A tachyonic extension of the stringy no-go theorem

We investigate the tachyon-dilaton-metric system to study the "graceful exit" problem in string theoretic inflation, where tachyon plays the role of the scalar field. From the phase space analysis, we find that the inflationary phase does not smoothly connect to a Friedmann-Robertson-Walker (FRW) expanding universe, thereby providing a simple tachyonic extension of the recently proved stringy no-go theorem.Comment: TeX file (PHYZZX), 10 pages, change in the title, many changes in the text (the version to appear in Phys. Rev. D

Pion-nucleon charge-exchange scattering and scaling of the differential cross section

Bounds on slope and curvature of absorptive inelastic differential cross section are deduced. It is found that the differential cross section for π-p→π0n and π-p→ηn scale remarkably over a wide range of energy

Consequences of a modified charmed current

We study the inclusive production of D+ and diffractive production of D∗ + in neutrino scattering using the V + A form of the charm current. Cross sections for production of D+ and D∗+ are of the order of 10-35 cm2/GeV3 and 1038 cm2/GeV3, respectively

Production of mesons with new flavor in e<SUP>+</SUP>e<SUP>-</SUP> collisions

Cross sections for production of BB, B&#8727; B+B&#8727; B, and B&#8727;B&#8727; mesons (carrying b-quark quantum numbers) in e+e- annihilation are estimated and differential cross sections are evaluated. The cross sections for e+e-&#8594;e+e-&#951;b, e+e-&#8594;e+e-&#967;b, and e+e-&#8594;e+e-BB are computed in the equivalent-photon approximation

Charmed-particle production in neutrino scattering

Inclusive production of charmed vector mesons has been studied in high-energy neutrino scattering. The cross sections calculated in the triple-Regge limit are of the order of 10-41 cm2/GeV3. The production mechanism in the central region is also discussed

Path-integral formulation of the theory of loops and strings

We present a path-integral formulation of the theory of loops and strings with scalar "quarks" using the constrained Hamiltonian formalism and the properties of canonical transformation

A path integral formulation of the theory of loops

We present a path integral formulation of the theory of loops using constrained hamiltonian formalism