Pub Date : 2024-12-01DOI: 10.1016/j.nuclphysb.2024.116730
Sheldon Lee Glashow
This is a very personal account of the evolution of the Standard Model of Particle Physics, as I experienced it, from the years 1954 to 1976. I highlight the theoretical prediction of the charmed quark and the experimental discovery of the J particle.
{"title":"Charm and the standard model","authors":"Sheldon Lee Glashow","doi":"10.1016/j.nuclphysb.2024.116730","DOIUrl":"10.1016/j.nuclphysb.2024.116730","url":null,"abstract":"<div><div>This is a very personal account of the evolution of the Standard Model of Particle Physics, as I experienced it, from the years 1954 to 1976. I highlight the theoretical prediction of the charmed quark and the experimental discovery of the J particle.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1009 ","pages":"Article 116730"},"PeriodicalIF":2.5,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142757461","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-28DOI: 10.1016/j.nuclphysb.2024.116759
Nishant Gupta , Nemani V. Suryanarayana
Generalising the chiral boundary conditions of gravity for AdS4 gravity, we derive chiral locally AdS4 solutions in the Newman-Unti gauge consistent with a variational principle whose asymptotic symmetry algebra we show, to be an infinite-dimensional chiral extension of . This symmetry algebra coincides with the chiral algebra in the flat space limit with the corresponding solutions mapping to the space of gravitational vacua in gravity. We posit this symmetry algebra as the chiral version of recently discovered Λ- algebra. We propose line integral charges from the bulk AdS4 gravity associated with this asymptotic symmetry algebra and show that they obey the semi-classical limit of a -algebra. We derive this -algebra for finite central charge c and level κ using associativity constraints of 2d CFT and find it to be isomorphic to one of quasi-superconformal algebra that existed in the literature.
{"title":"A chiral Λ-bms4 symmetry of AdS4 gravity","authors":"Nishant Gupta , Nemani V. Suryanarayana","doi":"10.1016/j.nuclphysb.2024.116759","DOIUrl":"10.1016/j.nuclphysb.2024.116759","url":null,"abstract":"<div><div>Generalising the chiral boundary conditions of <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>3</mn></mrow></msup></math></span> gravity for AdS<sub>4</sub> gravity, we derive chiral locally AdS<sub>4</sub> solutions in the Newman-Unti gauge consistent with a variational principle whose asymptotic symmetry algebra we show, to be an infinite-dimensional chiral extension of <span><math><mrow><mi>so</mi></mrow><mo>(</mo><mn>2</mn><mo>,</mo><mn>3</mn><mo>)</mo></math></span>. This symmetry algebra coincides with the chiral <span><math><msub><mrow><mi>bms</mi></mrow><mrow><mn>4</mn></mrow></msub></math></span> algebra in the flat space limit with the corresponding solutions mapping to the space of gravitational vacua in <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>1</mn><mo>,</mo><mn>3</mn></mrow></msup></math></span> gravity. We posit this symmetry algebra as the chiral version of recently discovered Λ-<span><math><msub><mrow><mi>bms</mi></mrow><mrow><mn>4</mn></mrow></msub></math></span> algebra. We propose line integral charges from the bulk AdS<sub>4</sub> gravity associated with this asymptotic symmetry algebra and show that they obey the semi-classical limit of a <span><math><mi>W</mi></math></span>-algebra. We derive this <span><math><mi>W</mi></math></span>-algebra for finite central charge <em>c</em> and level <em>κ</em> using associativity constraints of 2<em>d</em> CFT and find it to be isomorphic to one of quasi-superconformal algebra that existed in the literature.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116759"},"PeriodicalIF":2.5,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747764","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-26DOI: 10.1016/j.nuclphysb.2024.116754
E.V. Arbuzova , A.D. Dolgov , A.A. Nikitenko
The origin of the ultra high energy cosmic rays via annihilation of heavy stable, fermions “f”, of the cosmological dark matter (DM) is studied. The particles in question are supposed to be created by the scalaron decays in modified gravity. The novel part of our approach is the assumption that the mass of these carriers of DM is slightly below than a half of the scalaron mass. In such a case the phase space volume becomes tiny. It leads to sufficiently low probability of “f” production, so their average cosmological energy density could be equal to the observed energy density of dark matter. Several regions of the universe, where the annihilation could take place, are studied. They include the whole universe under the assumption of homogeneous energy density, the high density DM clump in the galactic center, the cloud of DM in the Galaxy with realistic density distribution, and high density clumps of DM in the Galaxy. Possible resonance annihilation of into energetic light particles is considered. We have shown that the proposed scenario can successfully explain the origin of the ultrahigh energy flux of cosmic rays where canonical astrophysical mechanisms are not operative.
