Seminar “Theory of Condensed Matter”

Date and Time: Tuesday, 28 December 2021, at 4:00 PM

Venue: Blokhintsev lecture hall, Bogoliubov Laboratory of Theoretical Physics, online seminar on Zoom

Link to join the seminar via Zoom

Semianr topic: “Tan′s adiabatic sweep theorem in arbitrary dimension from the variational theorem for the scattering length”

Speaker: Alexander Cherny

Abstract:

It is shown that variation of the one-particle dispersion in a universal many-body system of arbitrary dimension enables us to obtain Tan’s adiabatic sweep theorem and its generalization. The derivation is based on the Hellmann-Feynman theorem and the variational theorem for the scattering length, suggested in our previous paper. The scheme is physically transparent and based on simple quantum mechanics. As an example, the universal effects in the system of spinless bosons are considered. In particular, the pair distribution function is calculated at short distances by means of the variation of the potential. The results can easily be generalized to the two-component fermions with interactions between opposite spins.