A general-relativistic model is formulated for hypothetical ultra-compact astrophysical objects composed of fluid infused with charges carrying a generalized massless Maxwell-Proca field. The chosen interior metric ha...A general-relativistic model is formulated for hypothetical ultra-compact astrophysical objects composed of fluid infused with charges carrying a generalized massless Maxwell-Proca field. The chosen interior metric has the algebraic property that;the fluid consequently possesses a negative pressure which halts gravitational collapse and establishes hydrostatic equilibrium. For an object containing a global distribution of non-interacting Maxwell-Proca charges, it is shown that physical considerations define the relationship between the charge density and the metric function uniquely, corroborating an earlier finding (for an electrostatic distribution of charge) that the interior field must increase with radial distance and the exterior field necessarily follows an inverse-square law. For the case of a charged fluid envelope surrounding a core of uncharged fluid, numerous solutions are possible. Assuming the interior field to vary as rn and requiring its strength to increase with radial distance while the charge density decreases, the range of values for n is found to be 0 n ≤ 1 (where n is not necessarily an integer) with n = 1 denoting the special case of a continuous distribution of charge. For both continuous and stratified charge distributions, the exterior field is found to decrease as 1/r2?regardless of the interior field’s dependence on r.展开更多
Based on the physical metric proposed by the author, temperature distribution for compact objects, neutron stars and black holes, has been explained. Outside the extended horizon, the temperature is positive and appro...Based on the physical metric proposed by the author, temperature distribution for compact objects, neutron stars and black holes, has been explained. Outside the extended horizon, the temperature is positive and approaches infinity at the extended horizon boundary. Inside the extended horizon, the temperature is negative which implies higher temperature than outside the horizon. This outcome is the result of the repulsive nature of gravity inside the extended horizon in the author’s physical metric. Overall, the physical metric explains temperature structure of compact objects more completely than the Schwarzschild metric, and is supported by the emerging evidence of X-ray data collected from neutron stars and black holes (AGN).展开更多
An asymptotic method has been developed for investigation of kinetics of formation of compact objects with strong internal bonds. The method is based on the uncertainty relation for a coordinate and a momentum in spac...An asymptotic method has been developed for investigation of kinetics of formation of compact objects with strong internal bonds. The method is based on the uncertainty relation for a coordinate and a momentum in space of sizes of objects (clusters) with strongly pronounced collective quantum properties resulted from exchange interactions of various physical nature determined by spatial scales of the processes under consideration. The proposed phenomenological approach has been developed by analogy with the all-known ideas about coherent states of quantum mechanical oscillator systems for which a product of coordinate and momentum uncertainties (dispersions) accepts the value, which is minimally possible within uncertainty relations. With such an approach the leading processes are oscillations of components that make up objects, mainly: collective nucleon oscillations in a nucleus and phonon excitations in a mesostructure crystal lattice. This allows us to consider formation and growth of subatomic and mesoscopic objects in the context of a single formalism. The proposed models adequately describe characteristics of formation processes of nuclear matter clusters as well as mesoscopic crystals having covalent and quasi-covalent bonds between atoms.展开更多
We have performed Monte Carlo simulations of the rotation of single stars and companions of compact objects(The compact objects are white dwarfs(WDs) and neutron stars(NSs)) in close binaries.We present a comparison b...We have performed Monte Carlo simulations of the rotation of single stars and companions of compact objects(The compact objects are white dwarfs(WDs) and neutron stars(NSs)) in close binaries.We present a comparison between the rotation of companions of compact objects and that of single stars.We find that the rotation of the companions of compact objects is on average faster than that of the single stars.According to the distribution of the orbital period and the rotation angular velocity,we find that the rotation of the companions of compact objects is mostly accelerated by stable mass transfer.Tidal forces of the compact object can also affect the rotation of companion.展开更多
We present results of MERLIN observations of five compact radio sources at 1.6 GHz, part of a large survey to identify compact symmetric objects (CSOs). We give for the first time MERLIN maps of two sources, 1604+315 ...We present results of MERLIN observations of five compact radio sources at 1.6 GHz, part of a large survey to identify compact symmetric objects (CSOs). We give for the first time MERLIN maps of two sources, 1604+315 and 1751+278. The five observed sources show very compact, unresolved point-like structure, which may imply that they are good CSO candidates.展开更多