{"title":"Cosmic rays from annihilation of heavy dark matter particles","authors":"E.V. Arbuzova , A.D. Dolgov , A.A. Nikitenko","doi":"10.1016/j.nuclphysb.2024.116754","DOIUrl":"10.1016/j.nuclphysb.2024.116754","url":null,"abstract":"<div><div>The origin of the ultra high energy cosmic rays via annihilation of heavy stable, fermions “f”, of the cosmological dark matter (DM) is studied. The particles in question are supposed to be created by the scalaron decays in <span><math><msup><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></msup></math></span> modified gravity. The novel part of our approach is the assumption that the mass of these carriers of DM is slightly below than a half of the scalaron mass. In such a case the phase space volume becomes tiny. It leads to sufficiently low probability of “f” production, so their average cosmological energy density could be equal to the observed energy density of dark matter. Several regions of the universe, where the annihilation could take place, are studied. They include the whole universe under the assumption of homogeneous energy density, the high density DM clump in the galactic center, the cloud of DM in the Galaxy with realistic density distribution, and high density clumps of DM in the Galaxy. Possible resonance annihilation of <span><math><mi>f</mi><mover><mrow><mi>f</mi></mrow><mrow><mo>¯</mo></mrow></mover></math></span> into energetic light particles is considered. We have shown that the proposed scenario can successfully explain the origin of the ultrahigh energy flux of cosmic rays where canonical astrophysical mechanisms are not operative.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116754"},"PeriodicalIF":2.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-26DOI: 10.1016/j.nuclphysb.2024.116755
Carlo Cafaro , Leonardo Rossetti , Paul M. Alsing
We study the complexity of both time-optimal and time sub-optimal quantum Hamiltonian evolutions connecting arbitrary source and a target states on the Bloch sphere equipped with the Fubini-Study metric. This investigation is performed in a number of steps. First, we describe each unitary Schrödinger quantum evolution by means of the path length, the geodesic efficiency, the speed efficiency, and the curvature coefficient of its corresponding dynamical trajectory linking the source state to the target state. Second, starting from a classical probabilistic setting where the so-called information geometric complexity can be employed to describe the complexity of entropic motion on curved statistical manifolds underlying the physics of systems when only partial knowledge about them is available, we transition into a deterministic quantum setting. In this context, after proposing a definition of the complexity of a quantum evolution, we present a notion of quantum complexity length scale. In particular, we discuss the physical significance of both quantities in terms of the accessed (i.e., partial) and accessible (i.e., total) parametric volumes of the regions on the Bloch sphere that specify the quantum mechanical evolution from the source to the target states. Third, after calculating the complexity measure and the complexity length scale for each one of the two quantum evolutions, we compare the behavior of our measures with that of the path length, the geodesic efficiency, the speed efficiency, and the curvature coefficient. We find that, in general, efficient quantum evolutions are less complex than inefficient evolutions. However, we also observe that complexity is more than length. Indeed, longer paths that are sufficiently bent can exhibit a behavior that is less complex than that of shorter paths with a smaller curvature coefficient.
