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Articles 91 - 120 of 252
Full-Text Articles in Quantum Physics
Noncontextuality Inequalities From Antidistinguishability, Matthew S. Leifer, Cristhiano Duarte
Noncontextuality Inequalities From Antidistinguishability, Matthew S. Leifer, Cristhiano Duarte
Mathematics, Physics, and Computer Science Faculty Articles and Research
Noncontextuality inequalities are usually derived from the distinguishability properties of quantum states, i.e., their orthogonality. Here, we show that antidistinguishability can also be used to derive noncontextuality inequalities. The Yu-Oh 13-ray noncontextuality inequality can be rederived and generalized as an instance of our antidistinguishability method. For some sets of states, the antidistinguishability method gives tighter bounds on noncontextual models than just considering orthogonality, and the Hadamard states provide an example of this. We also derive noncontextuality inequalities based on mutually unbiased bases and symmetric informationally complete positive operator-valued measures. Antidistinguishability based inequalities were initially discovered as overlap bounds for the …
On Quantum Effects Of Vector Potentials And Generalizations Of Functional Analysis, Ismael L. Paiva
On Quantum Effects Of Vector Potentials And Generalizations Of Functional Analysis, Ismael L. Paiva
Computational and Data Sciences (PhD) Dissertations
This is a dissertation in two parts. In the first one, the Aharonov-Bohm effect is investigated. It is shown that solenoids (or flux lines) can be seen as barriers for quantum charges. In particular, a charge can be trapped in a sector of a long cavity by two flux lines. Also, grids of flux lines can approximate the force associated with continuous two-dimensional distributions of magnetic fields. More, if it is assumed that the lines can be as close to each other as desirable, it is explained how the classical magnetic force can emerge from the Aharonov-Bohm effect. Continuing, the …
Magnetic Forces In The Absence Of A Classical Magnetic Field, Ismael L. Paiva, Yakir Aharonov, Jeff Tollaksen, Mordecai Waegell
Magnetic Forces In The Absence Of A Classical Magnetic Field, Ismael L. Paiva, Yakir Aharonov, Jeff Tollaksen, Mordecai Waegell
Mathematics, Physics, and Computer Science Faculty Articles and Research
It is shown that, in some cases, the effect of discrete distributions of flux lines in quantum mechanics can be associated with the effect of continuous distributions of magnetic fields with special symmetries. In particular, flux lines with an arbitrary value of magnetic flux can be used to create energetic barriers, which can be used to confine quantum systems in specially designed configurations. This generalizes a previous work where such energy barriers arose from flux lines with half-integer fluxons. Furthermore, it is shown how the Landau levels can be obtained from a two-dimensional grid of flux lines. These results suggest …
Footprints Of Quantum Pigeons, Gregory Reznick, Shrobona Bagchi, Justin Dressel, Lev Vaidman
Footprints Of Quantum Pigeons, Gregory Reznick, Shrobona Bagchi, Justin Dressel, Lev Vaidman
Mathematics, Physics, and Computer Science Faculty Articles and Research
We show that in the mathematical framework of the quantum theory, the classical pigeonhole principle can be violated more directly than previously suggested, i.e., in a setting closer to the traditional statement of the principle. We describe how the counterfactual reasoning of the paradox may be operationally grounded in the analysis of the tiny footprints left in the environment by the pigeons. After identifying the drawbacks of recent experiments of the quantum pigeonhole effect, we argue that a definitive experimental violation of the pigeonhole principle is still needed and propose such an implementation using modern quantum computing hardware: a superconducting …
Reformulating Bell's Theorem: The Search For A Truly Local Quantum Theory, Mordecai Waegell, Kelvin J. Mcqueen
Reformulating Bell's Theorem: The Search For A Truly Local Quantum Theory, Mordecai Waegell, Kelvin J. Mcqueen
Philosophy Faculty Articles and Research
The apparent nonlocality of quantum theory has been a persistent concern. Einstein et al. (1935) and Bell (1964) emphasized the apparent nonlocality arising from entanglement correlations. While some interpretations embrace this nonlocality, modern variations of the Everett-inspired many worlds interpretation try to circumvent it. In this paper, we review Bell's “no-go” theorem and explain how it rests on three axioms, local causality, no superdeterminism, and one world. Although Bell is often taken to have shown that local causality is ruled out by the experimentally confirmed entanglement correlations, we make clear that it is the conjunction of the …
Optimizing Measurement Strengths For Qubit Quasiprobabilities Behind Out-Of-Time-Ordered Correlators, Razieh Mohseninia, José Raúl González Alonso, Justin Dressel
