224 reputation
16
bio website
location Boulder, CO
age
visits member for 3 years, 7 months
seen May 20 at 17:39

I'm a physics graduate student at UC Boulder


Mar
28
awarded  Scholar
Mar
28
accepted Spin Liquid in a band insulator?
Mar
28
awarded  Yearling
Mar
27
awarded  Student
Mar
27
asked Spin Liquid in a band insulator?
Sep
4
awarded  Critic
Jun
19
comment Why can't a rope be pulled completely straight?
$\cos(\theta)$ does not go to zero as $\theta$ goes to zero, it goes to $1$.
May
20
revised A Question From Jackson Electrodynamics
formatting the equation
May
19
answered A Question From Jackson Electrodynamics
May
19
suggested suggested edit on A Question From Jackson Electrodynamics
May
19
comment What is negative about negative energy states in the Dirac equation?
If you go back to the post he references, it is a bit more clear that he is mixing and matching the two pictures (electrons/holes, positron/electron), instead of keeping them separate.
May
19
comment What is negative about negative energy states in the Dirac equation?
"Holes in the sea are positive-energy positrons, equivalent to the action of the positron creation operator on the vacuum." pretty much, just make sure the two pictures (negative/positive energy electrons aka. holes/electrons and positrons/electrons) are kept very separate in your mind.
May
18
answered What is negative about negative energy states in the Dirac equation?
Jul
6
comment Why aren't there compression waves in electromagnetic fields?
Something to keep in mind is that longitudinal waves are actually possible in EM, however they require a medium in which to propagate (you can't do this in a vacuum). Typically they show up in waveguides in a dielectric.
Jul
6
answered Is travel to the distant future possible without massive energy expenditure?
Jul
6
awarded  Supporter
Jul
6
awarded  Editor
Jul
6
revised Why aren't there compression waves in electromagnetic fields?
Clarified a couple of sentences, changed some dates to be more accurate.
Jul
6
answered Why aren't there compression waves in electromagnetic fields?
Jul
4
awarded  Teacher