Some aspects of atom-field interactions in curved spacetime are reviewed.Of great interest are quantum radiative and entanglement processes arising out of Rindler and black hole spacetimes,which involve the role of Ha...Some aspects of atom-field interactions in curved spacetime are reviewed.Of great interest are quantum radiative and entanglement processes arising out of Rindler and black hole spacetimes,which involve the role of Hawking-Unruh and dynamical Casimir effects.Most of the discussion surrounds the radiative part of interactions.For this,we specifically reassess the conventional understandings of atomic radiative transitions and energy level shifts in curved spacetime.We also briefly outline the status quo of entanglement dynamics study in curved spacetime,and highlight literature related to some novel insights,like entanglement harvesting.On one hand,the study of the role played by spacetime curvature in quantum radiative and informational phenomena has implications for fundamental physics,notably the gravity-quantum interface.In particular,one examines the viability of the Equivalence Principle,which is at the heart of Einstein’s general theory of relativity.On the other hand,it can be instructive for manipulating quantum information and light propagation in arbitrary geometries.Some issues related to nonthermal effects of acceleration are also discussed.展开更多
Overcoming the diffraction limit is crucial for obtaining high-resolution images and observing fine microstructures.With this conventional difficulty still puzzling us and the prosperous development of wave dynamics o...Overcoming the diffraction limit is crucial for obtaining high-resolution images and observing fine microstructures.With this conventional difficulty still puzzling us and the prosperous development of wave dynamics of light interacting with gravitational fields in recent years,how spatial curvature affects the diffraction limit is an attractive and important question.Here we investigate the issue of the diffraction limit and optical resolution on two-dimensional curved space—surfaces of revolution(SORs)with constant or variable spatial curvature.We show that the diffraction limit decreases and the resolution is improved on SORs with positive Gaussian curvature,opening a new avenue to super-resolution.The diffraction limit is also influenced by the propagation direction,as well as the propagation distance in curved space with variable spatial curvature.These results provide a possible method to control the optical resolution in curved space or equivalent waveguides with varying refractive index distribution and may allow one to detect the presence of the nonuniform strong gravitational effect by probing locally the optical resolution.展开更多
Inbreeding depression(ID)refers to the undesirable effects of inbreeding(mating of relatives)on fitness-associated phenotypes(Charlesworth and Willis,2009).ID on production,reproduction,and health traits is relevant t...Inbreeding depression(ID)refers to the undesirable effects of inbreeding(mating of relatives)on fitness-associated phenotypes(Charlesworth and Willis,2009).ID on production,reproduction,and health traits is relevant to industrial profitability,making it important in animal management.Runs of homozygosity(ROH)is a good measure of inbreeding and autozygosity(the inheritance of two copies of an ancestral allele)(Alkuraya,2013).展开更多
As an analog model of general relativity,optics on some two-dimensional(2 D)curved surfaces has received increasing attention in the past decade.Here,in light of the Huygens-Fresnel principle,we propose a theoretical ...As an analog model of general relativity,optics on some two-dimensional(2 D)curved surfaces has received increasing attention in the past decade.Here,in light of the Huygens-Fresnel principle,we propose a theoretical frame to study light propagation along arbitrary geodesics on any 2 D curved surfaces.This theory not only enables us to solve the enigma of"infinite intensity"that existed previously at artificial singularities on surfaces of revolution but also makes it possible to study light propagation on arbitrary 2 D curved surfaces.Based on this theory,we investigate the effects of light propagation on a typical surface of revolution,Flamm’s paraboloid,as an example,from which one can understand the behavior of light in the curved geometry of Schwarzschild black holes.Our theory provides a convenient and powerful tool for investigations of radiation in curved space.展开更多
Automobiles are the major contributor to fuel consumption and emission of pollutants. The growth of the vehicle fleet has also placed enormous pressure on China＇s energy supply and environment. Thus sustainable devel...Automobiles are the major contributor to fuel consumption and emission of pollutants. The growth of the vehicle fleet has also placed enormous pressure on China＇s energy supply and environment. Thus sustainable development of the Chinese automotive industry must pay significant attention to fuel-saving and emission-reduction of vehicles. Although commercial vehicles make up only about 20% of the entire automobile fleet, their contribution to energy-consumption and emission of pollutants is significant. Thus, priority should be given to fuel-saving and emission-reduction of commercial vehicles. As a result of concerted efforts by Chinese government, industry and enterprises, great progress has been made in technologies concerning new-energy, intelligent and lightweight auto- mobiles. However, compared with developed countries, the level of lightweighting of commercial vehicles produced in China remains comparably low. This means that great potential for development of lightweight commercial vehicles in China exists and it will be an efficient path towards fuel-saving and emission-reduction.展开更多
Herein,we propose a scheme for the realization of two-dimensional atomic localization in aλ-type three-level atomic medium such that the atom interacts with the two orthogonal standing-wave fields and a probe field.B...Herein,we propose a scheme for the realization of two-dimensional atomic localization in aλ-type three-level atomic medium such that the atom interacts with the two orthogonal standing-wave fields and a probe field.Because of the spatially dependent atom-field interaction,the information about the position of the atom can be obtained by monitoring the probe transmission spectra of the weak probe field for the first time.A single and double sharp localized peaks are observed in the one-wavelength domain.We have theoretically archived high-resolution and high-precision atomic localization within a region smaller thanλ/25×λ/25.The results may have potential applications in the field of nano-lithography and advance laser cooling technology.展开更多
基金supported by the National Natural Science Foundation of China(NSFC)(Grant No.11974309)SMASB acknowledges financial support from China Scholarship Council at Zhejiang University.
