cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Temperature effect on the small-to-large crossover length-scale of hydrophobic hydration
Creators: name: Djikaev, Yuri S.
name: Ruckenstein, Eli
Publisher: name: arXiv
Year: 2013
Subjects: subject: Soft Condensed Matter (cond-mat.soft)
subject: Chemical Physics (physics.chem-ph)
subject: FOS: Physical sciences

description: The thermodynamics of hydration changes gradually from entropic for small solutes to enthalpic for large ones. The small-to-large crossover lengthscale of hydrophobic hydration depends on the thermodynamic conditions of the solvent such as temperature, pressure, presence of additives, etc... We attempt to shed some light on the temperature dependence of the crossover lengthscale by using a probabilistic approach to water hydrogen bonding that allows one to obtain an analytic expression for the number of bonds per water molecule as a function of both its distance to a solute and solute radius. Incorporating that approach into the density functional theory, one can examine the solute size effects on its hydration over the entire small-to-large lengthscale range at different temperatures. Knowing the dependence of the hydration free energy on temperature and solute size, one can obtain its enthalpic and entropic contributions as functions of temperature and solute size. These function can provide interesting insight into the temperature dependence of the crossover lengthscale of hydrophobic hydration. The model was applied to the hydration of spherical particles of various radii in water in the temperature range from T=293.15 K to T=333.15 K. The model predictions for the temperature dependence of the hydration free energy of small hydrophobes are consistent with the experimental and simulational data. Three alternative definitions for the small-to-large crossover length-scale of hydrophobic hydration are proposed, and their temperature dependence is obtained. Depending on the definition and temperature, the small-to-large crossover in the hydration mechanism is predicted to occur for hydrophobes of radii from one to several nanometers. Independent of its definition, the crossover length-scale is predicted to decrease with increasing temperature.
description: arXiv admin note: substantial text overlap with arXiv:1303.4429
Tensor network investigation of the hard-square model
Creators: name: Nyckees, Samuel
name: Mila, Frédéric
Publisher: name: arXiv
Year: 2022
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: Using the corner-transfer matrix renormalization group to contract the tensor network that describes its partition function, we investigate the nature of the phase transitions of the hard-square model, one of the exactly solved models of statistical physics for which Baxter has found an integrable manifold. The motivation is twofold: assess the power of tensor networks for such models, and probe the 2D classical analog of a 1D quantum model of hard-core bosons that has recently attracted significant attention in the context of experiments on chains of Rydberg atoms. Accordingly, we concentrate on two planes in the 3D parameter space spanned by the activity and the coupling constants in the two diagonal directions. We first investigate the only case studied so far with Monte Carlo simulations, the case of opposite coupling constants. We confirm that, away and not too far from the integrable 3-state Potts point, the transition out of the period-3 phase appears to be unique in the Huse-Fisher chiral universality class, albeit with significantly different exponents as compared to Monte Carlo. We also identify two additional phase transitions not reported so far for that model, a Lifshitz disorder line, and an Ising transition for large enough activity. To make contact with 1D quantum models of Rydberg atoms, we then turn to a plane where the ferromagnetic coupling is kept fixed, and we show that the resulting phase diagram is very similar, the only difference being that the Ising transition becomes first-order through a tricritical Ising point, in agreement with Baxter's prediction that this plane should contain a tricritical Ising point, and in remarkable, almost quantitative agreement with the phase diagram of the 1D quantum version of the model.
Dynamic hysteretic features of the Ising-type thin films
Creators: name: Aktaş, Bahadır Ozan
name: Akıncı, Ümit
name: Polat, Hamza
Publisher: name: arXiv
Year: 2013
Subjects: subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: In order to elucidate the important characteristics of hysteretic response, such as types of the frequency dispersion curves, the decay of hysteresis loop area, the mechanism of domain nucleation and/or growth in the dynamic process, etc., a followup examination after the original work has been presented. The additive complementary treatment is essentially based on the results of recent preprint arXiv:1302.2727 concerning the effect of oscillatory perturbation on the surface enhancement phenomenon in magnetic thin films. Throughout the analysis, the best appropriate parameter values have been chosen since they would allow us to achieve striking results. The topology of the response for different layer indices in two regimes of modified surface exchange has been particularly emphasized.
description: 8 pages, 4 figures. arXiv admin note: text overlap with arXiv:1302.2727
Anomalous Diffuse Interstellar Bands in the Spectrum of Herschel 36. II. Analysis of Radiatively Excited CH+, CH, and DIBs
Creators: name: Oka, Takeshi
name: Welty, Daniel E.
name: Johnson, Sean
name: York, Donald G.
name: Dahlstrom, Julie
name: Hobbs, L. M.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: Absorption spectra toward Herschel 36 for the A^1Pi 50 K). Although modeling for general molecules is beyond the scope of this paper, the results indicate that the prototypical DIBs at 5780.5, 5797.1, and 6613.6 A which show the pronounced ETRs are due to polar molecules sensitive to the radiative excitation. The requirement of high beta favors relatively small molecules with 3-6 heavy atoms. DIBs at 5849.8, 6196.0, and 6379.3 A which do not show the pronounced ETRs are likely due to non-polar molecules or large polar molecules with small beta.
description: 35 pages; 5 figures; accepted to ApJ; corrected minor errors in eqns. 3, 6, and 8 and fig. 4; conclusions unchanged
Quantum battery based on superabsorption
Creators: name: Ueki, Yudai
name: Kamimura, Shunsuke
name: Matsuzaki, Yuichiro
name: Yoshida, Kyo
name: Tokura, Yasuhiro
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: A quantum battery is a device where an energy is charged by using a quantum effect. Here, we propose a quantum battery with a charger system composed of $N$ qubits by utilizing a collective effect called a superabsorption. Importantly, the coupling strength between the quantum battery and charger system can be enhanced due to an entanglement. While the charger time scales as $Θ\left(N^{-1/2}\right)$ by applying a conventional scheme, we can achieve a charging time $Θ\left(N^{-1}\right)$ in our scheme. Our results open the path to ultra-fast charging of a quantum battery.
Exploiting Digital Surface Models for Inferring Super-Resolution for Remotely Sensed Images
Creators: name: Karatsiolis, Savvas
name: Padubidri, Chirag
name: Kamilaris, Andreas
Publisher: name: arXiv
Year: 2022
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Machine Learning (cs.LG)
subject: Image and Video Processing (eess.IV)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Despite the plethora of successful Super-Resolution Reconstruction (SRR) models applied to natural images, their application to remote sensing imagery tends to produce poor results. Remote sensing imagery is often more complicated than natural images and has its peculiarities such as being of lower resolution, it contains noise, and often depicting large textured surfaces. As a result, applying non-specialized SRR models on remote sensing imagery results in artifacts and poor reconstructions. To address these problems, this paper proposes an architecture inspired by previous research work, introducing a novel approach for forcing an SRR model to output realistic remote sensing images: instead of relying on feature-space similarities as a perceptual loss, the model considers pixel-level information inferred from the normalized Digital Surface Model (nDSM) of the image. This strategy allows the application of better-informed updates during the training of the model which sources from a task (elevation map inference) that is closely related to remote sensing. Nonetheless, the nDSM auxiliary information is not required during production and thus the model infers a super-resolution image without any additional data besides its low-resolution pairs. We assess our model on two remotely sensed datasets of different spatial resolutions that also contain the DSM pairs of the images: the DFC2018 dataset and the dataset containing the national Lidar fly-by of Luxembourg. Based on visual inspection, the inferred super-resolution images exhibit particularly superior quality. In particular, the results for the high-resolution DFC2018 dataset are realistic and almost indistinguishable from the ground truth images.
title: Structural behaviour and design of grouted connections cast with neat seawater mixed OPC
Creators: name: Bartminn, Daniel
Publisher: name: Universität Kassel
Year: 2021
Subjects: subject: seawater mixed OPC
subject: grouted connection
subject: Offshore-wind
subject: jacket
subject: neat grout
subject: heat of hydration
subject: seawater durability
subject: ISO 19902 vs DIN EN 1992
subject: 624
subject: Offshorebauwerk
subject: Struktur
subject: Verwendung
subject: Portlandzement
subject: Mörtel
subject: Meerwasser

