High Precision Renormalization Group Study of the Roughening Transition (2003)
Hasenbusch, M, Marcu, M, Pinn, K
We confirm the Kosterlitz-Thouless scenario of the roughening transition for three different Solid-On-Solid models: the Discrete Gaussian model, the Absolute-Value-Solid-On-Solid model and the dual...
Width of Rough Interfaces on Asymmetric Lattices (1999)
I present a calculation of the interfacial width within the capillary wave (Gaussian) approximation. The calculation is done on rectangular lattices of size L_1 times L_2, with periodic boundary...
Minimal Variance Hedging of Options with Student-t Underlying (1999)
I explicitly work out closed form solutions for the optimal hedging strategies (in the sense of Bouchaud and Sornette) in the case of European call options, where the underlying is modeled by...
A Chaotic Cousin Of Conway's Recursive Sequence (1998)
I study the recurrence D(n)= D(D(n-1))+D(n-1-D(n-2)), D(1)=D(2)=1. Its definition has some similarity to that of Conway's sequence defined through a(n)= a(a(n-1))+a(n-a(n-1)), a(1)=a(2)=1. However,...
Zeroes in the Complex Beta Plane Of 2D Ising Block Spin Boltzmannians (1998)
Effective Boltzmannians in the sense of the block spin renormalization group are computed for the 2D Ising model. The blocking is done with majority and Kadanoff rules for blocks of size 2 by 2....
Monte Carlo Algorithms For the Fully Frustrated XY Model (1998)
We investigate local update algorithms for the fully frustrated XY model on a square lattice. In addition to the standard updating procedures like the Metropolis or heat bath algorithm we include...
Hasenbusch, M., Pinn, K., Vinti, S.
We propose a method to obtain an improved Hamiltonian (action) for the Ising universality class in three dimensions. The improved Hamiltonian has suppressed leading corrections to scaling. It is...
Pinn, K., Rehwald, M., Wieczerkowski, C.
We compute renormalization group fixed points and their spectrum in an ultralocal approximation. We study a case of two competing non-trivial fixed points for a three-dimensional real $N$-component...
3D Ising Model with Improved Scaling Behaviour (1998)
Hasenbusch, M., Pinn, K., Vinti, S.
We present results from the simulation of a two-coupling spin-1 model with states 0,+1,-1 and nearest neighbour interaction. By a suitable choice of couplings we are able to drastically reduce the...
Number of Magic Squares From Parallel Tempering Monte Carlo (1998)
There are 880 magic squares of size 4 by 4, and 275,305,224 of size 5 by 5. It seems very difficult if not impossible to count exactly the number of higher order magic squares. We propose a method to...
Order and Chaos in Hofstadter's Q(n) Sequence (1998)
A number of observations are made on Hofstadter's integer sequence defined by Q(n)= Q(n-Q(n-1))+Q(n-Q(n-2)), for n > 2, and Q(1)=Q(2)=1. On short scales the sequence looks chaotic. It turns out,...
Block Spin Effective Action for 4d SU(2) Finite Temperature Lattice Gauge Theory (1997)
The Svetitsky-Yaffe conjecture for finite temperature 4d SU(2) lattice gauge theory is confirmed by observing matching of block spin effective actions of the gauge model with those of the 3d Ising...
New Estimates On Various Critical/Universal Quantities of the 3D Ising Model (1997)
We present estimates for the 3D Ising model on the cubic lattice, both regarding interface and bulk properties. We have results for the interface tension, in particular the amplitude sigma0 in the...
Block Spin Effective Action for Polyakov Loops in 4D SU(2) LGT (1997)
Using a variant of the IMCRG method of Gupta and Cordery, we explicitly compute majority rule block spin effective actions for the signs of the Polyakov loops in 4D SU(2) finite temperature lattice...
A_+/A_-, alpha, nu, and f_s xi^3 from 3D Ising Energy and Specific Heat (1997)
We analyse Monte Carlo data for the energy and specific heat at and close to the critical point of the 3D cubic Ising model. From the finite size scaling of the energy E and the specific heat C at...
The Interface Tension of the 3-Dimensional Ising Model in the Scaling Region (1997)
Using the Monte Carlo method, we determine the free energy of the interface of the 3D Ising model in the scaling region. By integrating the interface energies over the inverse temperature $\beta$, we...