{"title":"Complexity of quantum-mechanical evolutions from probability amplitudes","authors":"Carlo Cafaro , Leonardo Rossetti , Paul M. Alsing","doi":"10.1016/j.nuclphysb.2024.116755","DOIUrl":"10.1016/j.nuclphysb.2024.116755","url":null,"abstract":"<div><div>We study the complexity of both time-optimal and time sub-optimal quantum Hamiltonian evolutions connecting arbitrary source and a target states on the Bloch sphere equipped with the Fubini-Study metric. This investigation is performed in a number of steps. First, we describe each unitary Schrödinger quantum evolution by means of the path length, the geodesic efficiency, the speed efficiency, and the curvature coefficient of its corresponding dynamical trajectory linking the source state to the target state. Second, starting from a classical probabilistic setting where the so-called information geometric complexity can be employed to describe the complexity of entropic motion on curved statistical manifolds underlying the physics of systems when only partial knowledge about them is available, we transition into a deterministic quantum setting. In this context, after proposing a definition of the complexity of a quantum evolution, we present a notion of quantum complexity length scale. In particular, we discuss the physical significance of both quantities in terms of the accessed (i.e., partial) and accessible (i.e., total) parametric volumes of the regions on the Bloch sphere that specify the quantum mechanical evolution from the source to the target states. Third, after calculating the complexity measure and the complexity length scale for each one of the two quantum evolutions, we compare the behavior of our measures with that of the path length, the geodesic efficiency, the speed efficiency, and the curvature coefficient. We find that, in general, efficient quantum evolutions are less complex than inefficient evolutions. However, we also observe that complexity is more than length. Indeed, longer paths that are sufficiently bent can exhibit a behavior that is less complex than that of shorter paths with a smaller curvature coefficient.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116755"},"PeriodicalIF":2.5,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720376","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-22DOI: 10.1016/j.nuclphysb.2024.116751
J.S. Gonçalves, A.F. Santos
In this paper, gravity is considered. It is a generalization of the theories and . This modified theory of gravity exhibits strong geometry-matter coupling. The problem of causality and its violation is verified in this model. Such analysis is carried out using Gödel-type solutions considering different types of matter. It is shown that this model allows both causal and non-causal solutions. These solutions depend directly on the content of matter present in the universe. For the non-causal solution, a critical radius is calculated, beyond which causality is violated. Taking different matter contents, an infinite critical radius emerges that leads to a causal solution. To obtain a causal solution, a natural relationship arises between the parameters of the theory.
{"title":"On causality and its violation in f(R,Lm,T) gravity","authors":"J.S. Gonçalves, A.F. Santos","doi":"10.1016/j.nuclphysb.2024.116751","DOIUrl":"10.1016/j.nuclphysb.2024.116751","url":null,"abstract":"<div><div>In this paper, <span><math><mi>f</mi><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>,</mo><mi>T</mi><mo>)</mo></math></span> gravity is considered. It is a generalization of the theories <span><math><mi>f</mi><mo>(</mo><mi>R</mi><mo>,</mo><mi>T</mi><mo>)</mo></math></span> and <span><math><mi>f</mi><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>)</mo></math></span>. This modified theory of gravity exhibits strong geometry-matter coupling. The problem of causality and its violation is verified in this model. Such analysis is carried out using Gödel-type solutions considering different types of matter. It is shown that this model allows both causal and non-causal solutions. These solutions depend directly on the content of matter present in the universe. For the non-causal solution, a critical radius is calculated, beyond which causality is violated. Taking different matter contents, an infinite critical radius emerges that leads to a causal solution. To obtain a causal solution, a natural relationship arises between the parameters of the theory.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116751"},"PeriodicalIF":2.5,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We investigate the role of a linear barotropic equation of state () on the structure of charged stars under higher curvature effects induced by the Gauss-Bonnet invariants in 4 dimensions. Assuming a constant spatially directed potential which gives isothermal behavior in the standard theory, the master equation is solved in terms of hypergeometric functions but a viable model could not be constructed. Setting the temporal potential to a constant, comparable to the defective Einstein static universe, interestingly admits nontrivial nonconstant exact solutions due to the higher curvature terms unlike in general relativity. Next the existence of a one-parameter group of conformal motions in the spacetime geometry was investigated. The master differential equation is solvable exactly in implicit form and explicit solutions are found for special cases. For the case of a stiff fluid a stellar model with pleasing physical attributes is found. When the potential is assumed to vary linearly with the radius, an exact incoherent radiation model emerges. The physical properties of both these solutions are analyzed comprehensively with the aid of graphical plots in conjunction with suitably defined parameter spaces. It was found that both exact models passed elementary astrophysical tests for physical plausibility.