description: Zugleich: Dissertation, Universität Kassel, 2021
Carter-constant induced mechanism for generation of anisotropic kinetic equilibria in collisionless N-body systems
Creators: name: Cremaschini, Claudio
name: Stuchlík, Zdeněk
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: FOS: Physical sciences

description: A new intrinsically-relativistic kinetic mechanism for generation of non-isotropic relativistic kinetic equilibria in collisionless N-body systems is pointed out. The theory is developed in the framework of the covariant Vlasov statistical description. The new effect is based on the constraints placed by the conservation laws of neutral single-particle dynamics in prescribed background curved-spacetimes demonstrating existence of Killing tensors. As an illustration, the particular case of the Kerr space-time admitting the so-called Carter constant for the particle geodesic motion is considered. The general functional form of the equilibrium kinetic distribution function (KDF) is determined and an explicit realization in terms of Gaussian-like distributions is provided. It is shown that, due to the Carter constant, these equilibrium KDFs exhibit an anisotropic phase-space functional dependence in terms of the single-particle 4-velocity components, giving rise to corresponding non-isotropic continuum fluid fields. The qualitative properties of the equilibrium stress-energy tensor associated with these systems are discussed, with a particular emphasis on the related occurrence of temperature anisotropy effects. The theory is susceptible of astrophysical applications, including in particular the statistical properties of dark matter halos around stellar-mass or galactic-center black holes.
description: 14 pages
Dual Geometry of Entanglement Entropy via Deep Learning
Creators: name: Park, Chanyong
name: Hwang, Chi-Ok
name: Cho, Kyungchan
name: Kim, Se-Jin
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Mathematical Physics (math-ph)
subject: FOS: Physical sciences

