Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Quantum Physics (29)
- Condensed Matter Physics (23)
- Atomic, Molecular and Optical Physics (11)
- Mathematics (9)
- Other Mathematics (8)
-
- Arts and Humanities (7)
- Philosophy (6)
- Philosophy of Science (5)
- Algebra (3)
- Elementary Particles and Fields and String Theory (3)
- Engineering (3)
- Other Philosophy (3)
- Applied Mathematics (2)
- Electrical and Computer Engineering (2)
- Geometry and Topology (2)
- Optics (2)
- Plasma and Beam Physics (2)
- Algebraic Geometry (1)
- Analysis (1)
- Animal Sciences (1)
- Aquaculture and Fisheries (1)
- Artificial Intelligence and Robotics (1)
- Astrophysics and Astronomy (1)
- Computer Sciences (1)
- Dynamic Systems (1)
- Dynamical Systems (1)
- Earth Sciences (1)
- Keyword
-
- Quantum physics (6)
- Book reviews (4)
- Superconductivity (4)
- Optical fibers (3)
- Stimulated Brillouin scattering (3)
-
- Antenna arrays (2)
- Critical temperature (2)
- Crystal structure (2)
- Detectors (2)
- Faraday rotator (2)
- Lattice parameters (2)
- Magnetoresistance (2)
- Quantum mechanics (2)
- Radar (2)
- Slow light (2)
- Spin angular momentum (2)
- Superconducting devices (2)
- Superconducting films (2)
- Weak values (2)
- Ab-initio calculations (1)
- Acoustic fields (1)
- Acoustic levitation (1)
- Adaptive photonics (1)
- Apatites (1)
- Approximating sequence (1)
- Atomic (1)
- Beltrami equation (1)
- Chiral states (1)
- Classical physics (1)
- Clifford algebra (1)
- Publication Year
- Publication
-
- Mathematics, Physics, and Computer Science Faculty Articles and Research (65)
- Philosophy Faculty Articles and Research (5)
- Engineering Faculty Articles and Research (2)
- Biology, Chemistry, and Environmental Sciences Faculty Articles and Research (1)
- Computational and Data Sciences (PhD) Dissertations (1)
- Publication Type
Articles 31 - 60 of 78
Full-Text Articles in Other Physics
Benchmarks Of Nonclassicality For Qubit Arrays, Mordecai Waegell, Justin Dressel
Benchmarks Of Nonclassicality For Qubit Arrays, Mordecai Waegell, Justin Dressel
Mathematics, Physics, and Computer Science Faculty Articles and Research
We present a set of practical benchmarks for N-qubit arrays that economically test the fidelity of achieving multi-qubit nonclassicality. The benchmarks are measurable correlators similar to two-qubit Bell correlators, and are derived from a particular set of geometric structures from the N-qubit Pauli group. These structures prove the Greenberger–Horne–Zeilinger (GHZ) theorem, while the derived correlators witness genuine N-partite entanglement and establish a tight lower bound on the fidelity of particular stabilizer state preparations. The correlators need only M ≤ N + 1 distinct measurement settings, as opposed to the 22N − 1 settings that would normally be …
A Panorama On Superoscillations, Fabrizio Colombo, Irene Sabadini, Daniele Carlo Struppa
A Panorama On Superoscillations, Fabrizio Colombo, Irene Sabadini, Daniele Carlo Struppa
Mathematics, Physics, and Computer Science Faculty Articles and Research
Purpose of this note is to give an overview on superoscillating sequences and some of their properties. We discuss their persistence in time under Schrödinger equation, we propose various classes of superoscillating functions and we also briefly mention how they can be used to approximate some generalized functions.
