arXiv subjects

Pongwit Srisangyingcharoen

Publications and source records attributed to Pongwit Srisangyingcharoen.

10 recordsLinked to original sources

arXiv2026

No violation on a generalisation of Leggett-Garg inequality and Bell-CHSH inequality with extended probability

A generalisation of the Leggett-Garg inequality (LGI) and the Bell-CHSH inequality is proposed in this work, by replacing a classical probability notion with an extended probability notion. The extended probability serves as an underlying layer of reality to the classical probability. Within the consistent history framework, the underlying layer is so-called a non-settleable history. Hence, the bounds of the LGIs and Bell-CHSH inequalities are extended. The resulting generalised inequalities are satisfied without violation for arbitrary measurement settings. Furthermore, generalised Macro- realism and generalised Local realism are introduced and analysed within the extended probability framework without relying on an explicit measurement. This opens up further possibilities on one of the great pursuits in physics, understanding on how a quantum system can possess classical properties.

quant-ph↗

arXiv2026

From AdS Propagators to Celestial Propagators

In this paper, we investigate how AdS scalar propagators are represented in the celestial basis. Starting from the standard bulk-to-boundary propagator in Euclidean AdS space, we express the propagator in a Schwinger parametrization and construct the corresponding boundary-to-boundary propagator. We then transform the resulting propagators to the celestial basis using conformal primary wavefunctions for both massless and massive scalar fields. For the massless case, the celestial propagator reduces to an effectively two-dimensional boundary-to-boundary object on the celestial sphere dependent on the AdS/CFT conformal dimension $Δ$ as a scaling factor. For the massive case, the celestial propagator exhibits a nontrivial kernel involving modified Bessel functions, closely resembling the momentum-space radial structure of AdS bulk-to-boundary propagators. The results suggest a structural translation from AdS propagators and celestial propagators.

hep-th↗

arXiv2026

Integral Transformations for Conformally Invariant Celestial Amplitudes

We propose an integral transformation for celestial gluon amplitudes that maps the celestial coordinates $(z_i,\bar z_i)$ to a new set of complex variables $(s_i,\bar s_i)$, inspired by the structure of closed string scattering amplitudes. A consistent inverse transformation is constructed by regulating a divergence associated with translational redundancy and absorbing it into an overall normalization. Applying this transformation to celestial MHV amplitudes, we derive constraints on $(s_i,\bar s_i)$ for three-, four-, and general $n$-point amplitudes, and show that these conditions are necessary for invariance under global conformal transformations.

hep-th↗

arXiv2025

Two-point tree-level string amplitudes as AdS transition amplitudes

We compute the two-point open string and closed string amplitudes at tree level and show that, in a 't Hooft-like limit, they take a form structurally analogous to boundary-to-boundary transition amplitudes of a scalar field in Euclidean AdS space. Interestingly, while both amplitudes yield equivalent expressions, the associated 't Hooft couplings are defined by different worldsheet curvatures-geodesic for the disk and Gaussian for the sphere-suggesting a possible geometric aspect of open/closed string duality.

hep-th↗

arXiv2025

On-shell Recursion Relations for Tree-level Closed String Amplitudes

We derive a general expression for on-shell recursion relations of closed string tree-level amplitudes. Starting with the string amplitudes written in the form of the Koba-Nielsen integral, we apply the BCFW shift to deform them. In contrast to open string amplitudes, where poles are explicitly determined by the integration over vertex positions, we utilize Schwinger's parametrization to handle the pole structure in closed strings. Our analysis reveals that the shifted amplitudes contain $δ$-function poles, which yield simple poles upon taking residues. This allows us to present a general expression for the on-shell recursion relation for closed strings. Additionally, we offer an alternative method for computing the residue of the shifted amplitudes by factorizing an $n$-point closed string amplitude into two lower-point amplitudes. This is achieved by inserting a completeness relation that includes all possible closed string states in the Fock space. Our results are consistent with those previously obtained.

hep-th↗

arXiv2024

General Expressions for On-shell Recursion relations for Tree-level Open String Amplitudes

In this paper, we present a systematic derivation aimed at obtaining general expressions for on-shell recursion relations for tree-level open string amplitudes. Our approach involves applying the BCFW shift to an open string amplitude written in terms of multiple Gaussian hypergeometric functions. By employing binomial expansions, we demonstrate that the shifted amplitudes manifest simple poles, which correspond to scattering channels of intermediate states. Using the residue theorem, we thereby derive a general expression for these relations.

hep-th↗

arXiv2024

Relations between closed string amplitudes and mixed string amplitudes at tree-level

This paper investigates the relationships between closed and mixed string amplitudes at the tree level in string theory. Through the analytic continuation of complex variables, we establish a factorization of closed string amplitudes into those involving ($n-2$) open strings and a single closed string. Expressions for four-, five-, and six-point amplitudes are provided, along with systematic formulations for $n$ strings. The paper addresses possible correction terms arising from integration along infinite tubes during the Wick rotation process. In the field theory limit, the correction terms become negligible due to being of subleading order.

hep-th↗

arXiv2023

Steps Towards Generalization of Tensionless String Theory with Contact Interactions as Wilson loop of Non-Abelian Yang-Mills Theory

We propose a possible modification to the tensionless string model with contact interactions. The proposed model aims to reproduce an expectation value of the non-Abelian Wilson loop in the Yang-Mills theory when integrating out string degrees of freedom with a fixed worldsheet boundary. Lie algebra-valued fields whose dynamics are determined by the topological BF action are introduced on the string worldsheet to reproduce path-ordering along the worldsheet boundary. Without bulk contributions, we show that the model describes the non-Abelian Wilson loop discarding effects of self-interactions. Finally, a reproduction of the Wilson loop with three-point interaction is tested in the case of $SU(2)$

hep-th↗

arXiv2021

Effective Lagrangian for Non-Abelian Two-Dimensional Topological Field Theory

We develop a systematic approach to obtain an effective Lagrangian for 2D non-Abelian topological BF theory. A general expression is presented in a diagrammatic representation containing solely scalar fields. Expressions for the SU(2) and SU(3) effective actions are explicitly stated. In the case of SU(2), we show that the effective action can be interpreted as a winding number. By using the SU(2) effective action, the partition function on a sphere for SU(2) Yang-Mills theory is calculated. Moreover, we generalise the theory to include a source term for the gauge field as well as calculate the vacuum expectation value of the Wilson loop based on the effective theory.

hep-th↗

arXiv2021

Plahte Diagrams for String Scattering Amplitudes

Plahte identities are monodromy relations between open string scattering amplitudes at tree level derived from the Koba-Nielsen formula. We represent these identities by polygons in the complex plane. These diagrams make manifest the appearance of sign changes and singularities in the analytic continuation of amplitudes. They provide a geometric expression of the KLT relations between closed and open string amplitudes. We also connect the diagrams to the BCFW on-shell recursion relations and generalise them to complex momenta resulting in a relation between the complex phases of partial amplitudes.

hep-th↗