description: For a given entanglement entropy of QFT, we investigate how to reconstruct its dual geometry by applying the Ryu-Takayanagi formula and the deep learning method. In the holographic setup, the radial direction of the dual geometry is identified with the energy scale of the dual QFT. Therefore, the holographic dual geometry can describe how the QFT changes along the RG flow. Intriguingly, we show that the reconstructed geometry only from the entanglement entropy data can give us more information about other physical properties like thermodynamic quantities in the IR region.
description: 17 pages, 9 figures
Kinetic equilibria of relativistic collisionless plasmas in the presence of non-stationary electromagnetic fields
Creators: name: Cremaschini, Claudio
name: Tessarotto, Massimo
name: Stuchlík, Zdeněk
Publisher: name: arXiv
Year: 2023
Subjects: subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: Statistical Mechanics (cond-mat.stat-mech)
subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: The kinetic description of relativistic plasmas in the presence of time-varying and spatially non-uniform electromagnetic fields is a fundamental theoretical issue both in astrophysics and plasma physics. This refers, in particular, to the treatment of collisionless and strongly-magnetized plasmas in the presence of intense radiation sources. In this paper the problem is investigated in the framework of a covariant gyrokinetic treatment for Vlasov-Maxwell equilibria. The existence of a new class of kinetic equilibria is pointed out, which occur for spatially-symmetric systems. These equilibria are shown to exist in the presence of non-uniform background EM fields and curved space-time. In the non-relativistic limit this feature permits the determination of kinetic equilibria even for plasmas in which particle energy is not conserved due to the occurrence of explicitly time-dependent EM fields. Finally, absolute stability criteria are established which apply in the case of infinitesimal symmetric perturbations that can be either externally or internally produced.
description: 8 pages
Sample Distortion for Compressed Imaging
Creators: name: Guo, Chunli
name: Davies, Mike E.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Information Theory (cs.IT)
subject: FOS: Computer and information sciences

description: We propose the notion of a sample distortion (SD) function for independent and identically distributed (i.i.d) compressive distributions to fundamentally quantify the achievable reconstruction performance of compressed sensing for certain encoder-decoder pairs at a given sampling ratio. Two lower bounds on the achievable performance and the intrinsic convexity property is derived. A zeroing procedure is then introduced to improve non convex SD functions. The SD framework is then applied to analyse compressed imaging with a multi-resolution statistical image model using both the generalized Gaussian distribution and the two-state Gaussian mixture distribution. We subsequently focus on the Gaussian encoder-Bayesian optimal approximate message passing (AMP) decoder pair, whose theoretical SD function is provided by the rigorous analysis of the AMP algorithm. Given the image statistics, analytic bandwise sample allocation for bandwise independent model is derived as a reverse water-filling scheme. Som and Schniter's turbo message passing approach is further deployed to integrate the bandwise sampling with the exploitation of the hidden Markov tree structure of wavelet coefficients. Natural image simulations confirm that with oracle image statistics, the SD function associated with the optimized sample allocation can accurately predict the possible compressed sensing gains. Finally, a general sample allocation profile based on average image statistics not only illustrates preferable performance but also makes the scheme practical.
description: 12 pages, 10 figures
title: Ευέλικτη  κατοικία : από την παραδοσιακή Ιαπωνική αρχιτεκτονική στην ελεύθερη κάτοψη, την πολλαπλότητα και τον σύγχρονο μετατρέψιμο χώρο
title: Flexible dwelling: from traditional Japanese architecture to open space, polyvalency and contemporary convertible space.
Creators: name: Μηλα Ζωη
Publisher: name: Technical University of Crete
Year: 2019

description: Βασικός σκοπός της εργασίας είναι η ανάλυση του όρου της ευελιξίας και η  ανάδειξη της διαχρονικής ανάγκης του ανθρώπου ο χώρος- κατοικία να μεταβάλλεται ανάλογα με τις υπάρχουσες συνθήκες. Καθώς επίσης και η συσχέτιση της παραδοσιακής ιαπωνικής αρχιτεκτονικής, που θα μπορούσε να χαρακτηριστεί ως αρχέτυπο, με την εξέλιξη της μοντέρνας αρχιτεκτονικής σε θέματα ευελιξίας. Αυτό επιτυγχάνεται με την ανάλυση του όρου της ευελιξίας, την παρουσίαση της ιαπωνικής φιλοσοφίας και αρχιτεκτονικής, την ανάδειξη της θεωρητικής σχέσης ανάμεσα στην ιαπωνική κουλτούρα και στο Μοντέρνο Κίνημα και τέλος με την διερεύνηση σύγχρονων αρχιτεκτόνων όπως ο Shigeru Ban. Ταυτόχρονα τονίζεται η αναγκαιότητα της ευελιξίας στην κατοικία στη σύγχρονη εποχή εξαιτίας των έντονων κοινωνικών αλλαγών που την χαρακτηρίζουν.
description: This paper presents a comprehensive review of the concepts of flexibility and human needs as well as the evolution of flexible housing structures over time. The main purpose of this essay is to highlight the constant need for change of our surroundings according to the existing conditions. This is especially true in the modern age when new social trends and rapid changes create new circumstances. Furthermore, the deep relationship between Japanese Culture and Flexibility is analyzed, which the representatives of the Modern Movement acknowledged and adopted. In addition, modern design techniques aiming at flexible structures, which were introduced by the Modern Movement and later on, are presented. These are: Open Space, Polyvalency, Indeterminacy, Incomplete Space, Redundant Space and Convertible Space. It is also considered how these terms are related to the structure of traditional Japanese house. Finally, the historical evolution of the flexible house with its Japanese references is examined regarding the Modern Movement, the Metabolist Movement and how it is presented in the works of contemporary architects with particular focus on Shigeru Ban.
Convergence of the nucleation rate for first-order phase transitions
Creators: name: Ekstedt, Andreas
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: This paper investigates the importance of radiative corrections for first-order phase transitions, with particular focus on the bubble-nucleation rate. All calculations are done with a strict power-counting, and observables are consistently calculated at every order. This ensures that physical quantities are gauge and renormalization-scale invariant. Furthermore, to avoid large logarithms at high-temperatures, an effective three-dimensional theory is used. This effective theory automatically incorporates higher-order thermal masses. The results of this paper indicate that sub-leading corrections to the rate can be large. This is partly because radiative corrections are enhanced for large bubbles. To illustrate the calculations, three models are considered: a real-scalar model, a radiative-barrier model, and a model with an effective dimension $6$ operator. Relevant observables are calculated for each model, and the reliability of perturbation theory is discussed.
description: 6 pages, 3 figures
Relieving String Tension By Making Baby Universes in a Dynamical String Tension Braneworld Model
Creators: name: Guendelman, Eduardo I.
name: Merali, Zeeya
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: FOS: Physical sciences

