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Jan 16, 2018 at 4:57 comment added fereidoun I am so sorry about that. you are right, but as your first comment, to prove Morita equivalence of two Banach algebras, we must first prove that they are self-induced, so I guessed that the above identification must first be prove. Anyway, thank you so much for your remarks.
Jan 15, 2018 at 17:57 history rollback Yemon Choi
Rollback to Revision 4
Jan 15, 2018 at 17:57 comment added Yemon Choi You have now changed the question completely, this is not fair on the previous commenters. Please ask your new question as a separate question. I am reverting this to the original version, since your original question about Morita equivalence does not seem to be directly related to your second question about being self-induced
Jan 15, 2018 at 12:48 review Reopen votes
Jan 15, 2018 at 17:59
Jan 15, 2018 at 12:28 history edited fereidoun CC BY-SA 3.0
added 558 characters in body; edited title
Jan 15, 2018 at 9:22 history closed abx
Jeremy Rickard
Michael Albanese
David Handelman
coudy
Needs details or clarity
Jan 14, 2018 at 21:37 comment added Yemon Choi @fereidoun also, please explain to us what you meant when you said "Morita equivalence", because it was not clear from the formulation of your question where you had seen this definition and what you think it means
Jan 14, 2018 at 21:36 comment added Yemon Choi @fereidoun, please edit your question so that it contains the correct definition. Incidentally "$\ell_1$-Munn Banach space" is bad terminology in my view, and I wish people would not use it.
Jan 14, 2018 at 10:36 comment added fereidoun Let A be a unital Banach algebra, and $I$ be an arbitrary index set, and let $M_ I (A)$ be the vector space of all $I × I$-matrices $A=(A_i j)$ over $A$ such that $\norm A =\Sigma_i,j\in I \norm A_i j $. Then, it is easy to check that $M_I (A)$ with scaler multiplication, matrix addition, and the above norm is a Banach space. This Banach space is called $\ell_1-Munn$ Banach space over A. If $M_I (A)$ is a Banach algebra, by product as above ($P$ be the $I*I$ matrix with $a_i j=0$ and $a_i i=1_A$), then $M_I (A)$ is called the $\ell_1-Munn$ Banach algebra over $A$ with index set I.
Jan 13, 2018 at 18:40 review Close votes
Jan 15, 2018 at 9:22
Jan 13, 2018 at 18:35 comment added Yemon Choi @Mare I think it is up to the OP to clarify what he means, since the question seems currently ill-posed
Jan 13, 2018 at 17:31 comment added Benjamin Steinberg If P is invertible then your Munn algebra is isomorphic to a usual matrix algebras on I.
Jan 13, 2018 at 17:15 history edited YCor
edited tags
Jan 13, 2018 at 14:28 comment added Mare I did not know about other notions of Morita equivalence or the definition of the multiplication when I answered. So if necessary I will delete my answer in case it was off topic.
Jan 13, 2018 at 14:24 comment added Yemon Choi As @QiaochuYuan has pointed out, in order for $aPb$ to be well-defined, you must specify some extra conditions on $M_I(A)$, such as convergence with respect to some norm. I have downvoted the question until this is clarified.
Jan 13, 2018 at 14:23 history edited Yemon Choi
added the BA tag since I expect the OP is thinking about a BA notion of Morita equivalence
Jan 13, 2018 at 14:22 comment added Yemon Choi If you are thinking of what some people like to call Munn algebras, which in turn are motivated by convolution algebras of Rees semigroups, then there was some discussion in a paper of Gourdeau, Gronbaek and White, Studia Mathematica, published between 2005 to 2010 I think?
Jan 13, 2018 at 14:20 comment added Yemon Choi It is not entirely clear, in the world of Banach algebras, what the "correct" notion of Morita equivalence should be. One possibility was investigated by Niels Gronbaek in a paper in the 1990s in JPAA (I don't have the details to hand right now)
S Jan 13, 2018 at 13:49 history suggested fereidoun CC BY-SA 3.0
the product of $M_I(A)$
Jan 13, 2018 at 13:12 review Suggested edits
S Jan 13, 2018 at 13:49
Jan 13, 2018 at 11:47 comment added Qiaochu Yuan How is $M_I(A)$ a Banach algebra if $I$ is infinite? How do you define multiplication?
Jan 13, 2018 at 9:51 answer added Mare timeline score: 7
Jan 13, 2018 at 9:41 review First posts
Jan 13, 2018 at 9:49
Jan 13, 2018 at 9:41 history asked fereidoun CC BY-SA 3.0