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Valerii Vinokur

Publications and source records attributed to Valerii Vinokur.

17 recordsLinked to original sources

Information Wells and the Emergence of Primordial Black Holes in a Cyclic Quantum Universe

Primordial black holes (PBHs) remain one of the most intriguing candidates for dark matter and a unique probe of physics at extreme curvatures. Here, we examine their formation in a bounce cosmology when the post-crunch universe inherits a highly inhomogeneous distribution of imprint entropy from the Quantum Memory Matrix (QMM). Within QMM, every Planck-scale cell stores quantum information about infalling matter; the surviving entropy field S(x) contributes an effective dust component T^QMM_{μν} = lambda * [ (nabla_mu S)(nabla_nu S) - (1/2) * g_{μν} * (nabla S)^2 + ... ] that deepens curvature wherever S is large. We show that (i) reasonable bounce temperatures and a QMM coupling lambda ~ O(1) naturally amplify these "information wells" until the density contrast exceeds the critical value delta_c ~ 0.3; (ii) the resulting PBH mass spectrum spans 10^{-16} to 10^3 solar masses, matching current microlensing and PTA windows; and (iii) the same mechanism links PBH abundance to earlier QMM explanations of dark matter and the cosmic matter-antimatter imbalance. Observable signatures include a mild blue tilt in small-scale power, characteristic mu-distortions, and an enhanced integrated Sachs-Wolfe signal - all of which will be tested by upcoming CMB, PTA, and lensing surveys.

physics.gen-ph

Reversible Imprinting and Retrieval of Quantum Information: Experimental Verification of the Quantum Memory Matrix Hypothesis

We report the first end-to-end hardware-validated demonstration of a reversible Quantum Memory Matrix QMM imprint retrieval cycle. Using IBM Quantum back ends, we realize five imprint retrieval experiments that scale from a minimal three-qubit cell to a five-qubit dual cycle. For every circuit, we provide Wilson score 95 percent confidence intervals, Pearson correlations, and mutual information between field and output qubits, establishing unitary reversibility well beyond statistical noise for example, r Q0 Q2 equals 0.64 plus minus 0.04, p less than 10 to the power of minus 6 in the five qubit run. Taken together, the data constitute the most stringent experimental support to date for the QMM hypothesis: finite dimensional Planck scale cells can faithfully store, propagate, and return quantum information. Our results strengthen the standing of QMM as a viable, local, and unitary framework for addressing fundamental questions such as the black hole information paradox.

physics.gen-ph

Tensor networks for quantum computing

In the rapidly evolving field of quantum computing, tensor networks serve as an important tool due to their multifaceted utility. In this paper, we review the diverse applications of tensor networks and show that they are an important instrument for quantum computing. Specifically, we summarize the application of tensor networks in various domains of quantum computing, including simulation of quantum computation, quantum circuit synthesis, quantum error correction and mitigation, and quantum machine learning. Finally, we provide an outlook on the opportunities and the challenges of the tensor-network techniques.

quant-ph

Extending the QMM Framework to the Strong and Weak Interactions

We extend the Quantum Memory Matrix (QMM) framework, originally developed to reconcile quantum mechanics and general relativity by treating space-time as a dynamic information reservoir, to incorporate the full suite of Standard Model gauge interactions. In this discretized, Planck-scale formulation, each space-time cell possesses a finite-dimensional Hilbert space that acts as a local memory, or quantum imprint, for matter and gauge field configurations. We focus on embedding non-Abelian SU(3)c (quantum chromodynamics) and SU(2)L x U(1)Y (electroweak interactions) into QMM by constructing gauge-invariant imprint operators for quarks, gluons, electroweak bosons, and the Higgs mechanism. This unified approach naturally enforces unitarity by allowing black hole horizons, or any high-curvature region, to store and later retrieve quantum information about color and electroweak charges, thereby preserving subtle non-thermal correlations in evaporation processes. Moreover, the discretized nature of QMM imposes a Planck-scale cutoff, potentially taming UV divergences and modifying running couplings at trans-Planckian energies. We outline major challenges, such as the precise formulation of non-Abelian imprint operators and the integration of QMM with loop quantum gravity, as well as possible observational strategies - ranging from rare decay channels to primordial black hole evaporation spectra - that could provide indirect probes of this discrete, memory-based view of quantum gravity and the Standard Model.

physics.gen-ph

Thermodynamic-Complexity Duality: Embedding Computational Hardness as a Thermodynamic Coordinate

