Predictions Of Quantum Mechanics Research Articles

Efficient microwave-assisted synthesis of 1-hexylpyridin-1-ium bromide: Anion exchange to acetate and fundamentals tools to probe its interaction with RuCl3

The study presents a robust and efficient method for synthesizing high-purity 1-hexylpyridin-1-ium acetate (1-HP-Ac), a room-temperature ionic liquid (RTIL), using microwave synthesis. The study also explores its interaction with ruthenium trichloride (RuCl3). Initially, we employed classical solvothermal methods to obtain 1-hexypyridin-1-ium bromide (1-HP-Br), a precursor for 1-HP-Ac. Issues related to impurity and time constraints necessitated a transition to microwave-assisted synthesis, which emerged as an eco-friendly, energy-efficient approach. Microwave synthesis proved superior by delivering shorter reaction times (30 min), higher yields, and eliminating the need for solvents or inert atmospheres. Various characterization techniques (1H NMR, 13C NMR, FTIR, TGA, and HRMS) and matching quantum mechanical NMR predictions confirmed the successful synthesis of the hexylpyridinium cation and anion exchange transforming 1-HP-Br into its acetate form. The interaction between the synthesized RTIL and RuCl3 was monitored through NMR-based titrations and molecular dynamics (MD) modeling. The study explored the effects of increasing amounts of either RTIL or RuCl3 with the critical inflection point at a 1:2 ratio of 1-HP-Ac to RuCl3 for effective interactions and potential changes in average molecular conformation. Specifically, examining Karplus J-coupling constants provided information about dihedral angles within 1-HP-Ac. The data suggested that RuCl3 has a discernible influence on these angles, particularly for aliphatic protons. With thermal stability up to 200 °C, 1-HP-Ac is a fitting candidate for high-temperature reactions. MD simulation quantifies the solvation environment created by the IL as well as elucidates interactions of 1-HP-Ac with the RuCl3 crystal structure. The insights gained from our research into 1-HP-Ac's interaction with RuCl3, combined with the efficiency of microwave-assisted synthesis, open new avenues for further studies in catalysis, material science, and related fields..

Nonlinear nanoresonators for Bell state generation

Entangled photon states are a fundamental resource for optical quantum technologies and investigating the fundamental predictions of quantum mechanics. Up to now such states are mainly generated in macroscopic nonlinear optical systems with elaborately tailored optical properties. In this theoretical work, we extend the understanding on the generation of entangled photonic states toward the nanoscale regime by investigating the fundamental properties of photon-pair generation in sub-wavelength nonlinear nanoresonators. Taking materials with Zinc-Blende structure as an example, we reveal that such systems can naturally generate various polarization-entangled Bell states over a very broad range of wavelengths and emission directions, with little to no engineering needed. Interestingly, we uncover different regimes of operation, where polarization-entangled photons can be generated with dependence on or complete independence from the pumping wavelength and polarization, and the modal content of the nanoresonator. Our work also shows the potential of nonlinear nanoresonators as miniaturized sources of biphoton states with highly complex and tunable properties.

A Macroscopic Quantum Three-Box Paradox: Finding Consistency with Weak Macroscopic Realism.

The quantum three-box paradox considers a ball prepared in a superposition of being in any one of three boxes. Bob makes measurements by opening either box 1 or box 2. After performing some unitary operations (shuffling), Alice can infer with certainty that the ball was detected by Bob, regardless of which box he opened, if she detects the ball after opening box 3. The paradox is that the ball would have been found with certainty by Bob in either box if that box had been opened. Resolutions of the paradox include that Bob's measurement cannot be made non-invasively or else that realism cannot be assumed at the quantum level. Here, we strengthen the case for the former argument by constructing macroscopic versions of the paradox. Macroscopic realism implies that the ball is in one of the boxes prior to Bob or Alice opening any boxes. We demonstrate the consistency of the paradox with macroscopic realism, if carefully defined (as weak macroscopic realism, wMR) to apply to the system at the times prior to Alice or Bob opening any boxes but after the unitary operations associated with preparation or shuffling. By solving for the dynamics of the unitary operations and comparing with mixed states, we demonstrate agreement between the predictions of wMR and quantum mechanics: the paradox only manifests if Alice's shuffling combines both local operations (on box 3) and nonlocal operations, on the other boxes. Following previous work, the macroscopic paradox is shown to correspond to a violation of a Leggett-Garg inequality, which implies failure of non-invasive measurability if wMR holds.

