Update from CERN: The Higgs and Nothing More

Title: Update from CERN: The Higgs and Nothing More
Speaker: Glenn Starkman, PhD
Date: May 1, 2013
Location: campus, Case Western Reserve University

[PoojaDeshpande]

This was awesome.
Heartfelt thanks to the presenter...

[ZombieLincoln]

Actually the "m" in E=mc^2 is referring to a rest mass, which excludes photons, which are massless and never at rest.

The actual equation is E = sqrt((mc^2)^2+(pc)^2), which for photons (m=0) becomes E=pc, where p is the momentum (which photons have).

[ccvincent]

So how does momentum (mass x velocity) = other than 0 when mass = 0? Lets say m = E/c^2, if that is not a misconstruction. What possible value can E have so that E/c^2 = 0?
It seems that photons (for instance) are 'required' to be "massless" for some theoretical reasons, and it happens to be a convenient figure of speech to refer to them as such. It ain't necessarily so tho, and it is not possible to verify it experimentally - as far as I can understand.

[ccvincent]

If m = 0, then E = 0 - according to E = m(c^2).
So.. How can massless entities have influence upon anything?