Pub Date : 2026-05-01Epub Date: 2026-02-06DOI: 10.1016/j.aop.2026.170385
Samuel B.B. Almeida, J.E.G. Silva, C.A.S. Almeida
We study the influence of a localized Gaussian deformation on massless Dirac fermions confined to a two-dimensional curved surface. Both in-plane and out-of-plane displacements are considered within the framework of elasticity theory. These deformations couple to the Dirac spinors via the spin connection and the vielbeins, leading to a position-dependent Fermi velocity and an effective geometric potential. We show that spin connection modifies the density of states near the origin and how this modification is altered by changing mechanical parameters. Analytical and numerical solutions reveal the emergence of asymptotically free states, but with changes in amplitude near the origin due to the modification of curvature mediated by Lamé coefficients. Upon introducing an external magnetic field, the effective potential becomes confining at large distances, producing localized Landau levels that concentrate near the deformation, thus enabling the evaluation of how mechanical coefficients affect the localization of states. A geometric Aharonov–Bohm phase is identified through the spinor holonomy. These results contribute to the understanding of strain-induced electronic effects in Dirac materials, such as graphene.
{"title":"Dirac fermions on a surface with localized strain","authors":"Samuel B.B. Almeida, J.E.G. Silva, C.A.S. Almeida","doi":"10.1016/j.aop.2026.170385","DOIUrl":"10.1016/j.aop.2026.170385","url":null,"abstract":"<div><div>We study the influence of a localized Gaussian deformation on massless Dirac fermions confined to a two-dimensional curved surface. Both in-plane and out-of-plane displacements are considered within the framework of elasticity theory. These deformations couple to the Dirac spinors via the spin connection and the vielbeins, leading to a position-dependent Fermi velocity and an effective geometric potential. We show that spin connection modifies the density of states near the origin and how this modification is altered by changing mechanical parameters. Analytical and numerical solutions reveal the emergence of asymptotically free states, but with changes in amplitude near the origin due to the modification of curvature mediated by Lamé coefficients. Upon introducing an external magnetic field, the effective potential becomes confining at large distances, producing localized Landau levels that concentrate near the deformation, thus enabling the evaluation of how mechanical coefficients affect the localization of states. A geometric Aharonov–Bohm phase is identified through the spinor holonomy. These results contribute to the understanding of strain-induced electronic effects in Dirac materials, such as graphene.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170385"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We present a unified geometric and dynamical framework to investigate a two-spin system governed by the XXX Heisenberg model in the presence of an external magnetic field and an additional anisotropic KSEA exchange interaction. Using the Fubini–Study formalism, we derive the metric tensor of the corresponding quantum state space and compute the related Gaussian curvature. Our analysis reveals that the system evolves on a closed, anisotropic two-dimensional manifold embedded in , whose geometry is tuned by interaction strengths, with a topological redundancy emerging during the system’s dynamics. We also examine the geometric phase for arbitrary and cyclic evolutions, identifying the KSEA interaction as the primary factor shaping its behavior. We investigate quantum dynamics through evolution speed, Fubini–Study distance, and the brachistochrone problem, finding that stronger KSEA coupling or a more intense magnetic field reduces the optimal evolution time, thereby accelerating state transformations. Entanglement, quantified by the concurrence measure, is stabilized through KSEA coupling and enhanced by the magnetic field. From a geometric perspective, entanglement reshapes the curvature and geometric phase accumulation, while from a dynamical perspective it accelerates evolution and lengthens geodesic paths between the two-spin states. Finally, our analysis is applied to the concrete task of quantum teleportation, where we show that teleportation fidelity is closely related to the Gaussian curvature, geometric phase, speed, Fubini–Study distance, and brachistochrone time, and that fine-tuning the KSEA coupling significantly enhances teleportation performance.