Out-Of-Time-Ordered-Correlator Quasiprobabilities Robustly Witness Scrambling, José Raúl González Alonso, Nicole Yunger Halpern, Justin Dressel
Out-Of-Time-Ordered-Correlator Quasiprobabilities Robustly Witness Scrambling, José Raúl González Alonso, Nicole Yunger Halpern, Justin Dressel
Mathematics, Physics, and Computer Science Faculty Articles and Research
Out-of-time-ordered correlators (OTOCs) have received considerable recent attention as qualitative witnesses of information scrambling in many-body quantum systems. Theoretical discussions of OTOCs typically focus on closed systems, raising the question of their suitability as scrambling witnesses in realistic open systems. We demonstrate empirically that the nonclassical negativity of the quasiprobability distribution (QPD) behind the OTOC is a more sensitive witness for scrambling than the OTOC itself. Nonclassical features of the QPD evolve with timescales that are robust with respect to decoherence and are immune to false positives caused by decoherence. To reach this conclusion, we numerically simulate spinchain dynamics and …
Why Physical Understanding Should Precede The Mathematical Formalism—Conditional Quantum Probabilities As A Case-Study, Yakir Aharonov, Eliahu Cohen, David H. Oaknin
Why Physical Understanding Should Precede The Mathematical Formalism—Conditional Quantum Probabilities As A Case-Study, Yakir Aharonov, Eliahu Cohen, David H. Oaknin
Mathematics, Physics, and Computer Science Faculty Articles and Research
Conditional probabilities in quantum systems which have both initial and final boundary conditions are commonly evaluated using the Aharonov–Bergmann–Lebowitz rule. In this short note, we present a seemingly disturbing paradox that appears when applying the rule to systems with slightly broken degeneracies. In these cases, we encounter a singular limit—the probability “jumps” when going from perfect degeneracy to negligibly broken one. We trace the origin of the paradox and solve it from both traditional and modern perspectives in order to highlight the physics behind it: the necessity to take into account the finite resolution of the measuring device. As a …
Completely Top–Down Hierarchical Structure In Quantum Mechanics, Yakir Aharonov, Eliahu Cohen, Jeff Tollaksen
Completely Top–Down Hierarchical Structure In Quantum Mechanics, Yakir Aharonov, Eliahu Cohen, Jeff Tollaksen
Mathematics, Physics, and Computer Science Faculty Articles and Research
Can a large system be fully characterized using its subsystems via inductive reasoning? Is it possible to completely reduce the behavior of a complex system to the behavior of its simplest “atoms”? In this paper we answer these questions in the negative for a specific class of systems and measurements. After a general introduction of the topic, we present the main idea with a simple two-particle example, where strong correlations arise between two apparently empty boxes. This leads to surprising effects within atomic and electromagnetic systems. A general construction based on preand postselected ensembles is then suggested, wherein the Nbody …
Locality And Nonlocality In The Interaction-Free Measurement, Daniel Rohrlich, Yakir Aharonov, Tomer Landsberger
Locality And Nonlocality In The Interaction-Free Measurement, Daniel Rohrlich, Yakir Aharonov, Tomer Landsberger
Mathematics, Physics, and Computer Science Faculty Articles and Research
We present a paradox involving a particle and a mirror. They exchange a nonlocal quantity, modular angular momentum Lz mod 2ћ, but there seems to be no local interaction between them that allows such an exchange. We demonstrate that the particle and mirror do interact locally via a weak local current 〈Lz mod 2ћ〉w. In this sense, we transform the “interaction-free measurement” of Elitzur and Vaidman, in which two local quantities (the positions of a photon and a bomb in the two arms of a Mach-Zehnder interferometer) interact nonlocally, into a thought experiment in which two …
Generalized Fock Spaces And The Stirling Numbers, Daniel Alpay, Motke Porat
Generalized Fock Spaces And The Stirling Numbers, Daniel Alpay, Motke Porat
Mathematics, Physics, and Computer Science Faculty Articles and Research
The Bargmann-Fock-Segal space plays an important role in mathematical physics and has been extended into a number of directions. In the present paper, we imbed this space into a Gelfand triple. The spaces forming the Fréchet part (i.e., the space of test functions) of the triple are characterized both in a geometric way and in terms of the adjoint of multiplication by the complex variable, using the Stirling numbers of the second kind. The dual of the space of test functions has a topological algebra structure, of the kind introduced and studied by the first named author and Salomon.
