15345099
Colliding Waves on a Brane, the Big Bounce and Reconnection
We present a time-dependent solution of the Nambu-Goto action which represents two colliding waves moving at the speed of light. This solution can be decomposed into two distinct regions with different geometries corresponding to shrinking or expanding brane universe and two colliding branes. The former describes the Big Bounce without singularity while the latter describes that two branes collide and reconnect to each other. The colliding brane region has a signature change. Classical dynamics of a massive particle on the brane is studied through the geodesics.
118864807
Particle with non-Abelian charge: classical and quantum
We study the action for a non-Abelian charged particle in a non-Abelian background field in the worldline formalism, described by real bosonic variables, leading to the well known equations given by Wong. The isospin parts in the action can be viewed as the Lagrange multiplier term corresponding to a non-holonomic constraint restricting the isospins to be parallel transported. The path integration is performed over the isospin variables and as a result, the worldlines turn out to be constrained by the classical solutions for the isospins. We derive a wave equation from the path integral, constructed as the constrained Hamiltonian operator acting on the wave function. The operator ordering corresponding to the quantum Hamiltonian is found and verified by the inverse Weyl transformation.
10700275
One-loop effective brane action
The one-loop effective action for a p brane embedded in a D = p+2 Minkowski spacetime in the static gauge is calculated. Rescaling the quantum fluctuation by (−g0)1/2 evaluated on the background brane leads to the one-loop effective action expressed only in terms of infrared and ultraviolet divergent geometric scalars. After the infrared divergences are absorbed into the quantum fluctuation, there remains the finite number of ultraviolet divergences. This implies that the D = p+2 Poincare symmetry and the D = p+1 general coordinate invariance are preserved in one-loop order.
15173498
Mass matrices and their renormalization
We obtain explicitly the renormalization group equations for the quark mass matrices in terms of a set of rephasing invariant parameters. For a range of assumed high energy values for the mass ratios and mixing parameters, they are found to evolve rapidly and develop hierarchies as the energy scale decreases. To achieve the experimentally observed high degree of hierarchy, however, the introduction of new models with specific properties becomes necessary.
19450734
Rephasing invariant parametrization of flavor mixing matrices
The three-flavor mixing matrix can be parameterized by the rephasing invariants {gamma}{sub ijk}=V{sub 1i}V{sub 2j}V{sub 3k}. This formulation brings out the inherent symmetry of the problem and has some appealing features. Examples illustrating the parametrization and applications to quark mixing are presented.
119278346
Estimation of the large order behavior of the plaquette
Abstract The universality of vacuum condensate can be exploited to relate the infrared renormalon caused large order behaviors of different processes. As an application the normalization constant of the large order behavior of the average plaquette is estimated using the Adler function.
122441494
KRICHEVER — NOVIKOV BASES FOR THE BOSONIC STRING
The global operator formalism proposed recently by Krichever and Novikov using meromorphic tensor fields on general Riemann surfaces of arbitrary genus is applied to the bosonic string. The well-known Green's function of the scalar boson fields is obtained in a simple manner from the spectral representation. Proof of Wick's theorem is also given.
122518339
Static brane solutions stabilized by nonlinear bulk scalar dynamics
We study a nonlinear sigma-model-like theory of a bulk scalar field coupled to the five-dimensional Einstein gravity with a negative cosmological constant. We determine the structure of the non-factorizable spacetime which our Minkowskian brane bounds, when the pressure in the extra dimension is proportional to the energy density of the scalar field as with a constant ?5. With these static solutions clarified by the parameter ?5, we fix the size of the extra dimension in terms of the bulk and brane potentials of the scalar field, imposing the stability condition in the cases of the 2-branes. The hierarchy problem is discussed in their Randall?Sundrum-like limit, and one of the static solutions obtained in the case of a strong bulk potential ?5 < 0 is interpreted as a thick 1-brane model.
118939493
The final fate of the rolling tachyon
We propose an alternative interpretation of the boundary state for the rolling tachyon, which may depict the time evolution of unstable D-branes in string theory. Splitting the string variable in the temporal direction into the classical part, which we may call ``time and the quantum one, we observe the time dependent behaviour of the boundary. Using the fermion representation of the rolling tachyon boundary state, we show that the boundary state correctly describes the time-dependent decay process of the unstable D-brane into a S-brane at the classical level.
118161656
The Entropy of the BTZ Black Hole and AdS/CFT Correspondence
We construct an action, which governs the dynamics of the Ba\~nados-Teitelboim-Zanelli (BTZ) black hole and perform the canonical quantization. The quantum action is given by a $SL(2,R)$ Wess-Zumino-Witten model on the boundary coupled to the classical anti-de Sitter background, representing a massless BTZ black hole. The coupling, determined by a one-cocyle condition, is found to give dominant contribution to the central charge of Virasoro algebra. The entropy of the BTZ black hole is discussed from the point view of the AdS/CFT correspondence and an explanation is given to the puzzle of black hole entropy in the BTZ case. The BTZ black hole is a quantum object and the BTZ black hole with finite mass should be considered as a quantum excitation of the massless one.