{"title":"Fubini–Study geometry, dynamics, and entanglement in KSEA-coupled two-spin system under magnetic field: Implications for quantum teleportation","authors":"Brahim Amghar , Mouhcine Yachi , M’bark Amghar , Abdallah Slaoui","doi":"10.1016/j.aop.2026.170386","DOIUrl":"10.1016/j.aop.2026.170386","url":null,"abstract":"<div><div>We present a unified geometric and dynamical framework to investigate a two-spin system governed by the XXX Heisenberg model in the presence of an external magnetic field and an additional anisotropic KSEA exchange interaction. Using the Fubini–Study formalism, we derive the metric tensor of the corresponding quantum state space and compute the related Gaussian curvature. Our analysis reveals that the system evolves on a closed, anisotropic two-dimensional manifold embedded in <span><math><mrow><mi>ℂ</mi><msup><mrow><mi>P</mi></mrow><mrow><mn>3</mn></mrow></msup></mrow></math></span>, whose geometry is tuned by interaction strengths, with a topological redundancy emerging during the system’s dynamics. We also examine the geometric phase for arbitrary and cyclic evolutions, identifying the KSEA interaction as the primary factor shaping its behavior. We investigate quantum dynamics through evolution speed, Fubini–Study distance, and the brachistochrone problem, finding that stronger KSEA coupling or a more intense magnetic field reduces the optimal evolution time, thereby accelerating state transformations. Entanglement, quantified by the concurrence measure, is stabilized through KSEA coupling and enhanced by the magnetic field. From a geometric perspective, entanglement reshapes the curvature and geometric phase accumulation, while from a dynamical perspective it accelerates evolution and lengthens geodesic paths between the two-spin states. Finally, our analysis is applied to the concrete task of quantum teleportation, where we show that teleportation fidelity is closely related to the Gaussian curvature, geometric phase, speed, Fubini–Study distance, and brachistochrone time, and that fine-tuning the KSEA coupling significantly enhances teleportation performance.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170386"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186559","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-05-01Epub Date: 2026-02-12DOI: 10.1016/j.aop.2026.170393
Hamid Mosadeq , Mohammad-Hossein Zare
The layered honeycomb material -RuCl represents a significant candidate for the realization of a Kitaev quantum spin liquid (QSL) due to its pronounced spin–orbit coupling and bond-directional interactions. Experimental observations of a half-quantized thermal Hall effect under applied magnetic fields indicate the potential presence of fractionalized excitations, possibly of Majorana origin. However, the lack of definitive theoretical and experimental consensus necessitates further investigation into related magnetic phases. This study concentrates on the partially polarized ferromagnetic phase of -RuCl, which exhibits critical symmetry features analogous to those of the QSL state and may display comparable topological thermal transport signatures. Utilizing the framework of linear spin-wave theory, we calculate the thermal Hall conductivity () for five representative sets of exchange parameters derived from an extended minimal model. This Hamiltonian incorporates the first-neighbor Heisenberg interaction , the Kitaev interaction , and third-nearest-neighbor Heisenberg interactions , in addition to off-diagonal and terms. Our analysis reveals model-dependent behavior in both the magnitude and sign of , with temperature-dependent sign reversals observed in certain instances. Moreover, we demonstrate that the inclusion of the second-nearest-neighbor Dzyaloshinskii–Moriya (DM) interaction significantly modifies the magnonic Berry curvature and, consequently, the thermal Hall response. These findings provide a theoretical framework for the interpretation of thermal Hall experiments in -RuCl and emphasize the sensitivity of topological magnon transport to the microscopic details of interactions in frustrated quantum magnets.
{"title":"Theoretical study of topological magnon transport in α-RuCl3: Effects of interactions on thermal Hall conductivity","authors":"Hamid Mosadeq , Mohammad-Hossein Zare","doi":"10.1016/j.aop.2026.170393","DOIUrl":"10.1016/j.aop.2026.170393","url":null,"abstract":"<div><div>The layered honeycomb material <span><math><mi>α</mi></math></span>-RuCl<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> represents a significant candidate for the realization of a Kitaev quantum spin liquid (QSL) due to its pronounced spin–orbit coupling and bond-directional interactions. Experimental observations of a half-quantized thermal Hall effect under applied magnetic fields indicate the potential presence of fractionalized excitations, possibly of Majorana origin. However, the lack of definitive theoretical and experimental consensus necessitates further investigation into related magnetic phases. This study concentrates on the partially polarized ferromagnetic phase of <span><math><mi>α</mi></math></span>-RuCl<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span>, which exhibits critical symmetry features analogous to those of the QSL state and may display comparable topological thermal transport signatures. Utilizing the framework of linear spin-wave theory, we calculate the thermal Hall conductivity (<span><math><msubsup><mrow><mi>κ</mi></mrow><mrow><mi>TH</mi></mrow><mrow><mi>x</mi><mi>y</mi></mrow></msubsup></math></span>) for five representative sets of exchange parameters derived from an extended minimal <span><math><mrow><mi>K</mi><mi>J</mi><mi>Γ</mi><msup><mrow><mi>Γ</mi></mrow><mrow><mo>′</mo></mrow></msup><mi>J</mi><mn>3</mn></mrow></math></span> model. This Hamiltonian incorporates the first-neighbor Heisenberg interaction <span><math><mrow><mo>(</mo><mi>J</mi><mo>)</mo></mrow></math></span>, the Kitaev interaction <span><math><mrow><mo>(</mo><mi>K</mi><mo>)</mo></mrow></math></span>, and third-nearest-neighbor Heisenberg interactions <span><math><mrow><mo>(</mo><msub><mrow><mi>J</mi></mrow><mrow><mn>3</mn></mrow></msub><mo>)</mo></mrow></math></span>, in