We study the roughening transition of the dual of the 2D XY model, of the Discrete Gaussian model, of the Absolute Value Solid-On-Solid model and of the interface in an Ising model on a 3D simple...
We consider the question of removing the ultraviolet cutoff in a 2D Quantum Field Theory with an interaction term which is non-renormalizable by power counting. This model arises as the first...
Iterating Block Spin Transformations of the O(3) Non-Linear Sigma-Model (1996)
Gottlob, A. P., Hasenbusch, M., Pinn, K.
We study the iteration of block spin transformations in the O(3) symmetric non-linear sigma-model on a two-dimensional square lattice with help of the Monte Carlo method. In contrast to the classical...
Rough Interfaces Beyond the Gaussian Approximation (1994)
Caselle, M., Gliozzi, F., Fiore, R., Hasenbusch, M., Pinn, K., Vinti, S.
We compare predictions of the Capillary Wave Model with Monte Carlo results for the energy gap and the interface energy of the 3D Ising model in the scaling region. Our study reveals that the finite...
Canonical Demon Monte Carlo Renormalization Group (1994)
Hasenbusch, M., Pinn, K., Wieczerkowski, C.
We describe a method to compute renormalized coupling constants in a Monte Carlo renormalization group calculation. It can be used, e.g., for lattice spin or gauge models. The basic idea is to...
The sine Gordon model: perturbation theory and cluster Monte Carlo (1994)
Hasenbusch, M, Marcu, M, Pinn, K
We study the expansion of the surface thickness in the 2-dimensional lattice Sine Gordon model in powers of the fugacity z. Using the expansion to order z**2, we derive lines of constant physics in...
The Sine Gordon Model: Perturbation Theory and Cluster Monte Carlo (1994)
Hasenbusch, M., Marcu, M., Pinn, K.
We study the expansion of the surface thickness in the 2-dimensional lattice Sine Gordon model in powers of the fugacity z. Using the expansion to order z**2, we derive lines of constant physics in...
Rough interfaces beyond the Gaussian approximation (1994)
Caselle, M, Fiore, R, Gliozzi, F, Hasenbusch, M, Pinn, K, Vinti, S
We compare predictions of the Capillary Wave Model beyond its Gaussian approximation with Monte Carlo results for the energy gap and the surface energy of the 3D Ising model in the scaling region....
Rough Interfaces Beyond the Gaussian Approximation (1994)
Caselle, M., Fiore, R., Gliozzi, F., Hasenbusch, M., Pinn, K., Vinti, S.
We compare predictions of the Capillary Wave Model beyond its Gaussian approximation with Monte Carlo results for the energy gap and the surface energy of the 3D Ising model in the scaling region....
Canonical demon Monte Carlo renormalization group (1994)
Hasenbusch, M, Pinn, K, Wieczerkowski, C
We describe a new method to compute renormalized coupling constants in a Monte Carlo renormalization group calculation. The method can be used for a general class of models, e.g., lattice spin or...
Canonical Demon Monte Carlo Renormalization Group (1994)
Hasenbusch, M., Pinn, K., Wieczerkowski, C.
We describe a new method to compute renormalized coupling constants in a Monte Carlo renormalization group calculation. The method can be used for a general class of models, e.g., lattice spin or...
Multigrid Monte Carlo Algorithms for SU(2) Lattice Gauge Theory: Two versus Four Dimensions (1994)
We study a multigrid method for nonabelian lattice gauge theory, the time slice blocking, in two and four dimensions. For SU(2) gauge fields in two dimensions, critical slowing down is almost...
High Precision Renormalization Group Study of the Roughening Transition (1994)
Hasenbusch, M., Marcu, M., Pinn, K.
We confirm the Kosterlitz-Thouless scenario of the roughening transition for three different Solid-On-Solid models: the Discrete Gaussian model, the Absolute-Value-Solid-On-Solid model and the dual...
Pinn, K., Pordt, A., Wieczerkowski, C.
Nontrivial fixed points of the hierarchical renormalization group are computed by numerically solving a system of quadratic equations for the coupling constants. This approach avoids a fine tuning of...
