We examine quantum mutual information (QMI) extraction through local interactions of three Unruh–DeWitt detectors with the vacuum massless scalar field, comparing scenarios with and without gravitational wave perturbations in Minkowski spacetime. Our analysis reveals that gravitational waves can either enhance or diminish tripartite QMI compared to the flat spacetime case, demonstrating their dual capacity to amplify or suppress tripartite QMI harvesting. A significant resonance phenomenon emerges when detector energy gaps match the gravitational wave frequency. Furthermore, when harvesting a certain amount of tripartite QMI, gravitational wave modifies the spatial parameters for effective tripartite QMI harvesting: the achievable separation range undergoes extension or contraction depending on three critical parameters-detector energy gap, gravitational wave frequency, and the duration of the gravitational wave interaction.

China

Si-Yu Liu

Xiao-Li Huang

Shu-Min Wu

The influence of gravitational wave on tripartite quantum mutual information harvesting

The universal relations in neutron stars form an essential entity to understand their properties. The moment of inertia, dimensionless tidal deformability, mass quadrupole moment, and oscillation modes are some of the properties that have been studied previously in the context of universal relations. All of these quantities are measurable; thus, analyzing them is of utmost importance. In this article we provide new universal relations in the context of a neutron star’s gravitational redshift. Using the redshift measurements of RBS 1223, RX J0720.4-3125, and RX J1856.5-3754, we provide theoretical estimates of moment of inertia, dimensionless tidal deformability, mass quadrupole moment, the mass of the star times the ratio of angular frequency over the spin angular moment, and the average of the speed of sound squared. In the case of the redshift measurement of RX J0720.4-3125, we found that the theoretical estimate using universal relations aligns closely with the Bayesian estimate. Our findings indicate that such theoretical predictions are highly reliable for observations with low uncertainty and can be used as an alternative for statistical analysis. Additionally, we report a violation of the universality of the dimensionless tidal deformability and average of the speed of sound squared with respect to the gravitational redshift. Our calculations further indicate that, under current astrophysical constraints, the maximum gravitational redshift attainable by neutron stars does not exceed 0.763.

India

Sagnik Chatterjee

Kamal Nath

Insights into neutron stars from gravitational redshifts and universal relations

A confining extension of the quark model with nonlocal currents is proposed. The quark propagator is modified by introducing a cut in $$\alpha $$ -space, which in momentum space corresponds to the subtraction of pole singularities. A two-phase structure is proposed for modeling the confinement-deconfinement phase transition. In the confined phase, the quark propagator does not have any pole singularities, while in the deconfined phase, there is a single quark pole.

Russia

A. Radzhabov

X. Shang

Confining modeling of quark propagator

We examine the concept of temperature in non-equilibrium steady states. Using the D3-D5 model of gauge/gravity duality, we investigate spontaneous symmetry breaking in a relativistic (2 + 1)-dimensional defect moving at constant velocity within a (3 + 1)-dimensional heat bath. We find that the dependence of the order parameter on both the heat bath temperature and the defect velocity can be captured by a single variable — the proper effective temperature — for the moving defect. Our results suggest that the proper effective temperature is an essential parameter for a class of relativistic non-equilibrium steady states.

Japan

Shin Nakamura

Fuminori Okabayashi

Proper effective temperature and order parameters in relativistic non-equilibrium steady states

We demonstrate a unified resolution to the strong CP, hierarchy, and cosmological constant problems in type IIA flux compactifications, via 4-form fluxes and KL stabilization. We show that the strong CP problem can be effectively “solved” in type IIA orientifold constructions, particularly in the type IIA $\textit{T}$ /($\textit{ℤ}$ × $\textit{ℤ}$ ) model. Building on this, we explore whether the remaining two fine-tuning problems can also be resolved within the same setup. To obtain a small cosmological constant, we adopt the KL scenario and find that, in order to avoid conflicts with the swampland distance conjecture and to eliminate the need for fine-tuning, the perturbative superpotential ∆$\textit{W}$ must take the form $\textit{f}$ $\textit{U}$ . Additionally, we compute the gravitino mass. This allows for a resolution of the hierarchy problem without introducing fine-tuning if gravitino mass lies below 100 TeV. Taken together, these results suggest that the type IIA $\textit{T}$ /($\textit{ℤ}$ × $\textit{ℤ}$ ) orientifold model provides a promising framework in which all three fine-tuning problems may be addressed simultaneously.