{"title":"Barotropic equations of state in 4D Einstein-Maxwell-Gauss-Bonnet stellar distributions","authors":"Sudan Hansraj, Siyamthanda Remember Mngadi, Abdelghani Errehymy","doi":"10.1016/j.nuclphysb.2024.116753","DOIUrl":"10.1016/j.nuclphysb.2024.116753","url":null,"abstract":"<div><div>We investigate the role of a linear barotropic equation of state (<span><math><mi>p</mi><mo>=</mo><mi>γ</mi><mi>ρ</mi></math></span>) on the structure of charged stars under higher curvature effects induced by the Gauss-Bonnet invariants in 4 dimensions. Assuming a constant spatially directed potential which gives isothermal behavior in the standard theory, the master equation is solved in terms of hypergeometric functions but a viable model could not be constructed. Setting the temporal potential to a constant, comparable to the defective Einstein static universe, interestingly admits nontrivial nonconstant exact solutions due to the higher curvature terms unlike in general relativity. Next the existence of a one-parameter group of conformal motions in the spacetime geometry was investigated. The master differential equation is solvable exactly in implicit form and explicit solutions are found for special cases. For the case of a stiff fluid <span><math><mi>p</mi><mo>=</mo><mi>ρ</mi></math></span> a stellar model with pleasing physical attributes is found. When the potential is assumed to vary linearly with the radius, an exact incoherent radiation model <span><math><mi>p</mi><mo>=</mo><mfrac><mrow><mn>1</mn></mrow><mrow><mn>3</mn></mrow></mfrac><mi>ρ</mi></math></span> emerges. The physical properties of both these solutions are analyzed comprehensively with the aid of graphical plots in conjunction with suitably defined parameter spaces. It was found that both exact models passed elementary astrophysical tests for physical plausibility.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116753"},"PeriodicalIF":2.5,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-22DOI: 10.1016/j.nuclphysb.2024.116752
Hang Zhou , Ning Liu
Electroweak scale higgsinos with a nearly degenerate spectrum in supersymmetric models are well-motivated, but generally less constrained at collider experiments as the decay products are often too soft to detect. Initial photon fusions alongside the collision of protons at the Large Hadron Collider (LHC) have drawn attention recently as a way to search for new physics with such kind of spectra. In this paper, we demonstrate a search strategy for chargino pair production from photon fusion at the 13 TeV LHC via the semileptonic decay channel, as a probe for the compressed spectra of higgsinos. Forward detectors make it possible to detect the outgoing protons after emitting the initial photons in these processes. We here provide simple event selections on missing energy and transverse momentum of leptons, which are effective enough to reach significant sensitivity. The chargino mass can be excluded at 95% C.L. up to about 295 GeV with the mass difference being only a few GeV with the integrated luminosity of 3 ab−1. With a relatively small luminosity of 100 fb−1, the 2σ exclusion bounds can as well exceed current experimental limits in the range of GeV, reaching over 190 GeV for chargino mass.
