On Conservation Laws In Quantum Mechanics, 2021 Chapman University

#### On Conservation Laws In Quantum Mechanics, Yakir Aharonov, Sandu Popescu, Daniel Rohrlich

*Mathematics, Physics, and Computer Science Faculty Articles and Research*

Conservation laws are one of the most important aspects of nature. As such, they have been intensively studied and extensively applied, and are considered to be perfectly well established. We, however, raise fundamental question about the very meaning of conservation laws in quantum mechanics. We argue that, although the standard way in which conservation laws are defined in quantum mechanics is perfectly valid as far as it goes, it misses essential features of nature and has to be revisited and extended.

Shallow-Circuit Variational Quantum Eigensolver Based On Symmetry-Inspired Hilbert Space Partitioning For Quantum Chemical Calculations, 2021 Ames Laboratory

#### Shallow-Circuit Variational Quantum Eigensolver Based On Symmetry-Inspired Hilbert Space Partitioning For Quantum Chemical Calculations, Feng Zhang, Niladri Gomes, Noah F. Berthusen, Peter P. Orth, Cai-Zhuang Wang, Kai-Ming Ho, Yong-Xin Yao

*Physics and Astronomy Publications*

Development of resource-friendly quantum algorithms remains highly desirable for noisy intermediate-scale quantum computing. Based on the variational quantum eigensolver (VQE) with unitary coupled-cluster *Ansatz*, we demonstrate that partitioning of the Hilbert space made possible by the point-group symmetry of the molecular systems greatly reduces the number of variational operators by confining the variational search within a subspace. In addition, we found that instead of including all subterms for each excitation operator, a single-term representation suffices to reach required accuracy for various molecules tested, resulting in an additional shortening of the quantum circuit by a factor of 4–8. With these ...

Understanding The Research And Applications Of Quantum Computing, 2021 The University of Akron

#### Understanding The Research And Applications Of Quantum Computing, Joshua Foss

*Williams Honors College, Honors Research Projects*

In-Depth research of current quantum computing understanding and practices. Presentation of possible new and creative applications of quantum computing.

Quantum Computing For The Quantum Curious, 2021 Illinois Mathematics and Science Academy

#### Quantum Computing For The Quantum Curious, Ciaran Hughes, Joshua Isaacson, Anastasia Perry, Ranbel F. Sun, Jessica Turner

*Open Access Books and Manuals*

This open access book makes quantum computing more accessible than ever before. A fast-growing field at the intersection of physics and computer science, quantum computing promises to have revolutionary capabilities far surpassing “classical” computation. Getting a grip on the science behind the hype can be tough: at its heart lies quantum mechanics, whose enigmatic concepts can be imposing for the novice.

This classroom-tested textbook uses simple language, minimal math, and plenty of examples to explain the three key principles behind quantum computers: superposition, quantum measurement, and entanglement. It then goes on to explain how this quantum world opens up a ...

Equations Of State For Warm Dense Carbon From Quantum Espresso, 2021 Virginia Commonwealth University

#### Equations Of State For Warm Dense Carbon From Quantum Espresso, Derek J. Schauss

*Theses and Dissertations*

Warm dense plasma is the matter that exists, roughly, in the range of 10,000 to 10,000,000 Kelvin and has solid-like densities, typically between 0.1 and 10 grams per centimeter. Warm dense fluids like hydrogen, helium, and carbon are believed to make up the interiors of many planets, white dwarfs, and other stars in our universe. The existence of warm dense matter (WDM) on Earth, however, is very rare, as it can only be created with high-energy sources like a nuclear explosion. In such an event, theoretical and computational models that accurately predict the response of certain ...

Terahertz Second Harmonic Generation Form Nb3sn Superconductor, 2021 Iowa State University and Ames Laboratory

#### Terahertz Second Harmonic Generation Form Nb3sn Superconductor, Dinusha Herath Mudiyanselage

*Creative Components*

Symmetry breaking phenomena in superconductors is a fascinating field of study. Here we report the observation of Terahertz second harmonic generation (T-SHG) from Nb3Sn superconductor. T-SHG can be used as a tool to detect symmetry breaking inside superconducting fluid. Conventionally SHG cannot be observed in superconductors with inversion symmetry. Here we perturb superconducting fluid using Terahertz electromagnetic radiation and break the inversion symmetry to generate T-SHG.