Weak Values From Strong Interactions In Neutron Interferometry, Tobias Denkmayr, Justin Dressel, Hermann Geppert-Kleinrath, Yuji Hasegawa, Stephan Sponar
Weak Values From Strong Interactions In Neutron Interferometry, Tobias Denkmayr, Justin Dressel, Hermann Geppert-Kleinrath, Yuji Hasegawa, Stephan Sponar
Mathematics, Physics, and Computer Science Faculty Articles and Research
In their original framework weak values must be measured by weak measurements that are minimally disturbing, meaning that the coupling between an investigated quantum system and a measurement device has no influence on the evolution of the system. However, under certain circumstances this weakness of the interaction is not necessary. In that case weak values can still be exactly determined from the statistics of the outcomes of arbitrary-strength generalized measurements. Here, we report an experimental procedure for neutron matter-waves that extends the notion of generalized eigenvalues for the neutron’s path system to allow the exact determination of weak values using …
Quasiprobability Behind The Out-Of-Time-Ordered Correlator, Nicole Yunger Halpern, Brian Swingle, Justin Dressel
Quasiprobability Behind The Out-Of-Time-Ordered Correlator, Nicole Yunger Halpern, Brian Swingle, Justin Dressel
Mathematics, Physics, and Computer Science Faculty Articles and Research
Two topics, evolving rapidly in separate fields, were combined recently: the out-of-time-ordered correlator (OTOC) signals quantum-information scrambling in many-body systems. The Kirkwood-Dirac (KD) quasiprobability represents operators in quantum optics. The OTOC was shown to equal a moment of a summed quasiprobability [Yunger Halpern, Phys. Rev. A 95, 012120 (2017)]. That quasiprobability, we argue, is an extension of the KD distribution. We explore the quasiprobability's structure from experimental, numerical, and theoretical perspectives. First, we simplify and analyze Yunger Halpern's weak-measurement and interference protocols for measuring the OTOC and its quasiprobability. We decrease, exponentially in system size, the number of trials …
Weak-Value Amplification And Optimal Parameter Estimation In The Presence Of Correlated Noise, Josiah Sinclair, Matin Hallaji, Aephraim M. Steinberg, Jeff Tollaksen, Andrew N. Jordan
Weak-Value Amplification And Optimal Parameter Estimation In The Presence Of Correlated Noise, Josiah Sinclair, Matin Hallaji, Aephraim M. Steinberg, Jeff Tollaksen, Andrew N. Jordan
Mathematics, Physics, and Computer Science Faculty Articles and Research
We analytically and numerically investigate the performance of weak-value amplification (WVA) and related parameter estimation methods in the presence of temporally correlated noise. WVA is a special instance of a general measurement strategy that involves sorting data into separate subsets based on the outcome of a second “partitioning” measurement. Using a simplified correlated noise model that can be analyzed exactly together with optimal statistical estimators, we compare WVA to a conventional measurement method. We find that WVA indeed yields a much lower variance of the parameter of interest than the conventional technique does, optimized in the absence of any partitioning …
Evolution Of Superoscillations For Schrödinger Equation In A Uniform Magnetic Field, Fabrizio Colombo, Jonathan Gantner, Daniele C. Struppa
Evolution Of Superoscillations For Schrödinger Equation In A Uniform Magnetic Field, Fabrizio Colombo, Jonathan Gantner, Daniele C. Struppa
Mathematics, Physics, and Computer Science Faculty Articles and Research
Aharonov-Berry superoscillations are band-limited functions that oscillate faster than their fastest Fourier component. Superoscillations appear in several fields of science and technology, such as Aharonov’s weak measurement in quantum mechanics, in optics, and in signal processing. An important issue is the study of the evolution of superoscillations using the Schrödinger equation when the initial datum is a weak value. Some superoscillatory functions are not square integrable, but they are real analytic functions that can be extended to entire holomorphic functions. This fact leads to the study of the continuity of a class of convolution operators acting on suitable spaces of …
On A Class Of Quaternionic Positive Definite Functions And Their Derivatives, Daniel Alpay, Fabrizio Colombo, Irene Sabadini
On A Class Of Quaternionic Positive Definite Functions And Their Derivatives, Daniel Alpay, Fabrizio Colombo, Irene Sabadini
Mathematics, Physics, and Computer Science Faculty Articles and Research
In this paper, we start the study of stochastic processes over the skew field of quaternions. We discuss the relation between positive definite functions and the covariance of centered Gaussian processes and the construction of stochastic processes and their derivatives. The use of perfect spaces and strong algebras and the notion of Fock space are crucial in this framework.