We propose a duality between thermodynamics and computational complexity, elevating the difficulty of a computational task to the status of a thermodynamic variable. By introducing a complexity measure C as a novel coordinate, we formulate an extended first law, dU = T dS - p dV + ... + lambda dC, capturing energy costs beyond classical bit erasures. This perspective unifies ideas from Landauer's principle with the combinatorial overhead of hard (e.g., NP-complete) problems, suggesting that algorithmic intractability can manifest as an additional contribution to thermodynamic potentials. We outline how this "complexity potential" might produce phase-transition-like signatures in spin glasses, random constraint satisfaction, or advanced computing hardware near minimal dissipation. We also discuss parallels with previous geometry-information dualities, emphasize the role of complexity in shaping energy landscapes, and propose experimental avenues (in reversible computing or spin-glass setups) to detect subtle thermodynamic signatures of computational hardness. This framework opens a route for systematically incorporating complexity constraints into physical modeling, offering a novel link between the fundamental cost of computation and thermodynamic laws.

physics.gen-ph

Superconducting qubit based on twisted cuprate van der Waals heterostructures

Van-der-Waals (vdW) assembly enables the fabrication of novel Josephson junctions utilizing an atomically sharp interface between two exfoliated and relatively twisted $\rm{Bi_2Sr_2CaCu_2O_{8+x}}$ (Bi2212) flakes. In a range of twist angles around $45^\circ$, the junction provides a regime where the interlayer two-Cooper pair tunneling dominates the current-phase relation. Here we propose to employ this novel junction to realize a capacitively shunted qubit that we call flowermon. The $d$-wave nature of the order parameter endows the flowermon with inherent protection against charge-noise-induced relaxation and quasiparticle-induced dissipation. This inherently protected qubit paves the way to a new class of high-coherence hybrid superconducting quantum devices based on unconventional superconductors.

cond-mat.supr-con

Practical application-specific advantage through hybrid quantum computing

Quantum computing promises to tackle technological and industrial problems insurmountable for classical computers. However, today's quantum computers still have limited demonstrable functionality, and it is expected that scaling up to millions of qubits is required for them to live up to this touted promise. The feasible route in achieving practical quantum advantage goals is to implement a hybrid operational mode that realizes the cohesion of quantum and classical computers. Here we present a hybrid quantum cloud based on a memory-centric and heterogeneous multiprocessing architecture, integrated into a high-performance computing data center grade environment. We demonstrate that utilizing the quantum cloud, our hybrid quantum algorithms including Quantum Encoding (QuEnc), Hybrid Quantum Neural Networks and Tensor Networks enable advantages in optimization, machine learning, and simulation fields. We show the advantage of hybrid algorithms compared to standard classical algorithms in both the computational speed and quality of the solution. The achieved advance in hybrid quantum hardware and software makes quantum computing useful in practice today.

quant-ph

Tensor Network Quantum Simulator With Step-Dependent Parallelization

In this work, we present a new large-scale quantum circuit simulator. It is based on the tensor network contraction technique to represent quantum circuits. We propose a novel parallelization algorithm based on \stepslice . In this paper, we push the requirement on the size of a quantum computer that will be needed to demonstrate the advantage of quantum computation with Quantum Approximate Optimization Algorithm (QAOA). We computed 210 qubit QAOA circuits with 1,785 gates on 1,024 nodes of the the Cray XC 40 supercomputer Theta. To the best of our knowledge, this constitutes the largest QAOA quantum circuit simulations reported to this date.

quant-ph

Dynamic Vortex-Mott Transition in 2D Superconducting Proximity Arrays

The paradigmatic Mott insulator arises in strongly correlated systems, where strong local repulsion localizes interacting particles in underlying egg-holder-like potential. The corresponding Mott transition reflects delocalization of the charges either by varying parameters of the system and temperature, or by applied current, the latter being referred to as the dynamic Mott transition. Recently, the dynamic Mott transition was experimentally observed on the vortex system trapped by the periodic proximity array and described in terms of non-Hermitian theory of nonequilibrium processes. Here we investigate numerically the vortex dynamic Mott transition in an proximity array implemented as an array of holes in a superconducting films and discover striking nonmonotonic behavior of the differential resistance as function of the applied current when deviating from the matching field corresponding to a unity filling factor.

cond-mat.supr-con

Disordered BKT transition and superinsulation

Strongly disordered superconducting films have been observed to undergo finite temperature transitions to a superinsulating state, of apparently infinite resistance, mirroring superconductivity. Approaching the transition, some of the films reportedly exhibit Berezinskii-Kosterlitz-Thouless (BKT) criticality implying that superinsulation is associated with an ordered charge BKT phase. An even more singular Vogel-Fulcher-Tammann (VFT) criticality has also been seen, positing the question of the existence of fundamentally different states of finite temperature insulators. Here we develop a theory of the criticality of a disordered lateral Josephson junction array with weak Josephson coupling. We show that it is equivalent to a two-dimensional Coulomb gas with logarithmically correlated disorder. We show that strong disorder results in a regime exhibiting VFT criticality instead of the usual BKT one, and find that it corresponds to transition to a nonergodic insulator phase.

