Speaker:
Igor Krasovsky
Institution:
Imperial College, London
Time:
Thursday, April 6, 2017 - 2:00pm
Location:
RH 340P
Consider the almost Mathieu operator in the case of the critical coupling.
For rational frequencies p/q we obtain power-law bounds of the form 1/q^C
for the widths of the gaps close to the center of the spectrum. It follows that
these gaps remain open for the spectrum in the case of a certain class of Diophantine irrational frequencies.