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Year 2016
  • Crystallization of space: Space-time fractals from fractal arithmetic
    Publication

    Fractals such as the Cantor set can be equipped with intrinsic arithmetic operations (addition, subtraction, multiplication, division) that map the fractal into itself. The arithmetics allows one to define calculus and algebra intrinsic to the fractal in question, and one can formulate classical and quantum physics within the fractal set. In particular, fractals in space-time can be generated by means of homogeneous spaces associated...

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  • Do positrons measure atomic and molecular diameters?
    Publication

    - EUROPEAN PHYSICAL JOURNAL D - Year 2016

    We report on density functional calculations (DFT) of elastic integral scattering cross-sections for positron collisions with argon, krypton, nitrogen and methane. The long-range asymptotic polarization potential is described using higher-order terms going much beyond an induced dipole potential (−α / r 4) while the short-range interaction is modeled by two different forms of electron – positron correlation potential (Boroński-Nieminen...

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  • Electronic state spectroscopy by high-resolution vacuum ultraviolet photoabsorption, He(I) photoelectron spectroscopy and ab initio calculations of ethyl acetate
    Publication

    - EUROPEAN PHYSICAL JOURNAL D - Year 2016

    The high-resolution vacuum ultraviolet photoabsorption spectrum of ethyl acetate, C4H8O2, is presented over the energy range 4.5−10.7 eV (275.5−116.0 nm). Valence and Rydberg transitions and their associated vibronic series observed in the photoabsorption spectrum, have been assigned in accordance with new ab initio calculations of the vertical excitation energies and oscillator strengths. Also, the photoabsorption cross sections...

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  • Excitation energy transfer in partly ordered polymer films differing in donor and acceptor transition moments orientation
    Publication
    • A. Synak
    • P. Bojarski
    • M. Sadownik
    • L. Kułak
    • I. Gryczyński
    • B. Grobelna
    • S. Rangełowa-Jankowska
    • D. Jankowski
    • A. Kubicki

    - OPTICAL MATERIALS - Year 2016

    Based on spectroscopic measurements selected properties of nonradiative Förster energy transport are studied in uniaxially stretched polyvinyl alcohol thin films for three systems differing in donor and acceptor transition moments orientation relative to the axis of stretching. In particular, donor – acceptor emission anisotropy spectra yield completely different regularities for these systems in uniaxially stretched films, whereas...

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  • Fourier transforms on Cantor sets: A study in non-Diophantine arithmetic and calculus
    Publication

    Fractals equipped with intrinsic arithmetic lead to a natural definition of differentiation, integration, and complex structure. Applying the formalism to the problem of a Fourier transform on fractals we show that the resulting transform has all the required basic properties. As an example we discuss a sawtooth signal on the ternary middle-third Cantor set. The formalism works also for fractals that are not self-similar.

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  • Influence of Protonation State on the Excited State Dynamics of a Photobiologically Active Ru(II) Dyad
    Publication
    • C. Reichardt
    • T. Sainuddin
    • M. WäCHTLER
    • S. Monro
    • S. Kupfer
    • J. Guthmuller
    • S. Gräfe
    • S. A. Mcfarland
    • B. Dietzek

    - JOURNAL OF PHYSICAL CHEMISTRY A - Year 2016

    The influence of ligand protonation on the photophysics of a ruthenium (Ru) dyad bearing the 2-(1-pyrenyl)-1H-imidazo[4,5-f][1,10]-phenanthroline (ippy) ligand was investigated by time-resolved transient absorption spectroscopy. It was found that changes in the protonation state of the imidazole group led to changes in the electronic configuration of the lowest lying excited state. Formation of the fully deprotonated imidazole...

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  • Interactions of positrons with atoms and molecules
    Publication

    - Year 2016

    The positron is the antiparticle of the electron. It has the same mass as the electron, but opposite charge. The understanding of the interactions of positrons with normal matter, like atoms and molecules, is of interest in various scientific fields, like nuclear medicine, plasma physics and astronomy. In this talk we will give a short introduction to some theoretical methods to describe the interactions of positrons with atoms...

