From mboxrd@z Thu Jan 1 00:00:00 1970 To: 9fans@cse.psu.edu From: "Douglas A. Gwyn" Message-ID: <3C57AF73.727F8CE9@null.net> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit References: <3C561EC9.88F86501@null.net>, <15446.32000.710318.879017@nanonic.hilbert.space> Subject: Re: [OT] Re: [9fans] Getting started in Plan9 - help Date: Wed, 30 Jan 2002 09:29:18 +0000 Topicbox-Message-UUID: 491b2ee0-eaca-11e9-9e20-41e7f4b1d025 paurea@gsyc.escet.urjc.es wrote: > I don't think so. [The "cross product"] is the dual of the > sesquilineal projection of the tensorial product. ... As usually defined the c.p. is supposed to result in the same type as its arguments, but e.g. the c.p. of two vectors is *not* a vector (it's a so-called pseudo- or axial vector, which can indeed be thought of as a *component* of the tensor product). So while it might be a "product" it is not as nice as the kinds of products that map from space x space into space. The "non-conservation of parity" work that was awarded a Nobel prize seems to actually have been confusion on this very score.