Role Of Boundary Conditions In Quantum Computations Of Scattering Observables, 2021 Old Dominion University

#### Role Of Boundary Conditions In Quantum Computations Of Scattering Observables, Raúl A. Briceño, Juan V. Guerrero, Maxwell T. Hansen, Alexandru M. Sturzu

*Physics Faculty Publications*

Quantum computing may offer the opportunity to simulate strongly interacting field theories, such as quantum chromodynamics, with physical time evolution. This would give access to Minkowski-signature correlators, in contrast to the Euclidean calculations routinely performed at present. However, as with present-day calculations, quantum computation strategies still require the restriction to a finite system size, including a finite, usually periodic, spatial volume. In this work, we investigate the consequences of this in the extraction of hadronic and Compton-like scattering amplitudes. Using the framework presented in Briceno et al. [Phys. Rev. D 101, 014509 (2020)], we estimate the volume effects for various ...

Energy-Dependent Π⁺Π⁺Π⁺ Scattering Amplitude From Qcd, 2021 Old Dominion University

#### Energy-Dependent Π⁺Π⁺Π⁺ Scattering Amplitude From Qcd, Maxwell T. Hansen, Raúl A. Briceño, Robert G. Edwards, Christopher E. Thomas, David J. Wilson

*Physics Faculty Publications*

Focusing on three-pion states with maximal isospin π⁺π⁺π⁺, we present the first nonperturbative determination of an energy-dependent three-hadron scattering amplitude from first-principles QCD. The calculation combines finite-volume three-hadron energies, extracted using numerical lattice QCD, with a relativistic finite-volume formalism, required to interpret the results. To fully implement the latter, we also solve integral equations that relate an intermediate three-body K matrix to the physical three-hadron scattering amplitude. The resulting amplitude shows rich analytic structure and a complicated dependence on the two-pion invariant masses, represented here via Dalitz-like plots of the scattering rate.

Neural-Network Analysis Of Parton Distribution Functions From Ioqffe-Time Pseudodistributions, 2021 Old Dominion University

#### Neural-Network Analysis Of Parton Distribution Functions From Ioqffe-Time Pseudodistributions, Luigi Del Debbio, Tommaso Giani, Joseph Karpie, Kostas Orginos, Anatoly Radyushkin, Savvas Zafeiropoulos

*Physics Faculty Publications*

We extract two nonsinglet nucleon Parton Distribution Functions from lattice QCD data for reduced Ioffe-time pseudodistributions. We perform such analysis within the NNPDF framework, considering data coming from different lattice ensembles and discussing in detail the treatment of the different source of systematics involved in the fit. We introduce a recipe for taking care of systematics and use it to perform our extraction of light-cone PDFs.

Ruling Out Color Transparency In Quasielastic ¹²C(E,E'P) Up To Q² Of 14.2 (Gev/C)², 2021 Old Dominion University

#### Ruling Out Color Transparency In Quasielastic ¹²C(E,E'P) Up To Q² Of 14.2 (Gev/C)², D. Bhetuwal, J. Matter, H. Szumila-Vance, F. Hauenstein, C. Yero, J. Zhang, Et Al., Hall C. Collaboration

*Physics Faculty Publications*

Quasielastic ^{12}C(e,e'p) scattering was measured at spacelike 4-momentum transfer squared Q^{2} = 8, 9.4, 11.4, and 14.2 (GeV/c)^{2}, the highest ever achieved to date. Nuclear transparency for this reaction was extracted by comparing the measured yield to that expected from a plane-wave impulse approximation calculation without any final state interactions. The measured transparency was consistent with no Q^{2} dependence, up to proton momenta of 8.5 GeV/c, ruling out the quantum chromodynamics effect of color transparency at the measured Q^{2} scales in exclusive (e, e'p) reactions. These ...