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  • Linear game non-contextuality and Bell inequalities—a graph-theoretic approach
    Publication

    - NEW JOURNAL OF PHYSICS - Year 2016

    We study the classical and quantum values of a class of one-and two-party unique games, that generalizes the well-known XOR games to the case of non-binary outcomes. In the bipartite case the generalized XOR(XOR-d) games we study are a subclass of the well-known linear games. We introduce a 'constraint graph' associated to such a game, with the constraints defining the game represented by an edge-coloring of the graph. We use the...

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  • No Quantum Realization of Extremal No-Signaling Boxes
    Publication

    - PHYSICAL REVIEW LETTERS - Year 2016

    The study of quantum correlations is important for fundamental reasons as well as for quantum communication and information processing tasks. On the one hand, it is of tremendous interest to derive the correlations produced by measurements on separated composite quantum systems from within the set of all correlations obeying the no-signaling principle of relativity, by means of information-theoretic principles. On the other hand,...

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  • NON-STATIONARY THERMAL SELF-ACTION OF ACOUSTIC BEAMS CONTAINING SHOCK FRONTS IN THERMOCONDUCTING FLUID
    Publication

    Non-stationary thermal self-action of a periodic or impulse acoustic beam containing shock fronts in a thermoconducting Newtonian fluid is studied. Self-focusing of a saw-tooth periodic and impulse sound is considered, as well as that of a solitary shock wave which propagates with the linear sound speed. The governing equations of the beam radius are derived. Numerical simulations reveal that the thermal conductivity weakens the...

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  • On the Nonlinea Distortions of Sound and its Coupling with Other Modes in a Gasesous Plasma with Finite Electric Conductivity in a Magnetic Field
    Publication

    Nonlinear phenomena of the planar and quasi-planar magnetoacoustic waves are considered. We focus on deriving of equations which govern nonlinear excitation of the non-wave motions by the intense sound in initially static gaseous plasma. The plasma is treated as an ideal gas with finite electrical conductivity permeated by a magnetic field orthogonal to the trajectories of gas particles. This introduces dispersion of a flow. Magnetoacoustic...

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  • On the Nonlinear Effects of Magnetoacoustic Perturbations in a Perfectly Conducting Viscous and Thermoconducting Gas
    Publication

    Nonlinear effects of planar and quasi-planar magnetosound perturbations are discussed. The plasma is as- sumed to be a Newtonian thermoconducting gas with infinite electrical conductivity permeated by a magnetic field orthogonal to the trajectories of gas particles. Generation of the non-wave modes (magnetoacoustic heating and streaming) in the field of periodic and aperiodic magnetoacoustic perturbations is discussed. The results...

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  • Quantum communication complexity advantage implies violation of a Bell inequality
    Publication

    - PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA - Year 2016

    We obtain a general connection between a quantum advantage in communication complexity and non-locality. We show that given any protocol offering a (sufficiently large) quantum advantage in communication complexity, there exists a way of obtaining measurement statistics which violate some Bell inequality. Our main tool is port-based teleportation. If the gap between quantum and classical communication complexity can grow arbitrarily...

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  • Randomness Amplification under Minimal Fundamental Assumptions on the Devices
    Publication
    • R. Ramanathan
    • F. Brandão
    • K. Horodecki
    • M. Horodecki
    • P. Horodecki
    • H. Wojewódka

    - PHYSICAL REVIEW LETTERS - Year 2016

    Recently, the physically realistic protocol amplifying the randomness of Santha-Vazirani sources producing cryptographically secure random bits was proposed; however, for reasons of practical relevance, the crucial question remained open regarding whether this can be accomplished under the minimal conditions necessary for the task. Namely, is it possible to achieve randomness amplification using only two no-signaling components...