Saving The Physics Ii: Who Needs To Be Saved? It Depends On Your Metaphysics, Menas Kafatos
Saving The Physics Ii: Who Needs To Be Saved? It Depends On Your Metaphysics, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
Physics does not need to be saved. If anything, physics was rescued in the early twentieth century with the advancement of both the theories of relativity and quantum mechanics. What needs to be saved is our world outlook or metaphysics because how a society acts and develops depends on what its belief systems are. Here we explore how a new metaphysics where consciousness is fundamental might just be what modern societies need.
Review Of Qbism: The Future Of Quantum Physics, Matthew S. Leifer
Review Of Qbism: The Future Of Quantum Physics, Matthew S. Leifer
Mathematics, Physics, and Computer Science Faculty Articles and Research
A review of QBism: The Future of Quantum Physics by Hans Christian von Baeyer.
Tests For Intrinsicness Tested, Kelvin J. Mcqueen, René Van Woudenberg
Tests For Intrinsicness Tested, Kelvin J. Mcqueen, René Van Woudenberg
Philosophy Faculty Articles and Research
Various tests have been proposed as helps to identify intrinsic properties. This paper compares three prominent tests (we call them Perfect Duplication, Real Change, and Lonely) and shows that they fail to pass adequate verdicts on a set of three properties. The paper examines whether improved versions of the tests can reduce or remove these negative outcomes. We reach the sceptical conclusion that whereas some of the tests must be discarded as inadequate because they don’t yield definite results, the remaining tests depend for their application on the details of fundamental particle physics so much so that they cannot be …
Superconducting Antenna Concept For Gravitational Waves, Armen Gulian, J Foreman, Vahan Nikoghosyan, Shmuel Nussinov, Louis Sica, Jeff Tollaksen
Superconducting Antenna Concept For Gravitational Waves, Armen Gulian, J Foreman, Vahan Nikoghosyan, Shmuel Nussinov, Louis Sica, Jeff Tollaksen
Mathematics, Physics, and Computer Science Faculty Articles and Research
The most advanced contemporary efforts and concepts for registering gravitational waves are focused on measuring tiny deviations in large arm (kilometers in case of LIGO and thousands of kilometers in case of LISA) interferometers via photons. In this report we discuss a concept for the detection of gravitational waves using an antenna comprised of superconducting electrons (Cooper pairs) moving in an ionic lattice. The major challenge in this approach is that the tidal action of the gravitational waves is extremely weak compared with electromagnetic forces. Any motion caused by gravitational waves, which violates charge neutrality, will be impeded by Coulomb …
Current-Biased Transition-Edge Sensors Based On Re-Entrant Superconductors, Armen Gulian, Vahan Nikoghosyan, Jeff Tollaksen, V. Vardanyan, A. Kuzanyan
Current-Biased Transition-Edge Sensors Based On Re-Entrant Superconductors, Armen Gulian, Vahan Nikoghosyan, Jeff Tollaksen, V. Vardanyan, A. Kuzanyan
Mathematics, Physics, and Computer Science Faculty Articles and Research