description: String tension fundamentally determines the properties of strings; yet its value is often assigned arbitrarily, creating a fine-tuning problem. We describe a mechanism for dynamically generating string tension in a flat or almost flat spacetime, using the modified measures formalism, which in turn naturally generates a new type of stringy brane-world scenario. Such a scenario allows strings to achieve near infinite tension confining the strings to two very close expanding surfaces, but the infinite tensions also threatens to distort the near-flat embedding spacetime through large back reactions. We argue that this danger can be neutralised via the creation of a baby universe, a growing region of emdedding spacetime that divorces from the ambient embedding spacetime, while our universe is still a brane separating two nearly flat spacetimes. The avoidance of a minimum length and a maximum Hagedorn temperature in the context of dynamical string tension generation are also discussed.
description: Honorable mention in the Gravity Research Foundation 2022 Essays on Gravitation Competition. arXiv admin note: substantial text overlap with arXiv:2202.10457, arXiv:2107.08005
Flux-controlled quantum computation with Majorana fermions
Creators: name: Hyart, T.
name: van Heck, B.
name: Fulga, I. C.
name: Burrello, M.
name: Akhmerov, A. R.
name: Beenakker, C. W. J.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Quantum Physics (quant-ph)
subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: FOS: Physical sciences

description: Majorana fermions hold promise for quantum computation, because their non-Abelian braiding statistics allows for topologically protected operations on quantum information. Topological qubits can be constructed from pairs of well-separated Majoranas in networks of nanowires. The coupling to a superconducting charge qubit in a transmission line resonator (transmon) permits braiding of Majoranas by external variation of magnetic fluxes. We show that readout operations can also be fully flux-controlled, without requiring microscopic control over tunnel couplings. We identify the minimal circuit that can perform the initialization--braiding--measurement steps required to demonstrate non-Abelian statistics. We introduce the Random Access Majorana Memory, a scalable circuit that can perform a joint parity measurement on Majoranas belonging to a selection of topological qubits. Such multi-qubit measurements allow for the efficient creation of highly entangled states and simplify quantum error correction protocols by avoiding the need for ancilla qubits.
description: Final version
Superconductivity of Ta-Hf and Ta-Zr alloys: Potential alloys for use in superconducting devices
Creators: name: Klimczuk, Tomasz
name: Królak, Szymon
name: Cava, Robert J.
Publisher: name: arXiv
Year: 2023
Subjects: subject: Superconductivity (cond-mat.supr-con)
subject: Materials Science (cond-mat.mtrl-sci)
subject: FOS: Physical sciences

description: The electronic properties relevant to the superconductivity are reported for bulk Ta-Hf and Ta-Zr body centered cubic alloys, in large part to determine whether their properties are suitable for potential use in superconducting qbits. The body centered cubic unit cell sizes increase with increasing alloying. The results of magnetic susceptibility, electrical resistivity and heat capacity characterization are reported. While elemental Ta is a type I superconductor, the alloys are type II strong coupling superconductors. Although decreasing the electron count per atom is expected to increase the density of electronic states at the Fermi level and thus the superconducting transition temperature (Tc) in these systems, we find that this is not sufficient to explain the significant increases in the superconducting Tc's observed.
On the classicality of bosonic stars
Creators: name: Herdeiro, Carlos A. R.
name: Radu, Eugen
Publisher: name: arXiv
Year: 2022
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: High Energy Physics - Theory (hep-th)
subject: FOS: Physical sciences

