Talk:Generalizations of Pauli matrices

Traceless ?

I suggest the following correction

[The generalized Gell-Mann matrices are Hermitian and traceless]

--->

[The generalized Gell-Mann matrices are Hermitian and (save $h 1 d$ ) traceless]

Duplicated section?

It looks to me like the section titled "A non-Hermitian generalization of Pauli matrices" describes exactly the same operators (or perhaps a transpose thereof) as the section titled "A unitary generalization of the Pauli matrices". Am I missing something here?

Dstahlke (talk) 14:19, 26 October 2012 (UTC)[reply]

Not much; the article is a disorganized mess. It should start by organizing the grading issues, the way they were laid out in the original reference, Patera, J.; Zassenhaus, H. (1988). "The Pauli matrices in n dimensions and finest gradings of simple Lie algebras of type An−1". Journal of Mathematical Physics. 29 (3): 665. Bibcode:1988JMP....29..665P. doi:10.1063/1.528006., which is oddly missing here. Sylvester did it all, of course, in the 1880s, but skipping the modern perspective and obscuring the facts you mention makes the article useless. I fear you must intervene. Cuzkatzimhut (talk) 15:08, 26 October 2012 (UTC)[reply]

Textbook language?

In this article one can read "Clearly the family specified by above consists of unitary matrices. To see that they indeed generalize the Pauli matrices, in some sense, we compute...". "Clearly"? (What about telling us ignorants why it is so clear?!) And who are the "we" that compute? --Episcophagus (talk) 00:56, 2 November 2012 (UTC)[reply]

I agree with your distaste of the false pedagogy of that section, and, as I argued above, it would improve the article by completely disappearing. I adduced the standard one-liner summary of it in the previous section. If you are familiar with unitarity, which i wikilinked, now, the unitarity of these sylvester matrices should be self-evident. "Clearly" might sound condescending, but it is a salutary signal that there is nothing deep involved: one simply writes its articulation on a line with an equal sign, and collapses the orthonormal vectors v that person uses. Now, why she/he switches notation for the roots of unity to ξ instead of the prior σ, and why he/she references that idiosyncratic obscure last reference, we might never know. It would be a kindness to the reader to have that section go.Cuzkatzimhut (talk) 14:56, 2 November 2012 (UTC)[reply]

Enquiring minds want to know...

So the shift operator lies at the core of the definition of a measure preserving dynamical system. See Bernoulli process for the simplest, most basic example. See also baker's map for a slightly more complicated version. it's already known that if one throws in a "clock matrix" into the works, at least for these two simple cases, that one gets the various period-doubling fractals. Its also known that the period doubling fractals describe the trajectory of one of the simplest possible quantum finite automata. It's also known that Vandermonde matrices describe iterated function sequences. This is all "common knowledge" in ergodic theory. What is not known, not clear, is how or if this has overlap onto Clifford algebras. That is, this article describes a generalization of the Pauli matrices, cooked up by Weyl. CXlearly the Pauli matrices are at the heart of Clifford algebras. From this article, we learn that Sylvester can use this to build a basis for gl(n,C). We learn that the n->infty limit is Poisson-something ... Poisson algebra? Poisson manifold? And we know that Poisson algebras are more-or-less the same thing as affine Lie algebras and quantum groups. So, now, lets connect the dots. If I take some rando measure-preserving dynamical system (lets pick some conservative system to make it easy), the time operator T for which I can interpret as a shift operator; what happens if I now throw in a clock operator, as defined in this article? Do I get some rando quantum group? How does that work out? Yes, I am aware that this comment really does not belong here. I'm not expecting an answer... 67.198.37.16 (talk) 23:52, 17 November 2020 (UTC)[reply]

This is not a forum. You may delete your rant unless it proposes concrete improvements. The "cooking up by Weyl" is egregiously false, given Sylvester's 19th century priorities. There are excellent yeomanly review articles covering several of your points, breezed over. The last reference links up to the Poisson Bracket algebra limit. Cuzkatzimhut (talk) 01:27, 18 November 2020 (UTC)[reply]

Mergeto Generalized Clifford algebra?

The wikilink Clock and shift matrices redirects to Generalized Clifford algebra which then proceeds to duplicate much of the bottom half of this article. Perhaps the bottom half of this article should be merged into Generalized Clifford algebra? I say this in part because the top half and the bottom half of this article seem to have little to do with one-another; its not clear what the unifying theme is supposed to be, other than they are both generalizations. Perhaps the top half is related to the bottom half by some similarity xform, but if so, this is not clear. 67.198.37.16 (talk) 01:31, 15 January 2024 (UTC)[reply]