Bell's theorem in time without inequalities

Bell's theorem revealed that a local hidden-variable model cannot completely reproduce the quantum mechanical predictions. Bell's inequality provides an upper bound under the locality and reality assumptions that can be violated by correlated measurement statistics of quantum mechanics. Greenberger, Horne, and Zeilinger (GHZ) gave a more compelling proof of Bell's theorem without inequalities by considering perfect correlations rather than statistical correlations. In this work, we present a temporal analogue of GHZ argument that establishes Bell's theorem in time without inequalities.

Spontaneous Collapse by Entanglement Suppression

AbstractA modified Schrödinger equation having an added nonlinear term, which gives rise to disentanglement, has been recently proposed. The process of quantum measurement is explored for the case of a pair of coupled spins. It is found that the deterministic time evolution generated by the modified Schrödinger equation mimics the process of wavefunction collapse. Added noise gives rise to stochasticity in the measurement process. Conflict with both principles of causality and separability can be avoided by postulating that the nonlinear term is active only during the time when subsystems interact. Moreover, in the absence of entanglement, all predictions of standard quantum mechanics are unaffected by the added nonlinear term.

The GHZ Theorem Revisited within the Framework of Gauge Theory

The Greenberger-Horne-Zeilinger version of the Einstein-Podolsky-Rosen (EPR) paradox is widely regarded as a conclusive logical argument that rules out the possibility of reproducing the predictions of Quantum Mechanics within the framework of any physical theory sharing the notions of reality and relativistic causality that we acknowledge as a given in our classical descriptions of the macroscopic world. Thus, this renowned argument stands as a seemingly insurmountable roadblock on the path to a very desired, physically intuitive understanding of quantum phenomena and, in particular, quantum entanglement. In this paper, we notice, however, that the GHZ argument involves unaccounted spurious gauge degrees of freedom and that it can be overcome once these degrees are properly taken into account. It is then possible to explicitly build a successful statistical model for the GHZ experiment based on the usual notions of relativistic causality and physical reality. This model, thus, completes—in the EPR sense—the quantum description of the GHZ state and paves the way to a novel intuitive interpretation of the quantum formalism and a deeper understanding of the physical reality that it describes.

Thermodynamics and its prediction and CALPHAD modeling: Review, state of the art, and perspectives

Thermodynamics is a science concerning the state of a system, whether it is stable, metastable, or unstable, when interacting with its surroundings. The combined law of thermodynamics derived by Gibbs about 150 years ago laid the foundation of thermodynamics. In Gibbs combined law, the entropy production due to internal processes was not included, and the 2nd law was thus practically removed from the Gibbs combined law, so it is only applicable to systems under equilibrium, thus commonly termed as equilibrium or Gibbs thermodynamics. Gibbs further derived the classical statistical thermodynamics in terms of the probability of configurations in a system in the later 1800's and early 1900's. With the quantum mechanics (QM) developed in 1920's, the QM-based statistical thermodynamics was established and connected to classical statistical thermodynamics at the classical limit as shown by Landau in the 1940's. In 1960's the development of density functional theory (DFT) by Kohn and co-workers enabled the QM prediction of properties of the ground state of a system. On the other hand, the entropy production due to internal processes in non-equilibrium systems was studied separately by Onsager in 1930's and Prigogine and co-workers in the 1950's. In 1960's to 1970's the digitization of thermodynamics was developed by Kaufman in the framework of the CALculation of PHAse Diagrams (CALPHAD) modeling of individual phases with internal degrees of freedom. CALPHAD modeling of thermodynamics and atomic transport properties has enabled computational design of complex materials in the last 50 years. Our recently termed zentropy theory integrates DFT and statistical mechanics through the replacement of the internal energy of each individual configuration by its DFT-predicted free energy. The zentropy theory is capable of accurately predicting the free energy of individual phases, transition temperatures and properties of magnetic and ferroelectric materials with free energies of individual configurations solely from DFT-based calculations and without fitting parameters, and is being tested for other phenomena including superconductivity, quantum criticality, and black holes. Those predictions include the singularity at critical points with divergence of physical properties, negative thermal expansion, and the strongly correlated physics. Those individual configurations may thus be considered as the genomic building blocks of individual phases in the spirit of the materials genome®. This has the potential to shift the paradigm of CALPHAD modeling from being heavily dependent on experimental inputs to becoming fully predictive with inputs solely from DFT-based calculations and machine learning models built on those calculations and existing experimental data through newly developed and future open-source tools. Furthermore, through the combined law of thermodynamics including the internal entropy production, it is shown that the kinetic coefficient matrix of independent internal processes is diagonal with respect to the conjugate potentials in the combined law, and the cross phenomena that the phenomenological Onsager flux and reciprocal relationships are due to the dependence of the conjugate potential of a molar quantity on nonconjugate molar quantities and other potentials, which can be predicted by the zentropy theory and CALPHAD modeling.

