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Related papers: Quasi-classical alternatives in quantum chemistry

200 papers

Polaritonic chemistry has ushered in new avenues for controlling molecular dynamics. However, two key questions remain: (i) Can classical light sources elicit the same effects as certain quantum light sources on molecular systems? (ii) Can…

Quantum Physics · Physics 2023-12-13 Leonardo F. Calderón , Humberto Triviño , Leonardo A. Pachón

One of the central problems in quantum theory is to characterize, detect, and quantify quantumness in terms of classical strategies. Dephasing processes, caused by non-dissipative information exchange between quantum systems and…

Quantum Physics · Physics 2019-08-23 Hong-Bin Chen , Ping-Yuan Lo , Clemens Gneiting , Joonwoo Bae , Yueh-Nan Chen , Franco Nori

The development of tailored materials for specific applications is an active field of research in chemistry, material science and drug discovery. The number of possible molecules that can be obtained from a set of atomic species grow…

Combining quantum computers with classical compute power has become a standard means for developing algorithms that are eventually supposed to beat any purely classical alternatives. While in-principle advantages for solution quality or…

Quantum Physics · Physics 2026-01-23 Simon Thelen , Wolfgang Mauerer

A new form of quasiclassical space-time dynamics for constrained systems reveals how quantum effects can be derived systematically from canonical quantization of gravitational systems. These quasiclassical methods lead to additional fields,…

General Relativity and Quantum Cosmology · Physics 2024-01-04 Kallan Berglund , Martin Bojowald , Manuel Diaz , Gianni Sims

First principles based exploration of chemical space deepens our understanding of chemistry, and might help with the design of new materials or experiments. Due to the computational cost of quantum chemistry methods and the immens number of…

Chemical Physics · Physics 2020-08-18 Bing Huang , O. Anatole von Lilienfeld

Severe methodological and numerical problems of the traditional quantum mechanical approach to the description of molecular systems are outlined. To overcome these, a simple alternative to the Born-Oppenheimer approximation is presented on…

Chemical Physics · Physics 2014-02-06 Irmgard Frank

The rules of canonical quantization normally offer good results, but sometimes they fail, e.g., leading to quantum triviality ($=$ free) for certain examples that are classically nontrivial ($\ne$ free). A new procedure, called Enhanced…

Quantum Physics · Physics 2018-11-26 John R. Klauder

Quantum algorithms for electronic-structure simulations are actively being developed, yet many hybrid quantum-classical approaches are bottlenecked by the measurement overhead associated with large molecular Hamiltonians. Here we introduce…

Quantum Physics · Physics 2026-03-10 Benjamin Mokhtar , Noboru Inoue , Takashi Tsuchimochi

Without wasting time and effort on philosophical justifications and implications, we write down the conditions for the Hamiltonian of a quantum system for rendering it mathematically equivalent to a deterministic system. These are the…

Quantum Physics · Physics 2020-06-09 Gerard t Hooft

This paper is a generalization of previous work on the use of classical canonical transformations to evaluate Hamiltonian path integrals for quantum mechanical systems. Relevant aspects of the Hamiltonian path integral and its measure are…

High Energy Physics - Theory · Physics 2009-10-28 Mark S. Swanson

The classical invariants of a Hamiltonian system are expected to be derivable from the respective quantum spectrum. In fact, semiclassical expressions relate periodic orbits with eigenfunctions and eigenenergies of classical chaotic…

Chaotic Dynamics · Physics 2009-10-31 Diego. A. Wisniacki , Eduardo Vergini

We propose a new methodology, called numerical canonical quantization, to solve quantum Maxwell's equations useful for mathematical modeling of quantum optics physics, and numerical experiments on arbitrary passive and lossless…

Quantum Physics · Physics 2020-08-26 Dong-Yeop Na , Jie Zhu , Fernando L. Teixeira , Weng C. Chew

Improving the efficiency and accuracy of energy calculations has been of significant and continued interest in the area of materials informatics, a field that applies machine learning techniques to computational materials data. Here, we…

Quantum Physics · Physics 2021-02-03 Tanvi P. Gujarati , Tyler Takeshita , Andreas Hintennach , Eunseok Lee

Classical algorithms for predicting the equilibrium geometry of strongly correlated molecules require expensive wave function methods that become impractical already for few-atom systems. In this work, we introduce a variational quantum…

The practical application of quantum technologies to chemical problems faces significant challenges, particularly in the treatment of realistic basis sets and the accurate inclusion of electron correlation effects. A direct approach to…

We study the Hydrogen atom as a quantum mechanical system with a Coulomb like potential, with a semiclassical approach based on an effective description of quantum mechanics. This treatment allows us to describe the quantum state of the…

Quantum Physics · Physics 2012-03-23 Guillermo Chacón-Acosta , Héctor H. Hernández

We continue our efforts to understand, within the framework of the quantum mechanics of the universe as a whole, the quasiclassical realm of familiar experience as a feature emergent from the Hamiltonian of the elementary particles and the…

Quantum Physics · Physics 2019-05-16 Murray Gell-Mann , James Hartle

The numerical treatment of quantum mechanics in the semi-classical regime is known to be computationally demanding, due to the highly oscillatory behaviour of the wave function and its large spatial extension. A recently proposed…

Quantum Physics · Physics 2024-02-13 Christoph Nölle

A general method of quantum-to-classical reduction of quantum dynamics is described. The key aspect of our method is the similarity transformation of the Liouvillian, which provides a new perspective. In conventional studies of quantum…

Statistical Mechanics · Physics 2015-04-09 Norikazu Kamiya