Now showing items 1-20 of 409

    • One-parameter Darboux-transformed quantum actions in thermodynamics 

      Rosu Barbus, Haret-Codratian; Aceves de la Cruz, Fermín (2002)
      "We use nonrelativistic supersymmetry, mainly Darboux transformations of the general (one-parameter) type, for the quantum oscillator thermodynamic actions. Interesting Darboux generalizations of the fundamental Planck and ...
    • Gravitational bouncing of a quantum ball: Room for Airy's function Bi 

      Rosu Barbus, Haret-Codratian (2002)
      "I apply (i) a classical version of the Ermakov-Lewis procedure and (ii) the strictly isospectral supersymmetric approach to the Schrodinger free fall of the bouncing ball type. In both cases, the Airy function Bi, which ...
    • Newton´s laws of motion in the form of a Riccati equation 

      Marek Nowakowski; Rosu Barbus, Haret-Codratian (2002)
      "We discuss two applications of a Riccati equation to Newton´s laws of motion. The first one is the motion of a particle under the influence of a power law central potential V(r)=krε. For zero total energy we show that the ...
    • On arithmetic detection of grey pulses with application to Hawking radiation 

      Rosu Barbus, Haret-Codratian; Michel Planat (2002)
      "Micron-sized black holes do not necessarily have a constant horizon temperature distribution. The black hole remote-sensing problem means to find out the "surface" temperature distribution of a small black hole from the ...
    • KdV adiabatic index solitons in barotropic open FRW cosmologies 

      Rosu Barbus, Haret-Codratian (2002)
      "Applying standard mathematical methods, it is explicitly shown how the Riccati equation for the Hubble parameter H() of barotropic open FRW cosmologies is connected with a Korteweg-de Vries equation for adiabatic index ...
    • Ramanujan sums for signal processing of low-frequency noise 

      Michel Planat; Rosu Barbus, Haret-Codratian; Serge Perrine (2002)
      "An aperiodic (low-frequency) spectrum may originate from the error term in the mean value of an arithmetical function such as Mobius function or Mangoldt function, which are coding sequences for prime numbers. In the ...
    • Aristotle: the first encyclopedist 

      Rosu Barbus, Haret-Codratian (2002)
      "Aristotle was the first to declare himself in the class of natural philosophers (physiologoi) and he was the first physicist because he spelled out the first definitions of some basic physical concepts. Moreover, he was ...
    • Transform of Riccati equation of constant coefficients through fractional procedure 

      Rosu Barbus, Haret-Codratian; L. Madueno; García Díaz, José Socorro (2003)
      "We use a particular fractional generalization of the ordinary differential equations that we apply to the Riccati equation of constant coefficients. By this means the latter is transformed into a modified Riccati equation ...
    • One-parameter nonrelativistic supersymmetry for microtubules 

      Rosu Barbus, Haret-Codratian; Cornejo Pérez, Octavio (2003)
      "The one-parameter nonrelativistic supersymmetry of Mielnik [J. Math. Phys. 25, 3387 (1984)] is applied to the simple supersymmetric model of Caticha [Phys. Rev. A 51, 4264 (1995)] in the form used by Rosu [Phys. Rev. E ...
    • Cyclotomy and Ramanujan sums in quantum phase locking 

      Michel Planat; Rosu Barbus, Haret-Codratian (2003)
      "Phase-locking governs the phase noise in classical clocks through effects described in precise mathematical terms. We seek here a quantum counterpart of these effects by working in a finite Hilbert space. We use a coprimality ...
    • Words for nobel prizes 

      Rosu Barbus, Haret-Codratian (2003)
      "We present the statistics of the significant nouns and adjectives of social impact figuring in the nominations of the Nobel prizes in Physics and Chemistry over the period of the awards from 1901 to 2001."
    • Quantum Hamiltonians and prime numbers 

      Rosu Barbus, Haret-Codratian (2003)
      "A short review of Schrödinger Hamiltonian for which the spectral problem has beenVrelated in the literature to the distribution of the prime numbers is presented here. WeVnotice a possible connection between prime numbers ...
    • One-parameter isospectral special functions 

      Rosu Barbus, Haret-Codratian (2003)
      "Using a combination of the ladder operators of Pina [1] and the Pammetric operators of Mielnik [2] we introduce second order linear differential equations whose eigenfunctions are isospectral to the special functions of ...
    • Linear second-order differential equations for barotropic FRW cosmologies 

      Rosu Barbus, Haret-Codratian; Cornejo Pérez, Octavio (2003)
      "Simple linear second-order differential equations have been written down for FRW cosmologies with barotropic fluids by Faraoni. His results have been extended by Rosu, who employed techniques belonging to nonrelativistic ...
    • Transitional behaviour in the transformation from active end planes to stable loops caused by annealing 

      Endo, Morinobu; Lee, Byoung-Ju; Kim, Yoong Ahm; Kim, Yong-jung; Muramatsu, Hiroyuki; Yanagisawa, Takahashi; Hayashi, Takuya; Terrones Maldonado, Mauricio; Dresselhaus Mildred (IOP Publishing, 2003)
      "Here we investigate the stabilization process on the active outer/inner surfaces (or the end plane of a graphene sheet) for shortened cup-stacked-type carbon nanotubes caused by annealing, utilizing both analytic and ...
    • Theoretical characterization of several models of nanoporous carbon 

      Valencia Hernández, Felipe; Romero Castro, Aldo Humberto; Hernandez, Eduardo R.; Terrones Maldonado, Mauricio; Terrones Maldonado, Humberto (IOP Publishing, 2003)
      "Elastic, electronic and vibrational properties of seven models of nanoporous carbon are reported. The studied structures are periodic graphitic arrangements with heptagonal and octagonal rings of carbon, known ...
    • Curved nanostructured materials 

      Terrones Maldonado, Humberto; Terrones Maldonado, Mauricio (IOP Publishing, 2003)
      "Graphite is a layered material that is very flexible, in which each layer is able to curve in order to form cages, nanotubes, nanocoils, nanocones, etc. In this paper, we demonstrate that various synthetic routes are ...
    • Sistemas finitos bajo presión 

      Baltazar Rojas, Samuel Eleazar (2004)
      "El estudio de estructuras bajo condiciones extremas como altas presiones, pueden entregarnos nuevas configuraciones y/o situaciones que son metaestables bajo condiciones normales. Estas transiciones pueden estar asociadas ...
    • Classical harmonic oscillator with Dirac-like parameters and possible applications 

      Rosu Barbus, Haret-Codratian; Cornejo Pérez, Octavio; López Sandoval, Román (2004)
      "We obtain a class of parametric oscillation modes that we call K-modes with damping and absorption that are connected to the classical harmonic oscillator modes through the “supersymmetric” one-dimensional matrix procedure ...
    • The hyperbolic, the arithmetic and the quantum phase 

      Metod Saniga; Michel Planat; Rosu Barbus, Haret-Codratian (2004)
      "We develop a new approach of the quantum phase in an Hilbert space of finite dimension which is based on the relation between the physical concept of phase locking and mathematical concepts such as cyclotomy and the ...