We apply the localization method to the BFSS matrix model with a particular class of boundary conditions, that is related to a scattering problem of 11-dimensional M-theory. For the boundary condition that corresponds to the three-point amplitude of gravitons, we exactly compute the partition function of the model based on the localization method. We find that the result correctly reproduces the expected momentum dependence of the three point amplitude.

Japan

Yuhma Asano

Goro Ishiki

Yoshua Murayama

Localization of the BFSS matrix model and three-point amplitude in M-theory

<p>The flux of Hidden Sector particles from the Galactic halo reaching an underground detector can be significantly attenuated by interactions within the Earth for sufficiently large scattering cross- sections. This attenuation gives rise to a characteristic daily modulation in the detection rate, due to Earth’s rotation. We present results from a search for such a modulation using a 1.257 kg-day dataset collected with the DAMIC-M Low Background Chamber. A model-independent analysis reveals no significant modulation in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mn>1</mn><msup><mrow><mi>e</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math> event rate over periods from 1 to 48 h, highlighting the excellent temporal stability of the detector. In a complementary model-dependent analysis, we target the expected daily modulation signature of Hidden Sector particles, with masses in the range <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mo stretchy="false">[</mo><mn>0.53</mn><mo>,</mo><mi>2</mi><mo stretchy="false">]</mo><mtext> </mtext><mtext> </mtext><mrow><mi>MeV</mi><mo>/</mo></mrow><msup><mi mathvariant="normal">c</mi><mn>2</mn></msup></math>, interacting with electrons via a dark photon mediator. By leveraging the expected temporal evolution of the signal, we set improved constraints on Dark Matter masses below <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mn>1.2</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi><mo>/</mo><msup><mi mathvariant="normal">c</mi><mn>2</mn></msup></math>, surpassing our previous limits.</p>

United States

K. Aggarwal

I. Arnquist

France

N. Avalos

X. Bertou

Spain

N. Castelló-Mor

C. Centeno-Lorca

A.E. Chavarria

J. Cuevas-Zepeda

A. Dastgheibi-Fard

C. De Dominicis

O. Deligny

J. Duarte-Campderros

Argentina

E. Estrada

R. Gaïor

Switzerland

E.L. Gkougkousis

T. Hossbach

L. Iddir

B.J. Kavanagh

B. Kilminster

Canada

I. Lawson

A. Letessier-Selvon

H. Lin

P. Loaiza

A. Lopez-Virto

R. Lou

H. Lumengo-Kidimbu

K.J. McGuire

S. Munagavalasa

J. Noonan

D. Norcini

S. Paul

P. Privitera

P. Robmann

B. Roach

D. Rosenmerkel

M. Settimo

R. Smida

M. Traina

R. Vilar

R. Yajur

D. Venegas-Vargas

C. Zhu

Y. Zhu

Daily modulation constraints on light dark matter with DAMIC-M

<p>Nucleon-nucleon systems in the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><msub><mrow><mi>S</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow><mprescripts></mprescripts><none></none><mrow><mn>3</mn></mrow></mmultiscripts></mrow></math> and the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><msub><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow><mprescripts></mprescripts><none></none><mrow><mn>1</mn></mrow></mmultiscripts></mrow></math> channels are studied in lattice quantum chromodynamics at a pion mass of approximately <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>π</mi></msub><mo>≈</mo><mn>292</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>, employing three <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>N</mi><mi>f</mi></msub><mo>=</mo><mn>2</mn><mo>+</mo><mn>1</mn></math> ensembles with the same pion mass and lattice spacing <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mi>a</mi><mo>=</mo><mn>0.10530</mn><mo stretchy="false">(</mo><mn>18</mn><mo stretchy="false">)</mo><mtext> </mtext><mtext> </mtext><mi>fm</mi></math> but different spatial volumes. Finite-volume energies of the nucleon-nucleon systems are determined in both the rest frame and a moving frame. The distillation quark smearing method is applied to improve the precision and to ensure the symmetric correlators by using the same interpolating operators at sink and source. The scattering amplitudes are extracted from the finite-volume spectra using the Lüscher’s finite-volume method. At the studied pion mass, both the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><msub><mrow><mi>S</mi></mrow><mrow><mn>1</mn></mrow></msub></mrow><mprescripts></mprescripts><none></none><mrow><mn>3</mn></mrow></mmultiscripts></mrow></math> (deuteron) and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><mmultiscripts><mrow><msub><mrow><mi>S</mi></mrow><mrow><mn>0</mn></mrow></msub></mrow><mprescripts></mprescripts><none></none><mrow><mn>1</mn></mrow></mmultiscripts></mrow></math> (dineutron) channels exhibit a virtual state pole, with binding energies of <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mn>6</mn><mrow><mo>−</mo><mn>3</mn></mrow><mrow><mo>+</mo><mn>5</mn></mrow></msubsup><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math> and <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msubsup><mn>11</mn><mrow><mo>−</mo><mn>5</mn></mrow><mrow><mo>+</mo><mn>6</mn></mrow></msubsup><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math>, respectively. To investigate the effects of the left-hand cut, an alternative method—the nonperturbative Hamiltonian framework—is used for the scattering analysis and yields consistent results with those from the Lüscher method.</p>

