Lavaei-Yanesi, L., Khorrami, M.
The large-N behavior of the quartic-cubic generalized two dimensional Yang Mills U(N) on the sphere is investigated, for small cubic couplings. It is shown that single transition at the critical area...
Loop diagrams in space with SU(2) fuzziness (2007)
Komaie-Moghaddam, H., Khorrami, M., Fatollahi, A. H.
The structure of loop corrections is examined in a scalar field theory on a three dimensional space whose spatial coordinates are noncommutative and satisfy SU(2) Lie algebra. In particular, the 2-...
Field theory amplitudes in a space with SU(2) fuzziness (2007)
Komaie-Moghaddam, H., Fatollahi, A. H., Khorrami, M.
The structure of transition amplitudes in field theory in a three-dimensional space whose spatial coordinates are noncommutative and satisfy the SU(2) Lie algebra commutation relations is examined....
Non-Douglas-Kazakov phase transition of two-dimensional generalized Yang-Mills theories (2007)
Khorrami, M., Alimohammadi, M.
In two-dimensional Yang-Mills and generalized Yang-Mills theories for large gauge groups, there is a dominant representation determining the thermodynamic limit of the system. This representation is...
Field theories on spaces with linear fuzziness (2006)
Fatollahi, A. H., Khorrami, M.
A noncommutative space is considered the position operators of which satisfy the commutativity relations of a Lie algebra. The basic tools for calculation on this space, including the product of the...
Alimohammadi, M., Khorrami, M.
The large-N behavior of Yang-Mills and generalized Yang-Mills theories in the double-scaling limit is investigated. By the double-scaling limit, it is meant that the area of the manifold on which the...
Large-N behavior of the Wilson loops of generalized two-dimensional Yang-Mills theories (2005)
Khorrami, M., Alimohammadi, M.
The large-N limit of the expectation values of the Wilson loops corresponding to two-dimensional U(N) Yang-Mills and generalized Yang-Mills theories on a sphere are studied. The behavior of the...
Static- and dynamical-phase transition in multidimensional voting models on continua (2004)
Roshani, F., Aghamohammadi, A., Khorrami, M.
A voting model (or a generalization of the Glauber model at zero temperature) on a multidimensional lattice is defined as a system composed of a lattice each site of which is either empty or occupied...
Large-N limit of the two-dimensoinal Yang-Mills theory on surfaces with boundaries (2004)
Alimohammadi, M., Khorrami, M.
The large-N limit of the two-dimensional U$(N)$ Yang-Mills theory on an arbitrary orientable compact surface with boundaries is studied. It is shown that if the holonomies of the gauge field on...
Spin 0 and spin 1/2 quantum relativistic particles in a constant gravitational field (2002)
Khorrami, M., Alimohammadi, M., Shariati, A.
The Klein-Gordon and Dirac equations in a semi-infinite lab ($x > 0$), in the background metric $\ds^2 = u^2(x) (-\dt^2 + \dx^2) + \dy^2 + \dz^2$, are investigated. The resulting equations are...
Discrete scale invariance, and its logarithmic extension (2002)
Abed-Pour, N., Aghamohammadi, A., Khorrami, M., Tabar, M. Reza Rahimi
It is known that discrete scale invariance leads to log-periodic corrections to scaling. We investigate the correlations of a system with discrete scale symmetry, discuss in detail possible extension...
M. Khorrami, B. Singer, D. Lockard, Mehdi R. Khorrami, Bart A. Singer, David P. Lockard
Unsteady computational simulations of a multi-element, high-lift configuration are performed. Emphasis is placed on accurate spatio-temporal resolution of the free shear layer in the slat-cove...
Khorrami, M., Aghamohammadi, A., Alimohammadi, M.
Single-species reaction-diffusion systems on a one-dimensional lattice are considered, in them more than two neighboring sites interact. Constraints on the interaction rates are obtained, that...
