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Mathematicians prove Pólya's conjecture for the eigenvalues of a disk

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Re: Mathematicians prove Pólya's conjecture for the eigenvalues of a disk

#6
post #3

Mathematicians prove that you can deduce the shape of disk based on the frequencies it produces when you hit it with a stick.

[flagged]

I’m sorry. As a machine model, I cannot condone acts of violence against disks. Have you tried discussing your differences between you, perhaps with the assistance of some professional mediator?

Re: Mathematicians prove Pólya's conjecture for the eigenvalues of a disk

#9
The title words remind of an unrelated fact, Gershgorin Disks:

  The eigenvalues of any N x N matrix, A, 
  are contained in the union of N discs in the complex plane. 
  The center of the i_th disc is the i_th diagonal element of A. 
  The radius of the i_th disc is the absolute values 
  of the off-diagonal elements in the i_th row. 
https://blogs.sas.com/content/iml/2019/05/22/gershgorin-disc...

It's rather remarkable, unexpected, and perhaps shocking, when you first hear it. There does not seem to be enough information to make it true. But it is.

I used it in a real project to cancel noise.

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