arXiv subjects

Zizheng Zhou

Publications and source records attributed to Zizheng Zhou.

5 recordsLinked to original sources

arXiv2026

Static-Recoil Factorization in Heavy-Baryon Chiral EFTs

Extending heavy-baryon \(χ\)PT to higher-spin resonances introduces unphysical lower-spin admixtures, leading to costly path-integral projections. To resolve this, we develop an on-shell implementation of the heavy-baryon expansion based on recoil-channel partial-wave eigenoperators. These eigenoperators separate the static mass dependence from recoil structures and assign chiral order directly in amplitude space. The resulting static--recoil factorization systematically generates non-redundant local operators for heavy-baryon sectors involving higher-spin resonances. Flavor structures and identical-particle constraints are imposed through a new linear-algebraic reduction that uses von Neumann alternating projections to extract the corresponding common physical subspace. Beyond this specific application, the framework can be broadly applied to general nonrelativistic effective field theories.

hep-ph↗

arXiv2026

An Efficient On-shell Framework for EFT Matching

Standard techniques for one-loop EFT matching often have gauge and basis redundancies, while strictly 4-dimensional on-shell methods fail to capture rational terms. To resolve this, we develop an efficient, channel-based on-shell framework for one-loop matching. Our method reconstructs the local hard-region amplitude by sewing tree amplitudes across double cuts, employing a mass-shift prescription to recover d-dimensional internal states. This d-dimensional sewing retains rational terms and integrates them seamlessly with ordinary cut-constructible contributions. The local amplitude is expanded in the hard region and directly projected onto non-redundant, on-shell EFT amplitude bases. With tadpoles and kinematically independent bubbles systematically fixed by an explicit subtraction convention, our framework successfully merges the rigorous extraction of rational Wilson coefficients with the gauge-invariant elegance of modern amplitude methods.

hep-ph↗

arXiv2025

Interacted Object Grounding in Spatio-Temporal Human-Object Interactions

Spatio-temporal Human-Object Interaction (ST-HOI) understanding aims at detecting HOIs from videos, which is crucial for activity understanding. However, existing whole-body-object interaction video benchmarks overlook the truth that open-world objects are diverse, that is, they usually provide limited and predefined object classes. Therefore, we introduce a new open-world benchmark: Grounding Interacted Objects (GIO) including 1,098 interacted objects class and 290K interacted object boxes annotation. Accordingly, an object grounding task is proposed expecting vision systems to discover interacted objects. Even though today's detectors and grounding methods have succeeded greatly, they perform unsatisfactorily in localizing diverse and rare objects in GIO. This profoundly reveals the limitations of current vision systems and poses a great challenge. Thus, we explore leveraging spatio-temporal cues to address object grounding and propose a 4D question-answering framework (4D-QA) to discover interacted objects from diverse videos. Our method demonstrates significant superiority in extensive experiments compared to current baselines. Data and code will be publicly available at https://github.com/DirtyHarryLYL/HAKE-AVA.

cs.CV↗

arXiv2024

Dark Photons and Gravitino Like Particles: Complete EFT Operator Basis

We present a more efficient method for constructing the complete EFT operator basis for particles of any mass and spin, based on on-shell method and Young tableaux. By classifying the amplitude bases according to the polarization configurations of massive particles and using their high-energy limit, our approach can construct EFT basis in a straightforward way, without need of auxiliary fields and tedious basis decomposition. Based on this improved method, we develop a Mathematica code that can automatically construct the EFT basis for particles of any spin. As applications, the EFT bases up to d=8 are explicitly constructed for dark photons and, for the first time, for spin-3/2 gravitino like particles.

hep-ph↗

arXiv2024

Bridging the Gap between Human Motion and Action Semantics via Kinematic Phrases

Motion understanding aims to establish a reliable mapping between motion and action semantics, while it is a challenging many-to-many problem. An abstract action semantic (i.e., walk forwards) could be conveyed by perceptually diverse motions (walking with arms up or swinging). In contrast, a motion could carry different semantics w.r.t. its context and intention. This makes an elegant mapping between them difficult. Previous attempts adopted direct-mapping paradigms with limited reliability. Also, current automatic metrics fail to provide reliable assessments of the consistency between motions and action semantics. We identify the source of these problems as the significant gap between the two modalities. To alleviate this gap, we propose Kinematic Phrases (KP) that take the objective kinematic facts of human motion with proper abstraction, interpretability, and generality. Based on KP, we can unify a motion knowledge base and build a motion understanding system. Meanwhile, KP can be automatically converted from motions to text descriptions with no subjective bias, inspiring Kinematic Prompt Generation (KPG) as a novel white-box motion generation benchmark. In extensive experiments, our approach shows superiority over other methods. Our project is available at https://foruck.github.io/KP/.

cs.CV↗