Peer Revenue Now accepting positions

Papers

Fresh from arXiv, typeset properly. Highlighted words trade on the market.

Physics High Energy Physics (Theory)

hep-th Watch High Energy Physics (Theory) (sign in to use)

Wednesday 3 June

High Energy Physics (Theory)

Novel $\mathcal{N}=2$ higher-spin supercurrents

We study cubic interactions of $\mathcal N=2$ massless integer-spin gauge supermultiplets in harmonic superspace. We construct the complete class of abelian $(\mathbf{s},\mathbf{s_1},\mathbf{s_2})$ cubic vertices with the minimal number of space-time derivatives. Such vertices exist only for $\mathbf{s}\geq \mathbf{s_1}+\mathbf{s_2}$ and universally take the form of the gauge prepotential coupled to the conserved higher-spin supercurrent. For~$\mathbf{s_1}\neq\mathbf{s_2}$, we find the novel complex principal supercurrent, whose real and imaginary parts generate the parity-invariant and the parity-breaking interactions, respectively. The supercurrents are constructed from gauge-invariant $\mathcal N=2$ higher-spin Weyl supertensors associated with the spin-$\mathbf{s_1}$ and spin-$\mathbf{s_2}$ gauge multiplets. These supertensors are defined in terms of unconstrained higher-spin analytic prepotentials. We also derive the complete set of conserved component higher-spin currents associated with the $(s,s_1,s_2)$ vertices, including both traceless currents and currents with the non-vanishing trace.
Read the full abstract

High Energy Physics (Theory) · Cross-listed from gr-qc

Running Vacuum in the expanding Universe: a unified QFT paradigm for Inflation and Dark Energy

The concordance $\Lambda$CDM model, based on a rigid $\Lambda$-term for the entire cosmic history, has been in crisis for a long time. In our expanding Universe, an evolving $\Lambda$ with the expansion is intuitively much more reasonable. In the running vacuum model (RVM) framework, based on quantum field theory (QFT) in curved spacetime, quantum effects induce a vacuum energy density (VED) $\rho_{\rm vac}=\Lambda/(8\pi G)$ which is a function of the Hubble rate $H$ and its time derivatives, $\rho_{\rm vac}=\rho_{\rm vac}(H, \dot{H},\ddot{H},\dots)$. Currently, $\rho_{\rm vac}$ evolves very slowly with the expansion, $\delta\rho_{\rm vac}\sim {\cal O}(m_{Pl} ^2 H^2)$, and this fact provides a possible fundamental origin of dark energy (DE), conceived as dynamical vacuum energy. In the RVM, Newton's $G$ is also evolving, but much more slowly (logarithmically with $H$): $G=G(\ln H)$. In the very early universe, the vacuum fluctuations induce higher (even) powers, e.g. $\sim H^4$, capable of triggering fast inflation in a very short period, in which $H$ is very large and approximately constant. This is the mechanism of `RVM-inflation'. It does not require an `inflaton' field since inflation is brought about by pure QFT effects on the dynamical background. It differs from Starobinsky's inflation, where $H$ is never constant. Furthermore, the dynamics of $\rho_{\rm vac}(H)$ and $G(H)$ can also have implications on the frequently discussed possibility that the fundamental `constants' of Nature can be mildly evolving with the cosmic expansion. Putting things together, a unified QFT framework of dark energy and inflation ensues as a realistic theory for the description of the universe as a whole on fundamental grounds. In it, dynamical VED is predicted and is much welcomed, since it fits in with current DESI measurements, preferring dynamical DE over a rigid $\Lambda$ term.
Read the full abstract

High Energy Physics (Theory)

Non-linear evolution of five-dimensional black strings in effective field theory

We use numerical relativity to study the non-linear instability of five-dimensional black strings in Einstein-Gauss-Bonnet gravity. Black strings evolve into a series of black holes joined by thinner string-like segments, but key features of the dynamics depend on the sign of the Gauss-Bonnet coupling. For positive coupling, favored by UV considerations, the growth of curvature invariants is limited within the validity of effective field theory (EFT), suggesting a mechanism for restoring weak cosmic censorship. For negative coupling this cap is absent and curvatures may grow until the EFT breaks down.
Read the full abstract

