共查询到20条相似文献,搜索用时 23 毫秒
1.
We construct the Euclidean Green functions for the soliton (magnetic monopole) field in the U(1)4 Lattice Gauge Theory with Wilson action. We show that in the strong coupling regime there is monopole condensation while
in the QED phase the physical Hilbert space splits into orthogonal soliton sectors labeled by integer magnetic charge.
Received: 2 July 1997 / Accepted: 20 July 1998 相似文献
2.
Marcio Jose Martins 《Physics letters. [Part B]》1990,240(3-4):404-406
We use the thermodynamic Bethe ansatz approach in order to study the ultraviolet limit behaviour of the ground state in two sets of integrable field theories: the Z(N) invariant model and a special series of massive non-unitary minimal theories. We obtain the value of respective effective central charges and confirm that these integrable models are indeed the corresponding perturbed conformal field theories. 相似文献
3.
P. A. Marchetti 《Communications in Mathematical Physics》1988,117(3):501-528
We discuss the particle structure in the soliton sectors of massive lattice field theories by means of convergent cluster expansions. In several models we prove that the soliton field operator with lowest charge couples the vacuum to a stable one-particle state, in a suitable region of the coupling parameter space. Both local and stringlike solitons are analyzed. We also show that the mass of the local soliton equals the surface tension. 相似文献
4.
Conditions are analysed under which the statistics of soliton sectors of massive two-dimensional field theories can be properly defined. A soliton field algebra is defined as a crossed product with the group of soliton sectors. In this algebra, the nonlocal commutation relations are determined and weak locality, spin statistics and CPT theorems are proven. These theorems depart from their usual appearance due to the broken symmetry connecting the inequivalent vacua. An interpretation of these results in terms of modular theory is given. For the neutral subalgebra of the soliton algebra, the theorems hold in a familiar form, and twisted duality is derived. 相似文献
5.
We formulate a general gauge invariant Lagrangian construction describing the dynamics of massive higher spin fermionic fields in arbitrary dimensions. Treating the conditions determining the irreducible representations of Poincaré group with given spin as the operator constraints in auxiliary Fock space, we built the BRST charge for the model under consideration and find the gauge invariant equations of motion in terms of vectors and operators in the Fock space. It is shown that like in massless case [I.L. Buchbinder, V.A. Krykhtin, A. Pashnev, Nucl. Phys. B 711 (2005) 367, hep-th/0410215], the massive fermionic higher spin field models are the reducible gauge theories and the order of reducibility grows with the value of spin. In compare with all previous approaches, no off-shell constraints on the fields and the gauge parameters are imposed from the very beginning, all correct constraints emerge automatically as the consequences of the equations of motion. As an example, we derive a gauge invariant Lagrangian for massive spin 3/2 field. 相似文献
6.
We introduce an exactly solvable SU(2)-invariant spin-1/2 model with exotic spin excitations. With time reversal symmetry (TRS), the ground state is a spin liquid with gapless or gapped spin-1 but fermionic excitations. When TRS is broken, the resulting spin liquid exhibits deconfined vortex excitations which carry spin-1/2 and obey non-Abelian statistics. We show that this SU(2) invariant non-Abelian spin liquid exhibits the spin quantum Hall effect with quantized spin Hall conductivity σ(xy)(s)=?/2π, and that the spin response is effectively described by the SO(3) level-1 Chern-Simons theory at low energy. We further propose that a SU(2) level-2 Chern-Simons theory is the effective field theory describing the topological structure of the non-Abelian SU(2) invariant spin liquid. 相似文献
7.
《Physics letters. [Part B]》1988,214(3):475-479
We reexamine the questions of spin and statistics of nonrelativiic charged particles coupled to a topologically massive abelian gauge field. We show that these particles obey fractional statistics and carry an extra (gauge invariant) spin so that the generalized spin statistics relation is fulfilled. In particular, if the topological mass is obtained from integrating out heavy fermion fields, two flavors of fermions are needed to turn bosons into fermions. We also show, by explicitly considering the Dirac vacuum in the presence of a heavy point particle, that screening charge is exponentially localized and that the fermions do not contribute to the (gauge invariant) spin of the particle. 相似文献
8.
