Professor Alexander Sobolev, PhD
Room 710
Tel:- 020-7679-2863
E-mail:- a.sobolev
ucl.ac.uk
Fax: 020-7383-5519
Research Interests
Spectral Theory, Differential Operators, Geometry of Numbers
Alex Sobolev's research area is spectral theory of partial differential operators. Current research is focused on proper ties of partial differential operators with periodic
coefficients. A fascinating feature of periodic operators is the
connection between their spectra and the properties of the underlying
periodicity lattice. This connection plays an important role in the proof
of the famous conjecture due to H.Bethe and A. Sommerfeld, which states that
the number of gaps in the spectrum is finite. Apart from analytic methods,
the rigorous mathematical proof of this fact involves methods from Number
Theory, and geometry of numbers.