Chemistry as a “Manifestation of Quantum Phenomena” and the Born–Oppenheimer Approximation?

<p>Atomic and molecular properties could be evaluated from the fundamental Schrodinger’s equation and therefore represent different modalities of the same quantum phenomena. Here we present AIMNet, a modular and chemically inspired deep neural network potential. We used AIMNet with multitarget training to learn multiple modalities of the state of the atom in a molecular system. The resulting model shows on several benchmark datasets the state-of-the-art accuracy, comparable to the results of orders of magnitude more expensive DFT methods. It can simultaneously predict several atomic and molecular properties without an increase in computational cost. With AIMNet we show a new dimension of transferability: the ability to learn new targets utilizing multimodal information from previous training. The model can learn implicit solvation energy (like SMD) utilizing only a fraction of original training data, and archive MAD error of 1.1 kcal/mol compared to experimental solvation free energies in MNSol database.</p>

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The Necessity of Sufficiency

10.1093/oso/9780190842215.003.0026 ◽

2018 ◽

Author(s):

Bruce L. Gordon

Keyword(s):

Recent Work ◽

Quantum Physics ◽

Structural Realism ◽

Sufficient Reason ◽

Divine Action ◽

Ontic Structural Realism ◽

Existence Of God ◽

Principle Of Sufficient Reason ◽

Adequate Understanding ◽

Quantum Phenomena

There is an argument for the existence of God from the incompleteness of nature that is vaguely present in Plantinga’s recent work. This argument, which rests on the metaphysical implications of quantum physics and the philosophical deficiency of necessitarian conceptions of physical law, deserves to be given a clear formulation. The goal is to demonstrate, via a suitably articulated principle of sufficient reason, that divine action in an occasionalist mode is needed (and hence God’s existence is required) to bring causal closure to nature and render it ontologically functional. The best explanation for quantum phenomena and the most adequate understanding of general providence turns out to rest on an ontic structural realism in physics that is grounded in the immaterialist metaphysics of theistic idealism.

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Quantum Polaritonic

10.1093/oso/9780198782995.003.0011 ◽

2017 ◽

Author(s):

Alexey V. Kavokin ◽

Jeremy J. Baumberg ◽

Guillaume Malpuech ◽

Fabrice P. Laussy

Keyword(s):

Phase Transitions ◽

Quantum Information ◽

Quantum Information Processing ◽

Quantum Phase Transitions ◽

Macroscopic Quantum ◽

Quantum Simulations ◽

Macroscopic Quantum Phenomena ◽

Microcavity Polaritons ◽

Quantum Phenomena ◽

The One

Microcavity polaritons have demonstrated their unique propensity to host macroscopic quantum phenomena. While they appear to be highly promising for applications in a classical realm, they are still far from competing even with decade old electronics. Another playground where polaritons could emerge as strong contenders is the microscopic quantum regime with single-particle effects and nonlinearities at the one-polariton level. Several theoretical proposals exist to explore polariton blockade mechanisms, realize sophisticated quantum phase transitions, implement quantum simulations and/or quantum information processing, thereby opening a new page of the polariton physics when such ideas will be implemented in the laboratory.

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Introduction

10.1093/oso/9780198805014.003.0001 ◽

2018 ◽

Author(s):

Niels Engholm Henriksen ◽

Flemming Yssing Hansen

Keyword(s):

Schrödinger Equation ◽

Schrodinger Equation ◽

Degrees Of Freedom ◽

State Level ◽

Boltzmann Distribution ◽

Theoretical Description ◽

Time Dependent ◽

Nuclear Dynamics ◽

Molecular Reaction ◽

Oppenheimer Approximation

This introductory chapter considers first the relation between molecular reaction dynamics and the major branches of physical chemistry. The concept of elementary chemical reactions at the quantized state-to-state level is discussed. The theoretical description of these reactions based on the time-dependent Schrödinger equation and the Born–Oppenheimer approximation is introduced and the resulting time-dependent Schrödinger equation describing the nuclear dynamics is discussed. The chapter concludes with a brief discussion of matter at thermal equilibrium, focusing at the Boltzmann distribution. Thus, the Boltzmann distribution for vibrational, rotational, and translational degrees of freedom is discussed and illustrated.

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Full-dimensional quantum stereodynamics of the non-adiabatic quenching of OH(A2Σ+) by H2

Nature Chemistry ◽

10.1038/s41557-021-00730-1 ◽

2021 ◽

Author(s):

Bin Zhao ◽

Shanyu Han ◽

Christopher L. Malbon ◽

Uwe Manthe ◽

David. R. Yarkony ◽

...