Photoproduction Of The F₂(1270) Meson Using The Clas Detector, 2021 Old Dominion University

#### Photoproduction Of The F₂(1270) Meson Using The Clas Detector, Krishna P. Adhikari, Moskov J. Amaryan, Dilini Bulumulla, Mohammad Hattawy, G. Gavalian, Charles E. Hyde, Yelena Prok, J. Zhang, Et Al., Clas Collaboration

*Physics Faculty Publications*

The quark structure of the f_{2}(1270) meson has, for many years, been assumed to be a pure quark-antiquark (qq⁻) resonance with quantum numbers J^{PC} = 2^{++}. Recently, it was proposed that the f_{2}(1270) is a molecular state made from the attractive interaction of two 𝜌 mesons. Such a state would be expected to decay strongly to final states with charged pions due to the dominant decay 𝜌 → π^{+}π^{-}, whereas decay to two neutral pions would likely be suppressed. Here, we measure for the first time the reaction 𝛾p -> π^{0}π^{0}p, using the ...

Differential Cross Sections For Λ (1520) Using Photoproduction At Clas, 2021 Old Dominion University

#### Differential Cross Sections For Λ (1520) Using Photoproduction At Clas, K. P. Adhikari, M.J. Amaryan, G. Gavalian, M. Hattawy, Y. Prok, Et. Al., The Clas Collaboration

*Physics Faculty Publications*

The reaction 𝛾p → K+Λ (1520) using photoproduction data from the CLAS g12 experiment at Jefferson Lab is studied. The decay of Λ(1520) into two exclusive channels, Σπ^{+}π^{-} and Σ^{-}π^{+}, is studied from the detected K^{+}, π^{+}, and π^{-} particles. A good agreement is established for the Λ(1520) differential cross sections with the previous CLAS measurements. The differential cross sections as a function of center-of-mass angle are extended to higher photon energies. Newly added are the differential cross sections as a function of invariant four-momentum transfer *t*, which is the natural variable to use for a ...

Measurements Of Dihadron Correlations Relative To The Event Plane In Au Plus Au Collisions At √Snn= 200 Gev, 2021 Old Dominion University

#### Measurements Of Dihadron Correlations Relative To The Event Plane In Au Plus Au Collisions At √Snn= 200 Gev, H. Agakishiev, M. M. Aggarwal, Z. Ahammed, S. Bueltmann, I. Koralt, D. Plyku, Et Al., Star Collaboration

*Physics Faculty Publications*

Dihadron azimuthal correlations containing a high transverse momentum (p_{T}) trigger particle are sensitive to the properties of the nuclear medium created at RHIC through the strong interactions occurring between the traversing parton and the medium, i.e. jet-quenching. Previous measurements revealed a strong modification to dihadron azimuthal correlations in Au+Au collisions with respect to p+p and d+Au collisions. The modification increases with the collision centrality, suggesting a path-length or energy density dependence to the jet-quenching effect. This paper reports STAR measurements of dihadron azimuthal correlations in mid-central (20%-60%) Au+Au collisions at √s_{NN }= 200 ...

Semiclassical Backreaction On Asymptotically Anti–De Sitter Black Holes, 2021 Dublin City University

#### Semiclassical Backreaction On Asymptotically Anti–De Sitter Black Holes, Peter Taylor, Cormac Breen

*Articles*

We consider a quantum scalar field on the classical background of an asymptotically anti–de Sitter black hole and the backreaction the field’s stress-energy tensor induces on the black hole geometry. The backreaction is computed by solving the reduced-order semiclassical Einstein field equations sourced by simple analytical approximations for the renormalized expectation value of the scalar field stress-energy tensor. When the field is massless and conformally coupled, we adopt Page’s approximation to the renormalized stress-energy tensor, while for massive fields we adopt a modified version of the DeWitt-Schwinger approximation. The latter approximation must be modified so that it ...

Quantum Simulation Of The Schrodinger Equation Using Ibm's Quantum Computers, 2020 American University in Cairo

#### Quantum Simulation Of The Schrodinger Equation Using Ibm's Quantum Computers, Mohamed Abouelela

*Capstone and Graduation Projects*

This thesis explores the capabilities of a quantum computer to simulate quantum systems. We give an introduction to the basics of quantum computing with the Bernstein-Vazirani algorithm as a demonstration. Four quantum systems are then simulated using IBM's QASM simulator using 6 qubits: the free particle, eigenstate of an infinite-well, particle in a step potential, and quantum tunneling. Because of the high number of gates, a 6-qubit simulation will not be feasible on current quantum computers. The number of qubits was, thus, reduced to 4 qubits, and was simulated on IBM's 5 qubit quantum computers (ibmq 5 vigo ...