description: Because the Klein-Gordon and Proca equations involve $\hbar$, they describe quantum fields. Their solutions, however, may be treated as classical if their typical action obeys $S^{\rm typical}\gg \hbar$. This is possible due to their bosonic nature, allowing states with many particles. We show, by generic arguments, that the typical action for such bosonic stars is ${\mathcal{S}^{\rm typical}}/{\hbar}\gtrsim \left({M^{\rm max}}/{M_{\rm Pl}}\right)^2\sim 10^{76}\left({M^{\rm max}}/{M_\odot}\right)^2$, where $M^{\rm max}$ is the maximal bosonic star mass of the particular model and $M_{\rm Pl}$ is the Planck mass. Thus, for models allowing $M^{\rm max}\gg M_{\rm Pl}$ and for solutions with mass $\sim M^{\rm max}$, the classical treatment is legitimate, which includes masses in the astrophysical interesting range $\gtrsim M_\odot$.
description: 11 pages; Essay written for the Gravity Research Foundation 2022 Awards for Essays on Gravitation and selected for Honorable Mention
Open Geospatial Data: A comparison of data cultures in local government and the role of academic libraries
Creators: name: Majewicz, Karen
name: Martindale, Jaime
name: Kernik, Melinda
Publisher: name: Zenodo
Year: 2021

description: County and municipal governments are primary creators of foundational geospatial data, including essential layers such as parcels, road centerlines, address points, land use, and elevation. This data is aggregated into regionalized layers that make up state and national frameworks, and it is sought after by researchers for analysis and by cartographers to serve as base map layers. Despite the importance of these layers, policies about whether this data is free and open to the public varies from place to place. In most areas of the United States, counties and municipalities are not required to comply with federal rules or state initiatives for open data. As a result, some regions offer hundreds of open data layers to the public, while their neighbors may have zero, preferring to restrict the data due to privacy, economic, or accuracy concerns. The state of Wisconsin recently passed legislation requiring that certain foundational geospatial data created by counties must be made available to the public. By contrast, its neighboring state of Minnesota uses a voluntary approach that allows counties to choose for themselves if their geospatial data will be free and open. This paper compares the implications and outcomes of these diverging data cultures. We also advocate for the role that academic libraries can play to support the culture of practices around collection, documentation, and discoverability of local data, pointing to the Big Ten Academic Alliance Geoportal and GeoData@Wisconsin as examples.
Limits on Violations of Lorentz Symmetry and the Einstein Equivalence Principle using Radio-Frequency Spectroscopy of Atomic Dysprosium
Creators: name: Hohensee, M. A.
name: Leefer, N.
name: Budker, D.
name: Harabati, C.
name: Dzuba, V. A.
name: Flambaum, V. V.
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: Atomic Physics (physics.atom-ph)
subject: FOS: Physical sciences

description: We report a joint test of local Lorentz invariance and the Einstein equivalence principle for electrons, using long-term measurements of the transition frequency between two nearly degenerate states of atomic dysprosium. We present many-body calculations which demonstrate that the energy splitting of these states is particularly sensitive to violations of both special and general relativity. We limit Lorentz violation for electrons at the level of $10^{-17}$, matching or improving the best laboratory and astrophysical limits by up to a factor of 10, and improve bounds on gravitational redshift anomalies for electrons by 2 orders of magnitude, to $10^{-8}$. With some enhancements, our experiment may be sensitive to Lorentz violation at the level of $9\times 10^{-20}$.
description: Updated to match published version
Wang's B machines are efficiently universal, as is Hasenjaeger's small universal electromechanical toy
Creators: name: Neary, Turlough
name: Woods, Damien
name: Murphy, Niall
name: Glaschick, Rainer
Publisher: name: arXiv
Year: 2013
Subjects: subject: Computational Complexity (cs.CC)
subject: Data Structures and Algorithms (cs.DS)
subject: FOS: Computer and information sciences
subject: F.1.1
subject: 68Q05,

description: In the 1960's Gisbert Hasenjaeger built Turing Machines from electromechanical relays and uniselectors. Recently, Glaschick reverse engineered the program of one of these machines and found that it is a universal Turing machine. In fact, its program uses only four states and two symbols, making it a very small universal Turing machine. (The machine has three tapes and a number of other features that are important to keep in mind when comparing it to other small universal machines.) Hasenjaeger's machine simulates Hao Wang's B machines, which were proved universal by Wang. Unfortunately, Wang's original simulation algorithm suffers from an exponential slowdown when simulating Turing machines. Hence, via this simulation, Hasenjaeger's machine also has an exponential slowdown when simulating Turing machines. In this work, we give a new efficient simulation algorithm for Wang's B machines by showing that they simulate Turing machines with only a polynomial slowdown. As a second result, we find that Hasenjaeger's machine also efficiently simulates Turing machines in polynomial time. Thus, Hasenjaeger's machine is both small and fast. In another application of our result, we show that Hooper's small universal Turing machine simulates Turing machines in polynomial time, an exponential improvement.
description: 18 pages, 1 figure, 1 table, Conference: Turing in context II - History and Philosophy of Computing, 2012
Reconfigurable Intelligent Surface-Empowered MIMO Systems
Creators: name: Basar, Ertugrul
Publisher: name: arXiv
Year: 2023
Subjects: subject: Information Theory (cs.IT)
subject: Signal Processing (eess.SP)
subject: FOS: Computer and information sciences
subject: FOS: Electrical engineering, electronic engineering, information engineering