addition to off-diagonal <span><math><mi>Γ</mi></math></span> and <span><math><msup><mrow><mi>Γ</mi></mrow><mrow><mo>′</mo></mrow></msup></math></span> terms. Our analysis reveals model-dependent behavior in both the magnitude and sign of <span><math><msubsup><mrow><mi>κ</mi></mrow><mrow><mi>TH</mi></mrow><mrow><mi>x</mi><mi>y</mi></mrow></msubsup></math></span>, with temperature-dependent sign reversals observed in certain instances. Moreover, we demonstrate that the inclusion of the second-nearest-neighbor Dzyaloshinskii–Moriya (DM) interaction significantly modifies the magnonic Berry curvature and, consequently, the thermal Hall response. These findings provide a theoretical framework for the interpretation of thermal Hall experiments in <span><math><mi>α</mi></math></span>-RuCl<span><math><msub><mrow></mrow><mrow><mn>3</mn></mrow></msub></math></span> and emphasize the sensitivity of topological magnon transport to the microscopic details of interactions in frustrated quantum magnets.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170393"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-05-01Epub Date: 2026-02-07DOI: 10.1016/j.aop.2026.170390
Archana Dixit , Saurabh Verma , Anirudh Pradhan , M.S. Barak
This study investigates and compares two prominent two-dimensional dark energy (DE) parameterizations: Barboza–Alcaniz (BA) and Logarithmic forms by comparing them with a comprehensive set of observational data comprising Type Ia Supernovae (SNe Ia) from the Pantheon compilation, Baryon Acoustic Oscillations (DESI BAO), and Cosmic Chronometers (CC). The primary objective was to explore the constraining power and cosmological implications of each parameterization in light of the current data. After formulating the theoretical framework and background equations governing cosmic expansion, we employ Markov Chain Monte Carlo (MCMC) techniques using the emcee Python package to constrain the free parameters of each model. The best-fit values for parameters , , and were extracted for each model using individual and combined datasets. The results include confidence contours at the levels and . Our findings demonstrate that both parameterizations are consistent with observational data, with logarithmic parameterization showing slightly better constraints in terms of parameter evolution. Furthermore, we employed a statefinder diagnostic to analyze the geometric behavior of the models, providing an effective distinction between the two DE scenarios. This study contributes to a deeper understanding of DE evolution and its constraints in light of current cosmological data.
{"title":"Observational constraints and geometric diagnostics of Barboza–Alcaniz and logarithmic dark energy parametrizations","authors":"Archana Dixit , Saurabh Verma , Anirudh Pradhan , M.S. Barak","doi":"10.1016/j.aop.2026.170390","DOIUrl":"10.1016/j.aop.2026.170390","url":null,"abstract":"<div><div>This study investigates and compares two prominent two-dimensional dark energy (DE) parameterizations: Barboza–Alcaniz (BA) and Logarithmic forms by comparing them with a comprehensive set of observational data comprising Type Ia Supernovae (SNe Ia) from the Pantheon compilation, Baryon Acoustic Oscillations (DESI BAO), and Cosmic Chronometers (CC). The primary objective was to explore the constraining power and cosmological implications of each parameterization in light of the current data. After formulating the theoretical framework and background equations governing cosmic expansion, we employ Markov Chain Monte Carlo (MCMC) techniques using the emcee Python package to constrain the free parameters of each model. The best-fit values for parameters <span><math><msub><mrow><mi>ω</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span>, <span><math><msub><mrow><mi>ω</mi></mrow><mrow><mi>a</mi></mrow></msub></math></span>, and <span><math><msub><mrow><mi>H</mi></mrow><mrow><mn>0</mn></mrow></msub></math></span> were extracted for each model using individual and combined datasets. The results include confidence contours at the levels <span><math><mrow><mn>1</mn><mi>σ</mi></mrow></math></span> and <span><math><mrow><mn>2</mn><mi>σ</mi></mrow></math></span>. Our findings demonstrate that both parameterizations are consistent with observational data, with logarithmic parameterization showing slightly better constraints in terms of parameter evolution. Furthermore, we employed a statefinder diagnostic to analyze the geometric behavior of the models, providing an effective distinction between the two DE scenarios. This study contributes to a deeper understanding of DE evolution and its constraints in light of current cosmological data.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170390"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186558","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-05-01Epub Date: 2026-02-10DOI: 10.1016/j.aop.2026.170381
Leonardo P.G. De Assis
The consistent embedding of Loop Quantum Gravity (LQG) effects within the Standard Model requires a rigorous understanding of how Planck-scale deformations manifest at low energies. While phenomenological approaches often introduce canonical deformations with multiple free parameters to capture these effects, the physical requirement of gauge symmetry in the framework of a covariant Effective Field Theory (EFT) imposes strict conditions on the allowed interaction structure. In this paper, we demonstrate that these conditions act as physical selection rules for admissible quantum gravity models. By applying non-Abelian Ward identities and a covariant operator mapping to the dimension-six operator basis, we derive a fundamental on-shell equivalence between kinetic and cubic interaction terms. As a paradigmatic application, we show that the Levy–Helayël-Neto (LHN) framework – a candidate effective description of LQG – satisfies this physical requirement only when its parameters obey the specific algebraic relation: It must be highlighted that this result advances the physical understanding of LQG phenomenology by revealing that the apparent freedom in defining the Hamiltonian is illusory; the parameters are bound by the necessity of preserving the gauge structure of the Standard Model.
