928 reputation
512
bio website chemie.uni-hamburg.de/ac/AKs/…
location Hamburg
age 54
visits member for 4 years, 5 months
seen May 24 at 17:16
knot theory dilettant!

May
20
comment Fusion category R-symbols diagonal even when multiplicity present?
Also, regarding 3.3. of Galindo: Of course they are, but can you get BOTH Schur and braiding to be diagonal? (I assume the unitary case by default.)
May
20
comment Fusion category R-symbols diagonal even when multiplicity present?
@Matthew - I know the Ostrik paper. But the data is OK - the Verlinde matrix V is symmetric, has V=V+ and VV=I, and it exists a diagonal matrix W such that (VW)^3=I. What is NOT the case is that W is cyclotomic. So F is not modular but still braided. Or do I confuse the many many fusion category bynames again?
May
19
asked Fusion category R-symbols diagonal even when multiplicity present?
May
14
comment Not especially famous, long-open problems which anyone can understand
Arguably, the brick violates the "outside mathematician" condition. I even tried to convince some crank (may one say this word here? :-) not to waste as many of his lifetime to the problem as I did.
May
12
comment Physics that needs “new” math
Calculus by Newton, how could I forget that? :-) Yes, that's the "canonical" answer (and my question can as well be closed).
May
11
asked Physics that needs “new” math
May
5
comment “Prime” fusion rings
After reading Höhns webpage on modular categories etc. - yes, the concept "prime" seems to be known.
May
5
comment Non Lie-group ribbon categories
That was a very detailed comment. Most of the papers I already have DLed (and I already suspected the "Haagerup" to be an example - maybe I somewhen compute the skein relation just for fun :-). THX and upped.
May
5
accepted Non Lie-group ribbon categories
May
4
asked Non Lie-group ribbon categories
May
2
answered Polynomial invariants for unoriented links
Apr
26
accepted “Diagonalizing” an associative algebra
Apr
22
asked “Diagonalizing” an associative algebra
Apr
7
awarded  Nice Question
Apr
1
revised “Epicycles” (Ptolemy style) in math theory?
Some extension
Mar
31
comment “Epicycles” (Ptolemy style) in math theory?
@David: A hint I'm German :-) (Some theory within math, singular...)
Mar
31
comment “Epicycles” (Ptolemy style) in math theory?
Upped this one because I can understand it most easily (and, as Todd said, Ptolemy was just an example by me - which I used because "epicycles" nowadays is used figuratively).
Mar
31
accepted “Epicycles” (Ptolemy style) in math theory?
Mar
30
asked “Epicycles” (Ptolemy style) in math theory?
Feb
20
revised Maximum symmetry of generic 6j symbols?
Minor corrections