description: Reconfigurable intelligent surface (RIS)-empowered communication stands out as a solid candidate for future wireless networks due to its flexibility, ease of deployment, and attractive advantages to control the wireless propagation environment. In this perspective article, a brief overview is presented considering the application of reconfigurable intelligent surfaces for future multiple-input multiple-output (MIMO) systems. Potential future research directions are also highlighted.
description: 4 pages, to appear in National Science Review
Alternatives to a nonhomogeneous partial differential equation quantum algorithm
Creators: name: Ricardo, Alexandre C.
name: Fernandes, Gabriel P. L. M.
name: Duzzioni, Eduardo I.
name: Campo, Vivaldo L.
name: Villas-Bôas, Celso J.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Quantum Physics (quant-ph)
subject: FOS: Physical sciences

description: Recently J. M. Arrazola et al. [Phys. Rev. A 100, 032306 (2019)] proposed a quantum algorithm for solving nonhomogeneous linear partial differential equations of the form $Aψ(\textbf{r})=f(\textbf{r})$. Its nonhomogeneous solution is obtained by inverting the operator $A$ along with the preparation and measurement of special ancillary modes. In this work we suggest modifications in its structure to reduce the costs of preparing the initial ancillary states and improve the precision of the algorithm for a specific set of inputs. These achievements enable easier experimental implementation of the quantum algorithm based on nowadays technology.
description: 10 pages, 8 figures
Photoacoustic Tomography using a Michelson Interferometer with Quadrature Phase Detection
Creators: name: Speirs, Rory W.
name: Bishop, Alexis I.
Publisher: name: arXiv
Year: 2013
Subjects: subject: Optics (physics.optics)
subject: FOS: Physical sciences

description: We present a pressure sensor based on a Michelson interferometer, for use in photoacoustic tomography. Quadrature phase detection is employed allowing measurement at any point on the mirror surface without having to retune the interferometer, as is typically required by Fabry-Perot type detectors. This opens the door to rapid full surface detection, which is necessary for clinical applications. Theory relating acoustic pressure to detected acoustic particle displacements is used to calculate the detector sensitivity, which is validated with measurement. Proof-of-concept tomographic images of blood vessel phantoms have been taken with sub-millimeter resolution at depths of several millimeters.
description: Copyright 2013 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Applied Physics Letters, Volume 103, Issue 5, Page 053501, (2013) and may be found at http://link.aip.org/link/doi/10.1063/1.4816427
title: Διαχείριση χωροχρονικής πληροφορίας σε εφαρμογές σημασιολογικού ιστού
Creators: name: Χατζηγεωργακίδης Γεώργιος
Publisher: name: Technical University of Crete
Year: 2011

description: Μη διαθέσιμο
Post-Keplerian waveform model for binary compact object as sources of space-based gravitational wave detector and its implications
Creators: name: Li, Li-Fang
name: Cao, Zhoujian
Publisher: name: arXiv
Year: 2023
Subjects: subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Astrophysical Phenomena (astro-ph.HE)
subject: FOS: Physical sciences

description: Binary compact objects will be among the important sources for the future space-based gravitational wave detectors. Such binary compact objects include stellar massive binary black hole, binary neutron star, binary white dwarf and mixture of these compact objects. Regarding to the relatively low frequency, the gravitational interaction between the two objects of the binary is weak. Post-Newtonian approximation of general relativity is valid. Previous works about the waveform model for such binaries in the literature consider the dynamics for specific situations which involve detailed complicated matter dynamics between the two objects. We here take a different idea. We adopt the trick used in pulsar timing detection. For any gravity theories and any detailed complicated matter dynamics, the motion of the binary can always be described as a post-Keplerian expansion. And a post-Keplerian gravitational waveform model will be reduced. Instead of object masses, spins, matter's equation of state parameters and dynamical parameters beyond general relativity, the involved parameters in our post-Keplerian waveform model are the Keplerian orbit elements and their adiabatic variations. Respect to current planning space-based gravitational wave detectors including LISA, Taiji and Tianqin, we find that the involved waveform model parameters can be well determined. And consequently the detail matter dynamics of the binary can be studied then. For binary with purely gravitational interactions, gravity theory can be constrained well.
description: 14 pages, 3 figures
Proper Motions, Orbits, and Tidal Influences of Milky Way Dwarf Spheroidal Galaxies
Creators: name: Pace, Andrew B.
name: Erkal, Denis
name: Li, Ting S.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Astrophysics of Galaxies (astro-ph.GA)
subject: FOS: Physical sciences