How Everett Solved the Probability Problem in Everettian Quantum Mechanics

A longstanding issue in the Everettian (Many-Worlds) interpretation is to justify and make sense of the Born rule that underlies the statistical predictions of standard quantum mechanics. The paper offers a reappraisal of Everett’s original account in light of the recent literature on the concept of typicality. It argues that Everett’s derivation of the Born rule is sound and, in a certain sense, even an optimal result, and defends it against the charge of circularity. The conclusion is that Everett’s typicality argument can successfully ground post-factum explanations of Born statistics, while questions remain about the predictive power of the Many-Worlds interpretation.

Quantum Mechanical Prediction and Experimental Verification of Au(I)-Catalyzed Substitution-Controlled Syntheses of 1H-Pyrido[4,3-b]indole and Spiro[indoline-3,3'-pyridine] Derivatives.

Density functional theory calculations were applied to predict the pathways of gold(I)-catalyzed cycloisomerization of the indole substrates with 1,6-enynes, which were consistent with the ensuing experimental results. The substitution-controlled synthesis led to the formation of 1H-pyrido[4,3-b]indole and spiro[indoline-3,3'-pyridine] derivatives in a tunable way. The reactions had good functional group tolerances, and a possible mechanism was proposed based on the computational and experimental results.

Do We Have any Viable Solution to the Measurement Problem?

Wallace (2022) has recently argued that a number of popular approaches to the measurement problem can't be fully extended to relativistic quantum mechanics and quantum field theory; Wallace thus contends that as things currently stand, only the unitary-only approaches to the measurement problem are viable. However, the unitary-only approaches face serious epistemic problems which may threaten their viability as solutions, and thus we consider that it remains an urgent outstanding problem to find a viable solution to the measurement problem which can be extended to relativistic quantum mechanics. In this article we seek to understand in general terms what such a thing might look like. We argue that in order to avoid serious epistemic problems, the solution must be a single-world realist approach, and we further argue that any single-world realist approach which is able to reproduce the predictions of relativistic quantum mechanics will most likely have the property that our observable reality does not supervene on dynamical, precisely-defined microscopic beables. Thus we suggest three possible routes for further exploration: observable reality could be approximate and emergent, as in relational quantum mechanics with the addition of cross-perspective links, or observable reality could supervene on beables which are not microscopically defined, as in the consistent histories approach, or observable reality could supervene on beables which are not dynamical, as in Kent's solution to the Lorentzian classical reality problem. We conclude that once all of these issues are taken into account, the options for a viable solution to the measurement problem are significantly narrowed down.