China

Kuan Zhang

Kang Yu

Yiqi Geng

Chuan Liu

Liuming Liu

Peng Sun

Jia-Jun Wu

Ruilin Zhu

Two-nucleon systems at <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><msub><mi>m</mi><mi>π</mi></msub><mo>≈</mo><mn>292</mn><mtext> </mtext><mtext> </mtext><mi>MeV</mi></math> from lattice QCD

In this article, we investigate the observational properties of the Reissner–Nordstr $$\ddot{\textrm{o}}$$ m–Tangherlini (RNT) black hole (BH). Firstly, we briefly explore the spacetime properties of the RNT BH, including the horizon structure and scalar invariants. It was found that the values of the event horizon radius decrease with increasing BH dimension and charge. Subsequently, we explore the massive and massless particle dynamics around RNT BH. Afterwards, gravitational weak lensing is investigated for two plasma types: uniform and non-uniform. Our results show that a uniform plasma increases the deflection angle of light around an RNT BH, whereas a non-uniform plasma decreases it. Finally, we study the BH shadow and constrain the values of the spacetime parameters using the Event Horizon Telescope (EHT) observational results.

Weiqiang Yang

Uzbekistan

Mirzabek Alloqulov

Akbar Davlataliev

Ahmadjon Abdujabbarov

Bobomurat Ahmedov

Chengxun Yuan

Chen Zhou

Observational signature of Reissner–Nordstr $$\ddot{\textrm{o}}$$ m–Tangherlini black hole

A correction to this paper has been published: https://doi.org/10.1007/JHEP01(2026)099

Bruno Bento

Miguel Montero

Erratum to: An M-theory dS maximum from Casimir energies on Riemann-flat manifolds

We study the partition function associated with the democratic formulation of M-theory, focusing on its global definition and quantum properties. Using a path integral representation that makes manifest the underlying cohomological structure, we analyze the coupled system of M-theory form fields ($\textit{A}$ + $\textit{A}$ ), and the background fields ($\textit{C}$ + $\textit{C}$ ), as well as their associated global transformations. We show that the resulting description is naturally captured by a Heisenberg-type group reflecting the presence of a quadratic coupling between electric and magnetic degrees of freedom. This framework provides a transparent characterization of the global structure of the theory, clarifies the role of higher-form global symmetry, and allows for a consistent definition of the partition function in terms of higher-dimensional auxiliary manifolds.

South Korea

J. Rosabal

Holographic partition function of democratic M-theory

We study the equation of state (EoS) of QCD matter in a bottom-up holographic setup that combines an Einstein-Maxwell-dilaton (EMD) sector with an improved Karch-Katz-Son-Stephanov (KKSS) flavor action. In the probe approximation, we perform an inverse reconstruction of the model functions by parameterizing them with neural networks and solving the EMD equations via a differentiable ODE solver (a neural ODE framework), calibrating the model to a reference thermodynamic table for $(2+1)$ -flavor QCD at finite temperature and finite baryon chemical potential. The reconstructed model functions are then parameterized and kept fixed across thermodynamic states. Next, viewing the EMD sector as an effective description of pure Yang-Mills theory, we fix its parameters by fitting the $\mu_B=0$ lattice pure-glue EoS using a hybrid optimization strategy. Finally, we go beyond the probe limit and solve the coupled EMD+KKSS equations with back-reaction, using the pure-glue-calibrated EMD sector as a fixed input and varying the KKSS couplings to compare with the $\mu_B=0$ two-flavor lattice EoS. We find a visible mismatch and a high-temperature behavior in which the back-reacted dimensionless ratios approach a nearly $\beta_1$ -insensitive plateau close to the pure-glue baseline, providing a simple structural diagnostic for the present flavor-sector truncation.

Yutian Deng

Mei Huang

Lin Zhang

Holographic QCD equation of state constrained by lattice QCD: neural-ODE for probe-limit and a back-reaction test * Start-up funding from Sun Yat-sen University (SYSU) (Y. Deng and L. Zhang); National Natural Science Foundation of China (NSFC) (12235016) (L. Zhang and M. Huang) and 12221005 (M. Huang)

AdS × S × S solutions warped over a Riemann surface, Σ, are indexed by a parameter, $\textit{γ}$, that defines the superconformal algebra, $\textit{D}$(2, 1; $\textit{γ}$) ⨁ $\textit{D}$(2, 1; $\textit{γ}$) they preserve. We show that these solutions come from multiple back-reacted M2-M5 spikes, and that different values of $\textit{γ}$ correspond to different scaling limits of the same M2-M5 solutions. We find that when $\textit{γ}$ switches from positive to negative, the infrared region of the AdS switches from the tip of spikes, far from the M5 branes, to the bottom of the spikes, far from the M2 branes. We also explain how the bubbling negative-$\textit{γ}$ solutions emerge from the geometric transition of multiple M2-M5 spikes.

