共查询到20条相似文献,搜索用时 46 毫秒
1.
Kh. Namsrai 《International Journal of Theoretical Physics》1984,23(11):1031-1041
An interrelation between the properties of the space-time structure near moving particles and their dynamics is discussed. It is suggested that the space-time metric near particles becomes a curved one
depending on a random vectorb
E
=(b
4,b) with a distributionw(b
E
2
/l
2); the averaged space-time metric
over this distribution gives the general effect on particle behavior. As a result the particle motion in our scheme is described by a nonlinear equation. It turns out that the nonrelativistic limit of this equation gives a simple connection between the space-time structure at small distances and the dynamical behavior of particles. Different types of particle motion (nearly rectilinear, stochastic, and solitonlike) caused by some concrete forms of the averaged conformally flat space-time metric
are considered. 相似文献
2.
Hirokazu Nishimura 《International Journal of Theoretical Physics》1994,33(6):1173-1188
Any manual
of Boolean locales in the strong sense, namely a subcategory of the opposite category
of the category
of complete Boolean algebras and complete Boolean homomorphisms satisfying not only conditions (3.1)–(3.10) of our previous paper [International Journal of Theoretical Physics,32, 1293 (1993b)], but also conditions (4.1)–(4.4) of that paper, is shown to be representable as the second-class orthomodular manual
of Boolean locales on an orthomodular poset
In this sense the study on manuals of Boolean locales in the strong sense is tantamount to the study on a special class of orthomodular posets, though our viewpoint is radically different from the conventional one in the traditional approach to orthomodular posets. Then the notion of a manual of Hilbert spaces or exactly what is called a manual of Hilbert locales is introduced, over which a variant of the celebrated Gelfand-Naimark-Segal theorem for a manual of Boolean locales in the strong sense is established. 相似文献
3.
The CPT Group of the Dirac Field 总被引:2,自引:2,他引:0
Miguel Socolovsky 《International Journal of Theoretical Physics》2004,43(9):1941-1967
Using the standard representation of the Dirac equation, we show that, up to signs, there exist only two sets of consistent solutions for the matrices of charge conjugation (C), parity (P), and time reversal (T), which give the transformation of fields
,
and
, where
and
. These sets are given by
,
,
and
,
,
. Then
, and two successive applications of the parity transformation to fermion fields necessarily amount to a 2 rotation. Each of these sets generates a non abelian group of 16 elements, respectively,
and
, which are non isomorphic subgroups of the Dirac algebra, which, being a Clifford algebra, gives a geometric nature to the generators, in particular to charge conjugation. It turns out that
and
, where
is the dihedral group of eight elements, the group of symmetries of the square, and 16E is a non trivial extension of
by
, isomorphic to a semidirect product of these groups; S6 and S8 are the symmetric groups of six and eight elements. The matrices are also given in the Weyl representation, suitable for taking the massless limit, and in the Majorana representation, describing self-conjugate fields. Instead, the quantum operators C, P and T, acting on the Hilbert space, generate a unique group
, which we call the CPT group of the Dirac field. This group, however, is compatible only with the second of the above two matrix solutions, namely with
, which is then called the matrix CPT group. It turns out that
, where
is the dicyclic group of 8 elements and S10 is the symmetric group of 10 elements. Since
, the quaternion group, and
, the 0-sphere, then
. 相似文献
4.
Stefano De Leo Zbigniew Oziewicz Waldyr A. Rodrigues Jayme Vaz 《International Journal of Theoretical Physics》1999,38(9):2349-2369
We formulate the variational principle of theDirac equation within the noncommutative even space-timesubalgebra, the Clifford
-algebra
. A fundamental ingredient in ourmultivectorial algebraic formulation is a
-complex geometry,
. We derive the Lagrangian for theDirac-Hestenes equation and show that it must be mapped on
, where denotes an
-algebra of functions. 相似文献
5.
Sergio Doplicher Daniel Kastler Derek W. Robinson 《Communications in Mathematical Physics》1966,3(1):1-28
Starting from aC*-algebra
and a locally compact groupT of automorphisms of
we construct a covariance algebra
with the property that the corresponding *-representations are in one-to-one correspondence with covariant representations of
i.e. *-representations of
in which the automorphisms are continuously unitarily implemented. We further construct for relativistic field theory an algebra
yielding the *-representations of
in which the space time translations have their spectrum contained inV. The problem of denumerable occurence of superselection sectors is formulated as a condition on the spectrum of
. Finally we consider the covariance algebra
built with space translations alone and show its relevance for the discussion of equilibrium states in statistical mechanics, namely we restore in this framework the equivalence of uniqueness of the vacuum, irreducibility and a weak clustering property.On leave of absence from Istituto di Fisica G. Marconi — Roma. 相似文献
6.
