In the context of the left-right symmetric model, we study the interplay of neutrinoless double beta (0 <italic>&#957;&#946;&#946;</italic>) decay, parity-violating M&#248;ller scattering, and high-energy colliders, resulting from the Yukawa interaction of the right-handed doubly-charged scalar to electrons, which could evade the severe constraints from charged lepton flavor violation. The 0 <italic>&#957;&#946;&#946;</italic> decay amplitude receives additional contributions from right-handed sterile neutrinos. The half-life, calculated in the effective field theory framework, allows for an improved description of the contributions involving non-zero mixing between left- and right-handed <italic>W</italic> bosons and those arising from exchanging a light right-handed neutrino. We find that the relative sensitivities between the low-energy (or high-precision) and high-energy experiments are affected by the left-right mixing. On the other hand, our results show how the interplay of collider and low-energy searches provides a manner to explore regions that are inaccessible to 0 <italic>&#957;&#946;&#946;</italic> decay experiments.

China

Gang Li

United States

Michael J. Ramsey-Musolf

Sebastián Urrutia Quiroga

Italy

Juan Carlos Vasquez

Dissecting lepton number violating interactions in the left-right symmetric model: 0 <italic>&#957;&#946;&#946;</italic> decay, M&#248;ller scattering, and collider searches

This study rigorously examines the influence of dark matter within the framework of <math altimg='si10.svg'><mrow><mi>f</mi><mo>(</mo><mi mathvariant='script'>R</mi><mo>,</mo><msub><mi mathvariant='script'>L</mi><mi>m</mi></msub><mo>)</mo></mrow></math> gravity, with a particular emphasis on its critical role in facilitating traversable wormhole solutions. By employing anisotropic matter sources modeled through Bose-Einstein condensates and Einasto density profiles, we derive a novel class of wormhole solutions. The construction of the shape function relies on the density profile equation in conjunction with modified field equations, thereby establishing a theoretical foundation for these solutions. Careful selection of parameters ensures that the proposed solutions satisfy all requisite conditions for traversability. Moreover, we conduct a systematic evaluation of energy conditions across two distinct scenarios, further validating the physical viability of the models. The investigation also extends to analyzing anisotropic effects, exoticity parameters, and active gravitational mass. This work presents a comprehensive exploration of the physical feasibility and stability of wormhole structures within the context of <math altimg='si10.svg'><mrow><mi>f</mi><mo>(</mo><mi mathvariant='script'>R</mi><mo>,</mo><msub><mi mathvariant='script'>L</mi><mi>m</mi></msub><mo>)</mo></mrow></math> modified gravity theories, offering significant contributions to our understanding of the interplay between dark matter and advanced gravitational phenomena.

India

H Aruna Kumara

Chaitra Chooda Chalavadi

V. Venkatesha

Investigating wormhole structures in <math altimg='si10.svg'><mrow><mi>f</mi><mo>(</mo><mi mathvariant='script'>R</mi><mo>,</mo><msub><mi mathvariant='script'>L</mi><mi>m</mi></msub><mo>)</mo></mrow></math> gravity: Implications for dark matter