Exactly solvable models through the empty interval method (2001)
Alimohammadi, M., Khorrami, M., Aghamohammadi, A.
The most general one dimensional reaction-diffusion model with nearest-neighbor interactions, which is exactly-solvable through the empty interval method, has been introduced. Assuming...
Phase transition in an asymmetric generalization of the zero-temperature q-state Potts model (2001)
Majd, N., Aghamohammadi, A., Khorrami, M.
An asymmetric generalization of the zero-temperature q-state Potts model on a one dimensional lattice, with and without boundaries, has been studied. The dynamics of the particle number, and...
On the phase structure of two--dimensional generalized Yang--Mills theories (2000)
Alimohammadi, M., Khorrami, M.
The phase structure of the generalized Yang--Mills theories is studied, and it is shown that {\it almost} always, it is of the third order. As a specific example, it is shown that all of the models...
Multispecies reaction-diffusion systems (2000)
Aghamohammadi, A., Fatollahi, A. H., Khorrami, M., Shariati, A.
Multispecies reaction-diffusion systems, for which the time evolution equation of correlation functions become a closed set, are considered. A formal solution for the average densities is found. Some...
Equivalence principle and radiation by a uniformly accelerated charged particle (2000)
We address the old question of whether or not a uniformly accelerated charged particle radiates, and consequently, if weak equivalence principle is violated by electrodynamics. We show that radiation...
Large-N limit of the generalized 2D Yang-Mills theory on cylinder (1999)
Khorrami, M., Alimohammadi, M.
Using the collective field theory approach of large-N generalized two-dimensional Yang-Mills theory on cylinder, it is shown that the classical equation of motion of collective field is a generalized...
Exact determination of the phase structure of the p-species asymmetric exclusion process (1999)
We consider a multi-species generalization of the Asymmetric Simple Exclusion Process on an open chain, in which particles hop with their characteristic hopping rates and fast particles can overtake...
Effective time variation of G in a model universe with variable space dimension (1999)
Mansouri, R., Nasseri, F., Khorrami, M.
Time variation of Newtonian gravitational constant, $G$, is studied in the model universe with variable space dimension proposed recently. Using the Lagrangian formulation of these models, we find...
A Triangular Deformation of the two Dimensional Poincar'e Algebra (1998)
M. Khorrami, A. Shariati, M. Abolhasani, A. Aghamohammadi
Contracting the h-deformation of SL(2; R), we construct a new deformation of two dimensional Poincar'e algebra, the algebra of functions on its group and its differential structure. It is also shown...
A two--parametric family of asymmetric exclusion processes and its exact solution (1998)
Alimohammadi, M., Karimipour, V., Khorrami, M.
A two--parameter family of asymmetric exclusion processes for particles on a one-dimensional lattice is defined. The two parameters of the model control the driving force and an effect which we call...
A general formlulation for discrete-time quantum mechanics, based on Feynman's method in ordinary quantum mechanics, is presented. It is shown that the ambiguities present in ordinary quantum...
Exact solution of a one-parameter family of asymmetric exclusion processes (1998)
Alimohammadi, M., Karimipour, V., Khorrami, M.
We define a family of asymmetric processes for particles on a one-dimensional lattice, depending on a continuous parameter $\lambda \in [0,1] $, interpolating between the completely asymmetric...
Logarithmic conformal field theories with continuous weights (1997)
Khorrami, M., Aghamohammadi, A., Tabar, M. R. Rahimi
We study the logarithmic conformal field theories in which conformal weights are continuous subset of real numbers. A general relation between the correlators consisting of logarithmic fields and...
Uniqueness of the minimum of the free energy of the 2D Yang-Mills theory at large N (1997)
Aghamohammadi, A., Alimohammadi, M., Khorrami, M.
There has been some controversies at the large $N$ behaviour of the 2D Yang-Mills and chiral 2D Yang-Mills theories. To be more specific, is there a one parameter family of minima of the free energy...