Dario Bambusi 《Communications in Mathematical Physics》2013,320(2):499-542
We consider a ground state (soliton) of a Hamiltonian PDE. We prove that if the soliton is orbitally stable, then it is also asymptotically stable. The main assumptions are transversal nondegeneracy of the manifold of the ground states, linear dispersion (in the form of Strichartz estimates) and nonlinear Fermi Golden Rule. We allow the linearization of the equation at the soliton to have an arbitrary number of eigenvalues. The theory is tailor made for the application to the translational invariant NLS in space dimension 3. The proof is based on the extension of some tools of the theory of Hamiltonian systems (reduction theory, Darboux theorem, normal form) to the case of systems invariant under a symmetry group with unbounded generators. 相似文献
9.
10.
We propose a new method to obtain the correlation length of gapped XXZ spin 1/2 antiferromagnetic chains. Following the relativistic quantum field theory in (1+ 1) space-time dimensions, we use the exact dispersion of massive spinon to calculate the correlation length for XXZ spin 1/2 chain. We conjecture that the correlation length for other 1D lattice models can be obtained in the same way. Relation between dispersion and the oscillated correlation of gapped incommensurate lattice models is also discussed. 相似文献
11.
We propose a new method to obtain the correlation length of gapped XXZ spin 1/2 antiferromagnetic chains.Following the relativistic quantum field theory in (1 1) space-time dimensions,we use the exact dispersion of massive spinon to correlation length for XXZ spin 1/2 chain.We conjecture that the correlation length for other 1D lattice models can be obtained in the same way.Relation between dispersion and the oscillated correlation of gapped incommensurate lattice models is also discussed. 相似文献
12.
Geometric –models have been defined as purely geometric theories of scalar fields in interaction with gravity. By construction, these theories possess soliton solutions with topologically nontrivial scalar sectors. We perform a detailed analysis of the stability of the effective scalar field theory far from the soliton core. It is shown that the requirement for the asymptotic stability is consistent with the existence of massive, static, spherically symmetric soliton solutions. 相似文献
13.
We explore the ground states and quantum phase transitions of two-dimensional, spin S=1/2, antiferromagnets by generalizing lattice models and duality transforms introduced by Sachdev and Jalabert (1990, Mod. Phys. Lett. B4, 1043). The minimal model for square lattice antiferromagnets is a lattice discretization of the quantum nonlinear sigma model, along with Berry phases which impose quantization of spin. With full SU(2) spin rotation invariance, we find a magnetically ordered ground state with Néel order at weak coupling and a confining paramagnetic ground state with bond charge (e.g., spin Peierls) order at strong coupling. We study the mechanisms by which these two states are connected in intermediate coupling. We extend the minimal model to study different routes to fractionalization and deconfinement in the ground state, and also generalize it to cases with a uniaxial anisotropy (the spin symmetry groups is then U(1)). For the latter systems, fractionalization can appear by the pairing of vortices in the staggered spin order in the easy-plane; however, we argue that this route does not survive the restoration of SU(2) spin symmetry. For SU(2) invariant systems we study a separate route to fractionalization associated with the Higgs phase of a complex boson measuring noncollinear, spiral spin correlations: we present phase diagrams displaying competition between magnetic order, bond charge order, and fractionalization, and discuss the nature of the quantum transitions between the various states. A strong check on our methods is provided by their application to S=1/2 frustrated antiferromagnets in one dimension: here, our results are in complete accord with those obtained by bosonization and by the solution of integrable models. 相似文献
14.
Taku Matsui 《Communications in Mathematical Physics》2001,218(2):393-416
We consider the relationship between the symmetry breaking and the split property of pure states of quantum spin chains.
We obtain a representation theoretic condition implying that the half-sided uniform mixing condition leads to symmetry breaking
of translationally invariant pure states. This is a mathematical generalization of Dichotomy previously found by I. Affleck and E. Lieb and M. Aizenman and B. Nachtergaele for ground states of a special class of Hamiltonians.
