Neutrino Masses and Conformal Electro-Weak Symmetry Breaking

Dimensional transmutation in classically conformal invariant theories may explain the electro-weak scale and the fact that so far nothing but the Standard Model (SM) particles have been observed. We discuss in this paper implications of this type of symmetry breaking for neutrino mass generation.Comment: 23 pages, 4 figures (one new figure), journal versio

Quantum Boltzmann equations for electroweak baryogenesis including gauge fields

We review and extend to include the gauge fields our derivation of the semiclassical limit of the collisionless quantum transport equations for the fermions in presence of a CP-violating bubble wall at a first order electroweak phase transition. We show how the (gradient correction modified) Lorenz-force appears both in the Schwinger-Keldysh approach and in the semiclassical WKB-treatment. In the latter approach the inclusion of gauge fields removes the apparent phase reparametrization dependence of the intermediate calculations. We also discuss setting up the fluid equations for practical calculations in electroweak baryogenesis including the self-consistent (hyper)electric field and the anomaly.Comment: 15 pages, talk presented by Kimmo Kainulainen at COSMO-01, Rovaniemi, Finland, 09/200

Kinetic approach to electroweak baryogenesis

After a short review of baryogenesis mechanisms, we focus on the charge transport mechanism at the electroweak scale, effective at strong electroweak phase transitions. Starting from the one-loop Schwinger-Dyson equations for fermions coupled to bosons, we present a derivation of the relevant kinetic equations in the on-shell and gradient approximations, relevant for the thick wall baryogenesis regime. We then discuss the CP-violating source from the semiclassical force in the flow term, and compare it with the source arising in the collision term of the kinetic equation. Finally, we summarize the results concerning the chargino mediated baryogenesis in the Minimal Supersymmetric Standard Model.Comment: 13 pages, 6 figures. Invited talk at the International Workshop "Strong and Electroweak Matter 2002", October 2-5, 2002 Heidelberg, German

Some aspects of collisional sources for electroweak baryogenesis

We consider the dynamics of fermions with a spatially varying mass which couple to bosons through a Yukawa interaction term and perform a consistent weak coupling truncation of the relevant kinetic equations. We then use a gradient expansion and derive the CP-violating source in the collision term for fermions which appears at first order in gradients. The collisional sources together with the semiclassical force constitute the CP-violating sources relevant for baryogenesis at the electroweak scale. We discuss also the absence of sources at first order in gradients in the scalar equation, and the limitations of the relaxation time approximation.Comment: 12 pages, 4 figures, talk presented by Tomislav Prokopec at COSMO-01, Rovaniemi, Finland, 09/2001 references added, minor changes in sections 5.3 and

Quantitative Considerations about the Semantic Relationship of Entities in a Document Corpus

Providing suggestions for internet-users is an important task nowadays. So for example, when we enter a search string into the Google interface, it suggests further terms, based on previously formulated queries from other users having used the search engine before. In the context of an entity based search engine, entity-suggestion is also a very important task, when specifying the entities by the user. Additionally, this feature can also be utilized to suggest further entities, which are somehow related to already specified entities. If the suggestions are eligible the user can very quickly formulate his search desire. If the suggestions are based on the search corpus itself, new and previously unknown relationships between entities can be discovered along the way. The aim of this paper is a quantitative analysis of relationships between entities in a big document corpus under the aspect of providing suggestions for entities in real time