Scientific Commons: Jan Myrheim

Physics © Springer-Verlag 1989 Complex Universality (2009)

Abstract. The theory of period doublings for one-parameter families of iterated real mappings is generalized to period n-tuplings for complex mappings. An n-tupling occurs when the eigenvalue of a...

Beam Scraping in the SPS for LHC Injection - Efficiency and Robustness Studies (2008)

Letnes, Paul/LPA, Burkhardt, Helmut, Myrheim, Jan

The Large Hadron Collider (LHC) at CERN will be the world's most powerful accelerator when it is commissioned in fall 2008. Operation of the LHC will require injection of very high intensity beams....

Extreme points of the set of density matrices with positive partial transpose (2007)

Leinaas, Jon Magne, Myrheim, Jan, Ovrum, Eirik

We present a necessary and sufficient condition for a finite dimensional density matrix to be an extreme point of the convex set of density matrices with positive partial transpose with respect to a...

Geometrical aspects of entanglement (2006)

Leinaas, Jon Magne, Myrheim, Jan, Ovrum, Eirik

We study geometrical aspects of entanglement, with the Hilbert--Schmidt norm defining the metric on the set of density matrices. We focus first on the simplest case of two two-level systems and show...

5 GeV/c differential cross-sections for $\pi^{\pm} p \to \pi^{\pm} p, K^{\pm} p \to K^{\pm}p, \overline{p}p\to \overline{p}p, \overline{p}p\to \pi^{+}\pi^{-}$, and $\overline{p}p \to K^{+} K^{-}$ (2006)

Chabaud, V, Eide, A, Lehmann, P, Lundby, Arne, Mukhin, S, Myrheim, Jan, ...

A tensor product matrix approximation problem in quantum physics (2006)

Dahl, Geir, Leinaas, Jon Magne, Myrheim, Jan, Ovrum, Eirik

Quantum Mechanics of a Particle with Two Magnetic Impurities (2005)

Mashkevich, Stefan, Myrheim, Jan, Ouvry, Stéphane

A two-dimensional quantum mechanical system consisting of a particle coupled to two magnetic impurities of different strengths, in a harmonic potential, is considered. Topological boundary conditions...

Quantum Mechanics of a Particle with Two Magnetic Impurities (2004)

Mashkevich, Stefan, Myrheim, Jan, Ouvry, Stéphane

A two-dimensional quantum mechanical system consisting of a particle coupled to two magnetic impurities of different strengths, in a harmonic potential, is considered. Topological boundary conditions...

Virial Coefficients of Multispecies Anyons (2004)

Mashkevich, Stefan, Myrheim, Jan, Olaussen, Kaare

A path integral formalism for multispecies anyons is introduced, whereby partition functions are expressed in terms of generating functions of winding number probability distributions. In a certain...

Quantum Mechanics of a Particle with Two Magnetic Impurities (2004)

Mashkevich, Stefan, Myrheim, Jan, Ouvry, Stéphane

A two-dimensional quantum mechanical system consisting of a particle coupled to two magnetic impurities of different strengths, in a harmonic potential, is considered. Topological boundary conditions...

Quantum Mechanics of a Particle with Two Magnetic Impurities (2004)

Mashkevich, Stefan, Myrheim, Jan, Ouvry, Stéphane

A two-dimensional quantum mechanical system consisting of a particle coupled to two magnetic impurities of different strengths, in a harmonic potential, is considered. Topological boundary conditions...

Numerical path integration with Coulomb potential (2003)

Myrheim, Jan

A simple and efficient method for quantum Monte Carlo simulation is presented, based on discretization of the action in the path integral, and a Gaussian averaging of the potential, which works well...

Quantum mechanics on a real Hilbert space (1999)

Myrheim, Jan

The complex Hilbert space of standard quantum mechanics may be treated as a real Hilbert space. The pure states of the complex theory become mixed states in the real formulation. It is then possible...