High Energy Physics (Theory)

Mass-Flow Invariance of $Q$-Cohomology in BMN Matrix Quantum Mechanics

We study the dependence of the dynamical supercharges of BMN matrix quantum mechanics on the mass parameter $\mu$. Taking the $\mu$-derivative at fixed canonical matrix variables, we show that the sixteen-component supercharge evolves by the adjoint action of a Hermitian quadratic bosonic operator $\mathcal{K}$, together with the spinor-space factor $i\gamma^{123}$. After projection to a $\gamma^{123}$-eigenspace, this flow integrates to a finite similarity transformation. For the nilpotent component $Q(\mu)=\mathcal Q^4_-(\mu)$, one obtains $Q(\mu)=M(\mu,\mu_0)Q(\mu_0)M(\mu,\mu_0)^{-1}$, giving an algebraic mass-flow non-renormalization statement for the $Q$-cohomology. The corresponding Hilbert-space statement has an analytic qualification, parallel to Witten's argument for supersymmetric quantum mechanics: $M$ is non-unitary and unbounded, so its action on the normalizable domain must be controlled. We formulate a small-step criterion by comparing the quadratic growth of $M$ with the Gaussian falloff of BMN oscillator wavefunctions within each component $\mu>0$ or $\mu<0$. As a concrete check, we evaluate this condition in the $N=2$ theory, whose two vacuum sectors are built on the trivial vacuum and the irreducible fuzzy-sphere vacuum. We also compute the induced $Q_{\rm BPS}$-action on the corresponding BPS letters: in the trivial sector it agrees with the standard BMN-sector BPS-letter differential of $\mathcal{N}=4$ SYM, while in the irreducible sector it vanishes.
Read the full abstract

All authors Chi-Ming Chang, Zhengyuan Du, Sarthak Duary, Kangning Liu, Yi-Xiao Tao

High Energy Physics (Theory) · Cross-listed from hep-lat

Gauge field flow for chiral gauge theories on a slab

The proposal to formulate chiral gauge theories using domain wall fermions on $2n+1$ dimensional Euclidean lattice with a slab geometry involves $2n$ dimensional dynamical gauge fields residing on one of the domain walls. The gauge fields are extended into the extra dimension using gradient flow decoupling the mirror fermions on the anti-wall. We implement this construction on the lattice for $n=1$ in the presence of $2n$ dimensional background gauge fields. We also formulate and implement an additional gauge field flow proposal, where the gauge fields satisfy $2n+1$ dimensional equation of motion away from the domain wall, known as the EOM (equation of motion) flow. In both cases, we couple the gauge fields to fermions and demonstrate how current conservation and anomaly inflow work on the lattice.
Read the full abstract

High Energy Physics (Theory) · Cross-listed from hep-lat

Gauge field flow for chiral gauge theories on a disk boundary

A recent non-perturbative formulation of $2n$ dimensional chiral gauge theories relies on realizing chiral fermions on the $2n$ dimensional boundary of a $2n+1$ dimensional disk manifold. It also requires extending boundary gauge configurations into the interior of the disk using some flow prescription that preserves 2n dimensional gauge invariance. In this paper we propose a concrete realization of the equation of motion flow with the disk embedded on a square lattice. In addition, we couple the flow gauge field to fermions and demonstrate the mechanism of anomaly inflow and anomaly cancellation at work on the lattice.
Read the full abstract

High Energy Physics (Theory)