description: We combine Gaia EDR3 astrometry with accurate photometry and utilize a probabilistic mixture model to measure the systemic proper motion of 52 dwarf spheroidal (dSph) satellite galaxies of the Milky Way (MW). For the 46 dSphs with literature line-of-sight velocities we compute orbits in both a MW and a combined MW + Large Magellanic Cloud (LMC) potential and identify Car II, Car III, Hor I, Hyi I, Phx II, and Ret II as likely LMC satellites. 40% of our dSph sample has a >25% change in pericenter and/or apocenter with the MW + LMC potential. For these orbits, we Monte Carlo sample over the observational uncertainties for each dSph and the uncertainties in the MW and LMC potentials. We predict that Ant II, Boo III, Cra II, Gru II, and Tuc III should be be tidally disrupting by comparing each dSph's average density relative to the MW density at its pericenter. dSphs with large ellipticity (CVn I, Her, Tuc V, UMa I, UMa II, UMi, Wil 1) show a preference for their orbital direction to align with their major axis even for dSphs with large pericenters. We compare the dSph radial orbital phase to subhalos in MW-like N-body simulations and infer that there is not an excess of satellites near their pericenter. With projections of future Gaia data releases, we find dSph orbital precision will be limited by uncertainties in the distance and/or MW potential rather than proper motion precision. Finally, we provide our membership catalogs to enable community follow-up.
description: 26 pages, 13 figures + appendix with extra figures. ApJ accepted. Catalogs with membership, additional figures, and a machine readable compilation of tables 1-4 are available at https://zenodo.org/record/6533295
Tunnel conductance spectroscopy via harmonic generation in a hybrid capacitor device
Creators: name: Appelbaum, Ian
Publisher: name: arXiv
Year: 2013
Subjects: subject: Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
subject: Superconductivity (cond-mat.supr-con)
subject: FOS: Physical sciences

description: We address the measurement of density of states within and beyond the superconducting gap in tunnel-coupled finite-size nanostructures using a capacitive method. Third-harmonic generation is used to yield the full differential conductance spectrum without destruction of the low dimensionality otherwise induced by intimate ohmic coupling to an electrode. The method is particularly relevant to attempts to discern the presence of the fragile Majorana quasiparticle at the end of spin-orbit-coupled nanowires in appropriate magnetic field conditions by their signature mid-gap density of states.
description: letter format
Emergent Early Universe Cosmology from BFSS Matrix Theory
Creators: name: Brahma, Suddhasattwa
name: Brandenberger, Robert
name: Laliberte, Samuel
Publisher: name: arXiv
Year: 2022
Subjects: subject: High Energy Physics - Theory (hep-th)
subject: Cosmology and Nongalactic Astrophysics (astro-ph.CO)
subject: General Relativity and Quantum Cosmology (gr-qc)
subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The BFSS matrix model is a suggested non-perturbative definition of string theory. Starting from a thermal state of this matrix model, we show how space and time can emerge dynamically. Results from the IKKT matrix model indicate that the $SO(9)$ symmetry of space is spontaneously broken to $SO(3) \times SO(6)$, with the three-dimensional subspace becoming large. Given this initial state for the universe, we show that cosmological perturbations and gravitational waves with scale-invariant spectra are generated, without the need of postulating an early phase of cosmological inflation. The Big Bang singularity is automatically resolved.
description: Essay written for the Gravity Research Foundation 2022 Awards for Essays on Gravitation, honorary mention, 10 pages, 1 figure
The universal enveloping algebra of the Witt algebra is not noetherian
Creators: name: Sierra, Susan J.
name: Walton, Chelsea
Publisher: name: arXiv
Year: 2013
Subjects: subject: Rings and Algebras (math.RA)
subject: Algebraic Geometry (math.AG)
subject: FOS: Mathematics

description: This work is prompted by the long standing question of whether it is possible for the universal enveloping algebra of an infinite dimensional Lie algebra to be noetherian. To address this problem, we answer a 23-year-old question of Carolyn Dean and Lance Small; namely, we prove that the universal enveloping algebra of the Witt (or centerless Virasoro) algebra is not noetherian. To show this, we prove our main result: the universal enveloping algebra of the positive part of the Witt algebra is not noetherian. We employ algebro-geometric techniques from the first author's classification of (noncommutative) birationally commutative projective surfaces. As a consequence of our main result, we also show that the enveloping algebras of many other infinite dimensional Lie algebras are not noetherian. These Lie algebras include the Virasoro algebra and all infinite dimensional Z-graded simple Lie algebras of polynomial growth.
Design of plasma shutters for improved heavy ion acceleration by ultra-intense laser pulses
Creators: name: Matys, M.
name: Bulanov, S. V.
name: Kucharik, M.
name: Jirka, M.
name: Nikl, J.
name: Kecova, M.
name: Proska, J.
name: Psikal, J.
name: Korn, G.
name: Klimo, O.
Publisher: name: arXiv
Year: 2022
Subjects: subject: Plasma Physics (physics.plasm-ph)
subject: FOS: Physical sciences

description: In this work, we investigate the application of the plasma shutters for heavy ion acceleration driven by a high-intensity laser pulse. We use particle-in-cell (PIC) and hydrodynamic simulations. The laser pulse, transmitted through the opaque shutter, gains a steep-rising front and its peak intensity is locally increased at the cost of losing part of its energy. These effects have a direct influence on subsequent ion acceleration from the ultrathin target behind the shutter. In our 3D simulations of silicon nitride plasma shutter and a silver target, the maximal energy of high-Z ions increases significantly when the shutter is included for both linearly and circularly polarized laser pulses. Moreover, application of the plasma shutter for linearly polarized pulse results in focusing of ions towards the laser axis in the plane perpendicular to the laser polarization. The generated high energy ion beam has significantly lower divergence compared to the broad ion cloud, generated without the shutter. The effects of prepulses are also investigated assuming a double plasma shutter. The first shutter can withstand the assumed sub-ns prepulse (treatment of ns and ps prepulses by other techniques is assumed) and the pulse shaping occursvia interaction with the second shutter. On the basis of our theoretical findings, we formulated an approach towards designing a double plasma shutter for high-intensity and high-power laser pulses and built a prototype.
description: 30 pages 13 figures
title: Ανάπτυξη συστήματος MPPT για φωτοβολταϊκές συστοιχίες που λειτουργούν σε συνθήκες μερικής σκίασης
Creators: name: Καλογιαννάκης Ιωάννης
Publisher: name: Technical University of Crete
Year: 2011