{"title":"Revealing gauge constraints in LQG-inspired Yang–Mills theory","authors":"Leonardo P.G. De Assis","doi":"10.1016/j.aop.2026.170381","DOIUrl":"10.1016/j.aop.2026.170381","url":null,"abstract":"<div><div>The consistent embedding of Loop Quantum Gravity (LQG) effects within the Standard Model requires a rigorous understanding of how Planck-scale deformations manifest at low energies. While phenomenological approaches often introduce canonical deformations with multiple free parameters to capture these effects, the physical requirement of gauge symmetry in the framework of a covariant Effective Field Theory (EFT) imposes strict conditions on the allowed interaction structure. In this paper, we demonstrate that these conditions act as physical selection rules for admissible quantum gravity models. By applying non-Abelian Ward identities and a covariant operator mapping to the dimension-six operator basis, we derive a fundamental on-shell equivalence between kinetic and cubic interaction terms. As a paradigmatic application, we show that the Levy–Helayël-Neto (LHN) framework – a candidate effective description of LQG – satisfies this physical requirement only when its parameters obey the specific algebraic relation: <span><span><span><math><mrow><mfrac><mrow><msub><mrow><mi>θ</mi></mrow><mrow><mn>3</mn></mrow></msub></mrow><mrow><msub><mrow><mi>θ</mi></mrow><mrow><mn>8</mn></mrow></msub></mrow></mfrac><mo>=</mo><mo>−</mo><mfrac><mrow><mn>1</mn></mrow><mrow><mn>2</mn></mrow></mfrac><mspace></mspace><mfenced><mrow><mn>1</mn><mo>+</mo><msub><mrow><mi>θ</mi></mrow><mrow><mn>7</mn></mrow></msub><msup><mrow><mrow><mo>(</mo><mrow><mfrac><mrow><msub><mrow><mi>ℓ</mi></mrow><mrow><mi>P</mi></mrow></msub></mrow><mrow><mi>L</mi></mrow></mfrac></mrow><mo>)</mo></mrow></mrow><mrow><mn>2</mn><mo>+</mo><mn>2</mn><mi>Υ</mi></mrow></msup></mrow></mfenced><mo>+</mo><mi>O</mi><mrow><mo>(</mo><msub><mrow><mi>ℓ</mi></mrow><mrow><mi>P</mi></mrow></msub><mo>)</mo></mrow><mo>.</mo></mrow></math></span></span></span>It must be highlighted that this result advances the physical understanding of LQG phenomenology by revealing that the apparent freedom in defining the Hamiltonian is illusory; the parameters are bound by the necessity of preserving the gauge structure of the Standard Model.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170381"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186556","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-05-01Epub Date: 2026-02-05DOI: 10.1016/j.aop.2026.170369
Jiafeng Guo , A. Eid , Faisal Javed , M. Zeeshan Gul , Javlon Rayimbaev , Munisbek Akhmedov , N. Mustapha , Yunus Turaev
This analysis focuses on the understanding of the thermodynamic, quantum, and dynamical properties of charged black holes (BHs) in the context of scalar–tensor–vector gravity (STVG). Considering the effect of the MOG parameter () and the electric charge , we discuss how modified gravity affects the stability of BHs, the phase transitions, and the geometry of the spacetime around the BHs. Thermodynamic analysis through the heat capacity, entropy, and free energy shows the presence of multiple stability phases, where larger values lead to an enhancement of quantum fluctuations and a larger alteration of the equilibration, and where values lead to a thermodynamic stabilization. The thermodynamic analysis also shows the effect of higher-order entropy correction terms resulting important quantum effects surrounding the event horizon. The analysis of Hawking emission shows the radiation gets weaker with larger Q values and gets stronger with larger values. This highlights a competition between electromagnetic suppression and gravitational amplification. Also, perturbation theory analysis shows scalar and electromagnetic perturbation with and Q diminishing transmission probabilities by enlarging the effective potential barrier. Geodesic deviation and tidal analysis shows weaker coupling and radial symmetrical perturbation. In summary, the findings indicate that STVG demonstrates a greater range of thermodynamic behavior and more pronounced curvature effects relative to General Relativity (GR). This provides a deeper understanding of the thermodynamics of BHs, not only from STVG perspectives but also from other frameworks of modified gravity.
