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Spectral perturbation theory of discrete spectra in presence of continuous spectrum

This is a 2 part question: 1). I am looking for a (hopefully accessible to beginning grad student who knows matrix perturbation theory) reference for doing concrete calculations of perturbed discrete ...
Piyush Grover's user avatar
4 votes
1 answer
155 views

Resource on spectral theory for differential operators with symmetry groups

In Methods of Mathematical Physics IV by Reed and Simon, the authors cover Floquet theory in detail in Section XIII.16. On page 280, they note that "A part of the analysis of [the periodic ...
Yonah Borns-Weil's user avatar
2 votes
0 answers
145 views

Are Weyl sequences polynomially bounded?

Look at the Hilbert space $l^2( \mathbb{Z}) $ and let $A$ be a translation invariant band operator. I.e. if $\{ e_n \}_{n \in \mathbb Z} $ is the standard basis for $l^2( \mathbb{Z}) $ then it holds ...
Frederik Ravn Klausen's user avatar
4 votes
0 answers
134 views

What is known about the density of states for the Anderson Model?

The Anderson Model is given by the random Hamiltonian (as an operator on $l^2(\mathbb{Z}^d)$) $$ H_\omega = - \triangle + V(\omega) $$ where $V(\omega) \mid x \rangle = \omega(x) \mid x \rangle$ ...
Frederik Ravn Klausen's user avatar
1 vote
0 answers
128 views

Angular excitations and Schrodinger operators with radial potential in N-dimensions

Can someone please explain the following in mathematical language? "First of all, angular excitations only push the energy up, never down, so it is enough to analyze spherically symmetric s-waves....
user2002's user avatar
  • 141
6 votes
3 answers
2k views

Some explanation about Dynin's formalism

I have seen this claim on the Wikipedia page for the Yang-Mills Millenium problem by Alexander Dynin. He is a mathematician working at the Department of Mathematics of Ohio State University and so, I ...
Jon's user avatar
  • 1,687
6 votes
0 answers
200 views

Spectral theory for Dirac Laplacian on a funnel

I would like to study the spectral theory of the Dirac Laplacian on a non-compact quotient of the hyperbolic plane by a discrete group (I am particularly interested in the simple case where the ...
harlekin's user avatar
  • 313