We present, to our knowledge, the first systematic study of early-late cosmic evolution and acceleration in the framework of <math altimg='si15.svg'><mrow><mi>f</mi><mo>(</mo><mi>T</mi><mo>,</mo><msub><mi mathvariant='script'>L</mi><mi>m</mi></msub><mo>)</mo></mrow></math> gravity, an extension of teleparallel theories coupling torsion with the matter Lagrangian. By incorporating the Big-Bang Nucleosynthesis (BBN) bound on the freeze-out temperature, we obtain a tight constraint on the inverse-torsion parameter, ensuring consistency with early-time physics. Employing Markov Chain Monte Carlo analyses with progressively richer observational datasets, CC, Union3, and SN22 supernovae, we constrain a well-motivated model and reconstruct key cosmological functions. The reconstructed Hubble and distance modulus functions show excellent agreement with the observations, confirming the observational viability of the model. The model successfully reproduces the observed late-time expansion history, yielding a transition from deceleration to acceleration through the deceleration parameter. The effective equation of state is found to remain negative throughout, with present values <math altimg='si16.svg'><mrow><msub><mi>w</mi><mn>0</mn></msub><mo linebreak='goodbreak'>&gt;</mo><mo>&#8722;</mo><mn>1</mn></mrow></math>, indicating a quintessence-like behavior rather than a cosmological constant or phantom regime. These results highlight the ability of <math altimg='si15.svg'><mrow><mi>f</mi><mo>(</mo><mi>T</mi><mo>,</mo><msub><mi mathvariant='script'>L</mi><mi>m</mi></msub><mo>)</mo></mrow></math> gravity to mimic the concordance scenario while allowing controlled deviations in the expansion history.

Sai Swagat Mishra

Suchita Patel

P.K. Sahoo

BBN to late-time acceleration in <math altimg='si15.svg'><mrow><mi>f</mi><mo>(</mo><mi>T</mi><mo>,</mo><msub><mi mathvariant='script'>L</mi><mi>m</mi></msub><mo>)</mo></mrow></math> gravity

The dimensional reduction of M-theory couplings at order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mo>ℓ</mo><mi>p</mi><mn>6</mn></msubsup></math> is known to produce one-loop <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mrow><mi>α</mi></mrow><mrow><mo>′</mo><mn>3</mn></mrow></msup></math> corrections in type IIA string theory. In this paper, we perform the Kaluza-Klein reduction of the M-theory Chern-Simons coupling <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>t</mi><mn>8</mn></msub><msub><mi>ε</mi><mn>11</mn></msub><mi>A</mi><msup><mi>R</mi><mn>4</mn></msup></math> at this order. By meticulously accounting for nongauge-invariant total derivative terms, we derive the complete set of corresponding one-loop, gauge-invariant couplings in the type IIA effective action. Our results not only reproduce the standard Chern-Simons term <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>t</mi><mn>8</mn></msub><msub><mi>ε</mi><mn>10</mn></msub><mi>B</mi><msup><mi>R</mi><mn>4</mn></msup></math>—which is gauge invariant up to total derivatives—but also unveil a new set of gauge-invariant couplings involving Ramond-Ramond and Neveu-Schwarz–Neveu-Schwarz field strengths. To validate our findings, we test their consistency under string dualities. We dimensionally reduce the derived type IIA couplings on a K3 manifold and show that the resulting one-loop <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>α</mi><mo>′</mo></msup></math> corrections in six dimensions transform under S-duality into the dimensional reduction of the tree-level heterotic string Chern-Simons coupling <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>H</mi><mrow><mi>μ</mi><mi>ν</mi><mi>α</mi></mrow></msub><msup><mi mathvariant="normal">Ω</mi><mrow><mi>μ</mi><mi>ν</mi><mi>α</mi></mrow></msup></math> on <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msup><mi>T</mi><mn>4</mn></msup></math>. This nontrivial agreement provides strong evidence for the correctness of both the M-theory Chern-Simons term and its reduction to type IIA.

Iran

Mohammad R. Garousi

Dimensional reduction of the M-theory Chern-Simons term at order <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mo>ℓ</mo><mi>p</mi><mn>6</mn></msubsup></math>

We discuss that the string/M-theory partition function requires a choice of ensembles, depending on which background fields are held fixed. The background fields correspond to worldvolume couplings in the effective action approach to the superstring, which we extrapolate to the M2-brane. One natural ensemble in this context, which we call the M2-ensemble, corresponds to fixing the value of the M-theory three-form potential. In holographic setups the choice of ensemble is important when comparing to observables in the dual field theory. Indeed, in AdS holography the M2-ensemble does not map gravitational observables directly to field theory observables at a fixed rank $\textit{N}$, but rather to observables in the grand canonical ensemble. We remark that many M2-brane partition functions take a simple form in this ensemble hinting at one-loop exactness. We also discuss how in AdS holography, the M2-ensemble does correspond to the canonical ensemble in the field theory, i.e. the (2,0) theory at fixed rank $\textit{N}$.