Iosif Bena

Israel

Raphaël Dulac

Dimitrios Toulikas

Nicholas Warner

Effervescent spikes in M-theory

We present constraints on the sum of neutrino masses ∑ <italic>m<inf>&#957;</inf></italic> from a dataset incorporating the full SPT-3G 2018 TT/TE/EE+lensing spectra together with Planck PR4 lensing and low-&#8467; parts of the Planck PR3 spectra. Using it together with the DESI DR2 BAO measurements, we arrive at a 95% upper limit of &#8721; <italic>m<inf>&#957;</inf></italic>&#8239;&lt;&#8239;0.11&#8201;eV, relaxing the tension between &#923;CDM and lower bounds on &#8721; <italic>m<inf>&#957;</inf></italic> based on neutrino oscillation experiments as compared to the <monospace>Planck+DESI</monospace> constraint. When including DES Y1 weak lensing information and the Pantheon+ SNIa catalog, the limit is further loosened to &#8721; <italic>m<inf>&#957;</inf></italic>&#8239;&lt;&#8239;0.138&#8201;eV with a slight preference for &#8721; <italic>m<inf>&#957;</inf></italic>&#8239;&gt;&#8239;0. By contrast, replacing SPT-3G 2018 primary CMB and lensing spectra with ones from the SPT-3G 2019-2020 (D1) release tightens the overall constraint to &#8239;&lt;&#8239;0.082&#8201;eV and pushes the &#8721; <italic>m<inf>&#957;</inf></italic> posterior mode value to zero, indicating a preference for quasi-negative neutrino masses in line with the D1 analysis. This is a curious shift within SPT-3G measurements of the same field taken in 2018 and in 2019-2020 and processed with different analysis pipelines.

Russia

Dmitry Gorbunov

Nikita Nedelko

Changing constraints on ∑ <italic>m<inf>&#957;</inf></italic> from SPT-3G 2018 to D1 in the context of DESI DR2

In this work, Static wormhole models are examined within the framework of curvature-based <math altimg='si17.svg'><mrow><mi mathvariant='italic'>f</mi><mo>(</mo><mi mathvariant='fraktur'>R</mi><mo>,</mo><msub><mi mathvariant='fraktur'>L</mi><mi mathvariant='fraktur'>m</mi></msub><mo>,</mo><mi mathvariant='italic'>T</mi><mo>)</mo></mrow></math> gravity theory. A relationship between the matter energy density and pressure is proposed for the Morris-Thorne wormhole geometry with a constant redshift function. By incorporating a gradient-dependent equation of state ( <math altimg='si18.svg'><mrow><msub><mi>P</mi><mi>r</mi></msub><mo linebreak='goodbreak'>=</mo><msub><mi>P</mi><mi>r</mi></msub><mrow><mo>(</mo><mi>&#961;</mi><mo>,</mo><msup><mi>&#961;</mi><mo>&#8242;</mo></msup><mo>)</mo></mrow></mrow></math> and <math altimg='si19.svg'><mrow><msub><mi>P</mi><mi>t</mi></msub><mo linebreak='goodbreak'>=</mo><msub><mi>P</mi><mi>t</mi></msub><mrow><mo>(</mo><msub><mi>P</mi><mi>r</mi></msub><mo>,</mo><msubsup><mi>P</mi><mi>r</mi><mo>&#8242;</mo></msubsup><mo>)</mo></mrow></mrow></math>), we derive exact wormhole solutions for two representative cases. Our analysis shows that exact wormhole models can admit null energy condition violations localized at the throat, while preserving a non-negative matter energy density. The stability analysis is performed via the Tolman&#8211;Oppenheimer-Volkoff equation under hydrostatic equilibrium, demonstrating that the balance among anisotropic and hydrostatic forces sustains the wormhole&#8217;s stable configuration. For positive and negative values of <italic>&#950;</italic>, the energy flux attains a pronounced negative magnitude, inducing an outward flux that supports the stability of the wormhole throat. The geometric characteristics of the wormhole are examined through embedding diagrams, and the total exotic matter required to maintain the configuration is evaluated using the volume integral quantifier. Simultaneously, the effective potential demonstrates enhanced photon confinement and increased stability of particle orbits.

India

Sweeti Kiroriwal

Azerbaijan

Oman

S.K. Maurya

Jitendra Kumar

Wormholes generated by a density-gradient dependent equation of state in <math altimg='si17.svg'><mrow><mi mathvariant='italic'>f</mi><mo>(</mo><mi mathvariant='fraktur'>R</mi><mo>,</mo><msub><mi mathvariant='fraktur'>L</mi><mi mathvariant='fraktur'>m</mi></msub><mo>,</mo><mi mathvariant='italic'>T</mi><mo>)</mo></mrow></math> gravity