Transition-edge sensors are widely recognized as one of the most sensitive tools for the photon and particles detection in many areas, from astrophysics to quantum computing. Their application became practical after understanding that rather than being biased in a constant current mode, they should be biased in a constant voltage mode. Despite the methods of voltage biasing of these sensors are well developed since then, generally the current biasing is more convenient for superconducting circuits. Thus transition-edge sensors designed inherently to operate in the current-biased mode are desirable. We developed a design for such detectors based on re-entrant superconductivity. In …
Engineering Room-Temperature Superconductors Via Ab-Initio Calculations, Mamikon Gulian, Gurgen Melkonyan, Armen Gulian
Engineering Room-Temperature Superconductors Via Ab-Initio Calculations, Mamikon Gulian, Gurgen Melkonyan, Armen Gulian
Mathematics, Physics, and Computer Science Faculty Articles and Research
The BCS, or bosonic model of superconductivity, as Little and Ginzburg have first argued, can bring in superconductivity at room temperatures in the case of high-enough frequency of bosonic mode. It was further elucidated by Kirzhnits et al., that the condition for existence of high-temperature superconductivity is closely related to negative values of the real part of the dielectric function at finite values of the reciprocal lattice vectors. In view of these findings, the task is to calculate the dielectric function for real materials. Then the poles of this function will indicate the existence of bosonic excitations which can …
Prospective Solid-State Photonic Cryocooler Based On The “Phonon-Deficit Effect”, Gurgen Melkonyan, Armen Gulian
Prospective Solid-State Photonic Cryocooler Based On The “Phonon-Deficit Effect”, Gurgen Melkonyan, Armen Gulian
Mathematics, Physics, and Computer Science Faculty Articles and Research
In this design microwave photons are propagating in a sapphire rod, and are being absorbed by a superconductor deposited on the surface of the rod. The frequency of the radiation is tuned to be less than the energy gap in the superconductor, so that the pair breaking is not taking place. This photon pumping redistributes the electron-hole quasiparticles: their distribution function is non-equilibrium, and the “phonon-deficit effect” takes place. There is a dielectric material deposited on top of superconductor, which serves asthe “cold finger” of the cooler. Its “acoustical density” is supposed to be smaller than that of the superconducting …
Power-Recycled Weak-Value-Based Metrology, Kevin Lyons, Justin Dressel, Andrew N. Jordan, John C. Howell, Paul G. Kwiat
Power-Recycled Weak-Value-Based Metrology, Kevin Lyons, Justin Dressel, Andrew N. Jordan, John C. Howell, Paul G. Kwiat
Mathematics, Physics, and Computer Science Faculty Articles and Research
We improve the precision of the interferometric weak-value-based beam deflection measurement by introducing a power recycling mirror, creating a resonant cavity. This results in all the light exiting to the detector with a large deflection, thus eliminating the inefficiency of the rare postselection. The signal-to-noise ratio of the deflection is itself magnified by the weak value. We discuss ways to realize this proposal, using a transverse beam filter and different cavity designs.
