Constraint on M to keep M^T * A * M positive semidefinite?

perplexabot
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Hey all! Let me get right to it!
It is given that $$A \succeq 0$$
I need the following to hold for M: $$M^TAM\succeq 0$$

What are the constraints or conditions on M for M^TAM\succeq 0 to hold?

Anything would help at this point... I am open to discussion.

Note: It may be worth mentioning that A is a given matrix where as M is variable.

Thank you for reading : )
 
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It is always true. For any ##M##.
 
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micromass said:
It is always true. For any ##M##.
Interesting, I think I see why that is. xM^TAMx \succeq 0 => y^TAy \succeq 0

Thanks for the quick answer. I may have a follow up question later :P
 

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