{"title":"Thermal fluctuation and tidal force of scalar tensor–vector gravity charged black hole","authors":"Jiafeng Guo , A. Eid , Faisal Javed , M. Zeeshan Gul , Javlon Rayimbaev , Munisbek Akhmedov , N. Mustapha , Yunus Turaev","doi":"10.1016/j.aop.2026.170369","DOIUrl":"10.1016/j.aop.2026.170369","url":null,"abstract":"<div><div>This analysis focuses on the understanding of the thermodynamic, quantum, and dynamical properties of charged black holes (BHs) in the context of scalar–tensor–vector gravity (STVG). Considering the effect of the MOG parameter (<span><math><mi>χ</mi></math></span>) and the electric charge <span><math><mrow><mo>(</mo><mi>Q</mi><mo>)</mo></mrow></math></span>, we discuss how modified gravity affects the stability of BHs, the phase transitions, and the geometry of the spacetime around the BHs. Thermodynamic analysis through the heat capacity, entropy, and free energy shows the presence of multiple stability phases, where larger <span><math><mi>χ</mi></math></span> values lead to an enhancement of quantum fluctuations and a larger alteration of the equilibration, and where <span><math><mi>Q</mi></math></span> values lead to a thermodynamic stabilization. The thermodynamic analysis also shows the effect of higher-order entropy correction terms resulting important quantum effects surrounding the event horizon. The analysis of Hawking emission shows the radiation gets weaker with larger Q values and gets stronger with larger <span><math><mi>χ</mi></math></span> values. This highlights a competition between electromagnetic suppression and gravitational amplification. Also, perturbation theory analysis shows scalar and electromagnetic perturbation with <span><math><mi>χ</mi></math></span> and Q diminishing transmission probabilities by enlarging the effective potential barrier. Geodesic deviation and tidal analysis shows weaker coupling and radial symmetrical perturbation. In summary, the findings indicate that STVG demonstrates a greater range of thermodynamic behavior and more pronounced curvature effects relative to General Relativity (GR). This provides a deeper understanding of the thermodynamics of BHs, not only from STVG perspectives but also from other frameworks of modified gravity.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170369"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186563","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-05-01Epub Date: 2026-02-05DOI: 10.1016/j.aop.2026.170384
Raj Kumar Das , Arpan Krishna Mitra
We present a novel formulation for the Hubble parameter derived from Newtonian cosmology, incorporating non-commutative fluid dynamics through a deformed Poisson bracket structure. This approach introduces a new cosmological parameter, denoted by , which emerges naturally from the underlying non-commutative framework. It gives rise to a source term in the background fluid continuity equation, thereby leading to an apparent type of matter creation picture through the resulting non-conservation. Remarkably, the resulting Hubble function accounts for the observed accelerated expansion of the universe without invoking any external dark energy component or cosmological constant. Instead, the parameter effectively serves as the driver of acceleration. We further examine the observational constraints on using current cosmological data, including the recent Dark Energy Spectroscopic Instrument(DESI) dataset, demonstrating its viability as an alternative explanation for late-time cosmic acceleration within a non-commutative cosmological model.
{"title":"Non-commutative fluid as an alternative driver of cosmic acceleration: Confronting DESI observations","authors":"Raj Kumar Das , Arpan Krishna Mitra","doi":"10.1016/j.aop.2026.170384","DOIUrl":"10.1016/j.aop.2026.170384","url":null,"abstract":"<div><div>We present a novel formulation for the Hubble parameter derived from Newtonian cosmology, incorporating non-commutative fluid dynamics through a deformed Poisson bracket structure. This approach introduces a new cosmological parameter, denoted by <span><math><mi>σ</mi></math></span>, which emerges naturally from the underlying non-commutative framework. It gives rise to a source term in the background fluid continuity equation, thereby leading to an apparent type of matter creation picture through the resulting non-conservation. Remarkably, the resulting Hubble function accounts for the observed accelerated expansion of the universe without invoking any external dark energy component or cosmological constant. Instead, the parameter <span><math><mi>σ</mi></math></span> effectively serves as the driver of acceleration. We further examine the observational constraints on <span><math><mi>σ</mi></math></span> using current cosmological data, including the recent Dark Energy Spectroscopic Instrument(DESI) dataset, demonstrating its viability as an alternative explanation for late-time cosmic acceleration within a non-commutative cosmological model.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170384"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186148","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-05-01Epub Date: 2026-02-11DOI: 10.1016/j.aop.2026.170389
Robert Wieser , Raúl Sánchez Galán
The spin dynamics of a trimer with Dzyaloshinsky–Moriya (DM) interaction are investigated within a unified Hamiltonian framework that connects quantum-mechanical and semiclassical descriptions. The interpolation between the two regimes is realized by solving the modified Gisin–Schrödinger equation, in which the relative weight of quantum coherence and local mean-field contributions is continuously tuned. The resulting dynamical behavior is analyzed and summarized in a ground state diagram that illustrates how the character of the spin motion evolves from fully quantum to semiclassical as the DM interaction is treated at different levels of approximation. In the last part of the publication, the chiral spin dynamics originally proposed by Da-Wei Wang et al. is examined theoretically, taking into account its behavior at the boundary between quantum and classical physics.
