800 reputation
411
bio website chemie.uni-hamburg.de/ac/AKs/…
location Hamburg
age 53
visits member for 4 years
seen 1 hour ago
knot theory dilettant!

22h
asked “Generators” for fusion rings
Dec
2
comment A 6j multiplicity paradox
Downloaded :-) I hope I can find the hole in my logic now myself, but still would appreciate a direct answer, although I checked the "answered" button. (Note added in reading: Argl, how do associtativity matrices relate to 6j symbols? In any case, Ax|xxx is 6-dimensional so this should mean my case A is true. Shrug.)
Dec
2
accepted A 6j multiplicity paradox
Dec
1
asked A 6j multiplicity paradox
Dec
1
comment The resolution of which conjecture/problem would advance Mathematics the most?
What about specializing to applications? My life wouldn't change if the Riemann hypothesis is proven/disproven, and knowing P=/!=NP also not necessarily would have THAT impact with computers.
Oct
22
comment Classification properties of fusion rings
(contd) Assume you do their construction, but no crossings are allowed in the cubic graph. I think you still can get an invariant, with "Elliott" 6j symbols. If someone could tell me the smallest self-dual, no multiplicity fusion ring that is NOT ribbon, I could try my Clebsch-O-Matic on it and settle the matter. (A try with AA=1,AB=B,B*B=1+A+2B suggests you are right but don't know whether I programmed multiplicity correctly.)
Oct
22
comment Classification properties of fusion rings
@Turion: Thus "style" - I don't know enough on the field.
Oct
21
asked Classification properties of fusion rings
Oct
9
accepted No basis change in a fusion ring allowed?
Oct
8
asked No basis change in a fusion ring allowed?
Jul
14
revised Non-semisimple Lie algebra tensors
Reduced it to the relevant. May go into details with new question.
Jul
11
comment Non-semisimple Lie algebra tensors
Also: If you start with the tensor $C^i_{jk}$ and you can NOT invert $g_{lm}$ to get "the indices up", how do you arrive at $g^{no}$ at all? (I'm always working with matrix generators, thus my "complex conjugate transpose").
Jul
11
comment Non-semisimple Lie algebra tensors
I'm not at all familiar with Lie algebras, but obviously e.g. $C_{ijk}$ is identically zero for aff1 (because of dimension 2). Do you include this degenerate possibility in your statement? (Do such Lie algebras have a special name?)
Jul
10
revised Non-semisimple Lie algebra tensors
More definitions. Expanded.
Jul
9
asked Non-semisimple Lie algebra tensors
Jul
2
awarded  Inquisitive
Jul
2
awarded  Curious
Jun
7
comment “Multiplying” Clebsch-Gordan series
Yup, those. And after perusing his opus magnum for three years or so I understand it a bit :-) But we have digressed so much that we better take this issue to PM... (reddmannatchemiedotuni-hamburgdotde)
Jun
2
comment “Multiplying” Clebsch-Gordan series
You're right. Problem is I have no formal education in higher math and usually don't even know the correct terms. In any case, you can peek into "Birdtracks" by Cvitanovic (he's kind of a maverick too, but at least he knows the math :-) - on p. 232 of his "Group Theory" pdf I found the 8^2=1+9+27+27. The table header lists "Rep" so it's well possible that his vector spaces are built from several irreps.
May
30
comment “Multiplying” Clebsch-Gordan series
The span (?) of the vector space of $A\bigotimes{B}$ doesn't come out right otherwise! OK, you have then 8 irreps of (2,2,2)*(2,2,2) (I have to trust you on that) but still, it's vector space needs only four basis vectors to build the R matrix. (Is the span 8 nevertheless?) In all dimension formulas I know, the "clustered" irreps appear.