Topological defect formation in rotating binary dipolar Bose–Einstein condensate

2016 ◽  
Vol 375 ◽  
pp. 368-377 ◽  
Author(s):  
Xiao-Fei Zhang ◽  
Wei Han ◽  
Hai-Feng Jiang ◽  
Wu-Ming Liu ◽  
Hiroki Saito ◽  
...  
2016 ◽  
pp. 126-131
Author(s):  
Peter Pikhitsa ◽  
Peter Pikhitsa

A Bose-Einstein condensate of bosons with repulsion, described by the Gross-Pitaevskii equation and restricted by an impenetrable “hard wall” (either rigid or flexible) which is intended to suppress the “snake instability” inherent for dark solitons, is considered. The Bogoliubov-de Gennes equations to find the spectra of gapless Bogoliubov excitations localized near the “domain wall” and therefore split from the bulk excitation spectrum of the Bose-Einstein condensate are solved. The “domain wall” may model either the surface of liquid helium or of a strongly trapped Bose-Einstein condensate. The dispersion relations for the surface excitations are found for all wavenumbers along the surface up to the ”free-particle” behavior , the latter was shown to be bound to the “hard wall” with some “universal” energy .


2021 ◽  
Vol 81 (10) ◽  
Author(s):  
Jorge Alfaro ◽  
Robinson Mancilla

AbstractIn this work, we present the thermodynamic study of a model that considers the black hole as a condensate of gravitons. In this model, the spacetime is not asymptotically flat because of a topological defect that introduces an angle deficit in the spacetime like in Global Monopole solutions. We have obtained a correction to the Hawking temperature plus a negative pressure associated with the black hole of mass M. In this way, the graviton condensate, which is assumed to be at the critical point defined by the condition $$\mu _{ch}=0,$$ μ ch = 0 , has well-defined thermodynamic quantities P, V, $$T_{h}$$ T h , S, and U as any other Bose–Einstein condensate (BEC). In addition, we present a formal equivalence between the Letelier spacetime and the line element that describes the graviton condensate. We also discuss the Kiselev black hole, which can parametrize the most well-known spherically symmetric black holes. Finally, we present a new metric, which we will call the BEC–Kiselev solution, that allows us to extend the graviton condensate to the case of solutions with different matter contents.


2021 ◽  
Vol 126 (3) ◽  
Author(s):  
T. Dieterle ◽  
M. Berngruber ◽  
C. Hölzl ◽  
R. Löw ◽  
K. Jachymski ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document