United Kingdom

Friðrik Gautason

Jesse Muiden

Ensembles in M-theory and holography

Within the framework of the next-to-minimal supersymmetric (SUSY) extension of the Standard Model (SM) with a local B-L gauge symmetry (N-B-LSSM), we study lepton flavor violating (LFV) $ \tau\rightarrow e M^+ M^- $ decays: $ \tau \rightarrow e \pi^+\pi^- $ , $ \tau \rightarrow e \pi^+K^- $ , and $ \tau \rightarrow e K^+K^- $ . Based on the latest experimental data, the influence of different sensitive parameters on the branching ratios is considered. It can be seen from the numerical analysis that the main sensitive parameters and LFV sources are non-diagonal elements corresponding to the initial and final leptons. This work can provide a basis for discovering the existence of new physics (NP).

Rong-Zhi Sun

Shu-Min Zhao

Shuang Di

Portugal

Xing-Xing Dong

Study of ${\boldsymbol\tau\rightarrow {\boldsymbol e M^+ M^-}}$ decays in N-B-LSSM * Supported by National Natural Science Foundation of China (NNSFC) (12075074), Natural Science Foundation of Hebei Province (A2023201040, A2022201022, A2022201017, A2023201041), Natural Science Foundation of Hebei Education Department (QN2022173), Post-graduate's Innovation Fund Project of Hebei University (HBU2024SS042), the Project of the China Scholarship Council (CSC) (202408130113). X. Dong acknowledges support from Fundação para a Ciência e a Tecnologia (FCT, Portugal) through the projects CFTP FCT Unit (UIDB/00777/2020, UIDP/00777/2020)

We present the first calculation of the high-energy corrections to the process of isolated photon production in association with two jets. These corrections both stabilise the perturbative behaviour in $$ {m}_{j_1{j}_2} $$ and lead to a significantly improved description of data from a recent ATLAS measurement.

Switzerland

Jeppe Andersen

Spain

Andreas Maier

Malina Rosca

Germany

Giacomo Ruisi

Stable perturbative predictions for isolated photon production with a jet pair at large $$ {m}_{j_1{j}_2} $$

We present the perturbative results of the discretization errors proportional to the quark mass [<math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mi>a</mi><mi>m</mi><mo stretchy="false">)</mo></math>] on the QCD running coupling within lattice perturbation theory. Our analysis involves calculating the two-loop renormalization factor <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>Z</mi><mi>g</mi></msub></math> using improved lattice actions for the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>S</mi><mi>U</mi><mo stretchy="false">(</mo><msub><mi>N</mi><mi>c</mi></msub><mo stretchy="false">)</mo></math> gauge group and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>f</mi></msub></math> multiplets of fermions with a finite quark mass. We employ the background field method to compute <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>Z</mi><mi>g</mi></msub></math>, by calculating quantum corrections on both the background and quantum gluon propagator, respecting the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mi>a</mi><mo stretchy="false">)</mo></math> improvement. This allows us to evaluate the perturbative <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mi>a</mi><mi>m</mi><mo stretchy="false">)</mo></math> lattice errors which affect the determination of the running coupling. Eliminating these <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mi>a</mi><mi>m</mi><mo stretchy="false">)</mo></math> effects is crucial for the nonperturbative studies of precision determinations of the strong coupling constant using lattice field theory.