Numerical study of charge and statistics of Laughlin quasi-particles (1998)

Kjonsberg, Heidi, Myrheim, Jan

We present numerical calculations of the charge and statistics, as extracted from Berry phases, of the Laughlin quasi-particles, near filling fraction 1/3, and for system sizes of up to 200...

The fourth virial coefficient of anyons (1997)

Kristoffersen, Anders, Mashkevich, Stefan, Myrheim, Jan, Olaussen, Kaare

We have computed by a Monte Carlo method the fourth virial coefficient of free anyons, as a function of the statistics angle theta. It can be fitted by a four term Fourier series, in which two...

Algebra of Observables for Identical Particles in One Dimension (1997)

Isakov, Serguei B., Leinaas, Jon Magne, Myrheim, Jan, Polychronakos, Alexios P., Varnhagen, Raimund

The algebra of observables for identical particles on a line is formulated starting from postulated basic commutation relations. A realization of this algebra in the Calogero model was previously...

The third virial coefficient of anyons revisited (1996)

Mashkevich, Stefan, Myrheim, Jan, Olaussen, Kåre

We use the method of solving the three-anyon problem developed in our earlier publication to evaluate numerically the third virial coefficient of free anyons. In order to improve precision, we...

Thermodynamics for Fractional Exclusion Statistics (1996)

Isakov, Serguei B., Arovas, Daniel P., Myrheim, Jan, Polychronakos, Alexios P.

We discuss the thermodynamics of a gas of free particles obeying Haldane's exclusion statistics, deriving low temperature and low density expansions. For gases with a constant density of states, we...

Statistical geometry (1996)

Myrheim, Jan

Anyon trajectories and the systematics of the three-anyon spectrum (1995)

Mashkevich, Stefan, Myrheim, Jan, Olaussen, Kåre, Rietman, Ronald

We develop the concept of trajectories in anyon spectra, i.e., the continuous dependence of energy levels on the kinetic angular momentum. It provides a more economical and unified description, since...

Solution of the Three--Anyon Problem (1994)

Mashkevich, Stefan, Myrheim, Jan, Olaussen, Kåre, Rietman, Ronald

We solve, by separation of variables, the problem of three anyons with a harmonic oscillator potential. The anyonic symmetry conditions from cyclic permutations are separable in our coordinates. The...

Studies of particle statistics in one and two dimensions, based on the quantization of Heisenberg, Schrödinger and Feynman / (1993)

Myrheim, Jan.

Trondheim, University, Diss., 1993.

The Third Virial Coefficient of Free Anyons (1992)

Myrheim, Jan, Olaussen, Kåre

We use a path integral representation for the partition function of non-interacting anyons confined in a harmonic oscillator potential in order to prove that the third virial coefficient of free...

Elastic scattering of charged mesons, antiprotons and protons on protons at incident momenta of 20, 30 and 50 GeV/c in the momentum transfer range 0.5 $ (1990)

Asad, Z, Baglin, C, Böck, R K, Bugge, L, Buran, T, Buzzo, A, ...

Proton-proton elastic scattering at 50 GeV/c incident momentum in the momentum transfer range 0.8 $ (1990)

Asad, Z, Baglin, C, Böck, R K, Brom, J M, Bugge, L, Buran, T, ...

$\overline{p}$p elastic scattering at 30 GeV/c incident momentum in the momentum transfer range 0.5 $ (1990)

Asad, Z, Baglin, C, Böck, R K, Brom, J M, Bugge, L, Buran, T, ...

Large-angle elastic scattering of charged pions on protons at 20 and 30 GeV/c incident momenta (1990)

Almas, R, Baglin, C, Böck, R K, Borggaard, E T C, Brobakken, K, Bugge, L, ...

A fast Runge-Kutta method for fitting tracks in a magnetic field (1990)

Myrheim, Jan, Bugge, L

An experimental study of large-angle elastic scattering of charged mesons and antiprotons on protons at 20 and 30 GeV/c incident momenta (1990)

Baglin, C, Böck, R K, Brobakken, K, Bugge, L, Buran, T, Buzzo, A, ...