This paper investigates observable signatures of hot spots orbiting Reissner-Nordström(RN)black holes and naked singularities.For an RN black hole,we find two discernible lensing image tracks in time integrated i...This paper investigates observable signatures of hot spots orbiting Reissner-Nordström(RN)black holes and naked singularities.For an RN black hole,we find two discernible lensing image tracks in time integrated images,capturing a complete orbit of hot spots and a image shadow within the critical curve where photons with a small impact parameter fall into the event horizon.Conversely,in RN singularities,additional image tracks can be found within the critical curve,originating from photons reflected by the infinitely high effective potential well.Moreover,we find incomplete and converging tracks from the time integrated images of hot spot orbiting RN singularities that have no photon sphere.The presence of these additional image tracks significantly influences temporal magnitudes at their local maxima,enabling us to differentiate between RN black holes and RN naked singularities.展开更多
In this study,we have investigated the mathematical components of the Dirac equation in curved spacetime and how they can be applied to the analysis of neutrino oscillations.More specifically,we have developed a metho...In this study,we have investigated the mathematical components of the Dirac equation in curved spacetime and how they can be applied to the analysis of neutrino oscillations.More specifically,we have developed a method for calculating the phase shift in flavor neutrino oscillations by utilizing a Taylor series expansion of the action that takes into account△m^(4) orders.In addition,we have used this method to assess how the phase difference in neutrino mass eigenstates changes according to the gravitational field described by the Johannsen spacetime.展开更多
基金Supported in part by the National Natural Science Foundation of China(12105191,11947225,11875196)。
文摘This paper investigates observable signatures of hot spots orbiting Reissner-Nordström(RN)black holes and naked singularities.For an RN black hole,we find two discernible lensing image tracks in time integrated images,capturing a complete orbit of hot spots and a image shadow within the critical curve where photons with a small impact parameter fall into the event horizon.Conversely,in RN singularities,additional image tracks can be found within the critical curve,originating from photons reflected by the infinitely high effective potential well.Moreover,we find incomplete and converging tracks from the time integrated images of hot spot orbiting RN singularities that have no photon sphere.The presence of these additional image tracks significantly influences temporal magnitudes at their local maxima,enabling us to differentiate between RN black holes and RN naked singularities.
基金Supported by the Grants F-FA-2021-510 from the Uzbekistan Ministry for Innovative Development。
文摘In this study,we have investigated the mathematical components of the Dirac equation in curved spacetime and how they can be applied to the analysis of neutrino oscillations.More specifically,we have developed a method for calculating the phase shift in flavor neutrino oscillations by utilizing a Taylor series expansion of the action that takes into account△m^(4) orders.In addition,we have used this method to assess how the phase difference in neutrino mass eigenstates changes according to the gravitational field described by the Johannsen spacetime.