What Is Nonlocal In Counterfactual Quantum Communication?, 2020 Chapman University

#### What Is Nonlocal In Counterfactual Quantum Communication?, Yakir Aharonov, Daniel Rohrlich

*Mathematics, Physics, and Computer Science Faculty Articles and Research*

We revisit the “counterfactual quantum communication” of Salih et al. [1], who claim that an observer “Bob” can send one bit of information to a second observer “Alice” without any physical particle traveling between them. We show that a locally conserved, massless current—specifically, a current of modular angular momentum, Lz mod 2ℏ—carries the one bit of information. We integrate the flux of Lz mod 2ℏ from Bob to Alice and show that it equals one of the two eigenvalues of Lz mod 2ℏ, either 0 or ℏ, thus precisely accounting for the one bit of information he sends ...

An Update On The Computational Theory Of Hamiltonian Period Functions, 2020 University of Arkansas, Fayetteville

#### An Update On The Computational Theory Of Hamiltonian Period Functions, Bradley Joseph Klee

*Theses and Dissertations*

Lately, state-of-the-art calculation in both physics and mathematics has expanded to include the field of symbolic computing. The technical content of this dissertation centers on a few Creative Telescoping algorithms of our own design (Mathematica implementations are given as a supplement). These algorithms automate analysis of integral period functions at a level of difficulty and detail far beyond what is possible using only pencil and paper (unless, perhaps, you happen to have savant-level mental acuity). We can then optimize analysis in classical physics by using the algorithms to calculate Hamiltonian period functions as solutions to ordinary differential equations. The simple ...

Exploring Information For Quantum Machine Learning Models, 2020 University of Louisville

#### Exploring Information For Quantum Machine Learning Models, Michael Telahun

*Electronic Theses and Dissertations*

Quantum computing performs calculations by using physical phenomena and quantum mechanics principles to solve problems. This form of computation theoretically has been shown to provide speed ups to some problems of modern-day processing. With much anticipation the utilization of quantum phenomena in the field of Machine Learning has become apparent. The work here develops models from two software frameworks: TensorFlow Quantum (TFQ) and PennyLane for machine learning purposes. Both developed models utilize an information encoding technique *amplitude encoding* for preparation of states in a quantum learning model. This thesis explores both the capacity for amplitude encoding to provide enriched state ...

Optical Properties Of Ultrathin In(Ga)As/Gaas And In(Ga)N/Gan Quantum Wells, 2020 University of Arkansas, Fayetteville

#### Optical Properties Of Ultrathin In(Ga)As/Gaas And In(Ga)N/Gan Quantum Wells, Yurii Maidaniuk

*Theses and Dissertations*

Recently, structures based on ultrathin quantum wells (QWs) began to play a critical role in modern devices, such as lasers, solar cells, infrared photodetectors, and light-emitting diodes. However, due to the lack of understanding of the formation mechanism of ultrathin QWs during the capping process, scientists and engineers cannot fully explore the potential of such structures. This study aims to investigate how structural parameters of ultrathin QWs affect their emission properties by conducting a systematic analysis of the optical properties of In(Ga)As/GaAs and In(Ga)N/GaN ultrathin QWs. Specifically, the analysis involved photoluminescence measurements combined with ...

Benchmarks And Controls For Optimization With Quantum Annealing, 2020 University of Tennessee, Knoxville

#### Benchmarks And Controls For Optimization With Quantum Annealing, Erica Kelley Grant

*Doctoral Dissertations*

Quantum annealing (QA) is a metaheuristic specialized for solving optimization problems which uses principles of adiabatic quantum computing, namely the adiabatic theorem. Some devices implement QA using quantum mechanical phenomena. These QA devices do not perfectly adhere to the adiabatic theorem because they are subject to thermal and magnetic noise. Thus, QA devices return statistical solutions with some probability of success where this probability is affected by the level of noise of the system. As these devices improve, it is believed that they will become less noisy and more accurate. However, some tuning strategies may further improve that probability of ...