Journal of High Energy Physics最新文献

The method of regions is an approach for developing asymptotic expansions of Feynman Integrals. We focus on expansions in Euclidean signature, where the method of regions can also be formulated as an expansion by subgraph. We show that for such expansions valid around small/large masses and momenta the graph combinatorial operations can be formulated in terms of what we call the asymptotic Hopf algebra. This Hopf algebra is closely related to the motic Hopf algebra underlying the R^∗ operation, an extension of Bogoliubov’s R operation, to subtract both IR and UV divergences of Feynman integrals in the Euclidean. We focus mostly on the leading power, for which the Hopf algebra formulation is simpler. We uncover a close connection between Bogoliubov’s R operation in the Connes-Kreimer formulation and the remainder ( mathcal{R} ) of the series expansion, whose Hopf algebraic structure is identically formalised in the corresponding group of characters. While in the Connes-Kreimer formulation the UV counterterm is formalised in terms of a twisted antipode, we show that in the expansion by subgraph a similar role is played by the integrand Taylor operator. To discuss the structure of higher power expansions we introduce a novel Hopf monoid formulation.

We present an analytic calculation of three-loop four-point Feynman integrals with two off-shell legs of equal mass. We provide solutions to the canonical differential equations of two integral families in both Euclidean and physical regions. They are validated numerically against independent computations. A total of 170 master integrals are expressed in terms of multiple polylogarithms up to weight six. Most of them are computed for the first time. Our results are essential ingredients of the scattering amplitudes for equal-mass diboson production at next-to-next-to-next-to-leading-order QCD at the LHC.

Gravitational echoes can be used to probe the structure of spacetime. In this paper, we investigate the gravitational echoes in different braneworld models in five-dimensional spacetime. We derive the gravitational perturbation equations of these models, and obtain the time-dependent evolution equations of the extra-dimensional and radial components. Using a Gaussian wave packet as initial data, we study the time evolution of the gravitational perturbation. By monitoring the evolution of the Gaussian wave packet, the gravitational echoes are observed whether the wave packet is generated from inside or outside the braneworld. Furthermore, we can restrict the parameters of the braneworld by calculating the strength of the first gravitational echo and using the current gravitational wave data.

It has long been known that the maximal cut of the equal-mass four-loop banana integral is a period of a family of Calabi-Yau threefolds that depends on the kinematic variable z = m²/p². We show that it can also be interpreted as a period of a family of genus-two curves. We do this by introducing a general Calabi-Yau-to-curve correspondence, which in this case locally relates the original period of the family of Calabi-Yau threefolds to a period of a family of genus-two curves that varies holomorphically with the kinematic variable z. In addition to working out the concrete details of this correspondence for the equal-mass four-loop banana integral, we outline when we expect a correspondence of this type to hold.

We investigate the bulk reconstruction of AdS black hole spacetime emergent from quantum entanglement within a machine learning framework. Utilizing neural ordinary differential equations alongside Monte-Carlo integration, we develop a method tailored for continuous training functions to extract the general isotropic bulk metric from entanglement entropy data. To validate our approach, we first apply our machine learning algorithm to holographic entanglement entropy data derived from the Gubser-Rocha and superconductor models, which serve as representative models of strongly coupled matters in holography. Our algorithm successfully extracts the corresponding bulk metrics from these data. Additionally, we extend our methodology to many-body systems by employing entanglement entropy data from a fermionic tight-binding chain at half filling, exemplifying critical one-dimensional systems, and derive the associated bulk metric. We find that the metrics for a tight-binding chain and the Gubser-Rocha model are similar. We speculate this similarity is due to the metallic property of these models.

We present an analysis of lepton-jet azimuthal decorrelation in deep-inelastic scattering (DIS) at next-to-next-to-next-to-leading logarithmic (N³LL) accuracy, combined with fixed-order corrections at ( mathcal{O}left({alpha}_s^2right) ). In this study, jets are defined in the lab frame using the anti-k_T clustering algorithm and the winner-take-all recombination scheme. The N³LL resummation results are derived from the transverse-momentum dependent factorization formula within the soft-collinear effective theory, while the ( mathcal{O}left({alpha}_s^2right) ) fixed-order matching distribution is calculated using the NLOJET++ event generator. The azimuthal decorrelation between the jet and electron serves as a critical probe of the three-dimensional structure of the nucleon. Our numerical predictions provide a robust framework for precision studies of QCD and the nucleon’s internal structure through jet observables in DIS. These results are particularly significant for analyses involving jets in HERA data and the forthcoming electron-ion collider experiments.

Asymptotic symmetries are known to constrain the infrared behaviour of scattering processes in asymptotically flat spacetimes. By the same token, one expects symmetries of the black hole horizon to constrain near-horizon gravitational scattering. In this paper, we take a step towards establishing this connection. We find all near-horizon symmetries that can be potentially relevant to gravitational scattering near the horizon of the Schwarzschild black hole. We study large diffeomorphisms of linearised perturbations of the Schwarzschild black hole in a partial wave basis and in a gauge that allows for gravitational radiation crossing the event horizon. This setup is ideally suited for studying processes involving near-horizon gravitons like scattering and black hole evaporation. We find the most general near-horizon symmetries that are consistent with finite perturbations at the horizon. Since we do not impose any further boundary conditions, these symmetries represent the biggest set of symmetries in this setting. We find the associated covariant charges to be finite and non-zero showing that these symmetries are physical. Interestingly, for a large black hole, the dominant symmetries are just two copies of u(1).

We consider 4d ( mathcal{N} ) = 4 SU(N) super Yang-Mills on half-space with boundary conditions defined by configurations of Gaiotto-Witten NS5- and D5-branes modded out by a rotated orientifold 5-plane breaking an extra half of the supersymmetries. We focus on configurations in which this O5’-brane is split by an NS5-brane into two oppositely charged halves, leading to a breaking of supersymmetry down to 3d ( mathcal{N} ) = 2 at the local level. The 5-brane configurations turn into non-trivial (p, q) webs and lead to non-trivial brane and gauge theory phenomena, including a 5d Z₂ global gauge anomaly cancelled by a novel 6d global anomaly inflow, and the appearance of localized 3d ( mathcal{N} ) = 2 Chern-Simons couplings and the 3d parity anomaly at the boundary of the 4d theory. The systems have explicit gravity duals, given by orientifolds of the AdS₄ × S² × S² fibrations over a Riemann surface dual to the Gaiotto-Witten setups. They describe solutions with an asymptotic AdS₅ × S⁵ terminating at AdS₄ End of the World boundary configurations, whose rich dynamics reproduces the above physical properties. They also provide the SymTFT of the 4d ( mathcal{N} ) = 4 on half-space with a new class of boundary conditions. We explore the interplay of bulk and boundary topological couplings and draw general lessons for the classification of cobordism defects of bulk quantum gravity theories in the swampland program.

We propose a holographic dual of boundary conformal field theory (BCFT) with ( Toverline{T} ) deformation, i.e. of ( Toverline{T} ) BCFT. Our holographic proposal distinguishes two types of ( Toverline{T} ) BCFTs, depending on whether the ( Toverline{T} ) deformation deforms the boundary. For the boundary-deformed case, we find that boundary entropy serves as an effective measure to quantify the impact of boundary deformation. In this scenario, we calculate the energy spectrum for the ( Toverline{T} ) BCFT within a finite interval to support the proposed dual. For the boundary-undeformed case, we calculate the entanglement entropy and Rényi entropy from both the field theory side and the gravity side, and find that they match.