Krylov Complexity: Flat bands and Carroll breaking deformations

Systems with flat band structures, when written in the language of Compact Localised States (CLS), have been shown to be explicitly invariant under supertranslation symmetries, making Carrollian symmetries inherently important for such systems. In this work, we explore the state dynamics of these systems, focusing on quenches induced by Carroll breaking perturbations, through the probe of Krylov (spread) Complexity. We specialise to Fermionic ladder Hamiltonians with all bands flat (ABF) scenario, augmented by a supertranslation preserving interaction, and discuss Krylov state complexity for quenches across critical lines. We further discuss how the growth of Krylov complexity sharply resolves the phase-dependent resilience of Carrollian sectors against delocalising perturbations. This is augmented by a complementary mechanism for Krylov growth in a continuum Carroll scalar field theory with a gradient deformation, which exhibits strong ultraviolet sensitivity (UV/IR mixing).
Read the full abstract

All authors Aritra Banerjee, Arpan Bhattacharyya, Rudranil Basu, Sayan Das

High Energy Physics (Theory)

Unitarity, Recursion and Soft Limits in (EA)dS through Dressing

Using the recently developed framework in which cosmological correlators in (E)AdS are represented as flat-space amplitudes dressed by auxiliary propagators, we show that several structural properties of the cosmological observables have a direct flat-space origin. We derive cosmological cutting rules for spinning correlators from the flat-space optical theorem, obtain the cosmological tree theorem from the Feynman tree theorem, and uplift BCFW recursion relations to (E)AdS via dressing. We also show that flat-space soft theorems reproduce the soft limits of (E)AdS correlators, and find indications of an emergent universal structure in subleading soft limits. These results provide evidence that key features of cosmological correlators can be systematically understood as dressed manifestations of flat-space physics.
Read the full abstract

High Energy Physics (Theory)

String dualities and wedge singularities

We study strings propagating in backgrounds with a wedge singularity, namely whose internal sector describes a wedge sum of closed manifolds. We focus on the wedge sum of two circles, which was recently argued to provide a quantum geometry for an M-theoretic description of type 0 strings, along with a much wider non-supersymmetric duality web stemming from quotients thereof. In the context of this proposal, we investigate whether the worldsheet features of type IIA strings, together with strong-coupling ingredients, can consistently reproduce the expectation of a weakly coupled type 0A frame. To this end, we combine worldsheet effects due to the wedge singularity with the emergence proposal applied to D0-branes probing it. We find that the resulting potential reproduces the correct tree-level mass of the tachyon in a specific scaling limit. We also discuss the possibility of kinematic obstructions to our worldsheet approach using the framework of topological modular forms, and comment on some puzzles and open questions.
Read the full abstract

High Energy Physics (Theory)

The Double Well Done Doubly-Well

The symmetric double-well potential is one of the simplest quantum-mechanical systems in which perturbative and non-perturbative physics are deeply entangled. Its energy levels have non-analytic expansions in inverse powers of the inter-well separation, with factorially growing coefficients, while the parity splitting is exponentially small and invisible to perturbation theory. Resurgence ties the two features together, organizing the exact spectrum into a single tightly-constrained trans-series. This paper gives a self-contained account of this trans-series from two complementary approaches: exact WKB and the Euclidean path integral, developed in a common notation with explicit calculations through the four-instanton level and three-loop order. In exact WKB, Stokes phenomena encoded in the Delabaere–Dillinger–Pham relations control the analytic continuation of the wavefunction past turning points. The quantization condition expressed in terms of Voros symbols then determines the full trans-series. The DDP relations are local and do not require knowing the global topology of the energy surface, but that surface is an elliptic curve. In the path integral, elliptic curves enter differently: the classical saddle points are doubly-periodic elliptic functions of Euclidean time, and Stokes phenomena play out within the finite-dimensional manifold of quasi-zero modes rather than through analytic continuation of the wavefunction. A Lefschetz thimble decomposition determines which saddles contribute, and the resulting partition function trans-series is much simpler than the energy trans-series: at each instanton order the $T$-dependence is a polynomial fixed by the quasi-zero-mode thimble integrals. Together, the two approaches deploy a shared mathematical infrastructure in complementary ways, showing that the double well is an ideal setting to explore resurgence.
Read the full abstract

