nomadreid
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- (finite vector spaces) 3 notations: (a) physicists and others: (u,v)=v*u linear in v. (b) some mathematicians:(u,v)=u*v linear in u. (c) bra-ket: <v|u>= (u,v) from (a), so v*u, but linear in u. Seems to contradict.
First, I need to check that I have the 3 notations correct for an inner product in finite vector spaces over a complex field; v* means: given the isomorphism V to V* then:
(a) physicists and others: (u,v)=v*u ; linear in the second argument
(b) some mathematicians: (u,v)=u*v; linear in the first argument.
(c) bra-ket: <v|u>= (u,v) from (a), so v*u . <v|u> is linear in the second argument.
If these are correct, then it would seem that <v|u> being linear in the second argument (u) would imply that it would be linear in the first argument (u) for the physicist's version (a), reducing it to (b). But that is wrong. What is my confusion?
Edit: according to
https://en.wikipedia.org/wiki/Riesz...cs_notations_and_definitions_of_inner_product
my (a) does not exist. I cannot give a source for (a), as I saw this and noted it down some time ago without noting the sources. Is the solution therefore that <v|u>= (u,v) from (b)? That is, that they are both u*v ?
(Thanks for the patience with elementary questions like this one.)
(a) physicists and others: (u,v)=v*u ; linear in the second argument
(b) some mathematicians: (u,v)=u*v; linear in the first argument.
(c) bra-ket: <v|u>= (u,v) from (a), so v*u . <v|u> is linear in the second argument.
If these are correct, then it would seem that <v|u> being linear in the second argument (u) would imply that it would be linear in the first argument (u) for the physicist's version (a), reducing it to (b). But that is wrong. What is my confusion?
Edit: according to
https://en.wikipedia.org/wiki/Riesz...cs_notations_and_definitions_of_inner_product
my (a) does not exist. I cannot give a source for (a), as I saw this and noted it down some time ago without noting the sources. Is the solution therefore that <v|u>= (u,v) from (b)? That is, that they are both u*v ?
(Thanks for the patience with elementary questions like this one.)
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