4,602 research outputs found
The Neron-Severi group of a proper seminormal complex variety
We prove a Lefschetz (1,1)-Theorem for proper seminormal varieties over the
complex numbers. The proof is a non-trivial geometric argument applied to the
isogeny class of the Lefschetz 1-motive associated to the mixed Hodge structure
on H^2.Comment: 16 pages; Mathematische Zeitschrift (2008
Experimental demonstration of Shor's algorithm with quantum entanglement
Shor's powerful quantum algorithm for factoring represents a major challenge
in quantum computation and its full realization will have a large impact on
modern cryptography. Here we implement a compiled version of Shor's algorithm
in a photonic system using single photons and employing the non-linearity
induced by measurement. For the first time we demonstrate the core processes,
coherent control, and resultant entangled states that are required in a
full-scale implementation of Shor's algorithm. Demonstration of these processes
is a necessary step on the path towards a full implementation of Shor's
algorithm and scalable quantum computing. Our results highlight that the
performance of a quantum algorithm is not the same as performance of the
underlying quantum circuit, and stress the importance of developing techniques
for characterising quantum algorithms.Comment: 4 pages, 5 figures + half-page additional online materia
Lepton flavor violation at linear collider experiments in supersymmetric grand unified theories
Lepton flavor violation at linear collider experiments is discussed. We show
that detectable lepton flavor violation could occur through scalar lepton pair
production and decay in the supersymmetric SU(5) grand unified theory in spite
of the stringent present experimental constraints by rare process searches.
Possible cross sections about 40fb for an e+e- collider and 280fb for an e-e-
collider are illustrated.Comment: 12 pages, including 3 figures, REVTeX, eps
Electric Dipole moments of charged leptons and lepton flavor violating interactions in the general two Higgs Doublet model
We calculate the electric dipole moment of electron using the experimental
result of muon electric dipole moment and upper limit of the BR(\mu -->
e\gamma) in the framework of the general two Higgs doublet model. Our
prediction is 10^{-32} e-cm, which lies in the experimental current limits.
Further, we obtain constraints for the Yukawa couplings \bar{\xi}^{D}_{N,\tau
e} and \bar{\xi}^{D}_{N,\tau\mu}. Finally we present an expression which
connects the BR(\tau\to \mu\gamma) and the electric dipole moment of
\tau-lepton and study the relation between these physical quantities.Comment: 8 pages, 4 Figures (required epsf sty
Distribution of amiodarone and desethylamiodarone in a patient with acute myocardial infarction after intravenous administration
The autopsy tissues concentration of amiodarone and desethylamiodarone of a man with acute myocardial infarction treated acutely with intravenous amiodarone is reported. Our data indicate that amiodarone is quickly distributed into all highly perfused tissues after intravenous administration with a high amiodarone/desethylamiodarone ratio. We also report here the autopsy case of a woman who died after 30 days of oral therapy with amiodarone. The increase in heart/plasma ratio of amiodarone and desethylamiodarone concentrations and the decrease in amiodarone/desethylamiodarone ratio after one month of therapy could explain the latency in the antiarrhythmic action of the drug
Native cattle breeds of Southern Italy: karyological profile
Italian typical products of animal origin are strictly linked to native breeds. Their protection requires control of their reproductive and productive abilities. Hence the need for karyological studies to identify subjects with chromosome abnormalities linked to hypofertility or sterility. We report the results of karyological analyses carried out from January 2008 to December 2008 on 145 cattle of native breeds (Agerolese, Cinisara, Modicana and Podolica) reared in Southern Italy so as to evaluate and characterize the presence of chromosome abnormalities in subjects with normal phenotypes. Besides the 128 karyologically normal subjects (2n=60, XY and 2n=60, XX), 17 were carriers of rob (1;29) and one male was a carrier of cellular chimerism 2n=60, XX/XY. According to our data there is a high frequency of rob (1;29) in Cinisara and Podolica breeds while in Agerolese there was only one case of rob (1;29) and none in Modicana
Lamb shift in muonic helium ion
The Lamb shift (2P_{1/2}-2S_{1/2}) in the muonic helium ion (mu ^4_2He)^+ is
calculated with the account of contributions of orders alpha^3, alpha^4,
alpha^5 and alpha^6. Special attention is given to corrections of the electron
vacuum polarization, the nuclear structure and recoil effects. The obtained
numerical value of the Lamb shift 1379.028 meV can be considered as a reliable
estimate for the comparison with experimental data.Comment: 18 pages, 11 figure
Detecting Physics At The Post-GUT And String Scales By Linear Colliders
The ability of linear colliders to test physics at the post-GUT scale is
investigated. Using current estimates of measurements available at such
accelerators, it is seen that soft breaking masses can be measured with errors
of about (1-20)%. Three classes of models in the post-GUT region are examined:
models with universal soft breaking masses at the string scale, models with
horizontal symmetry, and string models with Calabi-Yau compactifications. In
each case, linear colliders would be able to test directly theoretical
assumptions made at energies beyond the GUT scale to a good accuracy,
distinguish between different models, and measure parameters that are expected
to be predictions of string models.Comment: Latex, 21 pages, no figure
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