High Energy Physics (Theory)

Kaleidoscopes, Waves and the Prepotential

Isomorphic flops are topology-changing transitions connecting two diffeomorphic families of Calabi-Yau threefolds. They correspond to the generators of certain Coxeter groups acting on the moduli space. As a consequence of these symmetries, the prepotential of 4D $\mathcal{N} = 2$ Type IIA compactifications on such varieties must assemble into Coxeter-invariant functions. We construct a database of all Coxeter symmetries from isomorphic flops in Kähler-favorable CICYs. The action of the Coxeter group on the Kähler moduli space leaves a symmetric bilinear form invariant, which we interpret as a metric and construct its associated Laplace-Beltrami operator. We argue that the Coxeter-invariant functions featured in the prepotential solve the Helmholtz equation with this Laplacian, and that the prepotential can then be resummed into a decomposition in terms of eigenfunctions of the Laplace-Beltrami operator. The convergence rate of the raw orbit sums of worldsheet instanton contributions and the resummed expressions are complementary, with the latter sharply localizing around the first few terms in the interior of the moduli space.
Read the full abstract

High Energy Physics (Theory)

Hypergroup Symmetry in Relative Quantum Field Theories and Chiral Algebras

A QFT is said to be relative if it lives at the boundary of a topological QFT in one higher dimension. We develop a general framework for working with noninvertible symmetries of relative theories in two spacetime dimensions, extending several well-known results for absolute QFTs. We emphasize various new features which arise in the relative setting, including the role of topological surfaces of the bulk, and the appearance of hypergroups and certain generalizations of tube algebras known as dome algebras. Our formalism is particularly well-suited for studying rational chiral algebras, where it predicts that finite symmetries are in explicit one-to-one correspondence with conformal embeddings of finite index. We describe several implications of our framework for absolute theories. First, we explain how to "glue" together symmetries of the left- and right-moving chiral algebras of a 2D CFT to produce topological line defects of the full theory. Second, we derive a precise correspondence between boundary conditions of a 2D CFT and symmetries of its chiral algebra. This correspondence has several structural corollaries: in diagonal rational CFTs, we demonstrate that the topological line defects of the theory act transitively on its boundary conditions, and further that the identity Cardy state has the smallest $g$-function amongst all boundary conditions, including those which only preserve Virasoro symmetry. We conclude by illustrating our results in a variety of examples. For instance, we show that, if there exists a rational chiral algebra with central charge $c=8$ whose modular tensor category is the Drinfeld center of the Haagerup fusion category, then it must arise as the fixed points of a rank-2 hypergroup acting on the $SU(3)_1\otimes (E_{6})_1$ chiral algebra.
Read the full abstract

High Energy Physics (Theory) · Cross-listed from hep-ph

Big Axions

We introduce big axions: axion models in which a Nambu-Goldstone mode emerges from the collective spontaneous breaking of a network of U(1) symmetries delocalized in theory space. Big axions naturally realize high-quality accidental global symmetries, admit both pre- and post-inflationary cosmological histories, and exhibit rich topological structures that interpolate between ordinary Peccei-Quinn axions and axions which descend from extra-dimensional gauge fields. We identify a minimal phenomenologically viable subclass, little big axions, and demonstrate that they provide a robust solution to the strong charge-parity problem in quantum chromodynamics while potentially accounting for some or all of the dark matter of the universe.
Read the full abstract

High Energy Physics (Theory)