cond-mat.supr-con

Terahertz Electrodynamics of $180^\circ$ Domain Walls in Thin Ferroelectric Films

We investigate oscillation dynamics of a periodic structure of the $180^\circ$ domain walls in nanometricaly thin substrate-deposited ferroelectric films and superlattices. We calculate dynamic permittivity of such structures and reveal a collective resonance mode, which in the typical ferroelectric compounds, PbTiO3/SrTiO3, lies in the sub- and low THz frequency range of 0.3-3THz. We propose the reflection-absorbtion spectroscopy experiments to observe this mode.

cond-mat.mtrl-sci

Effect of half-quantum vortices on magnetoresistance of perforated superconducting films

Recent cantilever magnetometry measurements of annular micron-size samples of Sr2RuO4 have revealed evidence for the existence of half-quantum vortices (HQVs) in this material [Jang et al. 2011]. We propose to look for HQVs in transport measurements and calculate magnetoresistance of a perforated superconducting film close to the transition temperature in the presence of HQVs. We analyze the dependence of magnetoresistance on the thermodynamic stability of HQVs which according to [Jang et al. 2011] can be varied by the application of an in-plane magnetic field and point out features which may help to identify them.

cond-mat.supr-con

Creep motions of flux lines in type II superconductors with point-like defects

We simulated the creep motions of flux lines subject to randomly distributed point-like pinning centers. It is found that at low temperatures, the pinning barrier $U$ defined in the Arrhenius-type $v-F$ characteristics increases with decreasing force $U(F) \propto F^{-μ}$, as predicted by previous theories. The exponent $μ$ is evaluated as $0.28\pm 0.02 $ for the vortex glass and $μ\simeq 0.5\pm 0.02$ for the Bragg glass (BrG). The latter is in good agreement with the prediction by the scaling theory and the functional-renormalization-group theory on creep, while the former is a new estimate. Within BrG, we find that the pinning barrier is suppressed when temperature is lifted to approximately half of the melting temperature. Characterizations of this new transition at equilibrium are also presented, indicative of a phase transition associated with the replica-symmetry breaking.

cond-mat.supr-con

Vortex avalanches and magnetic flux fragmentation in superconductors

We report results of numerical simulations of non isothermal dendritic flux penetration in type-II superconductors. We propose a generic mechanism of dynamic branching of a propagating hotspot of a flux flow/normal state triggered by a local heat pulse. The branching occurs when the flux hotspot reflects from inhomogeneities or the boundary on which magnetization currents either vanish, or change direction. Then the hotspot undergoes a cascade of successive splittings, giving rise to a dissipative dendritic-type flux structure. This dynamic state eventually cools down, turning into a frozen multi-filamentary pattern of magnetization currents.

cond-mat.supr-con

Evolution on a Rugged Landscape:Pinning and Aging

Population dynamics on a rugged landscape is studied analytically and numerically within a simple discrete model for evolution of N individuals in one-dimensional fitness space. We reduce the set of master equations to a single Fokker-Plank equation which allows us to describe the dynamics of the population in terms of thermo-activated Langevin diffusion of a single particle in a specific random potential. We found that the randomness in the mutation rate leads to pinning of the population and on average to a logarithmic slowdown of the evolution, resembling aging phenomenon in spin glass systems. In contrast, the randomness in the replication rate turns out to be irrelevant for evolution in the long-time limit as it is smoothed out by increasing ``evolution temperature''. The analytic results are in a good agreement with numerical simulations.

adap-org

Gliding dislocations in a driven vortex lattice

The dynamics of dislocations in a two-dimensional vortex lattice is studied in the presence of a pinning potential and a transport current. In a vortex lattice drifting with velocity $v$ a glide velocity $V_d$ of the dislocation with respect to the vortex lattice is found to decay like $V_d \sim v^{-4}$ for large drive. From this result the velocity for the crossover between a regime of coherent elastic motion and a regime of incoherent plastic motion of vortices is estimated.

cond-mat.supr-con

Hysteretic creep of elastic manifolds

We study the dynamic response of driven systems in the presence of quenched disorder. A simple heuristic model for hysteretic creep of elastic manifolds is proposed and evaluated numerically. It provides a qualitative explanation of the phenomenology observed in experiments on high-temperature superconductors.

cond-mat