Related papers: The Rest-Frame Instant Form and Dirac Observables …
The properties of a stationary massless string endowed with intrinsic spin are discussed. The spacetime is Minkowskian geometrically but the topology is nontrivial due to the horizon located on the surface $r=0$, similar with Rindler's…
We analyze the dynamical equations obeyed by a classical system with position-dependent mass. It is shown that there is a non-conservative force quadratic in the velocity associated to the variable mass. We construct the Lagrangian and the…
We address nonperturbative dynamics of the two-dimensional bosonic and supersymmetric $\mathbb{C}P^{N-1}$ models for general $N$ by developing new tools directly on $\mathbb{R}^2$. The analysis starts with a new formulation of instantons…
In this paper, we determine the relativistic bound-state solutions for the charged (DO) Dirac oscillator in a rotating frame in the Bonnor-Melvin-Lambda spacetime in $(2+1)$-dimensions, where such solutions are given by the two-component…
We examine the leading order corrections to the Nambu effective action for the motion of a cosmic string, which appear at fourth order in the ratio of the width to radius of curvature of the string. We determine the numerical coefficients…
Noncommutativity in an open bosonic string moving in the presence of a background Neveu-Schwarz two-form field $B_{\mu \nu}$ is investigated in a conformal field theory approach, leading to noncommutativity at the boundaries. In contrast to…
We study profiles and gauge invariant observables of classical solutions corresponding to a constant magnetic field on a torus in open string field theory. We numerically find that the profile is not discontinuous on the torus, although the…
We propose a method of projecting the quantum states from a state space of a given geometry into another state space generated by a different geometry, taking care on the correct normalization which is crucial in interpreting the quantum…
We obtain exact solution of the Dirac equation for a charged particle with position-dependent mass in the Coulomb field. The effective mass of the spinor has a relativistic component which is proportional to the square of the Compton…
In a previous paper we provided a consistent quantization of open strings ending on D-branes with a background $B$ field. In this letter, we show that the same result can also be obtained using the more traditional method of Dirac's…
At the classical level we study open bosonic strings. A generic description of string self-interactions localized at string ends is given. Self-interactions are characterized by two dimensionless coupling constants. The model is rewritten…
The dynamics of a probe brane in a given gravitational background is governed by the Dirac-Born-Infeld action. The corresponding open string metric arises naturally in studying the fluctuations on the probe. In Gauge-String duality, it is…
Using the Polchinski-Strominger effective string theory in covariant gauge, we compute the mass of a rotating string in D dimensions with large angular momenta J, in one or two planes, in fixed ratio, up to and including first subleading…
Observables 'are observed' whereas beables just 'are'. This gives beables more scope in the cosmological and quantum domains. Both observables and beables are entities that form 'brackets' with 'the constraints' that are 'equal to' zero. We…
In this paper we consider a class of generalizations of Schnabl's solution of open bosonic string field theory obtained by replacing the wedge state by an arbitrary combination of wedge states. We find that under a few modest conditions…
Classical and quantum solutions for the relativistic straight-line string with arbitrary dependence on the world surface curvature are obtained. They differ from the case of the usual Nambu-Goto interaction by the behaviour of the Regge…
We consider a relativistic quantum model of confined massive spinning quarks and antiquarks which describes leading Regge trajectories of mesons. The quarks are described by the Dirac equations and the gluon contribution is approximated by…
We investigate an alternative compactification of extra dimensions using local cosmic string in the Brans-Dicke gravity framework. In the context of dynamical systems it is possible to show that there exist a stable field configuration for…
We show that there exist a nontrivial contribution on the Witten covariant phase space when the Gauss-Bonnet topological term is added to the Dirac-Nambu Goto action describing strings, because of the geometry of deformations is modified,…
In General Relativity, cosmic strings are well known to produce a static, locally flat spacetime with a wedge removed. If the tension exceeds a critical value, the deficit angle becomes larger than $ 2\pi $, leading to a compact exterior…