Thermal Positivity

We argue that Lorentz invariance and unitarity impose sharp constraints on thermodynamic quantities. By relating thermal vacuum diagrams to forward scattering amplitudes, we derive an infinite family of sign conditions on finite-temperature observables in perturbative theories of relativistic massless bosons. In particular, we prove that all low-temperature corrections from interactions to the pressure, or equivalently the negative free energy density, of the form T^{2D-4+4k} with k>0 in D spacetime dimensions, are strictly positive. These positivity conditions are inherited by analogous terms in the entropy density and specific heat. Our results apply to any effective field theory that is free of long-range forces and descends from a weakly coupled ultraviolet completion, in which case higher-loop and higher-multiplicity thermal diagrams are parametrically subleading.
Read the full abstract

High Energy Physics (Theory)

Fermionic Kaluza-Klein mode mixing in braneworlds

We investigate fermionic Kaluza-Klein (KK) mode mixing in thick braneworld models subjected to generic background perturbations. Conventionally, isolated static backgrounds are completely described by a Schroedinger-like formulation, which yields an unperturbed orthogonal basis of KK eigenstates. However, generic perturbations possess a non-trivial spatial profile along the extra dimension. When the full interacting Dirac operator is expanded in this original basis, the spatial variation inevitably yields non-vanishing overlap integrals between distinct KK levels, thereby inducing off-diagonal couplings in the 4D effective mass matrix. Consequently, the original eigenstates are no longer exact physical eigenmodes of the perturbed system. To rigorously preserve the underlying 5D chiral structure and resolve the true physical states, we employ an exact Singular Value Decomposition (SVD) of the full, off-diagonal Dirac mass matrix. Our exact analysis reveals that this mode mixing introduces small but highly structured corrections to the mass eigenvalues. Specifically, parity-odd perturbation operators strictly induce same-parity mixing that preserves the macroscopic Z2 spatial symmetry, whereas parity-even operators trigger cross-parity mixing that shatters the Z2 symmetry, resulting in severe spatial polarization of the KK probability densities. Phenomenologically, such polarization shifts the wave functions toward the brane, turning probability zeros into non-zero values, which directly illuminates previously "dark" KK modes.
Read the full abstract

High Energy Physics (Theory)

Thermal effective action for the $O(N)$ vector model

We compute the leading coefficients of the thermal effective action for the critical O(N) vector model in three dimensions, in the large-N limit in presence of non vanishing angular twist. At high temperature, the partition function on a product of a two-dimensional spatial manifold and a thermal circle admits a Kaluza-Klein reduction to a local effective action on the spatial slice, whose coefficients encode universal CFT data such as the Casimir energy and the response to a Kaluza-Klein gauge field. We determine these coefficients through two independent computations: an evaluation of the twisted partition function on the two-sphere in the high-temperature limit, and a direct path-integral computation on a generic weakly curved background. The two methods yield consistent results, providing a non-trivial check of the thermal effective action framework.
Read the full abstract

High Energy Physics (Theory)

Generalized Heisenberg algebra from $o(2,4)$

It is well known that the algebra $o(2,4)$ generates the conformal group, but it can also be used to define some variants of the Yang model of noncommutative geometry on a curved spacetime. Starting from these examples, we construct a new physical model based on $o(2,4)$, that can be interpreted as a generalization of the Heisenberg algebra on phase space, with flat positions and momenta, but nontrivial commutation relations between positions and momenta and with the Planck constant promoted to an operator.
Read the full abstract