Keyword(s):

Quantum Dynamics ◽

Previous Analysis ◽

Branching Ratio ◽

Energy Matrix ◽

Elastic Channel ◽

Electronically Excited ◽

Oppenheimer Approximation ◽

Electronic Motion ◽

Adiabatic Dynamics ◽

Good Agreement

AbstractThe Born–Oppenheimer approximation, assuming separable nuclear and electronic motion, is widely adopted for characterizing chemical reactions in a single electronic state. However, the breakdown of the Born–Oppenheimer approximation is omnipresent in chemistry, and a detailed understanding of the non-adiabatic dynamics is still incomplete. Here we investigate the non-adiabatic quenching of electronically excited OH(A2Σ+) molecules by H2 molecules using full-dimensional quantum dynamics calculations for zero total nuclear angular momentum using a high-quality diabatic-potential-energy matrix. Good agreement with experimental observations is found for the OH(X2Π) ro-vibrational distribution, and the non-adiabatic dynamics are shown to be controlled by stereodynamics, namely the relative orientation of the two reactants. The uncovering of a major (in)elastic channel, neglected in a previous analysis but confirmed by a recent experiment, resolves a long-standing experiment–theory disagreement concerning the branching ratio of the two electronic quenching channels.

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Quantum Physics Literacy Aimed at K12 and the General Public

Universe ◽

10.3390/universe7040086 ◽

2021 ◽

Vol 7 (4) ◽

pp. 86

Author(s):

Caterina Foti ◽

Daria Anttila ◽

Sabrina Maniscalco ◽

Maria Luisa Chiofalo

Keyword(s):

Cultural Change ◽

General Public ◽

Quantum Physics ◽

Physics Teaching ◽

Physics Students ◽

Formidable Challenge ◽

Challenges And Opportunities ◽

Quantum Phenomena ◽

Smart Community ◽

Quantum Science

Educating K12 students and general public in quantum physics represents an evitable must no longer since quantum technologies are going to revolutionize our lives. Quantum literacy is a formidable challenge and an extraordinary opportunity for a massive cultural uplift, where citizens learn how to engender creativity and practice a new way of thinking, essential for smart community building. Scientific thinking hinges on analyzing facts and creating understanding, and it is then formulated with the dense mathematical language for later fact checking. Within classical physics, learners’ intuition may in principle be educated via classroom demonstrations of everyday-life phenomena. Their understanding can even be framed with the mathematics suited to their instruction degree. For quantum physics, on the contrary, we have no experience of quantum phenomena and the required mathematics is beyond non-expert reach. Therefore, educating intuition needs imagination. Without rooting to experiments and some degree of formal framing, educators face the risk to provide only evanescent tales, often misled, while resorting to familiar analogies. Here, we report on the realization of QPlayLearn, an online platform conceived to explicitly address challenges and opportunities of massive quantum literacy. QPlayLearn’s mission is to provide multilevel education on quantum science and technologies to anyone, regardless of age and background. To this aim, innovative interactive tools enhance the learning process effectiveness, fun, and accessibility, while remaining grounded on scientific correctness. Examples are games for basic quantum physics teaching, on-purpose designed animations, and easy-to-understand explanations on terminology and concepts by global experts. As a strategy for massive cultural change, QPlayLearn offers diversified content for different target groups, from primary school all the way to university physics students. It is addressed also to companies wishing to understand the potential of the emergent quantum industry, journalists, and policymakers needing to seize what quantum technologies are about, as well as all quantum science enthusiasts.

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High-Fidelity First Principles Nonadiabaticity: Diabatization, Analytic Representation of Global Diabatic Potential Energy Matrices, and Quantum Dynamics

Physical Chemistry Chemical Physics ◽

10.1039/d1cp03008f ◽

2021 ◽

Author(s):

Yafu Guan ◽

Changjian Xie ◽

David R. Yarkony ◽

Hua Guo

Keyword(s):

Potential Energy ◽

Excited States ◽

First Principles ◽

Quantum Dynamics ◽

Chemical Processes ◽

High Fidelity ◽

Nonadiabatic Dynamics ◽

Electronically Excited States ◽

Electronically Excited ◽

Oppenheimer Approximation

Nonadiabatic dynamics, which goes beyond the Born-Oppenheimer approximation, has increasingly been shown to play an important role in chemical processes, particularly those involving electronically excited states. Understanding multistate dynamics requires...

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