Added the definitions of type I, type II_1, type II_∞, type III_0, type III_1, and type III_λ factors.

]]>I guess something like this is where the terminology comes from. The answer is probably in

- John von Neumann,
*On rings of operators, reduction theory*, Annals of Mathematics Second Series, Vol. 50, No. 2 (1949) (jstor)

Urs, 3

factor in a product;

von Neumann algebra factor

To some extent, the second is a special case of the first, when one writes an operator algebra by direct integrals, am I right ?

]]>added a pointer at *von Neumann algebra factor* to the recent

- Vaughan Jones, Scott Morrison, Noah Snyder, The classification of subfactors of index at most 5 (arXiv:1304.6141)

With a little luck somebody will feel insoired to add a bit of content to that entry (or better yet, creae a dedicated one on subfactors)…

]]>I created factor

]]>I think it will be difficult to *find* this entry. I mean if I want an entry about factors I will hardly type specific phrase *von Neumann algebra factor*. On the other hand having factor means having many meanings of the word. Should we have a disambiguation page for factor or what ?

stub for von Neumann algebra factor

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