Michael Keyl 《International Journal of Theoretical Physics》1998,37(1):375-385
The major subject of algebraic quantum fieldtheory is the study of nets of local C*-algebras, i.e.,maps
(
) assigning to each open,relatively compact region of space-time (M, g) aC*-algebra
(
), whose self-adjoint elements describe localobservables measurable in the region
. A question discussed recently in a number ofpapers is how much information about the geometricstructure of the underlying space-time (M, g) is encoded in the algebraicstructure of the net
(
). Followingthese ideas, it is demonstrated in this paper howspace-time-related concepts like causality and observerscan be described in a purely algebraic way, i.e., using only thelocal algebras
(
).These results are then used to show how the space-time(M, g) can be reconstructed from the set
loc := {
(
)|
M open,
compact} of local algebras. 相似文献
7.
Horng-Tzer Yau 《Communications in Mathematical Physics》1996,181(2):367-408
Let
denote the grand canonical Gibbs measure of a lattice gas in a cube of sizeL with the chemical potential and a fixed boundary condition. Let
be the corresponding canonical measure defined by conditioning
on
. Consider the lattice gas dynamics for which each particle performs random walk with rates depending on near-by particles. The rates are chosen such that, for everyn andL fixed,
is a reversible measure. Suppose that the Dobrushin-Shlosman mixing conditions holds for
forall chemical potentials . We prove that
for any probability densityf with respect to
; here the constant is independent ofn orL andD denotes the Dirichlet form of the dynamics. The dependence onL is optimal.Research partially supported by U.S. National Science Foundations grant 9403462, Sloan Foundation Fellowship and David and Lucile Packard Foundation Fellowship. 相似文献
8.
José M. Figueroa-O'Farrill 《Communications in Mathematical Physics》1996,177(1):129-156
Let
be a finite-dimensional Lie algebra (not necessarily semisimple). It is known that if
is self-dual (that is, if it possesses an invariant metric) then it admits anN=1 (affine) Sugawara construction. Under certain additional hypotheses, thisN=1 structure admits anN=2 extension. If this is the case,
is said to possess anN=2 structure. It is also known that anN=2 structure on a self-dual Lie algebra
is equivalent to a vector space decomposition
, where
are isotropic Lie subalgebras. In other words,N=2 structures on
in one-to-one correspondence with Manin triples
. In this paper we exploit this correspondence to obtain a classification of thec=9N=2 structures on solvable Lie algebras. In the process we also give some simple proofs for a variety of Lie algebras. In the process we also give some simple proofs for a variety of Lie algebraic results concerning self-dual Lie algebras admitting symplectic or Kähler structures. 相似文献
9.
B. Enriquez 《Communications in Mathematical Physics》1995,170(1):197-206
We propose a quantum lattice version of B. Feigin and E. Frenkel's constructions, identifying the KdV differential polynomials with functions on a homogeneous space under the nilpotent part of
. We construct an action of the nilpotent part
of
on their lattice counterparts, and embed the lattice variables in a
, coinduced from a quantum version of the principal commutative subalgebra, which is defined using the identification of
with its dual algebra. 相似文献
10.
We use the recursion method to calculate the vibrational density of states
of site percolation clusters slightly above the percolation threshold. It is found that
is proportional to at long wavelengths. At shorter length scales,
is proportional to
, with the fraction dimension
. The cross-over from phonon to fraction regime is characterized by a rapid rise in
in agreement with effective medium calculations. 相似文献
11.
G. Dietz K. Richter F. Stein H. C. Schäfer 《Zeitschrift für Physik B Condensed Matter》1990,81(2):223-228
Dependent on
is produced through electrodeposition in three modifications: microcrystalline if
, amorphous if
and in a mixed state containing both components if
. The interpretation of results of large and small angle X-ray scattering, of measurements of the coercivity and of the mechanical density shows that the three modifications consist of two phases. The structure of the grain boundary phase in the microcrystalline alloys differs considerably from that of the amorphous phase. This arises from the dependence of the atomic volume on the average phosphorus content
. The volume fraction of the crystalline component decreases with increasing
up to
. But even in alloys revealing X-ray patterns without any peaks coming from crystalline particles small angle X-ray scattering indicates the existence of metal-rich inclusions occupying some percent of the total volume. 相似文献
12.
