As a non-physicist librarian, I thought it was funny enough when they said, “See that physicist crossing the road?” I’m glad it proved more meaningful than that.
Clifford, the more I think about that elegant paper Steve linked above, the more I think that this would make an excellent subject for a full blown blog post, if not by you then perhaps by someone more interested in condensed matter or solid state quantum mechanics. If nothing appears for a couple of months, I’ll write one up myself.
Here here on the paper and calc! When I was in grad school, R(0,1) was assigned as a problem on the PhD qualifying exam some years before, and so was studied by students. I’m adding a link back to here on the page I wrote up complaining about the uselessness of the calculation.
Seeing the Brillouin zone problem with the elegant discrete Laplacian solution makes me feel better about the problem in general, but I still think that the R(0,1) problem is a stupid one to put on a qualifier. Uh, I guess I should mention that I got my MS in physics by passing the PhD qualifier but didn’t go on to write a thesis.
It seems that some of my Mathematica code got “eaten” by your commenting system, but luckily the code that got through can still compute R[2,1] correctly.
I believe in the 60s we called this game “mindtag.” More points were awarded for tagging a person (accomplished by completely derailing their line of thinking or reasoning particularly when they were speaking or lecturing) who was not under the influence of whatever (usually in academic or professional work settings), and points were deducted for taking unfair advantage of friends who were too high to track any thoughts past the first verb phrase. I see it has now under gone a comix-reduction reaction when combined with the bizarre (but oddly entertaining) cult-film DeathRace 2000.
Just noticed that 4 years ago to the day I did a post about #LEGO and #LittleBits, and coincidentally today we tinkered with them for the first time in a while…
Hard to express my feelings about this news. Quincy Jones is a massive part of the foundations of my formative years (in so much music across genres and media). Inevitable passing, of course, but no less sad… Thanks for the music and inspiration Quincy!
In the “American Dad” mode of my regular code-switching routine, I’m on little league parent duty. Big final Sunday game. Dodgers fielding… #littleleague
Just noticed that 4 years ago to the day I did a post about #LEGO and #LittleBits, and coincidentally today we tinkered with them for the first time in a while…
Hard to express my feelings about this news. Quincy Jones is a massive part of the foundations of my formative years (in so much music across genres and media). Inevitable passing, of course, but no less sad… Thanks for the music and inspiration Quincy!
In the “American Dad” mode of my regular code-switching routine, I’m on little league parent duty. Big final Sunday game. Dodgers fielding… #littleleague
Carl, it is indeed interesting. I cannot promise a blog post, however. Too many things on my plate at present.
-cvj
As a non-physicist librarian, I thought it was funny enough when they said, “See that physicist crossing the road?” I’m glad it proved more meaningful than that.
Clifford, the more I think about that elegant paper Steve linked above, the more I think that this would make an excellent subject for a full blown blog post, if not by you then perhaps by someone more interested in condensed matter or solid state quantum mechanics. If nothing appears for a couple of months, I’ll write one up myself.
Here here on the paper and calc! When I was in grad school, R(0,1) was assigned as a problem on the PhD qualifying exam some years before, and so was studied by students. I’m adding a link back to here on the page I wrote up complaining about the uselessness of the calculation.
Seeing the Brillouin zone problem with the elegant discrete Laplacian solution makes me feel better about the problem in general, but I still think that the R(0,1) problem is a stupid one to put on a qualifier. Uh, I guess I should mention that I got my MS in physics by passing the PhD qualifier but didn’t go on to write a thesis.
Hi Steve,
thanks for the reference – that’s a cool paper!
Happy New Year!
Stefan
Steve…. maybe use LaTeX… See sidebar.
Cheers,
-cvj
It seems that some of my Mathematica code got “eaten” by your commenting system, but luckily the code that got through can still compute R[2,1] correctly.
Ha HA! Excellent! And you did not get hit by a truck either!
Thanks…
-cvj
Whoosh!! Off I went on the internet to find this: http://arxiv.org/PS_cache/cond-mat/pdf/9909/9909120v4.pdf. Equation (32) is what you need.
Whoosh!! Out came my trusty Mathematica:
R[m_,m_]/;m>=2:=-(((-1+2 (-1+m)) R[-2+m,-2+m])/(1+2 (-1+m)))+(4 (-1+m) R[-1+m,-1+m])/(1+2 (-1+m));
R[m1_,m_]/;m1==m+1&&m>=1:=2R[m,m]-R[m,m-1];
R[m_,0]/;m>=2:=-R[-2+m,0]+4 R[-1+m,0]-2 R[-1+m,1];
R[m_,p_]/;0=2:=-R[-2+m,p]-R[-1+m,-1+p]+4 R[-1+m,p]-R[-1+m,1+p];
R[0,0]=0;
R[1,0]=1/2;
R[1,1]=2/\[Pi];
whence
In[8]:= R[2,1]
Out[8]= -(1/2)+4/\[Pi]
How sad is that?
I believe in the 60s we called this game “mindtag.” More points were awarded for tagging a person (accomplished by completely derailing their line of thinking or reasoning particularly when they were speaking or lecturing) who was not under the influence of whatever (usually in academic or professional work settings), and points were deducted for taking unfair advantage of friends who were too high to track any thoughts past the first verb phrase. I see it has now under gone a comix-reduction reaction when combined with the bizarre (but oddly entertaining) cult-film DeathRace 2000.