High Energy Physics (Theory) · Cross-listed from astro-ph.CO

Neutrino mass constraints in interacting dark energy models after DESI DR2

Recent DESI observations indicate a deviation from the $\Lambda$CDM model, showing a preference for dynamical dark energy and thereby relaxing the upper limit on the neutrino mass within this framework. This deviation can also be explained by the presence of an interaction between dark energy and dark matter. In this work, we investigate the cosmological upper bounds on the total neutrino mass ($\sum m_{\nu}$) across four different interacting dark energy (IDE) models. The present analysis employs the latest DESI baryon acoustic oscillation, cosmic microwave background, and type Ia supernova datasets. These results demonstrate that the upper bounds on $\sum m_{\nu}$ exhibit profound sensitivity to the specific phenomenological formulation of the interaction term. While the I$\Lambda$CDM2 model ($Q \propto H \rho_{\mathrm{c}}$) substantially relaxes the stringent upper limit ($\sum m_{\nu} < 0.129$ eV at 95% confidence level), notably the I$\Lambda$CDM3 model ($Q \propto H_0 \rho_{\mathrm{de}}$), severely compresses the allowed parameter space, yielding a highly restrictive bound of $\sum m_{\nu} < 0.051$ eV. Furthermore, rigorous goodness-of-fit evaluations utilizing the Deviance Information Criterion and $\Delta\chi^2_{\mathrm{MAP}}$ indicate that the current observational data statistically favor these mass-suppressing IDE models. This establishes an exacerbated statistical tension between the observationally preferred IDE scenarios and the normal hierarchy lower bound ($\sim 0.06$ eV) determined by terrestrial neutrino oscillation experiments.
Read the full abstract

All authors Hui Li, Guo-Hong Du, Tian-Nuo Li, Hai-Li Li, Lu Feng, Jing-Fei Zhang, Xin Zhang

High Energy Physics (Theory)

Path integral quantization of null bosonic strings with Carroll-Weyl ghosts

We revisit the path integral quantization of the null bosonic string from the viewpoint that all local gauge symmetries of the Carrollian worldsheet must be gauge fixed before the quantum theory is defined. In the tensile-string construction the $bc$ ghosts are the Faddeev-Popov determinant for fixing $\mathrm{Diff}\times\mathrm{Weyl}$. In the ILST null string this logic gives the BMS $bc$ system. However, a Carrollian worldsheet admits an additional volume-preserving Carroll-Weyl scaling, whose Hamiltonian generator is $C_3=P\cdot X$. Keeping this scaling as a genuine local gauge symmetry adds one more Faddeev-Popov row. The correct ghost system is therefore a $bcs$ system: the BMS $bc$ ghosts plus a scalar ghost $s$ and scalar antighost $b^s$ for Carroll-Weyl scaling. We derive the revised path integral, the $bcs$-ghost action, its residual symmetry equations, mode expansion, and its relation to the extended BMS algebra. The result changes the BRST complex and the anomaly problem: the usual $D=26$ check based only on the old BMS $bc$ ghosts is a partially gauge-fixed calculation, while the Carroll-Weyl covariant quantum theory must include the $s,b^s$ sector.
Read the full abstract

High Energy Physics (Theory)

Off-shell Thermodynamics and Kinetics of Holographic CFTs Dual to Charged AdS Black Holes

We study the thermodynamics and phase structure of holographic conformal field theories dual to spherically symmetric charged AdS black holes using an off-shell free energy. We consider three ensembles of the dual CFT with fixed: $(\tilde Q,{\cal V},C)$, $(\tilde \Phi,{\cal V},C)$, and $(\tilde Q,{\cal V},\mu)$ and present their corresponding phase diagrams. For the fixed $(\tilde Q,{\cal V},C)$ and $(\tilde \Phi,{\cal V},C)$ ensembles, we study the transitions between competing states using a stochastic description on the various phases given by off-shell free energy. This is described by an ensemble dependent Fokker-Planck equation, allowing us to compute the first-passage-time distribution, including the mean first passage time and its fluctuations over a range of temperatures. We also examine how the phase structure and the associated kinetics depend on the electric charge $\tilde Q$ and the central charge $C$.
Read the full abstract

High Energy Physics (Theory)

AdS$_9$ solutions in type II supergravities

We present new solutions in type II supergravities describing AdS$_9$ geometries warped over an interval. In type IIB, we construct an analytic family of backgrounds supported by a non-trivial axio-dilaton profile. Despite the presence of strong-coupling singularities at both ends of the interval, these solutions exhibit both a finite Euclidean on-shell action and a finite holographic central charge. Moreover, they possess a $\mathbb Z_2$ symmetry under which the axion transforms as $C_0\rightarrow -C_0$. We also investigate AdS$_9$ backgrounds in massive IIA supergravity supported by the Romans mass and the dilaton. Numerical integration reveals solutions with a strong-coupling singularity whose asymptotic behavior is consistent with the characteristic D8/O8 profile. In contrast to the type IIB case, our analysis indicates that the Euclidean on-shell action diverges. Finally, we identify a family of perturbative dS$_9$ solutions in massive IIA supergravity.
Read the full abstract