Large-N limit of the generalized 2-dimensional Yang-Mills theories (1997)
Alimohammadi, M., Khorrami, M., Aghamohammdi, A.
Using the standard saddle-point method, we find an explicit relation for the large-N limit of the free energy of an arbitrary generalized 2D Yang-Mills theory in the weak ($AA_c$) region, we...
Exactly and Quasi-Exactly Solvable Models on the Basis of $osp(2|1)$ (1997)
The exactly and quasi-exactly solvable problems for spin one-half in one dimension on the basis of a hidden dynamical symmetry algebra of Hamiltonian are discussed. We take the supergroup,...
Khorrami, M., Alimohammadi, M.
Using the path integral method, we calculate the partition function and the generating functional (of the field strengths) of the generalized 2D Yang-Mills theories in the Schwinger--Fock gauge. Our...
Derivation of quantum theories:symmetries and the exact solution of the derived system (1996)
Khorrami, M., Aghamohammadi, A., Alimohammadi, M.
Based on the technique of derivation of a theory, presented in our recent paper, we investigate the properties of the derived quantum system. We show that the derived quantum system possesses the...
Phase Transition In One-Dimensional Lattice Gauge Theories (1996)
Considering one-dimensional nonminimally-coupled lattice gauge theories, a class of nonlocal one-dimensional systems is presented, which exhibits phase transition. It is shown that the transition has...
Symmetries in Discrete-Time Mechanics (1996)
Based on a general formulation for discrete-time quantum mechanics, introduced in [1], symmetries in discrete-time quantum mechanics are investigated. It is shown that any classical continuous...
The Logarithmic Conformal Field Theories (1996)
We study the correlation functions of logarithmic conformal field theories. First, assuming conformal invariance, we explicitly calculate two-- and three-- point functions. This calculation is done...
A pseudo-conformal representation of the Virasoro algebra (1996)
Aghamohammadi, A., Alimohammadi, A., Khorrami, M.
Generalizing the concept of primary fields, we find a new representation of the Virasoro algebra, which we call it a pseudo-conformal representation. In special cases, this representation reduces to...
The Logarithmic Conformal Field Theories (1996)
Tabar, M. R. Rahimi, Aghamohammadi, A., Khorrami, M.
We study the correlation functions of logarithmic conformal field theories. First, assuming conformal invariance, we explicitly calculate two-- and three-- point functions. This calculation is done...
Khorrami, M., Aghamohammadi, A.
We present the technique of derivation of a theory to obtain an $(n+1)f$-degrees-of-freedom theory from an $f$-degrees-of-freedom theory and show that one can calculate all of the quantities of the...
A. Shariati, A. Aghamohammadi, M. Khorrami
We introduce a universal R matrix for the Jordanian deformation of U (sl(2)). Using U h (so(4)) = U h (sl(2)) Phi U Gammah (sl(2)), we obtain the universal R matrix for U h (so(4)). Applying the...
H-Deformation As A Contraction Of (1996)
A. Aghamohammadi, M. Khorrami, A. Shariati
We show that h-deformation can be obtained, by a singular limit of a similarity transformation, from q-deformation; to be specefic, we obtain GL h (2), its differential structure, its inhomogenous...
A Triangular Deformation Of The Two Dimensional Poincaré Algebra (1996)
M. Khorrami, A. Shariati, M. R. Abolhassani, A. Aghamohammadi
Contracting the h-deformation of SL(2; R), we construct a new deformation of two dimensional Poincar'e algebra, the algebra of functions on its group and its differential structure. It is seen that...
A Model Universe With Variable Dimension: Expansion As Decrumpling (1996)
M. Khorrami, R. Mansouri, M. Mohazzab, M. R. Ejtehadi
We propose a model universe, in which the dimension of the space is a continuous variable, which can take any real positive number. The dynamics leads to a model in which the universe has no...