Four Tails Problems For Dynamical Collapse Theories, Kelvin J. Mcqueen
Four Tails Problems For Dynamical Collapse Theories, Kelvin J. Mcqueen
Philosophy Faculty Articles and Research
The primary quantum mechanical equation of motion entails that measurements typically do not have determinate outcomes, but result in superpositions of all possible outcomes. Dynamical collapse theories (e.g. GRW) supplement this equation with a stochastic Gaussian collapse function, intended to collapse the superposition of outcomes into one outcome. But the Gaussian collapses are imperfect in a way that leaves the superpositions intact. This is the tails problem. There are several ways of making this problem more precise. But many authors dismiss the problem without considering the more severe formulations. Here I distinguish four distinct tails problems. The first (bare tails …
Mass Additivity And A Priori Entailment, Kelvin J. Mcqueen
Mass Additivity And A Priori Entailment, Kelvin J. Mcqueen
Philosophy Faculty Articles and Research
The principle of mass additivity states that the mass of a composite object is the sum of the masses of its elementary components. Mass additivity is true in Newtonian mechanics but false in special relativity. Physicists have explained why mass additivity is true in Newtonian mechanics by reducing it to Newton’s microphysical laws. This reductive explanation does not fit well with deducibility theories of reductive explanation such as the modern Nagelian theory of reduction, and the a priori entailment theory of reduction that is prominent in the philosophy of mind. Nonetheless, I argue that a reconstruction of the explanation that …
Conservation Of The Spin And Orbital Angular Momenta In Electromagnetism, Konstantin Y. Bliokh, Justin Dressel, Franco Nori
Conservation Of The Spin And Orbital Angular Momenta In Electromagnetism, Konstantin Y. Bliokh, Justin Dressel, Franco Nori
Mathematics, Physics, and Computer Science Faculty Articles and Research
We review and re-examine the description and separation of the spin and orbital angular momenta (AM) of an electromagnetic field in free space. While the spin and orbital AM of light are not separately meaningful physical quantities in orthodox quantum mechanics or classical field theory, these quantities are routinely measured and used for applications in optics. A meaningful quantum description of the spin and orbital AM of light was recently provided by several authors, which describes separately conserved and measurable integral values of these quantities. However, the electromagnetic field theory still lacks corresponding locally conserved spin and orbital AM currents. …
Generalized Helicity And Beltrami Fields, Roman V. Buniy, Thomas W. Kephart
Generalized Helicity And Beltrami Fields, Roman V. Buniy, Thomas W. Kephart
Mathematics, Physics, and Computer Science Faculty Articles and Research
We propose covariant and non-abelian generalizations of the magnetic helicity and Beltrami equation. The gauge invariance, variational principle, conserved current, energy-momentum tensor and choice of boundary conditions elucidate the subject. In particular, we prove that any extremal of the Yang-Mills action functional 1/4 f(Omega) trF(mu nu) F-mu nu d(4)x subject to the local constraint epsilon(mu nu alpha beta)trF(mu nu)F(alpha beta) = 0 satisfies the covariant non-abelian Beltrami equation.
Observation Of A Quantum Cheshire Cat In A Matter-Wave Interferometer Experiment, Tobias Denkmayr, Hermann Geppert, Stephan Sponar, Hartmut Lemmel, Alexandre Matzkin, Jeff Tollaksen, Yuji Hasegawa
Observation Of A Quantum Cheshire Cat In A Matter-Wave Interferometer Experiment, Tobias Denkmayr, Hermann Geppert, Stephan Sponar, Hartmut Lemmel, Alexandre Matzkin, Jeff Tollaksen, Yuji Hasegawa
Mathematics, Physics, and Computer Science Faculty Articles and Research
From its very beginning, quantum theory has been revealing extraordinary and counter-intuitive phenomena, such as wave-particle duality, Schrodinger cats and quantum non-locality. Another paradoxical phenomenon found within the framework of quantum mechanics is the 'quantum Cheshire Cat': if a quantum system is subject to a certain pre- and postselection, it can behave as if a particle and its property are spatially separated. It has been suggested to employ weak measurements in order to explore the Cheshire Cat's nature. Here we report an experiment in which we send neutrons through a perfect silicon crystal interferometer and perform weak measurements to probe …