{"title":"Search for nearly degenerate higgsinos via photon fusion with the semileptonic channel at the LHC","authors":"Hang Zhou , Ning Liu","doi":"10.1016/j.nuclphysb.2024.116752","DOIUrl":"10.1016/j.nuclphysb.2024.116752","url":null,"abstract":"<div><div>Electroweak scale higgsinos with a nearly degenerate spectrum in supersymmetric models are well-motivated, but generally less constrained at collider experiments as the decay products are often too soft to detect. Initial photon fusions alongside the collision of protons at the Large Hadron Collider (LHC) have drawn attention recently as a way to search for new physics with such kind of spectra. In this paper, we demonstrate a search strategy for chargino pair production from photon fusion <span><math><mi>p</mi><mi>p</mi><mo>→</mo><mi>p</mi><mo>(</mo><mi>γ</mi><mi>γ</mi><mo>→</mo><msubsup><mrow><mover><mrow><mi>χ</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mn>1</mn></mrow><mrow><mo>+</mo></mrow></msubsup><msubsup><mrow><mover><mrow><mi>χ</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mn>1</mn></mrow><mrow><mo>−</mo></mrow></msubsup><mo>)</mo><mi>p</mi></math></span> at the 13<!--> <!-->TeV LHC via the semileptonic decay channel, as a probe for the compressed spectra of higgsinos. Forward detectors make it possible to detect the outgoing protons after emitting the initial photons in these processes. We here provide simple event selections on missing energy and transverse momentum of leptons, which are effective enough to reach significant sensitivity. The chargino mass can be excluded at 95% C.L. up to about 295<!--> <!-->GeV with the mass difference <span><math><mi>Δ</mi><mi>m</mi><mo>(</mo><msubsup><mrow><mover><mrow><mi>χ</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mn>1</mn></mrow><mrow><mo>±</mo></mrow></msubsup><mo>,</mo><msubsup><mrow><mover><mrow><mi>χ</mi></mrow><mrow><mo>˜</mo></mrow></mover></mrow><mrow><mn>1</mn></mrow><mrow><mn>0</mn></mrow></msubsup><mo>)</mo></math></span> being only a few GeV with the integrated luminosity of 3<!--> <!-->ab<sup>−1</sup>. With a relatively small luminosity of 100<!--> <!-->fb<sup>−1</sup>, the 2<em>σ</em> exclusion bounds can as well exceed current experimental limits in the range of <span><math><mi>Δ</mi><mi>m</mi><mo>=</mo><mn>1</mn><mo>∼</mo><mn>2</mn></math></span> <!-->GeV, reaching over 190<!--> <!-->GeV for chargino mass.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116752"},"PeriodicalIF":2.5,"publicationDate":"2024-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-20DOI: 10.1016/j.nuclphysb.2024.116749
M. Umair Shahzad , Nazek Alessa , Aqsa Mehmood , Muhammad Zeshan Ashraf
The study of topology opens a new frontier in understanding the characteristics of light rings in rotating black holes, as well as the equatorial timelike circular orbits found in non-rotating black holes. This work is devoted to exploring the configurations of circular orbits within the temporal dimension, characterized by the different topology in regular black holes, and determining the corresponding zero points. Using effective potential, we built the vector in the r-θ plane where the zeros of ϕ define location of the timelike circular orbits. This special feature allows one to relate timelike circular orbits with the topology. To each zero point of the vector it is possible to assign a winding number, which defines a topological characteristic for timelike circular orbits. Winding numbers of -1 and +1 are assigned for unstable and stable timelike circular orbits respectively.
{"title":"Topological arrangements in the equatorial timelike circular orbits of regular black holes","authors":"M. Umair Shahzad , Nazek Alessa , Aqsa Mehmood , Muhammad Zeshan Ashraf","doi":"10.1016/j.nuclphysb.2024.116749","DOIUrl":"10.1016/j.nuclphysb.2024.116749","url":null,"abstract":"<div><div>The study of topology opens a new frontier in understanding the characteristics of light rings in rotating black holes, as well as the equatorial timelike circular orbits found in non-rotating black holes. This work is devoted to exploring the configurations of circular orbits within the temporal dimension, characterized by the different topology in regular black holes, and determining the corresponding zero points. Using effective potential, we built the vector in the <em>r</em>-<em>θ</em> plane where the zeros of <em>ϕ</em> define location of the timelike circular orbits. This special feature allows one to relate timelike circular orbits with the topology. To each zero point of the vector it is possible to assign a winding number, which defines a topological characteristic for timelike circular orbits. Winding numbers of -1 and +1 are assigned for unstable and stable timelike circular orbits respectively.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116749"},"PeriodicalIF":2.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142720375","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-20DOI: 10.1016/j.nuclphysb.2024.116744
Joanna Piwnik, Joanna Gonera, Piotr Kosiński
New form of Fermat's principle for light propagation in arbitrary (i.e. in general neither static nor stationary) gravitational field is proposed. It is based on Herglotz extension of canonical formalism and simple relation between the dynamics described by the Lagrangians homogeneous in velocities and the reduced dynamics on lower-dimensional configuration manifold. This approach is more flexible as it allows to extend immediately the Fermat principle to the case of massive particles and to eliminate any space-time coordinate, not only .
