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Related papers: On Calculation of Amplitudes in Quantum Electrodyn…

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Amplitudes are the major logical object in Quantum Theory. Despite this fact they presents no physical reality and in consequence only observables can be experimetally checked. We discuss the possibility of a theory of Quantum Probabilities…

Quantum Physics · Physics 2007-05-23 J. M. A. Figueiredo

The explicit computation of amplitudes for fermionic Gaussian pure states in arbitrary Pauli bases is a long-standing challenge in quantum many-body physics, with significant implications for quantum tomography, experimental studies, and…

Quantum Physics · Physics 2025-07-03 M. A. Rajabpour , M. A. Seifi Mirjafarlou , Reyhaneh Khasseh

We extend the recently introduced phaseless auxiliary-field quantum Monte Carlo (QMC) approach to any single-particle basis, and apply it to molecular systems with Gaussian basis sets. QMC methods in general scale favorably with system…

Computational Physics · Physics 2007-05-23 W. A. Al-Saidi , Shiwei Zhang , Henry Krakauer

We present a novel method to determine on the lattice both the real and imaginary parts of complex electroweak amplitudes involving two external currents and a single hadron or the QCD vacuum in the external states. The method is based on…

High Energy Physics - Lattice · Physics 2023-06-13 R. Frezzotti , G. Gagliardi , V. Lubicz , F. Sanfilippo , S. Simula , N. Tantalo

In this paper we show how to measure in the setting of digital quantum simulations the reflection and transmission amplitudes of the one-dimensional scattering of a particle with a short-ranged potential. The main feature of the protocol is…

Quantum Physics · Physics 2024-10-18 Giuseppe Mussardo , Andrea Stampiggi , Andrea Trombettoni

We review some of the modern approaches to scattering amplitude computations in QCD and their application to precision LHC phenomenology. We emphasise the usefulness of momentum twistor variables in parameterising general amplitudes.

High Energy Physics - Phenomenology · Physics 2016-12-21 Simon Badger

The determination of magnitudes of basic parameters of the high energy elastic scattering amplitude are examined at small momentum transfers with taking account of the Coulomb-hadron interference effects.

High Energy Physics - Phenomenology · Physics 2009-11-07 S. B. Nurushev , O. V. Selyugin , M. N. Strikhanov

Attosecond streaking, as a measurement technique, was originally conceived as a means to characterize attosecond light pulses, which is a good approximation if the relevant transition matrix elements are approximately constant within the…

Atomic Physics · Physics 2015-05-19 Vladislav S. Yakovlev , Justin Gagnon , Nicholas Karpowicz , Ferenc Krausz

We present a methodology to price options and portfolios of options on a gate-based quantum computer using amplitude estimation, an algorithm which provides a quadratic speedup compared to classical Monte Carlo methods. The options that we…

High-energy physics simulations traditionally rely on classical Monte Carlo methods to model complex particle interactions, often incurring significant computational costs. In this paper, we introduce a novel quantum-enhanced simulation…

Quantum Physics · Physics 2025-02-28 Euimin Lee , Sangmin Lee , Shiho Kim

A method for computing electromagnetic properties of hadrons in lattice QCD is described. The electromagnetic field is introduced dynamically, using a noncompact formulation. Employing enhanced electric charges, the dependence of the…

High Energy Physics - Lattice · Physics 2009-10-28 A. Duncan , E. Eichten , H. Thacker

Amplitude estimation is a fundamental quantum algorithmic primitive that enables quantum computers to achieve quadratic speedups for a large class of statistical estimation problems, including Monte Carlo methods. The main drawback from the…

We propose a new structure of ensembles in quantum theory, based on the recently introduced intrinsic properties of electrons and photons. On this statistical basis the spreading of a wave-packet, collapse of the wave function, the quantum…

Quantum Physics · Physics 2007-05-23 W. A. Hofer

Quantum computer is extensively used in solving financial problems. Quantum amplitude estimation, an algorithm that aims to estimate the amplitude of a given quantum state, can be utilized to determine the expectation value of bonds as the…

Quantum Physics · Physics 2024-04-09 Jaewoong Heo , Moonjoo Lee

I discuss the recent advances in the computation of two-loop scattering amplitudes for five-particle processes. The latter are fundamental ingredients to obtain predictions at the next-to-next-to-leading order (NNLO) in QCD for many…

High Energy Physics - Phenomenology · Physics 2023-10-09 Simone Zoia

By a mix of form-factors and analyticity techniques, we determine some fundamental scattering amplitudes in non-Fermi liquid systems. These include the reflection and transmission amplitudes for Laughlin quasiparticles at a point contact…

Strongly Correlated Electrons · Physics 2009-11-10 A. Koutouza , F. Lesage , H. Saleur

A simple algorithm is presented to decompose any 1-loop amplitude for scattering processes of the class 2 fermions -> 4 fermions into a fixed number of gauge-invariant form factors. The structure of the amplitude is simpler than in the…

High Energy Physics - Phenomenology · Physics 2009-11-07 Alessandro Vicini

The method for functional reduction of Feynman integrals, proposed by the author, is used to calculate one-loop integrals corresponding to diagrams with four external lines. The integrals that emerge from amplitudes for the scattering of…

High Energy Physics - Phenomenology · Physics 2023-07-12 O. V. Tarasov

An overview of quantum-mechanical methods to generate cross-section data for electron collisions with atoms and molecules is presented. Particular emphasis is placed on the time-independent close-coupling approach, since it is particularly…

Plasma Physics · Physics 2016-10-21 Klaus Bartschat , Jonathan Tennyson , Oleg Zatsarinny

We describe progress applying the \textit{Worldline Formalism} of quantum field theory to the fermion propagator dressed by $N$-photons to study multi-linear Compton scattering processes, explaining how this approach -- whose calculational…