This paper presents the Pareto solutions in continuous multi-objective mathematical programming. We discuss the role of some assumptions on the objective functions and feasible domain, the relationship between them, a...This paper presents the Pareto solutions in continuous multi-objective mathematical programming. We discuss the role of some assumptions on the objective functions and feasible domain, the relationship between them, and compactness, contractibility and fixed point properties of the Pareto sets. The authors have tried to remove the concavity assumptions on the objective functions which are usually used in multi-objective maximization problems. The results are based on constructing a retraction from the feasible domain onto the Pareto-optimal set.展开更多
The problem of dynamic relocation and phase-out of combined manufacturingplant and warehousing facilities in the supply chain are concerned. A multiple time/multipleobjective model is proposed to maximize total profit...The problem of dynamic relocation and phase-out of combined manufacturingplant and warehousing facilities in the supply chain are concerned. A multiple time/multipleobjective model is proposed to maximize total profit during the time horizon, minimize total accesstime from the plant/warehouse facilities to its suppliers and customers and maximize aggregatedlocal incentives during the time horizon. The relocation problem keeps the feature of NP-hard andwith the traditional method the optimal result cannot be got easily. So a compact genetic algorithm(CGA) is introduced to solve the problem. In order to accelerate the convergence speed of the CGA,the least square approach is introduced and a fast compact genetic algorithm (fCGA) is proposed.Finally, simulation results with the fCGA are compared with the CGA and classical integerprogramming (IP). The results show that the fCGA proposed is of high efficiency for Paretooptimality problem.展开更多
The discovery of gravitational waves resulting from the merger of two massive black holes (GW150914) has revolutionized our view of merging compact binaries. Recently, the Swope Supernova Survey of the optical counter...The discovery of gravitational waves resulting from the merger of two massive black holes (GW150914) has revolutionized our view of merging compact binaries. Recently, the Swope Supernova Survey of the optical counterpart of a gravitational wave event in the NGC 4993 galaxy, GW170817, emanating from the merger of two neutron stars, has triggered a lot of research work. Emphasis has been on comparing the existing theoretical models with the observational data, allowing for the prospect of an even more stringent test of general relativity. The afterglow of this event was observed in a wide range of wavelengths extending from radio waves to gamma rays. In this work, we first explore the evolutionary pathways of compact binary systems following the in-spiral, merger, and ring down sequence. We then proceed to discuss the processes leading to the production of gravitational waves and electromagnetic emission resulting from the merger of compact objects, particularly neutron star binaries and neutron star-black hole systems. We construct a basic inventory of the energy released during the merger of compact binaries in all bands of the electromagnetic spectrum with emphasis on gamma-ray burst emission. The constraints on certain wavelength emissions, such as gamma-ray bursts, are discussed in terms of orbital dynamical instabilities, energy transfer processes, and possible jet orientations with respect to the observer. Finally, we explore the futuristic perspective of the impact of gravitational waves detection on our understanding of the working of the universe.展开更多
Approximate all-terrain spacetimes for astrophysical applications are presented. The metrics possess five relativistic multipole moments, namely, mass, rotation, mass quadrupole, charge,and magnetic dipole moment. All...Approximate all-terrain spacetimes for astrophysical applications are presented. The metrics possess five relativistic multipole moments, namely, mass, rotation, mass quadrupole, charge,and magnetic dipole moment. All these spacetimes approximately satisfy the Einstein-Maxwell field equations. The first metric is generated using the Hoenselaers-Perjés method from given relativistic multipoles. The second metric is a perturbation of the Kerr-Newman metric, which makes it a relevant approximation for astrophysical calculations. The last metric is an extension of the Hartle-Thorne metric that is important for obtaining internal models of compact objects perturbatively. The electromagnetic field is calculated using Cartan forms for locally non-rotating observers. These spacetimes are relevant for inferring properties of compact objects from astrophysical observations. Furthermore, the numerical implementations of these metrics are straightforward, making them versatile for simulating potential astrophysical applications.展开更多