SIMULATING THE DYNAMICS OF A PARTICLE IN A QUANTUM MECHANICAL OSCILLATOR: A MULTIDIMENSIONAL WAVE FUNCTION APPROACH

This research paper presents a simulation of a particle in a quantum mechanical oscillator, modeled as a multidimensional wave function. The simulation was created by solving the time-dependent Schrodinger equation, which was discretized in both the spatial and time domains, and then approximated using a finite difference method. The objective of this research was to gain a deeper understanding of the behavior of a particle in a quantum mechanical oscillator and to provide visualizations and calculations of relevant physical observables. Initial conditions for the wave function, such as a Gaussian wave packet, were chosen and parameters for the simulation, such as the spatial step size and total simulation time, were set. The results of the simulation showed the evolution of the wave function over time, providing a clear picture of the particles behavior within the potential well of the oscillator. Additionally, physical observables, such as the average position, average kinetic energy, and average potential energy, were calculated and used to validate the simulation and the predictions of quantum mechanics. In conclusion, this research provides a comprehensive understanding of the behavior of a particle in a quantum mechanical oscillator and highlights the importance of simulations in advancing our knowledge of quantum mechanics. The results of this research can contribute to various fields, such as quantum computation and quantum control, and have the potential to drive further breakthroughs in these fields. KEYWORDS: Quantum mechanical oscillator, particle behavior, multidimensional wave function, Schrödinger equation, finite difference method, physical observables, simulation, quantum mechanics, quantum computation, quantum control.

Empirical Validation of “G-D’s Physics’” “UNCIARE Critical Prediction” Discards “Dark-Matter” as “Superfluous”!

Despite numerous experimental efforts to “detect” the presence of “Dark-Matter” (DM) over the past two decade (assumed to comprise up to 95% of all the mass in the universe), no direct experimental evidence of DM has been found to date. But, without the existence of “dark-matter” the accelerated rate of the universe’s expansion cannot be explained? Fortunately, a new alternative “G-D’s Physics” (previously termed: the “Computational Unified Field Theory”) was discovered that offers an alternative explanation for the accelerated expansion of the universe – while discarding “dark-matter” as “superfluous” (i.e., non-existent”). Based on direct empirical validation of two unique “Critical Predictions” of the “G-D’s Physics”, as more valid than the corresponding predictions of both General Relativity Theory (GRT) and Quantum Mechanics (QM) the” G-D’s Physics” is accepted as the new satisfactory Physics Paradigm for 21st century Theoretical Physics; Specifically, empirical validation of the “G-D’s Physics” “Universe’s Non-Continuous Increase in its Accelerated Rate of Expansion (UNCIARE) “Critical Prediction” as evidenced by the “Astronomical-Cosmological Gap in the Universe’s Accelerated Rate of Expansion” (ACGUARE) negates the possibility of the existence of “dark-matter”. The (purely hypothetical) existence of DM is further negated based on the G-D’s Physics “Computational Duality Principle” Theoretical Postulate, which points at the G-D’s Physics singular higher-ordered “Universal Computational Principle” (UCP) that simultaneously computes every exhaustive spatial pixel in the universe at the incredible rate of “c2/h” = 1.36-50 (sec’)! The new G-D’s Physics Paradigm is also shown to resolve the apparent “theoretical inconsistency” between GRT & QM and completely unify between the four basic physical features of “space”,” time”, “energy” & “mass”, based on a newly discovered “Universal Computational Formula” (UCP).

Bypassing the Kochen–Specker Theorem: An Explicit Non-Contextual Statistical Model for the Qutrit

We describe an explicitly non-contextual statistical model of hidden variables for the qutrit, which fully reproduces the predictions of quantum mechanics, and thus, bypasses the constraints imposed by the Kochen–Specker theorem and its subsequent reformulations. We notice that these renowned theorems crucially rely on the implicitly assumed existence of an absolute frame of reference with respect to which physically indistinguishable tests related by spurious gauge transformations can supposedly be assigned well-defined distinct identities. We observe that the existence of such an absolute frame of reference is not required by fundamental physical principles, and hence, assuming it is an unnecessarily restrictive demand.

