Recent content by gn0m0n

I think that's what the poster meant. Extensions like the one to which Joris posted a link allow even finer control over which elements on the page are printed. That should be great as long as you're not printing too many threads or threads with too many posts (just b/c it would become tedious...

Joris, thanks, something like that would help at least for threads that aren't too many pages.

Found this thread because I was wondering the same thing. According to an old thread from 2009, there used to be a print-friendly option but I guess not since the major UI overhaul. Overall the new UI is a huge improvement. Hopefully that feature will be reinstated eventually.

If gauge symmetries are really just redundancies in our description accounting for nonphysical degrees of freedom, then how does one explain the deep and powerful fact that if one begins with, say, just fermions and no gauge field in one's theory (and no interactions & essentially no dynamics)...

Hi, yes, it was taking that integral that I was having trouble with. Thanks.

Nevermind - I got it.

I still don't see how to take these integrals. I've tried it a few ways.

Homework Statement This is from an old exam I'm studying from. It goes: "A particle of mass m is traveling in one dimension under the influence of a potential V = -Fx where F is a known constant. Find the energy spectrum and wavefunctions. Hint: You may want to work in momentum...

Sorry that looks kind of rough, I'm no expert at TeX.

Homework Statement Prove the magnitude R of the position vector \vec{R} for the center of mass from an arbitrary point of origin is given by the equation M^{2}R^{2} = M\sum{m_{i}r^{2}_{i} - \frac{1}{2}\sum{m_{i}m_{j}r_{ij}^{2} Homework Equations \vec{R} = \frac{1}{M}...

I haven't really read these yet but: http://www.phys.psu.edu/~cteq/misc/Feyn/ http://library.wolfram.com/infocenter/BySubject/Mathematica/ApplicationPackages/AdditionalApps/FeynCalc/ This is old and it requires a postscript viewer such as Ghostview but it looks good...

I should have had a denominator of m^2/s^2 in the log there, or subtracted a log|^2/s^2|. Anyway, that is not the problem...

Hi, I am trying to calculate a double integral, in Mathematica it could be denoted Integrate[(x*y)/(x*y-m2/s2),{x,0,1},{y,0,1-x}] That is, \int\int\frac{xy}{(xy-m^{2}/s^{2})}dydx with boundaries y=0,y=1-x and x=0,x=1. m and s are constants, of course. Now, I get some fairly...

I'm still having some trouble getting this to come out right so if anyone has any other thoughts, please share! I ended up with -(1/2)g^2 instead of -2g^2 ! So close! I am wondering if I made proper assumptions, e.g., in this case, p1=-p2=-p3=p4, right? And E1=E3, E2=E4? Also the helicity...

Cool, thanks. I just want to understand ANY way to get through it right now, I'm not too concerned if it's not pretty ;) So are we sort of looking at the two gamma_mu's and acting the same as if they were right next to each other, i.e., summing over like indices (subtracting where...