as inside a barrier that an electron tunnels through. The electron is allowed to be detected in a classically forbidden position.

I don't think you can ever detect a particle in the classically forbidden region.