{"title":"Bridging quantum and classical descriptions of spin dynamics in a Dzyaloshinsky–Moriya trimer","authors":"Robert Wieser , Raúl Sánchez Galán","doi":"10.1016/j.aop.2026.170389","DOIUrl":"10.1016/j.aop.2026.170389","url":null,"abstract":"<div><div>The spin dynamics of a trimer with Dzyaloshinsky–Moriya (DM) interaction are investigated within a unified Hamiltonian framework that connects quantum-mechanical and semiclassical descriptions. The interpolation between the two regimes is realized by solving the modified Gisin–Schrödinger equation, in which the relative weight of quantum coherence and local mean-field contributions is continuously tuned. The resulting dynamical behavior is analyzed and summarized in a ground state diagram that illustrates how the character of the spin motion evolves from fully quantum to semiclassical as the DM interaction is treated at different levels of approximation. In the last part of the publication, the chiral spin dynamics originally proposed by Da-Wei Wang et al. is examined theoretically, taking into account its behavior at the boundary between quantum and classical physics.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170389"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186149","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-05-01Epub Date: 2026-02-12DOI: 10.1016/j.aop.2026.170394
S. Rastgoo, F. Parsaei
In the present analysis, we examine the potential existence of generalized wormhole models within the framework of newly developed extended gravity. We investigate both a linear model, , and a non-linear model, , to analyze traversable wormholes. By employing the variational approach, we derive modified versions of the field equations under the influence of an anisotropic matter source. A power-law shape function is applied, resulting in a linear equation of state for both radial and lateral pressures. Furthermore, we explore solutions characterized by a variable equation of state parameter. It was observed that the violation of energy conditions is influenced by the parameters and . A wide range of non-exotic wormhole solutions was discovered, dependent on the specific parameters of the model. We demonstrate that wormholes with power-law shape functions yield solutions that comply with the energy conditions in both linear and non-linear forms of . It is shown that the non-exotic wormhole solutions obtained within this framework are not isotropic.
{"title":"Non-exotic wormholes in f(R,Lm) gravity","authors":"S. Rastgoo, F. Parsaei","doi":"10.1016/j.aop.2026.170394","DOIUrl":"10.1016/j.aop.2026.170394","url":null,"abstract":"<div><div>In the present analysis, we examine the potential existence of generalized wormhole models within the framework of newly developed extended <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>)</mo></mrow></mrow></math></span> gravity. We investigate both a linear model, <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>)</mo></mrow><mo>=</mo><mi>α</mi><mfrac><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></mfrac><mo>+</mo><mi>β</mi><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub></mrow></math></span>, and a non-linear model, <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>)</mo></mrow><mo>=</mo><mfrac><mrow><mi>R</mi></mrow><mrow><mn>2</mn></mrow></mfrac><mo>+</mo><msubsup><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow><mrow><mi>α</mi></mrow></msubsup></mrow></math></span>, to analyze traversable wormholes. By employing the variational approach, we derive modified versions of the field equations under the influence of an anisotropic matter source. A power-law shape function is applied, resulting in a linear equation of state for both radial and lateral pressures. Furthermore, we explore solutions characterized by a variable equation of state parameter. It was observed that the violation of energy conditions is influenced by the parameters <span><math><mi>α</mi></math></span> and <span><math><mi>β</mi></math></span>. A wide range of non-exotic wormhole solutions was discovered, dependent on the specific parameters of the model. We demonstrate that wormholes with power-law shape functions yield solutions that comply with the energy conditions in both linear and non-linear forms of <span><math><mrow><mi>f</mi><mrow><mo>(</mo><mi>R</mi><mo>,</mo><msub><mrow><mi>L</mi></mrow><mrow><mi>m</mi></mrow></msub><mo>)</mo></mrow></mrow></math></span>. It is shown that the non-exotic wormhole solutions obtained within this framework are not isotropic.