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direct sum of matrices

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Hello -

I am wondering if you would mind my adding a short exposition to you post concerning Sum and Direct Sum.

I have proved some fundamental results and would like to post them and get some input.

Patrick J. O'Hara

Dear Chi Woo:

Thank you so much. I am working on two(2) proofs related to linear operators and matrices that appear directly related to what your addition is stating.

The challenge will then be to articulate this connection.
It may be some time before I actually make the addition. If you like, I can notify you beforehand.


Wd like to introduce self as a non-academic mathematician

Q: I have a paper ready for publishing on arxiv.I would also like to publish it on in planetmath ( preferably only pdf).

a) How do I go about it? b)Is it ethically ok?


a. Click on "add to papers" on the menu bar on the left and
fill in the form that appears.

b. As far as PlanetMath is concerned, all that matters is that
it is legal to distribute your article online. Basically, if
you haven't signed a contract with a publisher (which usually
gives the publisher the copyright) and provide a rights statement
which gives permission to distribute your work electronically,
there should be no problem.


Yes if you are a registered participate and agree to the user terms that are part of the membership agreement. So you would need to register first.

Then, if it is an actual paper, there is a section "add to" on the side. Just click "Papers" and follow directions. The file upload is on the very bottom of the "add to papers" page.

If you have further questions, go to the "Forum" section under "Help using planetmath" and an Administrator can help you.

Best wishes.


What are the steps for registration pl? Tks,

I have not yet received guidance on

becoming a member pl.

If you are able to post messages in this forum, you are a member of PlanetMath.

If you want to contribute a paper or an exposition here, click on the appropriate links on the left pane and proceed. The same follows if you want to contribute a Encyclopedia entry, except in this case you'd need to know some LaTeX. There's another way to add entries: if you want to write something that is related to an existing entry, scroll to the bottom of that entry, and click add (or add example), and then proceed as usual.

Let us know if you have any other questions.

Thank you very much;I will try as directed.

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