Continuous gaussian measurements of the free boson CFT: A model for exactly solvable and detectable measurement-induced dynamics

Hybrid evolution protocols, composed of unitary dynamics and repeated, weak or projective measurements, give rise to new, intriguing quantum phenomena, including entanglement phase transitions and unconventional conformal invariance. Defying the complications imposed by the non-linear and stochastic nature of the measurement process, we introduce a scenario of measurement-induced many body evolution, which possesses an exact analytical solution: bosonic Gaussian measurements. The evolution features a competition between the continuous observation of linear boson operators and a free Hamiltonian, and it is characterized by a unique and exactly solvable covariance matrix. Within this framework, we then consider an elementary model for quantum criticality, the free boson conformal field theory, and investigate in which way criticality is modified under measurements. Depending on the measurement protocol, we distinguish three fundamental scenarios (a) enriched quantum criticality, characterized by a logarithmic entanglement growth with a floating prefactor, or the loss of criticality, indicated by an entanglement growth with either (b) an area-law or (c) a volume-law. For each scenario, we discuss the impact of imperfect measurements, which reduce the purity of the wavefunction and are equivalent to Markovian decoherence, and present a set of observables, e.g., real-space correlations, the relaxation time, and the entanglement structure, to classify the measurement-induced dynamics for both pure and mixed states. Finally, we present an experimental tomography scheme, which grants access to the density operator of the system by using the continuous measurement record only.

Edge Caching in Fog-Based Sensor Networks through Deep Learning-Associated Quantum Computing Framework

Fog computing (FC) based sensor networks have emerged as a propitious archetype for next-generation wireless communication technology with caching, communication, and storage capacity services in the edge. Mobile edge computing (MEC) is a new era of digital communication and has a rising demand for intelligent devices and applications. It faces performance deterioration and quality of service (QoS) degradation problems, especially in the Internet of Things (IoT) based scenarios. Therefore, existing caching strategies need to be enhanced to augment the cache hit ratio and manage the limited storage to accelerate content deliveries. Alternatively, quantum computing (QC) appears to be a prospect of more or less every typical computing problem. The framework is basically a merger of a deep learning (DL) agent deployed at the network edge with a quantum memory module (QMM). Firstly, the DL agent prioritizes caching contents via self organizing maps (SOMs) algorithm, and secondly, the prioritized contents are stored in QMM using a Two-Level Spin Quantum Phenomenon (TLSQP). After selecting the most appropriate lattice map (32 × 32) in 750,000 iterations using SOMs, the data points below the dark blue region are mapped onto the data frame to get the videos. These videos are considered a high priority for trending according to the input parameters provided in the dataset. Similarly, the light-blue color region is also mapped to get medium-prioritized content. After the SOMs algorithm’s training, the topographic error (TE) value together with quantization error (QE) value (i.e., 0.0000235) plotted the most appropriate map after 750,000 iterations. In addition, the power of QC is due to the inherent quantum parallelism (QP) associated with the superposition and entanglement principles. A quantum computer taking “n” qubits that can be stored and execute 2n presumable combinations of qubits simultaneously reduces the utilization of resources compared to conventional computing. It can be analyzed that the cache hit ratio will be improved by ranking the content, removing redundant and least important content, storing the content having high and medium prioritization using QP efficiently, and delivering precise results. The experiments for content prioritization are conducted using Google Colab, and IBM’s Quantum Experience is considered to simulate the quantum phenomena.

Strain-induced circular photogalvanic current in Dirac semimetal Cd3As2 film epitaxied on GaAs (111)B substrate

The Dirac semimetal (DSM) Cd3As2 has drawn great attention for exploring the novel quantum phenomena and high-speed optoelectronic applications. The circular photogalvanic effect (CPGE) current, resulting from the optically-excited spin...

Evidence for interactive common causes. Resuming the Cartwright-Hausman-Woodward debate

The most serious candidates for common causes that fail to screen off (‘interactive common causes’, ICCs) and thus violate the causal Markov condition (CMC) refer to quantum phenomena. In her seminal debate with Hausman and Woodward, Cartwright early on focussed on unfortunate non-quantum examples. Especially, Hausman and Woodward’s redescriptions of quantum cases saving the CMC remain unchallenged. This paper takes up this lose end of the discussion and aims to resolve the debate in favour of Cartwright’s position. It systematically considers redescriptions of ICC structures, including those by Hausman and Woodward, and explains why these are inappropriate, when quantum mechanics (in an objective collapse interpretation) is true. It first shows that all cases of purported quantum ICCs are cases of entanglement and then, using the tools of causal modelling, it provides an analysis of the quantum mechanical formalism for the case that the collapse of entangled systems is best described as a causal model with an ICC.