Quantum Non-Locality Vs. Quasi-Local Measurement In The Conditions Of The Aharonov-Bohm Effect, Armen Gulian
Quantum Non-Locality Vs. Quasi-Local Measurement In The Conditions Of The Aharonov-Bohm Effect, Armen Gulian
Mathematics, Physics, and Computer Science Faculty Articles and Research
Theoretical explanation of the Meissner effect involves proportionality between current density and vector potential, which has many deep consequences. As noticed by de Gennes, superconductors in a magnetic field "find an equilibrium state where the sum of kinetic and magnetic energies is minimum" and this state "corresponds to the expulsion of the magnetic field". This statement still leaves an open question: from which source is the superconducting current acquiring its kinetic energy? A naïve answer, perhaps, is from the energy of the magnetic field. However, one can consider situations (Aharonov-Bohm effect), where the classical magnetic field is locally absent in …
Quantum Harmonic Oscillator With Superoscillating Initial Datum, Roman V. Buniy, Fabrizio Colombo, Irene Sabadini, Daniele C. Struppa
Quantum Harmonic Oscillator With Superoscillating Initial Datum, Roman V. Buniy, Fabrizio Colombo, Irene Sabadini, Daniele C. Struppa
Mathematics, Physics, and Computer Science Faculty Articles and Research
In this paper, we study the evolution of superoscillating initial data for the quantum driven harmonic oscillator. Our main result shows that superoscillations are amplified by the harmonic potential and that the analytic solution develops a singularity in finite time. We also show that for a large class of solutions of the Schrodinger equation, superoscillating behavior at any given time implies superoscillating behavior at any other time.
“Spaghetti” Design For Gravitational Wave Superconducting Antenna, Armen Gulian, J Foreman, Vahan Nikoghosyan, Shmuel Nussinov, Louis Sica, Jeff Tollaksen
“Spaghetti” Design For Gravitational Wave Superconducting Antenna, Armen Gulian, J Foreman, Vahan Nikoghosyan, Shmuel Nussinov, Louis Sica, Jeff Tollaksen
Mathematics, Physics, and Computer Science Faculty Articles and Research
A new concept for detectors of gravitational wave radiation is discussed. Estimates suggest that strain sensitivity essentially better than that of the existing devices can be achieved in the wide frequency range. Such sensitivity could be obtained with devices about one meter long. Suggested device consists of multi-billion bimetallic superconducting wires ("spaghettis") and requires cryogenic operational temperatures (~0.3K in the case considered).
Directed Ratchet Transport In Granular Crystals, Vincent Berardi, J. Lydon, P. G. Kevrekidis, C. Daraio, R. Carretero-González
Directed Ratchet Transport In Granular Crystals, Vincent Berardi, J. Lydon, P. G. Kevrekidis, C. Daraio, R. Carretero-González
Psychology Faculty Articles and Research
Directed-ratchet transport (DRT) in a one-dimensional lattice of spherical beads, which serves as a prototype for granular chains, is investigated. We consider a system where the trajectory of the central bead is prescribed by a biharmonic forcing function with broken time-reversal symmetry. By comparing the mean integrated force of beads equidistant from the forcing bead, two distinct types of directed transport can be observed—spatial and temporal DRT. Based on the value of the frequency of the forcing function relative to the cutoff frequency, the system can be categorized by the presence and magnitude of each type of DRT. Furthermore, we …
Point–Counterpoint: Can Anything Be Learned From Surveys On The Interpretations Of Quantum Mechanics?, Matthew S. Leifer, Nathan Harshman
Point–Counterpoint: Can Anything Be Learned From Surveys On The Interpretations Of Quantum Mechanics?, Matthew S. Leifer, Nathan Harshman
Mathematics, Physics, and Computer Science Faculty Articles and Research
"In what follows, Matt Leifer and Nathan Harshman present opposing views on the value of surveys on foundational attitudes towards quantum mechanics. Three such surveys were recently published and their results are summarized in Table 1. Matt takes the `point,’ arguing that such surveys are not useful, while Nathan takes the `counterpoint.’ A complete set of references for both is given at the end."