High Energy Physics (Theory)

$\text{AdS}_D\times I$ solutions in axio-dilaton gravity

We study non-supersymmetric $\mathrm{AdS}_D\times I$ solutions in the context of $(D+1)$ dimensional gravity coupled to an axio-dilaton with arbitrary runaway potential for the dilaton and arbitrary exponential coupling of the dilaton to the axion kinetic energy. We analyze the equations of motion, reformulate them in terms of a first order autonomous dynamical system, and discuss the set of fixed points, their physical interpretation and their stability conditions. We find a few special classes of analytic solutions for arbitrary $D$, including $\mathrm{AdS}_9\times I$ backgrounds in type IIB supergravity. We conclude by discussing the properties of numerical flows including the massive IIA supergravity case.
Read the full abstract

High Energy Physics (Theory) · Cross-listed from astro-ph.CO

Dissipative Dark Energy can explain the DESI phantom crossing

DESI results preferring an evolving dark energy component that appears to cross the phantom-divide in the recent past has raised a lot of interest in exploring the nature of dark energy. We present here a simple dissipative dark energy scenario that can explain both the evolving nature of dark energy as well as its crossing of the phantom-divide without invoking any pathological phantom-like dynamics for the quintessence field. We show that even weak dissipation of the quintessence is enough to explain the current DESI observations.
Read the full abstract

High Energy Physics (Theory)

Resonance transformations for the $(2,2p+1)$ minimal string via $x-y$ swap: a proof of Artemev's conjecture

This paper contains a proof of a recent conjecture of Artemev that connected the resonance transformations for the $(2,2p+1)$ minimal string to the $x-y$ swap in the theory of topological recursion.

High Energy Physics (Theory)

Chiral Transport in Metric-Affine Geometries

Anomalous transport in equilibrium fermionic fluids chirally coupled to background Weyl-type nonmetricity is studied. A formal descent analysis is carried out in which the dependence of the anomaly polynomial on the nonmetricity tensor is encoded in a Weyl invariant four-form. The constitutive relation of the axial-vector current is evaluated from the equilibrium partition function obtained using transgression techniques, showing the existence of nonmetricity-mediated chiral separation effects driven by the fluid's vorticity and the Weyl magnetic field. A second nonminimal coupling of fermionic matter to metric-affine geometries proposed in the literature is also discussed.
Read the full abstract

High Energy Physics (Theory)

Self-dual higher spin theory: Poincaré invariance and new solutions

In this paper we study the self-dual higher spin theory in $4d$ recently proposed in arXiv:2209.01966. The typical vacuum of higher spin theories is an empty AdS space-time. We consider solutions of special form: space-time geometry associated with spin $S=2$ field is an AdS, and other fields may have nonzero values, such that the global space-time symmetry of the vacuum is broken to $3d$ Poincaré. We show that the only field possessing this property is a two-parametric scalar vacuum. We also provide a new family of solutions that generalize this scalar vacuum. In addition to the scalar, the family consists of a fermion $S = 1/2$ in the bulk propagating along the radial direction in Poincaré coordinates and trivial fields of all spins. Fields are trivial in the sense that they do not have gauge fields in the bulk and correspond to trivially conserved currents (i.e. constants) on the conformal boundary.
Read the full abstract