United Kingdom

Yang Liu

Fine-tuning problems in type IIA string theory

Quantum field theory on two- and three-dimensional fuzzy anti-de Sitter spaces is introduced and studied. We find a complete set of solutions to the fuzzy Klein-Gordon equation and identify the commutative limit in which they reduce to classical scalar field modes. After introducing the noncommutative boundary via semi-classical states, the fuzzy modes are used to obtain the boundary two-point function. In both two and three dimensions, this gives an interesting two-parameter deformation of the conformal two-point function. For the fuzzy AdS , the two-point function is given explicitly in terms of the Appell function $\textit{F}$ .

Serbia

Bojana Brkić

Ireland

Ilija Burić

Maja Burić

Dušan Ðorđević

Duško Latas

QFT on fuzzy AdS spaces: classical limit and boundary correlation functions

Quantum field theories with quenched disorder are so hard to study that even exactly solvable free theories present puzzling aspects. We consider a free scalar field $\textit{ϕ}$ in $\textit{d}$ dimensions coupled to a random source $\textit{h}$ with quenched disorder. Despite the presence of a mass scale governing the disorder distribution, we derive a new description of the theory that allows us to show that the theory is gapless and invariant under conformal symmetry, which acts in a non-trivial way on $\textit{ϕ}$ and $\textit{h}$. This manifest CFT description reveals the presence of exotic continuous symmetries, such as nilpotent bosonic ones, in the quenched theory. We also reconsider Cardy’s CFT description defined through the replica trick. In this description, the nilpotent symmetries reveal a striking resemblance with Parisi-Sourlas supersymmetries. We provide explicit maps of correlation functions between such CFTs and the original quenched theory. The maps are non-trivial and show that conformal behaviour is manifest only when considering suitable linear combinations of averages of products of correlators. We also briefly discuss how familiar notions like normal ordering of composite operators and OPE can be generalized in the presence of the more complicated local observables in the quenched theory.

Italy

Alessandro Piazza

Marco Serone

France

Emilio Trevisani

The random free field scalar theory

We elaborate on the method introduced in arXiv:2403.02165 for holographic duals of Boundary Conformal Field Theories (BCFTs) with multiple boundaries. Naïvely, as the number of boundaries grow large such a calculation becomes unmanageable. We show that is not always the case. Using these advances we calculate the entanglement entropy as a function of time for 1+1-dimensional CFTs that are split into $\textit{N}$ subsystems. We give explicit results for $\textit{N}$ = 4 and $\textit{N}$ = 17. We find that all qualitative differences that arise for larger $\textit{N}$ are present $\textit{N}$ = 4.

United States

Belgium

Joseph Lap

Berndt Müller

Germany

Andreas Schäfer

Clemens Seidl

Holography for BCFTs with multiple boundaries: multi-splitting quenches

Identifying a full basis of operators to a given order is key to the generality of Effective Field Theory (EFT) and is by now a problem of known solution in terms of the Hilbert series. The present work is concerned with hidden symmetry in general and Higgs EFT in particular and $\textit{(i)}$ connects the counting formula presented in [1] in the CCWZ formulation with the linear frame and makes this connection explicit in HEFT $\textit{(ii)}$ outlines the differences in perturbation theory in each frame $\textit{(iii)}$ presents a new counting formula with measure in the full SU(3) × SU(2) × U(1) group for HEFT and $\textit{(iv)}$ provides a Mathematica code that produces the number of operators at the user-specified order in HEFT.

Rodrigo Alonso

Shakeel Rahaman

Counting and building operators in theories with hidden symmetries and application to HEFT

We derive two rigorous bounds on the spectrum of massive states that contributes to planar amplitudes in weakly coupled theories with massless scalars. First, we show that the presence of massive spinning states necessitates the existence of lighter states with lower spins. Explicitly, if there exists a massive state with spin $\textit{J}$ > 2, then there must be a state with spin $\textit{J}$ − 1 and a non-zero mass lower than that of the lightest spin-$\textit{J}$ state, a state with spin $\textit{J}$ − 2 and a mass lower than that of the lightest spin-($\textit{J}$ − 1) particle and so on until we reach a mass below which only states with spin less than 2 are exchanged. Second, we find that if there are spin-$\textit{J}$ states in the spectrum, the maximum mass of the lightest spin-($\textit{J}$ + 1) state is determined by the masses of the lightest spin-$\textit{J}$ and ($\textit{J}$ − 1) states. In the approximation that this bound applies to pion scattering in real world QCD, we find it gives a window of only ∼150 MeV for the expected mass of a yet unmeasured spin-7 meson.

Justin Berman

Analytic bounds on the spectrum of crossing symmetric S-matrices