4 papers
cond-mat.other2025
Why a Bose-Einstein condensate cannot exist in a system of interacting bosons at ultrahigh temperatures
Maksim D. Tomchenko
It is well known that a Bose-Einstein (BE) condensate of atoms exists in a system of interacting Bose atoms at , where is the BE condensation t…
cond-mat.quant-gas2025
Is a phonon excitation of a superfluid Bose gas a Goldstone boson?
Maksim Tomchenko
It is generally accepted that phonons in a superfluid Bose gas are Goldstone bosons. This is justified by spontaneous symmetry breaking (SSB), which is usually defined as follows:…
cond-mat.quant-gas2023
Nonuniform Bose-Einstein condensate. II. Doubly coherent states
Maksim Tomchenko
We find stationary excited states of a one-dimensional system of spinless point bosons with repulsive interaction and zero boundary conditions by numerically solving the time-i…
cond-mat.quant-gas2023
Nonuniform Bose-Einstein condensate. I. An improvement of the Gross-Pitaevskii method
Maksim Tomchenko
A nonuniform condensate is usually described by the Gross-Pitaevskii (GP) equation, which is derived with the help of the c-number ansatz .…