{"title":"Fermat's principle in general relativity via Herglotz variational formalism","authors":"Joanna Piwnik, Joanna Gonera, Piotr Kosiński","doi":"10.1016/j.nuclphysb.2024.116744","DOIUrl":"10.1016/j.nuclphysb.2024.116744","url":null,"abstract":"<div><div>New form of Fermat's principle for light propagation in arbitrary (i.e. in general neither static nor stationary) gravitational field is proposed. It is based on Herglotz extension of canonical formalism and simple relation between the dynamics described by the Lagrangians homogeneous in velocities and the reduced dynamics on lower-dimensional configuration manifold. This approach is more flexible as it allows to extend immediately the Fermat principle to the case of massive particles and to eliminate any space-time coordinate, not only <span><math><msup><mrow><mi>x</mi></mrow><mrow><mn>0</mn></mrow></msup></math></span>.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1010 ","pages":"Article 116744"},"PeriodicalIF":2.5,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-11-19DOI: 10.1016/j.nuclphysb.2024.116750
Narges Heidari , Marc de Montigny , Ali Ahmadi Azar , Thambiayya Sathiyaraj , Hassan Hassanabadi
Motivated by the prediction of a minimal measurable length at Planck scale found in many candidate theories of quantum gravity, we examine the Klein-Gordon equation with a interaction and a symmetry-breaking term, in the presence of a generalized uncertainty principle associated with a minimal length. This allows us to assess the correction which underlying physical systems of scalar fields would undergo. Further, we solve the Euler-Lagrange equation by applying the Hybrid Analytical and Numerical (or HAN, for short) method, an effective approach for solving a large variety of nonlinear ordinary and partial differential equations.
{"title":"Solutions of the nonlinear Klein-Gordon equation and the generalized uncertainty principle with the hybrid analytical and numerical method","authors":"Narges Heidari , Marc de Montigny , Ali Ahmadi Azar , Thambiayya Sathiyaraj , Hassan Hassanabadi","doi":"10.1016/j.nuclphysb.2024.116750","DOIUrl":"10.1016/j.nuclphysb.2024.116750","url":null,"abstract":"<div><div>Motivated by the prediction of a minimal measurable length at Planck scale found in many candidate theories of quantum gravity, we examine the Klein-Gordon equation with a <span><math><mi>λ</mi><msup><mrow><mi>ϕ</mi></mrow><mrow><mn>4</mn></mrow></msup></math></span> interaction and a symmetry-breaking term, in the presence of a generalized uncertainty principle associated with a minimal length. This allows us to assess the correction which underlying physical systems of scalar fields would undergo. Further, we solve the Euler-Lagrange equation by applying the <em>Hybrid Analytical and Numerical</em> (or HAN, for short) method, an effective approach for solving a large variety of nonlinear ordinary and partial differential equations.</div></div>","PeriodicalId":54712,"journal":{"name":"Nuclear Physics B","volume":"1009 ","pages":"Article 116750"},"PeriodicalIF":2.5,"publicationDate":"2024-11-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142698712","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
扫码关注我们
求助内容：
应助结果提醒方式：
京公网安备 11010802042870号