description: Μη διαθέσιμο
Documenting Variable Comparability with DDI-Lifecycle
Creators: name: Lavender, Kathryn
name: Ionescu, Sanda
Publisher: name: Zenodo
Year: 2021

description: ICPSR has recently been actively engaged in moving to DDI-Lifecycle to document some of its longitudinal data. Pilot projects involving the creation of DDI-L metadata for two of our most popular longitudinal studies have already been finalized, and the variable-level documentation for the National Social Life, Health, and Aging Project (NSHAP) is now publicly available for online searching and exploring comparability across waves. Using this previous work as a background, we will focus our presentation on a new, ongoing project that uses DDI-Lifecycle to document comparability between two independent longitudinal collections – the NSHAP and the National Health and Aging Study (NHATS) - that explore similar topics, with special focus on health and cognition issues among aging populations. We will elaborate on the steps, the tools we used, and the decisions taken to move this project forward, and will share practical details regarding its organization and progress. We will also include our findings regarding potential difficulties and benefits.
title: Υλοποίηση σε αναδιατασσόμενη λογική των πινάκων ουράνιου τόξου (rainbow tables) για την αποκρυπτογράφηση του κρυπτογραφικού αλγόριθμου Α5/3 που χρησιμοποιείται σε δίκτυα 3ης γενιάς (3G)
Creators: name: Παπαντωνάκης Παναγιώτης
Publisher: name: Technical University of Crete
Year: 2011

description: Μη διαθέσιμο
Gravitino dark matter production at finite temperature
Creators: name: Dalianis, Iannis
Publisher: name: arXiv
Year: 2013
Subjects: subject: High Energy Physics - Phenomenology (hep-ph)
subject: FOS: Physical sciences

description: The production and the final abundance of gravitino dark matter appear to depend crucially on the restoration of the global U(1) $R$-symmetry of GMSB sectors in a threefold way. An $R$-symmetric phase effectively suppresses the production of goldstinos from scatterings with the supersymmetric Standard Model particles and it generically initiates the goldstino production from the thermalized messenger particles. In addition, the GMSB spurion gets displaced from the zero temperature minimum and under certain conditions it dominates the energy density of the universe producing late entropy. We show that it is possible to have high enough reheating temperatures that thermal leptogenesis and thermal vacuum selection can be realized without gravitino overproduction. The gravitino dark matter can be produced either thermally or non-thermally. In the former case the messenger scale has to be less than about $10^6$ GeV with the gravitino relatively heavy, $m_{3/2}\geq {\cal O}(10)$ GeV. In the later case, the gravitino is generically produced by the decay of the GMSB spurion field a process that always takes place for large messenger scales. A connection of our results with current collider and observational data is performed.
description: 33 pages, 8 figures, plain text, version accepted by JHEP, slightly shorter version, results unchanged
Generation of Radiology Findings in Chest X-Ray by Leveraging Collaborative Knowledge
Creators: name: Danu, Manuela Daniela
name: Marica, George
name: Karn, Sanjeev Kumar
name: Georgescu, Bogdan
name: Mansoor, Awais
name: Ghesu, Florin
name: Itu, Lucian Mihai
name: Suciu, Constantin
name: Grbic, Sasa
name: Farri, Oladimeji
name: Comaniciu, Dorin
Publisher: name: arXiv
Year: 2023
Subjects: subject: Computer Vision and Pattern Recognition (cs.CV)
subject: Computation and Language (cs.CL)
subject: FOS: Computer and information sciences

description: Among all the sub-sections in a typical radiology report, the Clinical Indications, Findings, and Impression often reflect important details about the health status of a patient. The information included in Impression is also often covered in Findings. While Findings and Impression can be deduced by inspecting the image, Clinical Indications often require additional context. The cognitive task of interpreting medical images remains the most critical and often time-consuming step in the radiology workflow. Instead of generating an end-to-end radiology report, in this paper, we focus on generating the Findings from automated interpretation of medical images, specifically chest X-rays (CXRs). Thus, this work focuses on reducing the workload of radiologists who spend most of their time either writing or narrating the Findings. Unlike past research, which addresses radiology report generation as a single-step image captioning task, we have further taken into consideration the complexity of interpreting CXR images and propose a two-step approach: (a) detecting the regions with abnormalities in the image, and (b) generating relevant text for regions with abnormalities by employing a generative large language model (LLM). This two-step approach introduces a layer of interpretability and aligns the framework with the systematic reasoning that radiologists use when reviewing a CXR.
description: Information Technology and Quantitative Management (ITQM 2023)