In 2013, World-Universe Model (WUM) made one of the most important predictions: “Macroobjects of the World have cores made up of the discussed DM (Dark Matter) particles. Other particles, including DM and baryonic ma...In 2013, World-Universe Model (WUM) made one of the most important predictions: “Macroobjects of the World have cores made up of the discussed DM (Dark Matter) particles. Other particles, including DM and baryonic matter, form shells surrounding the cores” [1]. Prof. R. Genzel and A. Ghez confirmed this prediction: “The Discovery of a Supermassive Compact Object at the Centre of Our Galaxy” (Nobel Prize in Physics 2020). On May 12, 2022, astronomers, using the Event Horizon Telescope, released the first image of the accretion disk around the Sagittarius A* (Sgr A*) produced using a worldwide network of radio observatories made in April 2017. These observations were obtained by a global array of millimeter wavelength telescopes and analyzed by an international research team that now numbers over 300 people, which claimed that Sgr A* is a Supermassive Black Hole (SBH). In the present paper, we analyze these results in frames of WUM. Based on the totality of all accumulated experimental results for the Center of the Milky Way Galaxy we conclude that Sgr A* is the DM Core of our Galaxy.展开更多
文摘A general-relativistic model is formulated for hypothetical ultra-compact astrophysical objects composed of fluid infused with charges carrying a generalized massless Maxwell-Proca field. The chosen interior metric has the algebraic property that;the fluid consequently possesses a negative pressure which halts gravitational collapse and establishes hydrostatic equilibrium. For an object containing a global distribution of non-interacting Maxwell-Proca charges, it is shown that physical considerations define the relationship between the charge density and the metric function uniquely, corroborating an earlier finding (for an electrostatic distribution of charge) that the interior field must increase with radial distance and the exterior field necessarily follows an inverse-square law. For the case of a charged fluid envelope surrounding a core of uncharged fluid, numerous solutions are possible. Assuming the interior field to vary as rn and requiring its strength to increase with radial distance while the charge density decreases, the range of values for n is found to be 0 n ≤ 1 (where n is not necessarily an integer) with n = 1 denoting the special case of a continuous distribution of charge. For both continuous and stratified charge distributions, the exterior field is found to decrease as 1/r2?regardless of the interior field’s dependence on r.
文摘Based on the physical metric proposed by the author, temperature distribution for compact objects, neutron stars and black holes, has been explained. Outside the extended horizon, the temperature is positive and approaches infinity at the extended horizon boundary. Inside the extended horizon, the temperature is negative which implies higher temperature than outside the horizon. This outcome is the result of the repulsive nature of gravity inside the extended horizon in the author’s physical metric. Overall, the physical metric explains temperature structure of compact objects more completely than the Schwarzschild metric, and is supported by the emerging evidence of X-ray data collected from neutron stars and black holes (AGN).
文摘An asymptotic method has been developed for investigation of kinetics of formation of compact objects with strong internal bonds. The method is based on the uncertainty relation for a coordinate and a momentum in space of sizes of objects (clusters) with strongly pronounced collective quantum properties resulted from exchange interactions of various physical nature determined by spatial scales of the processes under consideration. The proposed phenomenological approach has been developed by analogy with the all-known ideas about coherent states of quantum mechanical oscillator systems for which a product of coordinate and momentum uncertainties (dispersions) accepts the value, which is minimally possible within uncertainty relations. With such an approach the leading processes are oscillations of components that make up objects, mainly: collective nucleon oscillations in a nucleus and phonon excitations in a mesostructure crystal lattice. This allows us to consider formation and growth of subatomic and mesoscopic objects in the context of a single formalism. The proposed models adequately describe characteristics of formation processes of nuclear matter clusters as well as mesoscopic crystals having covalent and quasi-covalent bonds between atoms.
基金supported by the National Natural Science Foundation of China (Grant No. 11163005)the Natural Science Foundation of Xinjiang(Grant No. 2009211B01)the Foundation of Huoyingdong (Grant No.121107)
文摘We have performed Monte Carlo simulations of the rotation of single stars and companions of compact objects(The compact objects are white dwarfs(WDs) and neutron stars(NSs)) in close binaries.We present a comparison between the rotation of companions of compact objects and that of single stars.We find that the rotation of the companions of compact objects is on average faster than that of the single stars.According to the distribution of the orbital period and the rotation angular velocity,we find that the rotation of the companions of compact objects is mostly accelerated by stable mass transfer.Tidal forces of the compact object can also affect the rotation of companion.
文摘We present results of MERLIN observations of five compact radio sources at 1.6 GHz, part of a large survey to identify compact symmetric objects (CSOs). We give for the first time MERLIN maps of two sources, 1604+315 and 1751+278. The five observed sources show very compact, unresolved point-like structure, which may imply that they are good CSO candidates.