Precision measurements of the 12C(αγ) reaction with gamma beams and TPC detector(s)

The cross section of the 12C(α,γ)16O reaction, well-recognized as the most important nuclear input of stellar evolution theory, has eluded precise measurements over the last few decades, as evident in the lack of precise confirmation of an elementary prediction of quantum mechanics of the E1-E2 mixing phase angle (ϕ12). More troubling are modern data, measured with 4π array of HPGe detectors, that are in conflict with this prediction. A new method to measure this cross section with TPC detectors and gamma-beams, by measuring the time reverse 16O(γ,α)12C reaction discussed here, shows great promise, for example the measured data do not disagree with the predicted π12 and agree with the predicted trend.

The Bell inequalities: Commentary on the Nobel Prize in Physics 2022

<p indent="0mm">The Nobel Prize in Physics 2022 was awarded to three experiment physicists: Alain Aspect, John F. Clauser and Anton Zeilinger, for their contributions to “experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science”. In this paper, the history, basics, and applications related with the Bell inequalities are reviewed. The discussion of fundamental issues on quantum mechanics dated back to the year 1927 when the fifth Solvay conference was held, highlighting intense arguments between Albert Einstein and Niels Bohr. At the time, Einstein expressed, publicly for the first time, his critical attitude towards quantum mechanics. While the arguments did not reach a decisive conclusion, Bohr’s probabilistic interpretation of quantum mechanics, the Copenhagen interpretation, had since been well circulated among the community. Einstein’s arguments with Bohr lasted many years after the conference. The arguably most famous one was the Einstein-Podolsky-Rosen (EPR) paradox, proposed in a 1935 paper written by the three authors. They stated, by flawless reasoning, that quantum mechanics is ‘incomplete’. Bohr replied immediately. So did Erwin Schrödinger, who, in particular, coined the term ‘entangled’ for the first time to describe the bizarre quantum mechanical property. Nevertheless, the EPR paper received few citations at its publication, until 1990’s when quantum information science started blossoming. From today’s perspective, the paper resembles the ‘sleeping beauty’ who slumbered for decades before fully awakening. It has been widely accepted that it was John S. Bell who eventually resolved the EPR paradox. But many important figures before him should not go unnoticed, including John A. Wheeler, Chien-Shiung Wu, David Bohm, to name a few. In 1964, Bell wrote down a mathematical inequality which satisfies local hidden variable theory but which can be violated in quantum mechanics. The significance is that Bell’s inequality brings the rather philosophic debates on the EPR paradox down to be experimentally testable. Hence, an experiment is here appealing, as is the case in all fields of physics. To the end, John F. Clauser, alongside Stuart J. Freedman, conducted an experiment in 1972 to test a Bell inequality, the Bell-Clauser-Horne-Shimony-Holt (CHSH) inequality, proposed by him and his collaborators in 1969. The results, however, leaves loopholes open. One of the loopholes was closed in a later experiment led by Alain Aspect in 1982. The Bell-CHSH inequality was later tested under a much stricter condition by Anton Zeilinger’s team. Two most important loopholes were both closed by three teams in 2015 independently. Zeilinger’s team was among them. Almost all experiments to date have confirmed quantum mechanical predictions. Zeilinger’s team also performed the first teleportation of unknown quantum states, the first entanglement swapping, along with other contributions pioneering the quantum information science. In retrospect, the foundational study of quantum theory has been developed over a century. It once drew much of quantum physics founders’ attention, went virtually unnoticed while other physical fields advanced, had for quite a while been considered to have very weak relationship with major physics, and finally revived in recent decades leading to rapid progress in quantum information science and quantum technology. We believe that the Nobel Prize in Physics this year is not only an award and recognition to past achievements, but also heralds a new era of science in future.

Phosphine Modulation for Enhanced CO2 Capture: Quantum Mechanics Predictions of New Materials.

It is imperative to develop efficient CO2 capture and activation technologies to combat the rising levels of deleterious greenhouse gases in the atmosphere. Using Quantum Mechanics methods (Density Functional Theory), we propose and evaluate several metal-free and metal-containing phosphines that provide strong CO2 binding under ambient conditions. Depending on the electron donating capacity of the phosphine and the ability of the P-bound ligands to hydrogen bond to the CO2, we find that the CO2 binding can be as strong as -18.6 kcal/mol downhill, which should be quite adequate for ambient conditions. We explore some modifications of the phosphine to improve CO2 binding, and we elucidate which chemical descriptors correlate directly with CO2 binding energy. Specifically, we find that charge accumulation on the CO2 unit of the CO2-bound adduct has the greatest correlation with CO2 binding affinity. Finally, we probe the mechanism for CO2 reduction to CO and methanol in aqueous media.