Computing masses and surface tension from effective transfer matrices (1993)
Hasenbusch, M, Pinn, K, Rummukainen, K
We propose an effective transfer-matrix method that allows a measurement of tunnelling correlation lengths that are orders of magnitude larger than the lattice extension. Combining this method with a...
Computing Masses and Surface Tension from Effective Transfer Matrices (1993)
Hasenbusch, M., Rummukainen, K., Pinn, K.
We propose an effective transfer-matrix method that allows a measurement of tunnelling correlation lengths that are orders of magnitude larger than the lattice extension. Combining this method with a...
Computing masses and surface tension from effective transfer matrices (1993)
Hasenbusch, M, Rummukainen, K, Pinn, K
We propose an effective transfer-matrix method that allows a measurement of tunnelling correlation lengths that are orders of magnitude larger than the lattice extension. Combining this method with a...
Monte Carlo simulation of 2-D quantum gravity as open dynamically triangulate random surfaces (1993)
Adi, E, Hasenbusch, M, Marcu, M, Pazy, E, Pinn, K, Solomon, S
We describe a Monte Carlo procedure for the simulation of dynamically triangulate random surfaces with a boundary (topology of a disk). The algorithm keeps the total number of triangles fixed, while...
We compare Monte Carlo results for the interface tension and interface energy of the 3-dimensional Ising model with Pad\'e and inhomogeneous differential approximants of the low temperature series...
Monte Carlo Simulation of 2-D Quantum Gravity as Open Dynamically Triangulate Random Surfaces (1993)
Adi, E., Hasenbusch, M., Marcu, M., Pazy, E., Pinn, K., Solomon, S.
We describe a Monte Carlo procedure for the simulation of dynamically triangulate random surfaces with a boundary (topology of a disk). The algorithm keeps the total number of triangles fixed, while...
We compare Monte Carlo results for the interface tension and interface energy of the 3-dimensional Ising model with Pad\'e and inhomogeneous differential approximants of the low temperature series...
The solid-on-solid surface width around the roughening transition (1993)
Evertz, H G, Hasenbusch, M, Marcu, M, Pinn, K
We investigate the surface width $W$ of solid-on-solid surfaces in the vicinity of the roughening temperature $T_r$. Above $T_r$, $W^2$ is expected to diverge with the system size $L$ like $\ln L$....
The Solid-on-Solid Surface Width Around the Roughening Transition (1993)
Evertz, H. G., Hasenbusch, M., Marcu, M., Pinn, K.
We investigate the surface width $W$ of solid-on-solid surfaces in the vicinity of the roughening temperature $T_r$. Above $T_r$, $W^2$ is expected to diverge with the system size $L$ like $\ln L$....
Computing Masses from Effective Transfer Matrices (1993)
Hasenbusch, M, Pinn, K, Rummukainen, K
We study the use of effective transfer matrices for the numerical computation of masses (or correlation lengths) in lattice spin models. The effective transfer matrix has a strongly reduced number of...
Computing Masses from Effective Transfer Matrices (1993)
Hasenbusch, M., Pinn, K., Rummukainen, K.
We study the use of effective transfer matrices for the numerical computation of masses (or correlation lengths) in lattice spin models. The effective transfer matrix has a strongly reduced number of...
Cluster Algorithm for a Solid-On-Solid Model with Constraints (1992)
Hasenbusch, M., Lana, G., Marcu, M., Pinn, K.
We adapt the VMR (valleys-to-mountains reflections) algorithm, originally devised by us for simulations of SOS models, to the BCSOS model. It is the first time that a cluster algorithm is used for a...
High Precision Verification of the Kosterlitz Thouless Scenario (1992)
Hasenbusch, M., Marcu, M., Pinn, K.
We verify the Kosterlitz Thouless scenario for three different SOS (solid-on-solid) models, including the dual transforms of XY-models with Villain and with cosine action. The method is based on a...
Kinematics of Multigrid Monte Carlo (1992)
We study the kinematics of multigrid Monte Carlo algorithms by means of acceptance rates for nonlocal Metropolis update proposals. An approximation formula for acceptance rates is derived. We present...
Acceptance Rates in Multigrid Monte Carlo (1992)
An approximation formula is derived for acceptance rates of nonlocal Metropolis updates in simulations of lattice field theories. The predictions of the formula agree quite well with Monte Carlo...