Texture-zero ansatze offer an economical description of neutrino masses, with current data allowing only seven inequivalent two-zero Majorana textures in the charged-lepton mass basis. We investigate how such textures can arise from non-invertible symmetries realized through $\textit{ℤ}$ gauging of $\textit{ℤ}$ . In contrast to $\textit{ℤ}$ gauging, which necessarily induces diagonal neutrino mass terms via the Weinberg operator, $\textit{ℤ}$ gauging admits complex representations and allows a richer class of neutrino mass textures. If the light neutrino mass is described by the Weinberg operator, we find that the textures , , and can be realized from the $\textit{ℤ}$ gauging of $\textit{ℤ}$ symmetry, while all the seven phenomenologically viable two-zero textures can emerge from $\textit{ℤ}$ gauging of $\textit{ℤ}$ symmetry without requiring supersymmetry. When the neutrino mass is generated by the type-I seesaw mechanism, the structure of the non-invertible symmetry is more restrictive, yielding only texture for $\textit{N}$ ≠ 7. These results demonstrate the strong predictive power of non-invertible symmetries for neutrino mass textures. Furthermore, the more general $\textit{ℤ}$ gauging of the $\textit{ℤ}$ symmetry with $\textit{n}$ > 3 is analyzed, which results in novel fusion rules.

China

Bu-Yao Qu

Zheng Jiang

Gui-Jun Ding

Two-zero textures of the Majorana neutrino mass matrix from $\textit{ℤ}$ 3 gauging of $\textit{ℤ}$ $\textit{N}$ non-invertible symmetry

We study self-dual instantons of topological charge $$ Q=\frac{r}{N} $$ , ∀$\textit{r}$ ∈ $\textit{ℕ}$, in $\textit{SU}$ ($\textit{N}$) Yang-Mills theory on $$ {\mathbbm{T}}^4 $$ with ’t Hooft twists, by embedding them into worldvolume theories of $\textit{D}$-branes. To study their moduli, we construct the wrapped intersecting brane configurations dual to general constant field strength instanton backgrounds. We show that, locally, the moduli space is identified with the Higgs branch of an $$ \mathcal{N} $$ =2 supersymmetric theory. This parameterization of the moduli space is equivalent to one recently found in field theory, but is obtained with significantly less effort and has manifest hyper-Kähler structure. Our hope is that combining different perspectives on instantons on the twisted torus will help understand the still unknown global structure of the moduli space for general solutions with $$ Q=\frac{r}{N} $$ as well as the nature of instantons with all moduli turned on — when some $\textit{Q}$<1 and all $\textit{Q}$≥1 instantons become space-time dependent. For integer $\textit{Q}$, these are expected to match the ADHM solution in an appropriately taken infinite volume limit.

Canada

Erich Poppitz

$\textit{D}$-branes and fractional instantons on a twisted $$ {\mathbbm{T}}^4 $$ : the moduli space as an $$ \mathcal{N} $$ = 2 supersymmetric Higgs branch

The complete classification of the landscape of 6D $$ \mathcal{N} $$ = (1) string vacua remains an open problem. In this work we prove a classification theorem for 6D $$ \mathcal{N} $$ = (1) asymmetric orbifolds utilizing a correspondence with orbifolds of chiral 2D SCFTs with $\textit{c}$ = 24 (or $\textit{c}$ = 12). Interestingly, this class of theories can give rise to 6D vacua in which the only massless degrees of freedom reside in the gravity multiplet, with no moduli other than the dilaton — thus corresponding to truly isolated vacua, called $\textit{string islands}$. It is expected that there exist five new type II islands with as-yet-unknown constructions. In this work we construct them all using asymmetric $\textit{ℤ}$ -orbifolds of Type II on $\textit{T}$ with $\textit{n}$ = 5, 8, 10, 12. We show that the cases $\textit{n}$ = 5, 8 admit non-trivial discrete theta angles which have important consequences for both the string and particle charge lattices. In fact they provide examples of BPS-incompleteness and the strongest failure of the lattice weak gravity conjecture. Our work is expected to finalize our understanding of all perturbative 6D $$ \mathcal{N} $$ = (1) theories.

United States

Zihni Baykara

Héctor Freitas

Houri-Christina Tarazi

String islands, discrete theta angles and the 6D $$ \mathcal{N} $$ = (1) string landscape

By breaking dual conformal invariance, we transform cluster-algebraic predictions for the alphabet of 9-point amplitudes in $$ \mathcal{N} $$ = 4 super Yang-Mills theory to analogous predictions for 5- and 6-point processes in QCD. We start by obtaining, for the first time, candidate letters for 6-point processes with one massive external leg, and discover that they surprisingly also contain nested square roots. We confirm that our results essentially contain the alphabet of all 1-loop integrals with these kinematics, and in their massless limit also the recently computed alphabet of finite, planar 2-loop amplitudes for 6-point massless QCD processes. In the latter case, we additionally find 162 letters that may appear at higher loops. We similarly produce candidate letters for 5-point 2-mass processes, whose comparison with the literature reveals a nontrivial overlap that also includes new letters.

