379 research outputs found
Normal origamis of Mumford curves
An origami (also known as square-tiled surface) is a Riemann surface covering
a torus with at most one branch point. Lifting two generators of the
fundamental group of the punctured torus decomposes the surface into finitely
many unit squares. By varying the complex structure of the torus one obtains
easily accessible examples of Teichm\"uller curves in the moduli space of
Riemann surfaces. The p-adic analogues of Riemann surfaces are Mumford curves.
A p-adic origami is defined as a covering of Mumford curves with at most one
branch point, where the bottom curve has genus one. A classification of all
normal non-trivial p-adic origamis is presented and used to calculate some
invariants. These can be used to describe p-adic origamis in terms of glueing
squares.Comment: 21 pages, to appear in manuscripta mathematica (Springer
Introduction to Categories and Categorical Logic
The aim of these notes is to provide a succinct, accessible introduction to
some of the basic ideas of category theory and categorical logic. The notes are
based on a lecture course given at Oxford over the past few years. They contain
numerous exercises, and hopefully will prove useful for self-study by those
seeking a first introduction to the subject, with fairly minimal prerequisites.
The coverage is by no means comprehensive, but should provide a good basis for
further study; a guide to further reading is included. The main prerequisite is
a basic familiarity with the elements of discrete mathematics: sets, relations
and functions. An Appendix contains a summary of what we will need, and it may
be useful to review this first. In addition, some prior exposure to abstract
algebra - vector spaces and linear maps, or groups and group homomorphisms -
would be helpful.Comment: 96 page
The Physics of Mixing: and in the Chiral Quark Model
We compute the parameter and the mass difference of the system by means of the chiral quark model. The
chiral coefficients of the relevant and chiral
lagrangians are computed via quark-loop integration. We include the relevant
effects of one-loop corrections in chiral perturbation theory. The final result
is very sensitive to non-factorizable corrections of coming
from gluon condensation. The size of the gluon condensate is determined by
fitting the experimental value of the amplitude . By
varying all the relevant parameters we obtain
We evaluate within the model the long-distance contributions to
induced by the double insertion of the chiral lagrangian and
study the interplay between short- and long-distance amplitudes. By varying all
parameters we obtain Finally, we investigate the phenomenological constraints on
the Kobayashi-Maskawa parameter Im entering the determination of
.Comment: 31 pages, Latex file including 7 eps figures. Revised version to
appear in Nucl. Phys.
Clinical Evaluation of a Telemedically Linked Intraoral Drug Delivery System
The miniaturized intraoral drug delivery system BuccalDose is composed of a replaceable cartridge which is worn in a removable prosthesis and an external base station for telemedical therapy monitoring. The system has now been tested for the first time with Parkinson\u2019s disease (PD) patients. The study evaluated the usability of the entire system, the functionality of the telemedical transmission path and the functionality of the cartridge, which uses an osmotic pumping principle to release a liquid drug formulation to the buccal mucosa. The BuccalDose system was generally considered to be easy to handle, even with movement disorders, up to a mild-moderate disease stage. In addition, the obtained in vivo release rates of the cartridges confirmed the previously achieved in vitro release behavior
A series of coverings of the regular n-gon
We define an infinite series of translation coverings of Veech's double-n-gon
for odd n greater or equal to 5 which share the same Veech group. Additionally
we give an infinite series of translation coverings with constant Veech group
of a regular n-gon for even n greater or equal to 8. These families give rise
to explicit examples of infinite translation surfaces with lattice Veech group.Comment: A missing case in step 1 in the proof of Thm. 1 b was added. (To
appear in Geometriae Dedicata.
Non-factorizable contribution in nonleptonic weak interactions of K mesons
Two pion decays of K mesons, K_L-K_S mass difference, two photon and the
Dalitz decays of K_L are studied systematically by assuming that their
amplitude is given by a sum of factorizable and non-factorizable ones. The
former is estimated by using a naive factorization while the latter is assumed
to be dominated by dynamical contributions of various hadron states.Comment: 23 pages,1 figur
Over-additive increase of bacterial mutations by combined action of ultraviolet light and alkylation
Completing NLO QCD Corrections for Tree Level Non-Leptonic Delta F = 1 Decays Beyond the Standard Model
In various extensions of the Standard Model (SM) tree level non-leptonic
decays of hadrons receive contributions from new heavy gauge bosons and
scalars. Prominent examples are the right-handed W' bosons in left-right
symmetric models and charged Higgs (H^\pm) particles in models with extended
scalar sector like two Higgs doublet models and supersymmetric models. Even in
the case of decays with four different quark flavours involved, to which
penguin operators cannot contribute, twenty linearly independent operators,
instead of two in the SM, have to be considered. Anticipating the important
role of such decays at the LHCb, KEKB and Super-B in Rome and having in mind
future improved lattice computations, we complete the existing NLO QCD formulae
for these processes by calculating O(alpha_s) corrections to matching
conditions for the Wilson coefficients of all contributing operators in the
NDR-\bar{MS} scheme. This allows to reduce certain unphysical scale and
renormalization scheme dependences in the existing NLO calculations. Our
results can also be applied to models with tree-level heavy neutral gauge boson
and scalar exchanges in Delta F = 1 transitions and constitute an important
part of NLO analyses of those non-leptonic decays to which also penguin
operators contribute.Comment: 24 pages, 6 figure
Estimate of B(K -> pi nu nubar) from Standard Model fits to lambda_t
We estimate B(K -> pi nu nubar) in the context of the Standard Model by
fitting for lambda_t = Vtd x V*ts of the `kaon unitarity triangle' relation. We
fit data from epsilon_K, the CP-violating parameter describing K-mixing, and
a_{psi K}, the CP-violating asymmetry in B -> J/psi K decays. Our estimate is
independent of the CKM matrix element Vcb and of the ratio of Bs to Bd mixing
frequencies. The measured value of B(K+ -> pi+ nu nubar) can be compared both
to this estimate and to predictions made from the ratio of B mixing
frequencies.Comment: 8 pages, including 6 figures. v3 includes an expanded discussion of
correlations between SM inputs to the lambda_t fit, clarifies the discussion
of the independence of this result from the ratio of B mixing frequencies,
includes minor updates to the values of SM input parameters, and includes
some new and some updated reference
Splittings of generalized Baumslag-Solitar groups
We study the structure of generalized Baumslag-Solitar groups from the point
of view of their (usually non-unique) splittings as fundamental groups of
graphs of infinite cyclic groups. We find and characterize certain
decompositions of smallest complexity (`fully reduced' decompositions) and give
a simplified proof of the existence of deformations. We also prove a finiteness
theorem and solve the isomorphism problem for generalized Baumslag-Solitar
groups with no non-trivial integral moduli.Comment: 20 pages; hyperlinked latex. Version 2: minor change
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