S. L. Woronowicz 《Communications in Mathematical Physics》1972,28(3):221-235
Let
be aC*-algebra and
be an opposite algebra. Notions of exact andj-positive states of
are introduced. It is shown, that any factor state of
can be extended to a pure exactj-positive state
of
. The correspondence
generalizes the notion of the purifications map introduced by Powers and Størmer. The factor states 1 and 2 are quasi-equivalent if and only if their purifications
and
are equivalent. 相似文献
13.
Fukui Guo Yufeng Zhang Qingyou Yan 《International Journal of Theoretical Physics》2004,43(4):1139-1146
A new simple method for obtaining integrable hierarchies of soliton equations is proposed. First of all, a new loop algebra
is constructed, whose commutation operation is clear as that in loop algebra
. Second, by making use of the Tu scheme, many of integrable hierarchies with multicomponent potential functions can be produced. As a specific application of our method, a multicomponent AKNS hierarchy is obtained. Finally, an expanding loop algebra
of the loop algebra
is constructed. Taking advantage of
above, a type of integrable coupling system of the multicomponent AKNS hierarchy is worked out. 相似文献
14.
V. Gaftoi J. Lopez-Bonilla G. Ovando 《International Journal of Theoretical Physics》1999,38(3):939-943
Weert found a superpotential
for the bounded part of the Maxwelltensor
associatedto the Lienard–Wiechert field. Here we obtain afourth-rank generator
for the superpotential
. 相似文献
15.
We consider solutions to the Dirac equation in the presence of an external axial vector potential
coupled to the spinor field psi through the interaction term
. There turn out to be no bound-state energies in this system consistent with a normalizable wave function. 相似文献
16.
We study analogues of the Yangian of the Lie algebra
for the other classical Lie algebras
and
. We call them twisted Yangians. They are coideal subalgebras in the Yangian of
and admit homomorphisms onto the universal enveloping algebras U(
) and U(
) respectively. In every twisted Yangian we construct a family of maximal commutative subalgebras parametrized by the regular semisimple elements of the corresponding classical Lie algebra. The images in U(
) and U(
) of these subalgebras are also maximal commutative. 相似文献
17.
We show that the Ashtekar-Isham extension
of the configuration space of Yang-Mills theories
is (topologically and measure-theoretically) the projective limit of a family of finite dimensional spaces associated with arbitrary finite lattices.These results are then used to prove that
is contained in a zero measure subset of
with respect to the diffeomorphism invariant Ashtekar-Lewandowski measure on
. Much as in scalar field theory, this implies that states in the quantum theory associated with this measure can be realized as functions on the extended configuration space
. 相似文献
18.
Pin-Zhen Bi 《Zeitschrift fur Physik C Particles and Fields》1991,52(1):105-109
The ellipsoidal bag model is used to describe heavy quark systems such asQ
,Q
g andQ
2
. Instead of two step model, these states are described by an uniform picture. The potential derived from the ellipsoidal bag forQ
is almost equivalent to the Cornell potential. For aQ
2
system with large quark pair separation, an improvement of 70 MeV is obtained comparing with the spherical bag. 相似文献
19.
We construct a non-commutative *-algebra
which is a quantum deformation of the algebra of continuous functions on the closed unit disc
.
is generated by the Toeplitz operators on a suitable Hilbert space of holomorphic functions onU.Supported in part by the National Science Foundation under grant DMS/PHY 88-16214 相似文献
20.
The sequence of Jordan algebras
, whose elements are the 3×3 Hermitian matrices over the division algebras , , , and
, is considered. These algebras are naturally related to supersymmetric structures in space-time dimensions of 3, 4, 6, and 10, as the Lorentz groups in these dimensions can be expressed in a unified way as a subgroup of the structure group of the Jordan algebras
. The generators of the complete structure group and the automorphism group can be separated into bosonic and fermionic generators, depending on their transformation properties under the Lorentz subgroup. A peculiar connection between these fermionic generators and the supersymmetry generators of the superstring action is introduced and discussed. 相似文献