1531218
THE SPACETIME SUPERALGEBRAS IN A MASSIVE IIA BACKGROUND VIA BRANE PROBES
Abstract We derive the spacetime superalgebras explicitly from “test” p-brane actions in a D-8-brane (i.e. a massive IIA ) background to the lowest order in θ via canonical formalism, and show that the forms of the superalgebras are the same as those in all the other D-brane (i.e. massless IIA) backgrounds, that is, they are indifferent to the presence of the Chern-Simons terms which are proportional to the mass and added to the D-brane actions in the case of massive IIA backgrounds. Thus, we can say that all the D-brane background solutions including a D-8-brane are on equal footing from the viewpoint of the superalgebras via brane probes. We also deduce from the algebra all the previously known 1/4 supersymmetric intersections of a p-brane or a fundamental string with a D-8-brane, as the supersymmetric “gauge fixings” of the test branes in the D-8-brane background.
14293872
The mass formula for a fundamental string as a BPS solution of a D-brane's worldvolume
Abstract We propose a (generalized) “mass formula” for a fundamental string described as a BPS solution of a D-brane's worldvolume. The mass formula is obtained by using the Hamiltonian density on the worldvolume, based on transformation properties required for it. Its validity is confirmed by investigating the cases of point charge solutions of D-branes in a D-8-brane (i.e. curved) background, where the mass of each of the corresponding strings is proportional to the geodesic distance from the D-brane to the point parametrized by the (regularized) value of a transverse scalar field. It is also shown that the mass of the string agrees with the energy defined on the D-brane's worldvolume only in the flat background limit, but the agreement does not always hold when the background is curved.
9039443
A QUANTUM ANALYSIS ON RECOMBINATION OF D-BRANES AND ITS IMPLICATIONS FOR AN INFLATION MODEL
A quantum-mechanical technique is used within the framework of U(2) super-Yang-Mills theory to investigate processes after recombination of two D-p-branes at one angle. Two types of initial conditions are considered, one of which with $p=4$ is a candidate of inflation mechanism. It is shown that the branes' shapes come to have three extremes due to localization of tachyon condensation. ``Pair-creations'' of open stings connecting the recombined branes is also observed. The appearance of closed strings is also discussed; the decaying branes are shown to radiate non-vanishing gravitational wave, which may be interpreted as evidence of closed string appearance. A few speculations are also given on implications of the above phenomena for an inflation model.
9070559
Various Supersymmetric Brane Configurations from Superalgebras in Many Types of M-Brane Backgrounds
We derive superalgebras in many types of supersymmetric M-brane backgrounds. The backgrounds examined here include the cases of the M-wave and the M-Kaluza-Klein monopole. On the basis of the obtained algebras, we deduce all the supersymmetric nonorthogonal intersections of the M-Kaluza-Klein monopole and the M-5-brane at angles, most of which were previously unexamined. In addition, we present a new worldvolume soliton on the M-5-brane in the M-5-brane background which is interpreted as a certain intersection of three M-5-branes. The soliton has 1/8 supersymmetry, which can easily be confirmed by using the superalgebra. tsato@icrr.u-tokyo.ac.jp
17323083
On M-9-branes and their dimensional reductions
Abstract The M-9-brane Wess-Zumino action is constructed, and by using it, consistency of the relation of p-branes for p ≥ 8, suggested on the basis of superalgebra, is discussed.
14541880
D-brane dynamics and creations of open and closed strings after recombination
Abstract A quantum-mechanical technique is used within the framework of U(2) super-Yang–Mills theory to investigate what happens in the process after recombination of two D p -branes at one angle. Two types of initial conditions are considered, one of which with p =4 is a candidate of inflation mechanism. It is observed that the branes' shapes come to have three extremes due to localization of tachyon condensation. Furthermore, open string pairs connecting the decaying D-branes are shown to be created; most part of the released energy is used to create them. It also strongly suggests that creation of closed strings happens afterward. Closed strings as gravitational radiation from the D-branes are also shown to be created. A few speculations are also given on implications of the above phenomena for an inflation model.
118668452
Neutrino-induced forward meson-production reactions in nucleon resonance region
As a first step toward developing a reaction model that enables a comprehensive description of neutrino-nucleon reactions in the nucleon resonance region, we have applied for the first time a dynamical coupled-channels model, which successfully describes \pi N, \gamma N --> \pi N, \eta N, \pi \pi N, K\Lambda, K\Sigma reactions up to W = 2 GeV, to predict the neutrino-induced meson-production reactions with \Delta S = 0 at the forward angle limit. This has been achieved by relating the divergence of the axial-current matrix elements at Q^2 = 0 to the \pi N --> X reaction amplitudes through the PCAC hypothesis. We present the contributions from each of the \pi N, \eta N, \pi \pi N, K\Lambda, K\Sigma channels to the F_2 structure function at Q^2 --> 0 limit up to W = 2 GeV.