Germany

Rigers Aliaj

Gabriele Dian

United Kingdom

Greece

Georgios Papathanasiou

Novel cluster-algebraic letters for 5- and 6-point QCD processes

Hadronic tensors encode the nonperturbative structure of hadrons probed in deep inelastic scattering (DIS), yet their direct evaluation requires real-time evolution that presents a challenge for traditional Euclidean lattice approaches. In this work, we present the first quantum simulation of real-time hadronic current-current correlators in a confining gauge theory, from which DIS-inspired structure functions are extracted as a proof-of-principle demonstration in the Schwinger model, i.e (1+1)-dimensional QED. Using two complementary quantum-simulation strategies — quantum-circuit and tensor-network methods — we compute the real-time current-current correlator directly on the lattice and validate our results against exact diagonalization where applicable. From this correlator, we compute the hadronic tensor and determine the longitudinal structure function, the sole nonvanishing DIS observable in two space-time dimensions. Our study demonstrates that quantum simulation offers a viable complementary pathway towards the evaluation of real-time observables relevant for hadronic structure. It also provides a foundation for extending the calculations from Schwinger model to other gauge theories.

Kazuki Ikeda

Zhong-Bo Kang

Dmitri Kharzeev

Spain

Wenyang Qian

Quantum simulation of real-time current correlators and DIS-inspired observables in the Schwinger model

It has been suggested that Hořava-Witten theory could provide a concrete realization of the Dark Dimension Scenario. In this context, the observable Standard Model sector is naturally localized in the micron-sized large dimension, which is the interval in the eleventh direction. Considering Calabi-Yau manifolds supporting generic vector bundles including also abelian factors, we point out that symmetric tadpole cancellation on the $\textit{E}$ walls has the potential to ameliorate some of the issues of such a realization, including too fast proton decay. By taking not only the hierarchically small value of the dark energy but also the size of the Standard Model gauge couplings into account, one is driven to a special infinite distance limit, which is the Hořava-Witten analogue of a limit recently at the focus of the M-theoretic Emergence Proposal. Extrapolating results obtained for BPS-saturated amplitudes, we speculate about the possibility of obtaining the moduli dependence of the scalar potential, the gauge couplings and the Planck scale by simple one-loop Schwinger integrals over towers of states.

Ralph Blumenhagen

Antonia Paraskevopoulou

Towards the realization of the dark dimension scenario in Hořava-Witten theory

We study detector operators measuring energy to a power ∆ – 2 at null infinity in four-dimensional gauge theories and gravity. These operators transform as conformal primaries on the celestial sphere and provide a natural basis for describing energy-flux observables in scattering processes. Using the collinear factorization of scattering amplitudes, we derive the universal leading structure of the operator product expansion. A key consequence of our analysis is the precise identification of the ∆ = 2 detector with the particle-number operator. Exploiting the fact that soft charges generate symmetries of the $\textit{S}$-matrix, we show that the residue of the number operator, evaluated on scattering states, can be represented in terms of bilinears of conformally soft currents: in gravity, the operator is the square of the supertranslation generator, while in Yang-Mills it yields a product of $\textit{SU}$ ($\textit{N}$) Kac-Moody soft currents. This work thus establishes a direct link between detector observables and the soft sector of celestial holography.

Chile

Hernán González

Belgium

Jakob Salzer

Energy detectors and asymptotic symmetries

We propose a novel mechanism for the cosmological production of keV–GeV mass dark matter that interacts with the Standard Model through a small effective magnetic dipole moment. Such an interaction can be radiatively generated if dark matter couples to heavier charged particles. Previous studies have focused on the case where these charged states are much heavier than the reheat temperature, such that freeze-in production of dark matter is sensitive to the ultraviolet details of reheating. Here, we instead consider the possibility that these heavy states have masses comparable to the dark matter mass and are charged under a new kinetically-mixed $\textit{U}$ (1) . As a result, dark matter production is dominated by the infrared freeze-in of the heavy charged states that subsequently thermalize the rest of the dark sector to a temperature much below that of the visible bath. We delineate regions of parameter space consistent with cosmological and astrophysical constraints and identify benchmark scenarios that can guide the next generation of direct detection experiments searching for spin-dependent scattering of sub-GeV dark matter.

Asher Berlin

South Korea

Jae Chang

Tanner Trickle

Infrared freeze-in of magnetic dipole dark matter

The Euclidean formulation of quantum gravity can be interpreted in terms of a probability distribution over Riemannian manifolds. In the context of de Sitter gravity, the statistics of the total volume according to this distribution is encoded in the dependence of the partition function on the cosmological constant. We use this observation to obtain a probability distribution for the volume from known results and proposals for the de Sitter partition function, in several levels of approximation: saddle point, one loop, an all-loop and a non-perturbative proposal in 3 dimensions, and an exact result in 2 dimensions, in the context of Liouville theory. In all cases we find a reasonable behavior: in the classical limit the distribution concentrates around the classical volume, and it spreads as quantum effects are turned on. We also find as a common trend that, as quantum effects are increased, the probability distribution favors increasingly smaller universes.

Argentina

David Blanco

Guillem Pérez-Nadal

Bruno Sivilotti

Euclidean volume fluctuations in de Sitter quantum gravity

We investigate the asymptotic symmetries of asymptotically flat spacetimes at spatial infinity. We propose a new symplectic structure and conservative boundary conditions in a polyhomogeneous Beig–Schmidt expansion. The asymptotic symmetries extend the BMS algebra by abelian sectors, notably incorporating regular log-translations and log-supertranslations. The associated charges are finite and conserved, and we show that their algebra admits a central extension between supertranslations and log-supertranslations, and between the singular translations and regular log-translations. Our analysis is compatible with, and extends, both the work of [1, 2]: it extends the former by incorporating log-supertranslations, and the latter by allowing both parities of the log-supertranslations in the same phase space. These newly identified symmetries at spatial infinity encode novel physical information that has not been revealed in other regions of asymptotically flat spacetimes, thereby opening the door to new observables to consider at null and timelike infinity.