May an electron exceed the velocity of light in a dielectric medium ?

Question

http://en.wikipedia.org/wiki/Cherenkov_effect

http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/einvel.html

yea...just to cut off all those b*** s***s, you know wich...

Answer 1

read the wiki again....the velocity that exceeds lightspeed is phase velocity......now click on phase velocity......read the little derivation that comes at the end....all matter waves have phase velocity exceeding c. yet , this does not violate special reativity since these waves do not carry any information, that is, they do not interact with matter.
we were explained this in class...i was amazed, but it is true.

so it is apt to say that the phase velocity of an electron may indeed exceed the speed of light.

Answer 2

The velocity of light in a dielectric medium is
v=c/n where c =speed in the air(or vacuum), n refraction index

n is always higher than1

the electron being a particle can not have a velocity equal or greater than c , But can have a velocity higher than c/n.
When this arrives light is emitted in the same manner that noise is emitted by a plain moving faster than the velocity of sound