Received: 1 February 1999 / Accepted: 5 December 2000 相似文献
15.
T. Matsui 《Communications in Mathematical Physics》1990,135(1):79-89
We study certain quantum spin systems which are equivalent to stochastic Ising models. We show that any translationally invariant quantum ground state is given by integration of Gibbs measure. The existence of mass gap is shown to be the same as exponentially fast convergence of stochastic models to invariant states. 相似文献
16.
N. Iorgov S. Pakuliak V. Shadura Y. Tykhyy G. von Gehlen 《Journal of statistical physics》2010,139(5):743-768
We derive spin operator matrix elements between general eigenstates of the superintegrable ℤ
N
-symmetric chiral Potts quantum chain of finite length. Our starting point is the extended Onsager algebra recently proposed
by Baxter. For each pair of spaces (Onsager sectors) of the irreducible representations of the Onsager algebra, we calculate
the spin matrix elements between the eigenstates of the Hamiltonian of the quantum chain in factorized form, up to an overall
scalar factor. This factor is known for the ground state Onsager sectors. For the matrix elements between the ground states
of these sectors we perform the thermodynamic limit and obtain the formula for the order parameters. For the Ising quantum
chain in a transverse field (N=2 case) the factorized form for the matrix elements coincides with the corresponding expressions obtained recently by the
Separation of Variables method. 相似文献
17.
We establish the connection between the generating functional for the first class theories and the generating functional for the second class theories using the finite field dependent BRST (FFBRST) transformation. We show this connection with the help of explicit calculations in two different models. The generating functional of the Proca model is obtained from the generating functional of the Stueckelberg theory for massive spin 1 vector field using FFBRST transformation. In the other example we relate the generating functionals for gauge invariant and gauge variant theories for a self-dual chiral boson. 相似文献
18.
We find a relation between the spectrum of solitons of massiveN=2 quantum field theories ind=2 and the scaling dimensions of chiral fields at the conformal point. The condition that the scaling dimensions be real imposes restrictions on the soliton numbers and leads to a classification program for symmetricN=2 conformal theories and their massive deformations in terms of a suitable generalization of Dynkin diagrams (which coincides with the A-D-E Dynkin diagrams for minimal models). The Landau-Ginzburg theories are a proper subset of this classification. In the particular case of LG theories we relate the soliton numbers with intersection of vanishing cycles of the corresponding singularity; the relation between soliton numbers and the scaling dimensions in this particular case is a well known application of Picard-Lefschetz theory. 相似文献
19.
We consider the one dimensional, periodic spin chain with N sites, similar to the one studied by Haldane [1], however in the opposite limit of very large anisotropy and small nearest neighbour, anti-ferromagnetic exchange coupling between the spins, which are of large magnitude s. For a chain with an even number of sites we show that actually the ground state is non-degenerate and given by a superposition of the two Neél states, due to quantum spin tunnelling. With an odd number of sites, the Neél state must necessarily contain a soliton. The position of the soliton is arbitrary thus the ground state is N-fold degenerate. This set of states reorganizes into a band. We show that this occurs at order 2s in perturbation theory. The ground state is non-degenerate for integer spin, but degenerate for half-odd integer spin as is required by Kramers' theorem [18]. 相似文献
20.
《Nuclear Physics B》2005,727(3):537-563
We develop the BRST approach to Lagrangian formulation for massive higher integer spin fields on a flat space–time of arbitrary dimension. General procedure of gauge invariant Lagrangian construction describing the dynamics of massive bosonic field with any spin is given. No off-shell constraints on the fields (like tracelessness) and the gauge parameters are imposed. The procedure is based on construction of new representation for the closed algebra generated by the constraints defining an irreducible massive bosonic representation of the Poincaré group. We also construct Lagrangian describing propagation of all massive bosonic fields simultaneously. As an example of the general procedure, we derive the Lagrangians for spin-1, spin-2 and spin-3 fields containing total set of auxiliary fields and gauge symmetries of free massive bosonic higher spin field theory. 相似文献