New Physics II: Spin Picture, Particle Structure, and Fundamental Interactions

Experimental data sometimes fails to render the expected truth, such as high-speed bullets smashing into pieces on a water surface cannot verify the water’s hardness. By re-examining the essence underneath quantum phenomena and analyzing their relevance to universal classical theory, this study has thoroughly revealed the classical counterpart of spin. Subsequently, the equivalence between spin angular momentum (of energy or charge) and vorticity flux (of energy or charge) has also been unveiled, thus intuitively clarifying many abstruse physical concepts, like spin magnetic moment, virtual electron, relativistic time dilation, neutrino chirality, quark origin, and fundamental interactions (including gravitons). From now on, almost all quantum puzzles (e.g., wave-particle duality, quantum entanglement, Schrödinger’s cat) can be understood classically, just as prominent physicists such as Planck, Einstein, and Schrödinger longed for back then. This paper can be considered a blueprint of the Theory of Everything (TOE).

New Physics II: Spin Picture, Particle Structure, and Fundamental Interactions

Experimental data sometimes fails to render the expected truth, such as high-speed bullets smashing into pieces on a water surface cannot verify the water’s hardness. By re-examining the essence underneath quantum phenomena and analyzing their relevance to universal classical theory, this study has thoroughly revealed the classical counterpart of spin. Subsequently, the equivalence between spin angular momentum (of energy or charge) and vorticity flux (of energy or charge) has also been unveiled, thus intuitively clarifying many abstruse physical concepts, like spin magnetic moment, virtual electron, relativistic time dilation, neutrino chirality, quark origin, and fundamental interactions (including gravitons). From now on, almost all quantum puzzles (e.g., wave-particle duality, quantum entanglement, Schrödinger’s cat) can be understood classically, just as prominent physicists such as Planck, Einstein, and Schrödinger longed for back then. This paper can be considered a blueprint of the Theory of Everything (TOE).

New Physics II: Spin Picture, Particle Structure, and Fundamental Interactions

Experimental data sometimes fails to render the expected truth, such as high-speed bullets smashing into pieces on a water surface cannot verify the water’s hardness. By re-examining the essence underneath quantum phenomena and analyzing their relevance to universal classical theory, this study has thoroughly revealed the classical counterpart of spin. Subsequently, the equivalence between spin angular momentum (of energy or charge) and vorticity flux (of energy or charge) has also been unveiled, thus intuitively clarifying many abstruse physical concepts, like spin magnetic moment, virtual electron, relativistic time dilation, neutrino chirality, quark origin, and fundamental interactions (including gravitons). From now on, almost all quantum puzzles (e.g., wave-particle duality, quantum entanglement, Schrödinger’s cat) can be understood classically, just as prominent physicists such as Planck, Einstein, and Schrödinger longed for back then. This paper can be considered a blueprint of the Theory of Everything (TOE).

Randomness and Irreversiblity in Quantum Mechanics: A Worked Example for a Statistical Theory

The randomness of some irreversible quantum phenomena is a central question because irreversible phenomena break quantum coherence and thus yield an irreversible loss of information. The case of quantum jumps observed in the fluorescence of a single two-level atom illuminated by a quasi-resonant laser beam is a worked example where statistical interpretations of quantum mechanics still meet some difficulties because the basic equations are fully deterministic and unitary. In such a problem with two different time scales, the atom makes coherent optical Rabi oscillations between the two states, interrupted by random emissions (quasi-instantaneous) of photons where coherence is lost. To describe this system, we already proposed a novel approach, which is completed here. It amounts to putting a probability on the density matrix of the atom and deducing a general “kinetic Kolmogorov-like” equation for the evolution of the probability. In the simple case considered here, the probability only depends on a single variable θ describing the state of the atom, and p(θ,t) yields the statistical properties of the atom under the joint effects of coherent pumping and random emission of photons. We emphasize that p(θ,t) allows the description of all possible histories of the atom, as in Everett’s many-worlds interpretation of quantum mechanics. This yields solvable equations in the two-level atom case.

New Physics II: Spin Picture, Particle Structure, and Fundamental Interactions

Experimental data sometimes fails to render the expected truth, such as high-speed bullets smashing into pieces on a water surface cannot verify the water’s hardness. By re-examining the essence underneath quantum phenomena and analyzing their relevance to universal classical theory, this study has thoroughly revealed the classical counterpart of spin. Subsequently, the equivalence between spin angular momentum (of energy or charge) and vorticity flux (of energy or charge) has also been unveiled, thus intuitively clarifying many abstruse physical concepts, like spin magnetic moment, virtual electron, relativistic time dilation, neutrino chirality, quark origin, and fundamental interactions (including gravitons). From now on, almost all quantum puzzles (e.g., wave-particle duality, quantum entanglement, Schrödinger’s cat) can be understood classically, just as prominent physicists such as Planck, Einstein, and Schrödinger longed for back then. This paper can be considered a blueprint of the Theory of Everything (TOE).