</div></div>","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"488 ","pages":"Article 170394"},"PeriodicalIF":3.0,"publicationDate":"2026-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146186150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2026-04-01Epub Date: 2026-01-29DOI: 10.1016/j.aop.2026.170364
Ahmed Farag Ali
<div><div>Motivated by Maldacena’s observer-centric formulation of de Sitter physics (Maldacena, 2024), we develop an observer-dependent state-counting framework in Euclidean de Sitter space by modeling the observer as a massive equatorial worldline carrying an SU(3) clock. Starting from the gauge-fixed graviton path integral on <span><math><msup><mrow><mi>S</mi></mrow><mrow><mi>D</mi></mrow></msup></math></span>, we trace the one-loop phase <span><math><msup><mrow><mi>i</mi></mrow><mrow><mi>D</mi><mo>+</mo><mn>2</mn></mrow></msup></math></span> to a finite set of scalar and conformal Killing modes and show that, once the worldline is included, the <span><math><mrow><mo>(</mo><mi>D</mi><mo>−</mo><mn>1</mn><mo>)</mo></mrow></math></span> transverse negative modes cancel the corresponding <span><math><mrow><mo>(</mo><mi>D</mi><mo>−</mo><mn>1</mn><mo>)</mo></mrow></math></span> conformal Killing directions mode by mode. The residual fixed-<span><math><mi>β</mi></math></span> phase from the global conformal factor and reparametrizations is removed by imposing the Hamiltonian constraint <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mtext>patch</mtext></mrow></msub><mo>−</mo><msub><mrow><mi>H</mi></mrow><mrow><mtext>clock</mtext></mrow></msub><mo>−</mo><mi>ν</mi><mo>=</mo><mn>0</mn></mrow></math></span> via a Bromwich inverse Laplace transform, which under explicit complete-monotonicity assumptions yields a real and positive microcanonical density. We stress that this positivity statement is conditional on Assumptions (A1)–(A3) and is established at one loop about the round <span><math><msup><mrow><mi>S</mi></mrow><mrow><mi>D</mi></mrow></msup></math></span> saddle in the probe regime <span><math><mrow><mi>G</mi><msub><mrow><mi>E</mi></mrow><mrow><mi>clock</mi></mrow></msub><mo>/</mo><mi>R</mi><mo>≪</mo><mn>1</mn></mrow></math></span>; a self-consistent backreacting or higher-loop extension is a natural next step. In earlier work (Ali and Ali 2025; Ali 2025) we argued that unbroken SU(3) confinement at <span><math><mrow><mi>T</mi><mo>→</mo><mn>0</mn></mrow></math></span> can account for the observed value of the cosmological constant and for the origin of the fundamental constants <span><math><mrow><mo>(</mo><mo>ħ</mo><mo>,</mo><mi>G</mi><mo>,</mo><mi>c</mi><mo>)</mo></mrow></math></span> as effective couplings fixed by the SU(3) vacuum structure; this makes SU(3) the natural candidate for the internal clock of de Sitter, whose radius and temperature are themselves set by the same cosmological constant. Here that idea is implemented with three explicit SU(3) realizations (qutrit, Cartan weight-lattice, and <span><math><mrow><mi>U</mi><msup><mrow><mrow><mo>(</mo><mn>1</mn><mo>)</mo></mrow></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> rotor), for which the observer-inclusive density of states factorizes into a universal gravity factor, a universal worldline residue, and a clock-dependent SU(3) weight.</div><div><strong>Summary of con