High Energy Physics (Theory) · Cross-listed from cond-mat.mes-hall

Curvature-Controlled Infrared Regularization of Crystalline Membranes

We show that negative Gaussian curvature regularizes the infrared sector of crystalline membranes. In a covariant formulation of embedded elasticity, the Green strain contains a symmetry-required linear coupling between the normal phonon field and extrinsic curvature. Integrating out the in-plane phonons converts this coupling into a finite quadratic contribution to the inverse flexural response. Anomalous roughening is thereby replaced by curvature-controlled saturation, and the mechanism survives on minimal hyperbolic patches. Hyperbolic geometry preempts anomalous elasticity before the flat infrared regime is reached, implying the absence of a crumpling phase at the harmonic level. The same Gaussian-order coupling admits sound propagation in the infrared.
Read the full abstract

High Energy Physics (Theory)

Emergent Closed Universes in Symmetric Orbifold CFTs

We identify closed universe sectors in large $N$ symmetric orbifold CFTs with holographic duals. Starting from tensor product states built out of a finite dimensional low energy subspace of the seed theory, we show that the large $N$ Hilbert space decomposes into superselection sectors labeled by occupation number distributions. Before imposing the orbifold gauge constraint, these sectors have exponentially large dimensions, and the maximally entropic sector dominates the ungauged Hilbert space. We argue that this sector exhibits several characteristic features expected of a closed universe Hilbert space: pure states become indistinguishable from a mixed state at the level of simple correlation functions, and the associated operator algebra is naturally a hyperfinite type II$_1$ von Neumann algebra. We then impose the $S_N$ gauge constraint. The large gauge redundancy drastically reduces the number of independent states. In particular, in the large $N$ limit, the dimension of the physical Hilbert space grows only polynomially with $N$. Consequently, each superselection sector after imposing the constraint is one dimensional in this limit. This reproduces the qualitative behavior suggested by gravitational path integral calculations with wormholes. We then show why, in this setup, the Hartle-Hawking type semiclassical approximation for the dominant closed universe fails to reproduce the CFT results. Nevertheless, the dominant saddle point approximation for gravitational path integral calculation is reconstructed once the CFT degrees of freedom are coupled to external observer degrees of freedom.
Read the full abstract

All authors Akihiro Miyata, Keigo Horikoshi, Hiromasa Tajima, Tomonori Ugajin

High Energy Physics (Theory)

On Cosmologies and Vacua Driven by Tension and Curvatures

We investigate the effects of the exponential potentials typical of non-supersymmetric strings in cosmologies whose spatial and internal slices are maximally symmetric spaces with curvatures labeled by a pair of integers $k$ and $k'$ ($=\pm 1$). We classify the solutions according to their singularity structure and asymptotic behavior and present a semi-quantitative picture of the generic dynamics in the physically most relevant cases with flat spatial slices. The analysis relies on exact solutions emerging when one of the effects dominates, special solutions arising when two or more effects are comparable, scaling asymptotics, and some numerical tests.
Read the full abstract

High Energy Physics (Theory) · Cross-listed from hep-ph

Thermodiffusive coupled-transport phenomena in dense quark matter

Coupled-transport phenomena reveal that heat, charge, and particle flows are intrinsically interconnected, providing deeper insight into the microscopic dynamics of a medium than independent transport processes. We study the behavior of the coupled-transport coefficients in hot and dense quark matter within the framework of the 2+1 flavor Nambu–Jona–Lasinio model at finite temperature and quark chemical potential. These coefficients characterize coupled-transport phenomena, where particle diffusion is driven by temperature gradients (Soret effect) and heat flow is induced by gradients in chemical potential (Dufour effect). These coefficients are estimated by solving the relativistic Boltzmann transport equation using the relaxation time approximation with temperature-dependent cross sections. We study the scaled Soret and Dufour coefficients as functions of temperature and quark chemical potential across the QCD phase diagram. We aim to understand the intricate behavior of the coupled-transport coefficients near the chiral symmetry restoration region. Our results indicate that coupled-transport coefficients are sensitive to the chiral phase transition and provide the first systematic insight into the cross-coupled-transport properties in dense quark matter.
Read the full abstract