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Related papers: Positivity in Multi-Field EFTs

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Understanding the implication of positivity bounds on loop-generated dim-8 operator coefficients is a nontrivial task, as these bounds only strictly hold when all the contributions are included in the dispersion relation up to a certain…

High Energy Physics - Phenomenology · Physics 2025-10-14 Yunxiao Ye , Xiao Cao , Yu-Hang Wu , Jiayin Gu

We review the effective field theory (EFT) bootstrap by formulating it as an infinite-dimensional semidefinite program (SDP), built from the crossing symmetric sum rules and the S-matrix primal ansatz. We apply the program to study the…

High Energy Physics - Theory · Physics 2024-09-17 Yue-Zhou Li

Parameters in an effective field theory can be subject to certain positivity bounds if one requires a UV completion that obeys the fundamental principles of quantum field theory. These bounds are relatively straightforward at the tree…

High Energy Physics - Phenomenology · Physics 2025-07-22 Yunxiao Ye , Bin He , Jiayin Gu

Effective Field Theory (EFT) extensions of the Standard Model are tools to compute observables $\big(e.g.$ cross sections with partonic center-of-mass energy $\sqrt{\hat{s}}\,\big)$ as a systematically improvable expansion suppressed by a…

High Energy Physics - Phenomenology · Physics 2022-06-07 Timothy Cohen , Joel Doss , Xiaochuan Lu

The virtues of an effective field theory (EFT) approach to many-body problems are illustrated by deriving the expansion for the energy of an homogeneous, interacting Fermi gas at low density and zero temperature. A renormalization scheme…

Nuclear Theory · Physics 2009-11-06 H. -W. Hammer , R. J. Furnstahl

Implications of general properties of quantum field theory, such as causality, unitarity, and locality include constraints on the couplings of the effective field theory (EFT) coefficients. These constraints follow from the connections…

High Energy Physics - Theory · Physics 2025-06-17 Guangzhuo Peng , Long-Qi Shao , Anna Tokareva , Yongjun Xu

Effective Field Theory (EFT) provides a powerful framework that exploits a separation of scales in physical systems to perform systematically improvable, model-independent calculations. Particularly interesting are few-body systems with…

Nuclear Theory · Physics 2009-11-11 H. -W. Hammer

It has been recently proven that the semidefinite programming (SDP) relaxation of the optimal power flow problem over radial networks is exact under technical conditions such as not including generation lower bounds or allowing load…

Optimization and Control · Mathematics 2015-10-19 Burak Kocuk , Santanu S. Dey , X. Andy Sun

In the absence of a theory of everything, modern physicists need to rely on other predictive tools and turned to Effective Field Theories (EFTs) in a number of fields, including but not limited to statistical mechanics, condensed matter,…

High Energy Physics - Theory · Physics 2023-08-17 Victor Pozsgay

Effective Field Theory (EFT) is a general framework to parametrize the low-energy approximation to a UV model that is widely used in model-independent searches for new physics. The use of EFTs at the LHC can suffer from a 'validity' issue,…

High Energy Physics - Phenomenology · Physics 2026-02-03 Spencer Chang , Markus A. Luty , Teng Ma , Francesco Montagno , Andrea Wulzer

The main objective of this work is to isolate Effective Field Theory scattering amplitudes in the space of non-perturbative two-to-two amplitudes, using the S-matrix Bootstrap. We do so by introducing the notion of Effective Field Theory…

High Energy Physics - Theory · Physics 2023-01-18 Joan Elias Miro , Andrea Guerrieri , Mehmet Asim Gumus

We bound EFT coefficients appearing in $2 \to 2$ photon scattering amplitudes in four dimensions. After reviewing unitarity and positivity conditions in this context, we use dispersion relations and crossing symmetry to compute sum rules…

High Energy Physics - Theory · Physics 2022-09-27 Johan Henriksson , Brian McPeak , Francesco Russo , Alessandro Vichi

We establish the bounds on Wilson coefficients of the Higgs effective field theory (HEFT) mandated by unitarity and analyticity. These positivity constraints can be projected into the space of the standard model effective field theory…

High Energy Physics - Phenomenology · Physics 2026-03-02 Grant N. Remmen , Nicholas L. Rodd

We review the effective field theories (EFTs) developed for few-nucleon systems. These EFTs are controlled expansions in momenta, where certain (leading-order) interactions are summed to all orders. At low energies, an EFT with only contact…

Nuclear Theory · Physics 2009-11-07 P. F. Bedaque , U. van Kolck

We develop an Effective Field Theory (EFT) formalism to solve for the conservative dynamics of binary systems in gravity via Post-Minkowskian (PM) scattering data. Our framework combines a systematic EFT approach to compute the deflection…

High Energy Physics - Theory · Physics 2020-12-30 Gregor Kälin , Rafael A. Porto

We introduce an effective field theory (EFT) for conformal impurity by considering a pair of transversely displaced impurities and integrating out modes with mass inversely proportional to the separation distance. This EFT captures the…

High Energy Physics - Theory · Physics 2024-06-11 Oleksandr Diatlyk , Himanshu Khanchandani , Fedor K. Popov , Yifan Wang

Positivity bounds on scattering amplitudes provide a necessary condition for a low-energy effective field theory to have a consistent ultraviolet completion. Their extension to gravity theories has been studied in the past years aiming at…

High Energy Physics - Theory · Physics 2023-08-24 Toshifumi Noumi , Sota Sato , Junsei Tokuda

In this dissertation, I introduce the principles and methods of effective field theory and describe my work in three EFTs: First, in the perturbative QCD region, I use soft collinear effective theory (SCET) to prove that strong interaction…

High Energy Physics - Phenomenology · Physics 2016-12-30 Ou Z. Labun

Broadly speaking, the calculation of core spectra such as electron energy loss spectra (EELS) at the level of density functional theory (DFT) usually relies one of two approaches: conceptually more complex but computationally efficient…

Effective Field Theory (EFT) provides a powerful framework that exploits a separation of scales in physical systems to perform systematically improvable, model-independent calculations. Particularly interesting are few-body systems with…

Other Condensed Matter · Physics 2009-11-10 H. -W. Hammer