Optimizing Measurement Strengths For Qubit Quasiprobabilities Behind Out-Of-Time-Ordered Correlators, Razieh Mohseninia, José Raúl González Alonso, Justin Dressel
Mathematics, Physics, and Computer Science Faculty Articles and Research
Out-of-time-ordered correlators (OTOCs) have been proposed as a tool to witness quantum information scrambling in many-body system dynamics. These correlators can be understood as averages over nonclassical multitime quasiprobability distributions (QPDs). These QPDs have more information and their nonclassical features witness quantum information scrambling in a more nuanced way. However, their high dimensionality and nonclassicality make QPDs challenging to measure experimentally. We focus on the topical case of a many-qubit system and show how to obtain such a QPD in the laboratory using circuits with three and four sequential measurements. Averaging distinct values over the same measured distribution reveals either …
Schrödinger Evolution Of Superoscillations With Δ - And Δ′ -Potentials, Yakir Aharonov, Jussi Behrndt, Fabrizio Colombo, Peter Schlosser
Schrödinger Evolution Of Superoscillations With Δ - And Δ′ -Potentials, Yakir Aharonov, Jussi Behrndt, Fabrizio Colombo, Peter Schlosser
Mathematics, Physics, and Computer Science Faculty Articles and Research
In this paper, we study the time persistence of superoscillations as the initial data of the time-dependent Schrödinger equation with δ- and δ′-potentials. It is shown that the sequence of solutions converges uniformly on compact sets, whenever the initial data converge in the topology of the entire function space A1(C). Convolution operators acting in this space are our main tool. In particular, a general result about the existence of such operators is proven. Moreover, we provide an explicit formula as well as the large time asymptotics for the time evolution of a plane wave under δ- and δ′-potentials.
Topological Bound States For Quantum Charges, Yakir Aharonov, Ismael L. Paiva, Jeff Tollaksen, Mordecai Waegell
Topological Bound States For Quantum Charges, Yakir Aharonov, Ismael L. Paiva, Jeff Tollaksen, Mordecai Waegell
Mathematics, Physics, and Computer Science Faculty Articles and Research
We discuss how, in appropriately designed configurations, solenoids carrying a semifluxon can be used as topological energy barriers for charged quantum systems. We interpret this phenomenon as a consequence of the fact that such solenoids induce nodal lines in the wave function describing the charge, which on itself is a consequence of the Aharonov-Bohm effect. Moreover, we present a thought experiment with a cavity where two solenoids are sufficient to create bound states.
Diffraction-Based Interaction-Free Measurements, Spencer Rogers, Yakir Aharonov, Cyril Elouard, Andrew N. Jordan
Diffraction-Based Interaction-Free Measurements, Spencer Rogers, Yakir Aharonov, Cyril Elouard, Andrew N. Jordan
Mathematics, Physics, and Computer Science Faculty Articles and Research
We introduce diffraction-based interaction-free measurements. In contrast with previous work where a set of discrete paths is engaged, good-quality interaction-free measurements can be realized with a continuous set of paths, as is typical of optical propagation. If a bomb is present in a given spatial region—so sensitive that a single photon will set it off—its presence can still be detected without exploding it. This is possible because, by not absorbing the photon, the bomb causes the single photon to diffract around it. The resulting diffraction pattern can then be statistically distinguished from the bomb-free case. We work out the case …
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 …
The Nature Of The Heisenberg-Von Neumann Cut: Enhanced Orthodox Interpretation Of Quantum Mechanics, Ashok Narasimhan, Deepak Chopra, Menas Kafatos
The Nature Of The Heisenberg-Von Neumann Cut: Enhanced Orthodox Interpretation Of Quantum Mechanics, Ashok Narasimhan, Deepak Chopra, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
We examine the issue of the Heisenberg-von Neumann cut in light of recent interpretations of quantum eraser experiments which indicate the possibility of a universal Observer outside space-time at an information level of existence. The delayed-choice aspects of observation, measurement, the role of the observer, and information in the quantum framework of the universe are discussed. While traditional double-slit experiments are usually interpreted as indicating that the collapse of the wave function involves choices by an individual observer in space-time, the extension to quantum eraser experiments brings in some additional subtle aspects relating to the role of observation and what …
Roadmap On Superoscillations, Michael Berry, Nicolay Zheludev, Yakir Aharonov, Fabrizio Colombo, Irene Sabadini, Daniele C. Struppa, Jeff Tollaksen, Edward T. F. Rogers, Fei Qin, Minghui Hong, Xiangang Luo, Roei Remez, Ady Arie, Jörg B. Götte, Mark R. Dennis, Alex M. H. Wong, George V. Eleftheriades, Yaniv Eliezer, Alon Bahabad, Gang Chen, Zhongquan Wen, Gaofeng Liang, Chenglong Hao, C-W Qiu, Achim Kempf, Eytan Katzav, Moshe Schwartz