The Point of Primitive Ontology

Bohmian mechanics grounds the predictions of quantum mechanics in precise dynamical laws for a primitive ontology of point particles. In an appraisal of the de-Broglie-Bohm theory, the paper discusses the crucial epistemological and conceptual role that a primitive ontology plays within a physical theory. It argues that quantum theories without primitive ontology fail to make contact with observable reality in a clear and consistent manner. Finally, it discusses Einstein's epistemological model and why it supports the primitive ontology approach.

Perturbative Quantum Simulation.

Approximation based on perturbation theory is the foundation for most of the quantitative predictions of quantum mechanics, whether in quantum many-body physics, chemistry, quantum field theory, or other domains. Quantum computing provides an alternative to the perturbation paradigm, yet state-of-the-art quantum processors with tens of noisy qubits are of limited practical utility. Here, we introduce perturbative quantum simulation, which combines the complementary strengths of the two approaches, enabling the solution of large practical quantum problems using limited noisy intermediate-scale quantum hardware. The use of a quantum processor eliminates the need to identify a solvable unperturbed Hamiltonian, while the introduction of perturbative coupling permits the quantum processor to simulate systems larger than the available number of physical qubits. We present an explicit perturbative expansion that mimics the Dyson series expansion and involves only local unitary operations, and show its optimality over other expansions under certain conditions. We numerically benchmark the method for interacting bosons, fermions, and quantum spins in different topologies, and study different physical phenomena, such as information propagation, charge-spin separation, and magnetism, on systems of up to 48 qubits only using an 8+1 qubit quantum hardware. We demonstrate our scheme on the IBM quantum cloud, verifying its noise robustness and illustrating its potential for benchmarking large quantum processors with smaller ones.

Improving the Brightness of Pyronin Fluorophore Systems through Quantum-Mechanical Predictions.

The pyronin class of fluorophores serves a critical role in numerous imaging applications, particularly involving preferential staining of RNA through base pair intercalation. Despite this important role in molecular staining applications, the same set of century-old pyronins (i.e., pyronin Y (PY) and pyronin B (PB)), which possess relatively low fluorophore brightness, are still predominantly being used due to the lack of methodology for generating enhanced variants. Here, we use TD-DFT calculations of interconversion energies between structures on the S1 surface as a preliminary means to evaluate fluorophore brightness for a proposed set of pyronins containing variable substitution patterns at the 2, 3, 6, and 7 positions. Using a nucleophilic aromatic substitution/hydride addition approach, we synthesized the same set of pyronins and demonstrate that quantum-mechanical computations are useful for predicting fluorophore performance. We produced the brightest series of pyronin fluorophores described to date, which possess considerable gains over PY and PB.

A quantum mechanical prediction of C24 fullerene as a DNA nucleobase biosensor

We aim to study the interaction of different nucleobases (adenine (A), thymine (T), guanine (G), cytosine (C) and uracil (U)) with the C24 fullerene (D6d symmetry) and to get the binding sequence of these nucleobases using dispersion (D3) corrected density functional theory (DFT). To evaluate the interaction between the nucleobases with the C24 fullerene, we have performed adsorption energy calculation, NBO analysis, Mulliken charge analysis, density of state calculation, sensing response analysis and recovery time calculation. We observed that adsorption sequence of nucleobase follows the trend as A > C > G > T > U. Due to interaction between the nucleobases and C24 fullerene charge redistribution takes place between them and induces the dipole moment. Adenine can be enisled from the other DNA nucleobase molecules, while cytosine and guanine can be sensed with the recovery time of 10−14 s in gas phase. The interaction energy increases for adenine and cytosine with solvent effect confirms their application as carrier.