The transverse-traceless gauge condition is an important concept in the theory of gravitational waves.It is well known that a vacuum is one of the key conditions to guarantee the existence of the transverse-traceless ...The transverse-traceless gauge condition is an important concept in the theory of gravitational waves.It is well known that a vacuum is one of the key conditions to guarantee the existence of the transverse-traceless gauge.Although it is thin,the interstellar medium is ubiquitous in the Universe.Therefore,it is important to understand the concept of gravitational waves when matter is presented.Bondi-Metzner-Sachs theory has solved the gauge problem related to gravitational waves.But it does not help with cases when the gravitational wave propagates in matter.This paper discusses possible extensions of the transverse-traceless gauge condition to Minkowski perturbation with matter presented.展开更多
We study the spontaneous decoherence of coupled harmonic oscillators confined in a ring container, where the nearest-neighbor harmonic potentials are taken into consideration. Without any external symmetry-breaking fi...We study the spontaneous decoherence of coupled harmonic oscillators confined in a ring container, where the nearest-neighbor harmonic potentials are taken into consideration. Without any external symmetry-breaking field or surrounding environment, the quantum superposition state prepared in the relative degrees of freedom gradually loses its quantum coherence spontaneously.This spontaneous decoherence is interpreted by the gauge couplings between the center-of-mass and the relative degrees of freedoms, which actually originate from the symmetries of the ring geometry and the corresponding nontrivial boundary conditions.In particular, such spontaneous decoherence does not occur at all at the thermodynamic limit because the nontrivial boundary conditions become the trivial Born-von Karman boundary conditions when the perimeter of the ring container tends to infinity.Our investigation shows that a thermal macroscopic object with certain symmetries has a chance for its quantum properties to degrade even without applying an external symmetry-breaking field or surrounding environment.展开更多
基金supported in part by the National Key Research and Development Program of China Grant No.2021YFC2203001in part by the NSFC(Grant Nos.11920101003,12021003 and 12005016)+1 种基金supported by‘the Fundamental Research Funds for the Central Universities’of Beijing Normal Universitysupported by the NSF of Hunan province(Grant No.2023JJ30179)。
文摘The transverse-traceless gauge condition is an important concept in the theory of gravitational waves.It is well known that a vacuum is one of the key conditions to guarantee the existence of the transverse-traceless gauge.Although it is thin,the interstellar medium is ubiquitous in the Universe.Therefore,it is important to understand the concept of gravitational waves when matter is presented.Bondi-Metzner-Sachs theory has solved the gauge problem related to gravitational waves.But it does not help with cases when the gravitational wave propagates in matter.This paper discusses possible extensions of the transverse-traceless gauge condition to Minkowski perturbation with matter presented.
基金supported by the National Natural Science Foundation of China(Grant Nos.11504241,and 11374032)the National Key Basic Research Program(Grant No.2014CB848700)Natural Science Foundation of Shenzhen University(Grants No.201551)
文摘We study the spontaneous decoherence of coupled harmonic oscillators confined in a ring container, where the nearest-neighbor harmonic potentials are taken into consideration. Without any external symmetry-breaking field or surrounding environment, the quantum superposition state prepared in the relative degrees of freedom gradually loses its quantum coherence spontaneously.This spontaneous decoherence is interpreted by the gauge couplings between the center-of-mass and the relative degrees of freedoms, which actually originate from the symmetries of the ring geometry and the corresponding nontrivial boundary conditions.In particular, such spontaneous decoherence does not occur at all at the thermodynamic limit because the nontrivial boundary conditions become the trivial Born-von Karman boundary conditions when the perimeter of the ring container tends to infinity.Our investigation shows that a thermal macroscopic object with certain symmetries has a chance for its quantum properties to degrade even without applying an external symmetry-breaking field or surrounding environment.