Roadmap On Superoscillations, Michael Berry, Nicolay Zheludev, Yakir Aharonov, Fabrizio Colombo, Irene Sabadini, Daniele C. Struppa, Jeff Tollaksen, Edward T. F. Rogers, Fei Qin, Minghui Hong, Xiangang Luo, Roei Remez, Ady Arie, Jörg B. Götte, Mark R. Dennis, Alex M. H. Wong, George V. Eleftheriades, Yaniv Eliezer, Alon Bahabad, Gang Chen, Zhongquan Wen, Gaofeng Liang, Chenglong Hao, C-W Qiu, Achim Kempf, Eytan Katzav, Moshe Schwartz
Mathematics, Physics, and Computer Science Faculty Articles and Research
Superoscillations are band-limited functions with the counterintuitive property that they can vary arbitrarily faster than their fastest Fourier component, over arbitrarily long intervals. Modern studies originated in quantum theory, but there were anticipations in radar and optics. The mathematical understanding—still being explored—recognises that functions are extremely small where they superoscillate; this has implications for information theory. Applications to optical vortices, sub-wavelength microscopy and related areas of nanoscience are now moving from the theoretical and the demonstrative to the practical. This Roadmap surveys all these areas, providing background, current research, and anticipating future developments.
Realization Of Tensor Product And Of Tensor Factorization Of Rational Functions, Daniel Alpay, Izchak Lewkowicz
Realization Of Tensor Product And Of Tensor Factorization Of Rational Functions, Daniel Alpay, Izchak Lewkowicz
Mathematics, Physics, and Computer Science Faculty Articles and Research
We study the state space realization of a tensor product of a pair of rational functions. At the expense of “inflating” the dimensions, we recover the classical expressions for realization of a regular product of rational functions. Under an additional assumption that the limit at infinity of a given rational function exists and is equal to identity, we introduce an explicit formula for a tensor factorization of this function.
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 …
Modification Of Counterfactual Communication Protocols That Eliminates Weak Particle Traces, Yakir Aharonov, Lev Vaidman
Modification Of Counterfactual Communication Protocols That Eliminates Weak Particle Traces, Yakir Aharonov, Lev Vaidman
Mathematics, Physics, and Computer Science Faculty Articles and Research
The possibility to communicate between spatially separated regions, without even a single photon passing between the two parties, is an amazing quantum phenomenon. The possibility of transmitting one value of a bit in such a way, the interaction-free measurement, has been known for quarter of a century. The protocols of full communication, including transmitting unknown quantum states, were proposed only a few years ago, but it was shown that in all these protocols the particle was leaving a weak trace in the transmission channel, the trace being larger than the trace left by a single particle passing through the channel. …
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 …
In Defence Of The Self-Location Uncertainty Account Of Probability In The Many-Worlds Interpretation, Kelvin J. Mcqueen, Lev Vaidman
In Defence Of The Self-Location Uncertainty Account Of Probability In The Many-Worlds Interpretation, Kelvin J. Mcqueen, Lev Vaidman
Philosophy Faculty Articles and Research
We defend the many-worlds interpretation of quantum mechanics (MWI) against the objection that it cannot explain why measurement outcomes are predicted by the Born probability rule. We understand quantum probabilities in terms of an observer's self-location probabilities. We formulate a probability postulate for the MWI: the probability of self-location in a world with a given set of outcomes is the absolute square of that world's amplitude. We provide a proof of this postulate, which assumes the quantum formalism and two principles concerning symmetry and locality. We also show how a structurally similar proof of the Born rule is available for …
Gravitational Sensing With Weak Value Based Optical Sensors, Andrew N. Jordan, Philippe Lewalle, Jeff Tollaksen, John C. Howell
Gravitational Sensing With Weak Value Based Optical Sensors, Andrew N. Jordan, Philippe Lewalle, Jeff Tollaksen, John C. Howell
Mathematics, Physics, and Computer Science Faculty Articles and Research
Using weak value amplification angular resolution limits, we theoretically investigate the gravitational sensing of objects. By inserting a force-sensing pendulum into a weak value interferometer, the optical response can sense accelerations to a few 10’s of zepto-g Hz-1/2, with optical powers of 1 mW. We convert this precision into range and mass sensitivity, focusing in detail on simple and torsion pendula. Various noise sources present are discussed, as well as the necessary cooling that should be applied to reach the desired levels of precision.