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  • Realistic noise-tolerant randomness amplification using finite number of devices
    Publication
    • F. Brandão
    • R. Ramanathan
    • A. Grudka
    • K. Horodecki
    • M. Horodecki
    • P. Horodecki
    • T. Szarek
    • H. Wojewódka

    - Nature Communications - Year 2016

    Randomness is a fundamental concept, with implications from security of modern data systems, to fundamental laws of nature and even the philosophy of science. Randomness is called certified if it describes events that cannot be pre-determined by an external adversary. It is known that weak certified randomness can be amplified to nearly ideal randomness using quantum-mechanical systems. However, so far, it was unclear whether randomness amplification...

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  • Relativity of arithmetic as a fundamental symmetry of physics

    Arithmetic operations can be defined in various ways, even if one assumes commutativity and associativity of addition and multiplication, and distributivity of multiplication with respect to addition. In consequence, whenever one encounters ‘plus’ or ‘times’ one has certain freedom of interpreting this operation. This leads to some freedom in definitions of derivatives, integrals and, thus, practically all equations occurring in...

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  • Sharp transitions in low-number quantum dots Bayesian magnetometry
    Publication

    - Scientific Reports - Year 2016

    We consider Bayesian estimate of static magnetic field, characterized by a prior Gaussian probability distribution, in systems of a few electron quantum dot spins interacting with infinite temperature spin environment via hyperfine interaction. Sudden transitions among optimal states and measurements are observed. Usefulness of measuring occupation levels is shown for all times of the evolution, together with the role of entanglement...

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  • Standing Waves in a Rectangular Resonator Containing Acoustically Active Gases
    Publication

    The distribution of perturbations of pressure and velocity in a rectangular resonator is considered. A resonator contains a gas where thermodynamic processes take place, such as exothermic chemical reaction or excitation of vibrational degrees of a molecule’s freedom. These processes make the gas acoustically active under some conditions. We conclude that the incident and reflected compounds of a sound beam do not interact in the...

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  • Synthesis and characterization of ruthenium and rhenium dyes with phosphonate anchoring groups
    Publication

    - DALTON TRANSACTIONS - Year 2016

    Re(L1)–Re(L3), a series of rhenium(I) tricarbonyl chloride complexes with bpy-R2 derivatives L1–L3 (bpy = 2,2′-bipyridine, R represents the substitution at the 4- and 4′-positions), and their corresponding trishomoleptic Ru(L1)3–Ru(L3)3 as well as heteroleptic ruthenium(II) complexes Ru(tbbpy)2(L1) and Ru(tbbpy)2(L2) have been synthesized and characterized. Their applicability as immobilizable metal–organic chromophores in solar...

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  • The symmetric extendibility of quantum states

    Studies on the symmetric extendibility of quantum states have become particularly important in the context of the analysis of one-way quantum measures of entanglement, and the distillability and security of quantum protocols. In this paper we analyze composite systems containing a symmetric extendible part, with particular attention devoted to the one-way security of such systems. Further, we introduce a new one-way entanglement...

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  • Wavepacket of the Universe and its Spreading
    Publication

    Wavepackets in quantum mechanics spread and the Universe in cosmology expands. We discuss a formalism where the two effects can be unified. The basic assumption is that the Universe is determined by a unitarily evolving wavepacket defined on space-time. Space-time is static but the Universe is dynamic. Spreading analogous to expansion known from observational cosmology is obtained if one regards time evolution as a dynamical process...

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  • π-Stacking attraction vs. electrostatic repulsion: competing supramolecular interactions in a tpphz-bridged Ru(ii)/Au(iii) complex
    Publication
    • D. Sorsche
    • M. Schaub
    • F. Heinemann
    • J. Habermehl
    • S. Kuhri
    • D. Guldi
    • J. Guthmuller
    • S. Rau

    - DALTON TRANSACTIONS - Year 2016

    The synthesis and characterization of a mixed metal ruthenium(II)/gold(III) complex bridged by tetrapyridophenazine (tpphz) are described. It is isostructural and isoelectronic to the well-known photocatalysts with palladium(II) or platinum(II). Concentration dependent 1H-NMR spectroscopy and XRD studies show that the electrostatic repulsion between the gold(III) moieties exceeds the attractive π-stacking interaction. Theoretical...

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