Cyprus

M. Costa

D. Gavriel

H. Panagopoulos

G. Spanoudes

Perturbative determination of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi mathvariant="script">O</mi><mo stretchy="false">(</mo><mi>a</mi><mi>m</mi><mo stretchy="false">)</mo></math> improvement on the QCD running coupling

To give more credence to the M-theoretic Emergence Proposal it is important to show that also classical kinetic terms in a low energy effective action arise as a quantum effect from integrating out light towers of states. We show that for compactifications of type IIA on Calabi-Yau manifolds, the classical weak coupling Yukawa couplings, which are the triple intersection numbers of the Calabi-Yau threefold, can be obtained from the 1/2-BPS protected one-loop Schwinger integral over $\textit{D}$2-$\textit{D}$0 bound states, after employing a novel regularization for the final infinite sum of Gopakumar-Vafa invariants. Approaching the problem in a consecutive manner from 6D decompactification over emergent string to the ultimate M-theory limits, we arrive at a mathematically concrete regularization that involves finite distance degeneration limits of Calabi-Yau threefolds in an intriguing way. We test and challenge this proposal by the concrete determination of the periods around such degeneration points for threefolds with one Kähler modulus and the two examples $\textit{ℙ}$ [18] and $\textit{ℙ}$ [12].

Ralph Blumenhagen

Aleksandar Gligovic

Emergence of CY triple intersection numbers in M-theory

Axionlike particles (ALPs), hypothetical particles beyond the Standard Model (SM), are considered as promising dark matter candidates. ALPs can convert into photons and vice versa in a magnetic field via the Primakoff effect, potentially generating detectable oscillation in <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>γ</mi></math>-ray spectra. This study analyzes 16.5 years of data from the Fermi Large Area Telescope (Fermi-LAT) on NGC 1275, the brightest galaxy in the Perseus cluster, to constrain the ALP parameter space. Our results improve the previous 95% exclusion limits of the photon-ALP coupling <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>g</mi><mrow><mi>a</mi><mi>γ</mi></mrow></msub></math> by a factor of 2 in the ALP mass range of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>4</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>10</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi><mo>≲</mo><msub><mi>m</mi><mi>a</mi></msub><mo>≲</mo><mn>5</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>9</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></math>. Moreover, we investigate the projected sensitivity of the future Very Large Area <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>γ</mi></math>-ray Space Telescope (VLAST) on searching for ALPs. We find that (i) the expected sensitivity on the photon-ALP coupling <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>g</mi><mrow><mi>a</mi><mi>γ</mi></mrow></msub></math> can be stronger than that from the upcoming International Axion Observatory in the ALP mass range of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>2</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>11</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi><mo>≲</mo><msub><mi>m</mi><mi>a</mi></msub><mo>≲</mo><mn>1</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>7</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></math>, with the best sensitivity of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>g</mi><mrow><mi>a</mi><mi>γ</mi></mrow></msub><mo>∼</mo><mn>7</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>13</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>GeV</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>a</mi></msub><mo>∼</mo><mn>2</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>10</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></math>; (ii) VLAST can extend the sensitivity of the ALP masses below <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>5</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>12</mn></mrow></msup><mtext> </mtext><mtext> </mtext><mi>eV</mi></math>, where the photon-ALP coupling <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>g</mi><mrow><mi>a</mi><mi>γ</mi></mrow></msub><mo>≳</mo><mn>1.5</mn><mo>×</mo><msup><mn>10</mn><mrow><mo>−</mo><mn>11</mn></mrow></msup><mtext> </mtext><mtext> </mtext><msup><mrow><mi>GeV</mi></mrow><mrow><mo>−</mo><mn>1</mn></mrow></msup></math> will be excluded; (iii) the entire parameter space of ALP accounting for TeV transparency can be fully tested. These results demonstrate that VLAST will offer an excellent opportunity for ALPs searches.

Zhi-Qi Guo

Yue-Lin Sming Tsai

Lei Wu

Zi-Qing Xia

Constraints on axionlike particles from 16.5 years of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>F</mi><mi>e</mi><mi>r</mi><mi>m</mi><mi>i</mi></math>-LAT data and prospects for VLAST