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 …
The Weak Reality That Makes Quantum Phenomena More Natural: Novel Insights And Experiments, Yakir Aharonov, Eliahu Cohen, Mordecai Waegell, Avshalom C. Elitzur
The Weak Reality That Makes Quantum Phenomena More Natural: Novel Insights And Experiments, Yakir Aharonov, Eliahu Cohen, Mordecai Waegell, Avshalom C. Elitzur
Mathematics, Physics, and Computer Science Faculty Articles and Research
While quantum reality can be probed through measurements, the Two-State Vector Formalism (TSVF) reveals a subtler reality prevailing between measurements. Under special pre- and post-selections, odd physical values emerge. This unusual picture calls for a deeper study. Instead of the common, wave-based picture of quantum mechanics, we suggest a new, particle-based perspective: Each particle possesses a definite location throughout its evolution, while some of its physical variables (characterized by deterministic operators, some of which obey nonlocal equations of motion) are carried by “mirage particles” accounting for its unique behavior. Within the time interval between pre- and post-selection, the particle gives …
Strengthening Weak Measurements Of Qubit Out-Of-Time-Order Correlators, Justin Dressel, José Raúl González Alonso, Mordecai Waegell, Nicole Yunger Halpern
Strengthening Weak Measurements Of Qubit Out-Of-Time-Order Correlators, Justin Dressel, José Raúl González Alonso, Mordecai Waegell, Nicole Yunger Halpern
Mathematics, Physics, and Computer Science Faculty Articles and Research
For systems of controllable qubits,we provide amethod for experimentally obtaining a useful class of multitime correlators using sequential generalized measurements of arbitrary strength. Specifically, if a correlator can be expressed as an average of nested (anti)commutators of operators that square to the identity, then that correlator can be determined exactly from the average of a measurement sequence. As a relevant example, we provide quantum circuits for measuring multiqubit out-of-time-order correlators using optimized control-Z or ZX-90 two-qubit gates common in superconducting transmon implementations.
Quantum Mechanics And Global Determinism, Emily Christine Adlam
Quantum Mechanics And Global Determinism, Emily Christine Adlam
Mathematics, Physics, and Computer Science Faculty Articles and Research
It is proposed that certain features of quantum mechanics may be perspectival effects, which arise because experiments performed on locally accessible variables can only uncover a certain subset of the correlations exhibited by an underlying deterministic theory. This hypothesis is used to derive the no-signaling principle, thus resolving an open question regarding the apparently fine-tuned nature of quantum correlations. Some potential objections to this approach are then discussed and answered.