A. Shariati, A. Aghamohammadi, M. Khorrami
We introduce a universal R matrix for the Jordanian deformation of U (sl(2)). Using Uh (so(4)) = Uh (sl(2))PhiU Gammah (sl(2)), we obtain the universal R matrix for Uh (so(4)). Applying the graded...
Toda theories as contraction of affine Toda theories (1996)
Aghamohammadi, A., Khorrami, M., Shariati, A.
Using a contraction procedure, we obtain Toda theories and their structures, from affine Toda theories and their corresponding structures. By structures, we mean the equation of motion, the classical...
Green functions of 2-dimensional Yang-Mills theories on nonorientable surfaces (1996)
Alimohammadi, M., Khorrami, M.
By using the path integral method , we calculate the Green functions of field strength of Yang-Mills theories on arbitrary nonorientable surfaces in Schwinger-Fock gauge. We show that the non-gauge...
A distributional method to solve the Einstein's field equations for thin shells is formulated. The familiar field equations and jump conditions of Darmois-Israel formalism are derived. A carefull...
A Decrumpling Model of the Universe (1996)
Khorrami, M., Mansouri, M., Mohazzab, M.
Assuming a cellular structure for the space-time, we propose a model in which the expansion of the universe is understood as a decrumpling process, much like the one we know from polymeric surfaces....
$n$-point functions of $2d$ Yang-Mills theories on Riemann surfaces (1996)
Alimohammadi, M., Khorrami, M.
Using the simple path integral method we calculate the $n$-point functions of field strength of Yang-Mills theories on arbitrary two-dimensional Riemann surfaces. In $U(1)$ case we show that the...
Shariati, A., Aghamohammadi, A., Khorrami, M.
We introduce a universal R matrix for the Jordanian deformation of $\U{ \sl(2)}$. Using $\Uh{\so(4)}=\Uh{\sl(2)} \oplus {\rm U}_{-h}(\sl(2))$, we obtain the universal R matrix for $\Uh{\so(4)}$....
On the Classification of quantum qroup stuctures on the group GL(2) (1995)
Aghamohammadi, A., Khorrami, M., Shariati, A.
All quantum group structures on the group GL(2) are classified. It is shown that there are only two such structures, the well known quantum groups GL$_{qp}$(2) and GL$_{hh'}$(2).
A model universe with variable dimension: Expansion as decrumpling (1995)
Khorrami, M., Mansouri, R., Mohazzab, M., Ejtehadi, M. R.
We propose a model universe, in which the dimension of the space is a continuous variable, which can take any real positive number. The dynamics leads to a model in which the universe has no...
A general formlulation for discrete-time quantum mechanics, based on Feynman's method in ordinary quantum mechanics, is presented. It is shown that the ambiguities present in ordinary quantum...
Phase transition in one-dimensional lattice gauge theories (1994)
Considering one-dimensional nonminimally-coupled lattice gauge theories, a class of nonlocal one-dimensional systems is presented, which exhibits a phase transition. It is shown that the transition...
A Triangular Deformation of the two Dimensional Poincare Algebra (1994)
Khorrami, M., Shariati, A., Abolhassani, M., Aghamohammadi, A.
Contracting the $h$-deformation of $\SL(2,\Real)$, we construct a new deformation of two dimensional Poincar\'e algebra, the algebra of functions on its group and its differential structure. It is...
$h$-Deformation as a Contraction of $q$-Deformation (1994)
Aghamohammadi, A., Khorrami, M., Shariati, A.
We show that $h$-deformation can be obtained, by a singular limit of a similarity transformation, from $q$-deformation; to be specefic, we obtain $\GL_h(2)$, its differential structure, its...
Exact Solution for the Most General Minimally Coupled One Dimensional Lattice Gauge Theory (1993)
We consider one dimensional lattice gauge theories constructed by the minimal coupling prescription. It is shown that these theories are exactly solvable in the thermodynamic limit. After considering...