文摘Some aspects of atom-field interactions in curved spacetime are reviewed.Of great interest are quantum radiative and entanglement processes arising out of Rindler and black hole spacetimes,which involve the role of Hawking-Unruh and dynamical Casimir effects.Most of the discussion surrounds the radiative part of interactions.For this,we specifically reassess the conventional understandings of atomic radiative transitions and energy level shifts in curved spacetime.We also briefly outline the status quo of entanglement dynamics study in curved spacetime,and highlight literature related to some novel insights,like entanglement harvesting.On one hand,the study of the role played by spacetime curvature in quantum radiative and informational phenomena has implications for fundamental physics,notably the gravity-quantum interface.In particular,one examines the viability of the Equivalence Principle,which is at the heart of Einstein’s general theory of relativity.On the other hand,it can be instructive for manipulating quantum information and light propagation in arbitrary geometries.Some issues related to nonthermal effects of acceleration are also discussed.
基金National Natural Science Foundation of China(11974309,62375241)Israel Science Foundation(1871/15,2074/15,2630/20)United States-Israel Binational Science Foundation(2015694)。
文摘Overcoming the diffraction limit is crucial for obtaining high-resolution images and observing fine microstructures.With this conventional difficulty still puzzling us and the prosperous development of wave dynamics of light interacting with gravitational fields in recent years,how spatial curvature affects the diffraction limit is an attractive and important question.Here we investigate the issue of the diffraction limit and optical resolution on two-dimensional curved space—surfaces of revolution(SORs)with constant or variable spatial curvature.We show that the diffraction limit decreases and the resolution is improved on SORs with positive Gaussian curvature,opening a new avenue to super-resolution.The diffraction limit is also influenced by the propagation direction,as well as the propagation distance in curved space with variable spatial curvature.These results provide a possible method to control the optical resolution in curved space or equivalent waveguides with varying refractive index distribution and may allow one to detect the presence of the nonuniform strong gravitational effect by probing locally the optical resolution.
基金supported by the National Key Research and Development Program of China(2021YFF1000602)the Chinese Academy of Sciences(XDA24010107)+2 种基金the National Natural Science Foundation of China(31750110480)the Animal Branch of the Germplasm Bank of Wild Species,Chinese Academy of Sciences(the Large Research Infrastructure Funding)the Spring City Plan:the High-level Talent Promotion and Training Project of Kunming(2022SCP001)。
文摘Inbreeding depression(ID)refers to the undesirable effects of inbreeding(mating of relatives)on fitness-associated phenotypes(Charlesworth and Willis,2009).ID on production,reproduction,and health traits is relevant to industrial profitability,making it important in animal management.Runs of homozygosity(ROH)is a good measure of inbreeding and autozygosity(the inheritance of two copies of an ancestral allele)(Alkuraya,2013).
基金Natural Science Foundation of Zhejiang Province,China(LD18A040001)National Natural Science Foundation of China(11974309,11674284)National Key Research and Development Program of China(2017YFA0304202)。
文摘As an analog model of general relativity,optics on some two-dimensional(2 D)curved surfaces has received increasing attention in the past decade.Here,in light of the Huygens-Fresnel principle,we propose a theoretical frame to study light propagation along arbitrary geodesics on any 2 D curved surfaces.This theory not only enables us to solve the enigma of"infinite intensity"that existed previously at artificial singularities on surfaces of revolution but also makes it possible to study light propagation on arbitrary 2 D curved surfaces.Based on this theory,we investigate the effects of light propagation on a typical surface of revolution,Flamm’s paraboloid,as an example,from which one can understand the behavior of light in the curved geometry of Schwarzschild black holes.Our theory provides a convenient and powerful tool for investigations of radiation in curved space.
文摘Automobiles are the major contributor to fuel consumption and emission of pollutants. The growth of the vehicle fleet has also placed enormous pressure on China＇s energy supply and environment. Thus sustainable development of the Chinese automotive industry must pay significant attention to fuel-saving and emission-reduction of vehicles. Although commercial vehicles make up only about 20% of the entire automobile fleet, their contribution to energy-consumption and emission of pollutants is significant. Thus, priority should be given to fuel-saving and emission-reduction of commercial vehicles. As a result of concerted efforts by Chinese government, industry and enterprises, great progress has been made in technologies concerning new-energy, intelligent and lightweight auto- mobiles. However, compared with developed countries, the level of lightweighting of commercial vehicles produced in China remains comparably low. This means that great potential for development of lightweight commercial vehicles in China exists and it will be an efficient path towards fuel-saving and emission-reduction.
基金supported by the Zhejiang Provincial Natural Science Foundation of China under Grant No.LD18A040001the National Key Research and Development Program of China(No.2017YFA0304202)the National Natural Science Foundation of China(Grant No.11974309)。
文摘Herein,we propose a scheme for the realization of two-dimensional atomic localization in aλ-type three-level atomic medium such that the atom interacts with the two orthogonal standing-wave fields and a probe field.Because of the spatially dependent atom-field interaction,the information about the position of the atom can be obtained by monitoring the probe transmission spectra of the weak probe field for the first time.A single and double sharp localized peaks are observed in the one-wavelength domain.We have theoretically archived high-resolution and high-precision atomic localization within a region smaller thanλ/25×λ/25.The results may have potential applications in the field of nano-lithography and advance laser cooling technology.