Extraordinary Interactions Between Light And Matter Determined By Anomalous Weak Values, Yakir Aharonov, Eliahu Cohen, Avishy Carmi, Avshalom C. Elitzur
Extraordinary Interactions Between Light And Matter Determined By Anomalous Weak Values, Yakir Aharonov, Eliahu Cohen, Avishy Carmi, Avshalom C. Elitzur
Mathematics, Physics, and Computer Science Faculty Articles and Research
Some predictions regarding pre- and post-selected states are far-reaching, thereby requiring validation with standard quantum measurements in addition to the customary weak measurements used so far, as well as other advanced techniques. We go further pursuing this goal, proposing two thought experiments which incorporate novel yet feasible validation methods of unconventional light-matter interactions. An excited atom traverses a Mach–Zehnder interferometer (MZI) under a special combination of pre- and post-selection. In the first experiment, photons emitted by the superposed atom, after being hit by two laser beams, are individually counted. Despite the interaction having definitely taken place, as revealed by the …
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 …
Is The Quilted Multiverse Consistent With A Thermodynamic Arrow Of Time?, Yakir Aharonov, Eliahu Cohen, Tomer Shushi
Is The Quilted Multiverse Consistent With A Thermodynamic Arrow Of Time?, Yakir Aharonov, Eliahu Cohen, Tomer Shushi
Mathematics, Physics, and Computer Science Faculty Articles and Research
Theoretical achievements, as well as much controversy, surround multiverse theory. Various types of multiverses, with an increasing amount of complexity, were suggested and thoroughly discussed in literature by now. While these types are very different, they all share the same basic idea: our physical reality consists of more than just one universe. Each universe within a possibly huge multiverse might be slightly or even very different from the others. The quilted multiverse is one of these types, whose uniqueness arises from the postulate that every possible event will occur infinitely many times in infinitely many universes. In this paper we …
Knowledge-Concealing Evidencing Of Knowledge About A Quantum State, Emily Adlam, Adrian Kent
Knowledge-Concealing Evidencing Of Knowledge About A Quantum State, Emily Adlam, Adrian Kent
Mathematics, Physics, and Computer Science Faculty Articles and Research
Bob has a black box that emits a single pure state qudit which is, from his perspective, uniformly distributed. Alice wishes to give Bob evidence that she has knowledge about the emitted state while giving him little or no information about it. We show that zero-knowledge evidencing of such knowledge is impossible in quantum relativistic protocols, extending a previous result of Horodecki, Horodecki, and Horodecki. We also show that no such protocol can be both sound and complete. We present a new quantum relativistic protocol which we conjecture to be close to optimal in security against Alice and which reveals …
Incoherent Qubit Control Using The Quantum Zeno Effect, S. Hachohen-Gourgy, L. P. García-Pintos, L. S. Martin, Justin Dressel, I. Siddiqi
Incoherent Qubit Control Using The Quantum Zeno Effect, S. Hachohen-Gourgy, L. P. García-Pintos, L. S. Martin, Justin Dressel, I. Siddiqi
Mathematics, Physics, and Computer Science Faculty Articles and Research
The quantum Zeno effect is the suppression of Hamiltonian evolution by repeated observation, which pins the system to an eigenstate of the measurement observable. Using measurement alone, control of the state can be achieved if the observable is slowly varied, so that the state tracks the now time-dependent eigenstate. We demonstrate this using a circuit-QED readout technique that couples to a dynamically controllable observable of a qubit. Continuous monitoring of the measurement record allows us to detect an escape from the eigenstate, thus serving as a built-in form of error detection. We show this by postselecting on realizations with high …
Spooky Action At A (Temporal) Distance, Emily Adlam
Spooky Action At A (Temporal) Distance, Emily Adlam
Mathematics, Physics, and Computer Science Faculty Articles and Research
Since the discovery of Bell’s theorem, the physics community has come to take seriously the possibility that the universe might contain physical processes which are spatially nonlocal, but there has been no such revolution with regard to the possibility of temporally nonlocal processes. In this article, we argue that the assumption of temporal locality is actively limiting progress in the field of quantum foundations. We investigate the origins of the assumption, arguing that it has arisen for historical and pragmatic reasons rather than good scientific ones, then explain why temporal locality is in tension with relativity and review some recent …
Geometroneurodynamics And Neuroscience, Keun-Hang Susan Yang, Menas Kafatos
Geometroneurodynamics And Neuroscience, Keun-Hang Susan Yang, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
The Orthodox Interpretation of quantum mechanics, as developed by many physicists, particularly John von Neumann, addresses the role of measurement, available choices and response of the quantum system to questions posed by an observer in specific quantum laboratory experiments. As such, it is, more consistent and clearer than other interpretations of quantum mechanics and it provides an account of the interactions of observers with the external world. However, in order to explore whether quantum mechanics plays a role in the brain, which is the primary issue, one has to examine the applicability of Hilbert space structure as a valid geometric …