文摘This paper presents the Pareto solutions in continuous multi-objective mathematical programming. We discuss the role of some assumptions on the objective functions and feasible domain, the relationship between them, and compactness, contractibility and fixed point properties of the Pareto sets. The authors have tried to remove the concavity assumptions on the objective functions which are usually used in multi-objective maximization problems. The results are based on constructing a retraction from the feasible domain onto the Pareto-optimal set.
基金This project is supported by National Natural Science Foundation of China (No.59889505, 70071017).
文摘The problem of dynamic relocation and phase-out of combined manufacturingplant and warehousing facilities in the supply chain are concerned. A multiple time/multipleobjective model is proposed to maximize total profit during the time horizon, minimize total accesstime from the plant/warehouse facilities to its suppliers and customers and maximize aggregatedlocal incentives during the time horizon. The relocation problem keeps the feature of NP-hard andwith the traditional method the optimal result cannot be got easily. So a compact genetic algorithm(CGA) is introduced to solve the problem. In order to accelerate the convergence speed of the CGA,the least square approach is introduced and a fast compact genetic algorithm (fCGA) is proposed.Finally, simulation results with the fCGA are compared with the CGA and classical integerprogramming (IP). The results show that the fCGA proposed is of high efficiency for Paretooptimality problem.
文摘The discovery of gravitational waves resulting from the merger of two massive black holes (GW150914) has revolutionized our view of merging compact binaries. Recently, the Swope Supernova Survey of the optical counterpart of a gravitational wave event in the NGC 4993 galaxy, GW170817, emanating from the merger of two neutron stars, has triggered a lot of research work. Emphasis has been on comparing the existing theoretical models with the observational data, allowing for the prospect of an even more stringent test of general relativity. The afterglow of this event was observed in a wide range of wavelengths extending from radio waves to gamma rays. In this work, we first explore the evolutionary pathways of compact binary systems following the in-spiral, merger, and ring down sequence. We then proceed to discuss the processes leading to the production of gravitational waves and electromagnetic emission resulting from the merger of compact objects, particularly neutron star binaries and neutron star-black hole systems. We construct a basic inventory of the energy released during the merger of compact binaries in all bands of the electromagnetic spectrum with emphasis on gamma-ray burst emission. The constraints on certain wavelength emissions, such as gamma-ray bursts, are discussed in terms of orbital dynamical instabilities, energy transfer processes, and possible jet orientations with respect to the observer. Finally, we explore the futuristic perspective of the impact of gravitational waves detection on our understanding of the working of the universe.
文摘Approximate all-terrain spacetimes for astrophysical applications are presented. The metrics possess five relativistic multipole moments, namely, mass, rotation, mass quadrupole, charge,and magnetic dipole moment. All these spacetimes approximately satisfy the Einstein-Maxwell field equations. The first metric is generated using the Hoenselaers-Perjés method from given relativistic multipoles. The second metric is a perturbation of the Kerr-Newman metric, which makes it a relevant approximation for astrophysical calculations. The last metric is an extension of the Hartle-Thorne metric that is important for obtaining internal models of compact objects perturbatively. The electromagnetic field is calculated using Cartan forms for locally non-rotating observers. These spacetimes are relevant for inferring properties of compact objects from astrophysical observations. Furthermore, the numerical implementations of these metrics are straightforward, making them versatile for simulating potential astrophysical applications.
文摘In 2013, World-Universe Model (WUM) made one of the most important predictions: “Macroobjects of the World have cores made up of the discussed DM (Dark Matter) particles. Other particles, including DM and baryonic matter, form shells surrounding the cores” [1]. Prof. R. Genzel and A. Ghez confirmed this prediction: “The Discovery of a Supermassive Compact Object at the Centre of Our Galaxy” (Nobel Prize in Physics 2020). On May 12, 2022, astronomers, using the Event Horizon Telescope, released the first image of the accretion disk around the Sagittarius A* (Sgr A*) produced using a worldwide network of radio observatories made in April 2017. These observations were obtained by a global array of millimeter wavelength telescopes and analyzed by an international research team that now numbers over 300 people, which claimed that Sgr A* is a Supermassive Black Hole (SBH). In the present paper, we analyze these results in frames of WUM. Based on the totality of all accumulated experimental results for the Center of the Milky Way Galaxy we conclude that Sgr A* is the DM Core of our Galaxy.