受Maldacena以观察者为中心的德西特物理公式（Maldacena, 2024）的启发，我们通过将观察者建模为携带SU(3)时钟的巨大赤道世界线，在欧几里得德西特空间中开发了一个依赖观察者的状态计数框架。从SD上的规定引力子路径积分出发，我们将单环相位iD+2追踪到标量和共形杀戮模式的有限集合，并证明，一旦世界线被包括在内，（D−1）横向负模一个接一个地抵消了相应的（D−1）共形杀戮方向。通过施加哈密顿约束Hpatch - Hclock - ν=0，通过Bromwich逆变换去除全局共形因子和再参数化的残差固定β相位，该约束在显式完全单调性假设下产生实正微正则密度。我们强调，这种积极的陈述是以假设(A1) - (A3)为条件的，并且是在探测区圆形SD鞍形的一个环路上建立起来的。自一致的反向反应或高循环扩展是自然而然的下一步。在早期的工作（Ali and Ali 2025; Ali 2025）中，我们认为T→0时的不间断SU(3)约束可以解释宇宙学常数的观测值和基本常数（η，G,c）的起源，它们是由SU(3)真空结构固定的有效耦合；这使得SU(3)成为德西特内部时钟的自然候选者，其半径和温度本身是由相同的宇宙常数设定的。在这里，这个想法是通过三种显式SU(3)实现（qutrit， Cartan权重晶格和U(1)2转子）来实现的，其中包含观察者的状态密度被分解为一个万有引力因子，一个万有引力世界线残差和一个依赖时钟的SU(3)权重。捐款摘要。(i)用（D−1）横向n=0世界线模确定（D−1）赤道移动共形消杀方向，给出一个模对模的准单回路相位消去；（ii）世界线决定因素的双重评估（残余/热核提取和Gel 'fand-Yaglom检查）；（iii）三个SU(3)时钟模型的封闭形式配分函数。微正则密度的现实性和非负性取决于第7节中的显式谱假设(A1) - (A3)，包括β0=2π附近条的可解析性和相位剥离斑块配分函数的完全单调性。
{"title":"Relational de Sitter state counting with an SU(3) clock","authors":"Ahmed Farag Ali","doi":"10.1016/j.aop.2026.170364","DOIUrl":"10.1016/j.aop.2026.170364","url":null,"abstract":"<div><div>Motivated by Maldacena’s observer-centric formulation of de Sitter physics (Maldacena, 2024), we develop an observer-dependent state-counting framework in Euclidean de Sitter space by modeling the observer as a massive equatorial worldline carrying an SU(3) clock. Starting from the gauge-fixed graviton path integral on <span><math><msup><mrow><mi>S</mi></mrow><mrow><mi>D</mi></mrow></msup></math></span>, we trace the one-loop phase <span><math><msup><mrow><mi>i</mi></mrow><mrow><mi>D</mi><mo>+</mo><mn>2</mn></mrow></msup></math></span> to a finite set of scalar and conformal Killing modes and show that, once the worldline is included, the <span><math><mrow><mo>(</mo><mi>D</mi><mo>−</mo><mn>1</mn><mo>)</mo></mrow></math></span> transverse negative modes cancel the corresponding <span><math><mrow><mo>(</mo><mi>D</mi><mo>−</mo><mn>1</mn><mo>)</mo></mrow></math></span> conformal Killing directions mode by mode. The residual fixed-<span><math><mi>β</mi></math></span> phase from the global conformal factor and reparametrizations is removed by imposing the Hamiltonian constraint <span><math><mrow><msub><mrow><mi>H</mi></mrow><mrow><mtext>patch</mtext></mrow></msub><mo>−</mo><msub><mrow><mi>H</mi></mrow><mrow><mtext>clock</mtext></mrow></msub><mo>−</mo><mi>ν</mi><mo>=</mo><mn>0</mn></mrow></math></span> via a Bromwich inverse Laplace transform, which under explicit complete-monotonicity assumptions yields a real and positive microcanonical density. We stress that this positivity statement is conditional on Assumptions (A1)–(A3) and is established at one loop about the round <span><math><msup><mrow><mi>S</mi></mrow><mrow><mi>D</mi></mrow></msup></math></span> saddle in the probe regime <span><math><mrow><mi>G</mi><msub><mrow><mi>E</mi></mrow><mrow><mi>clock</mi></mrow></msub><mo>/</mo><mi>R</mi><mo>≪</mo><mn>1</mn></mrow></math></span>; a self-consistent backreacting or higher-loop extension is a natural next step. In earlier work (Ali and Ali 2025; Ali 2025) we argued that unbroken SU(3) confinement at <span><math><mrow><mi>T</mi><mo>→</mo><mn>0</mn></mrow></math></span> can account for the observed value of the cosmological constant and for the origin of the fundamental constants <span><math><mrow><mo>(</mo><mo>ħ</mo><mo>,</mo><mi>G</mi><mo>,</mo><mi>c</mi><mo>)</mo></mrow></math></span> as effective couplings fixed by the SU(3) vacuum structure; this makes SU(3) the natural candidate for the internal clock of de Sitter, whose radius and temperature are themselves set by the same cosmological constant. Here that idea is implemented with three explicit SU(3) realizations (qutrit, Cartan weight-lattice, and <span><math><mrow><mi>U</mi><msup><mrow><mrow><mo>(</mo><mn>1</mn><mo>)</mo></mrow></mrow><mrow><mn>2</mn></mrow></msup></mrow></math></span> rotor), for which the observer-inclusive density of states factorizes into a universal gravity factor, a universal worldline residue, and a clock-dependent SU(3) weight.</div><div><strong>Summary of con","PeriodicalId":8249,"journal":{"name":"Annals of Physics","volume":"487 ","pages":"Article 170364"},"PeriodicalIF":3.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146075999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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