ADVANCED SUMMER SCHOOL IN PHYSICS 2009: Frontiers in Contemporary Physics
1287(2010); http://dx.doi.org/10.1063/1.3507423View Description Hide Description
Supersymmetric quantum mechanics (SUSY QM) is a powerful tool for generating new potentials with known spectra departing from an initial solvable one. In these lecture notes we will present some general formulae concerning SUSY QM of first second order for one‐dimensional arbitrary systems, we will illustrate the method through the trigonometric Pöschl‐Teller potentials. Some intrinsically related subjects, as the algebraic structure inherited by the new Hamiltonians and the corresponding coherent states will be analyzed. The technique will be as well implemented for periodic potentials, for which the corresponding spectrum is composed of allowed bands separated by energy gaps.
1287(2010); http://dx.doi.org/10.1063/1.3507422View Description Hide Description
This is a brief account of the short course in Cosmology presented at the Advanced Summer School of Physics 2009 of the Physics Department at CINVESTAV‐IPN (Mexico). The purpose of the course was two fold: to draw the attention of Physics students to Cosmology, and to give a concise description of modern Cosmology and of its two main challenges, Dark Matter and Dark Energy.
1287(2010); http://dx.doi.org/10.1063/1.3507424View Description Hide Description
We provide a brief introduction on string compactifications for non‐experts. The prediction of critical string theory to have a ten‐dimensional space‐time gives a rich background to answer fundamental questions in theoretical physics. From the Calabi‐Yau compactification to recent flux compactification models, we discuss the attempts made to construct a consistent and realistic effective four‐dimensional theory.
1287(2010); http://dx.doi.org/10.1063/1.3507425View Description Hide Description
The resonant control techniques are susceptible of assisting error accumulation in quantum control protocols consisting of large sequences of external fields. It is shown that for some algorithms the information about the final state of the system may be partially or completely lost. Non trivial operations in the non resonant regime are also discussed.
1287(2010); http://dx.doi.org/10.1063/1.3507426View Description Hide Description
After a short overview of the basic mathematical structure of quantum mechanics we analyze the Schrödinger’s antinomic example of a living and dead cat mixed in equal parts. Superpositions of Glauber kets are shown to approximate such macroscopic states. Then, two‐level atomic states are used to construct mesoscopic kittens as appropriate linear combinations of angular momentum eigenkets for Some general comments close the present contribution.
1287(2010); http://dx.doi.org/10.1063/1.3507428View Description Hide Description
We report the observation of spatial biphoton correlation in spontaneous parametric down conversion. The optical bench includes a type‐I BBO crystal of effective length 2 mm, pumped by a 100 mW violet laser diode centered at 405.38 nm. Photon pairs are created with degenerate wavelength ≈810.76 nm. Once the horizontal counting rates have been measured, a simple geometrical recipe is shown to be useful in calculating bounds for the width of vertical counting rates. The spatial correlation between idler and signal photons is illustrated with a coincidence distribution of the coordinate pair with the idler (signal) detector position in horizontal scan.
1287(2010); http://dx.doi.org/10.1063/1.3507429View Description Hide Description
1287(2010); http://dx.doi.org/10.1063/1.3507431View Description Hide Description
We show how neutrino data can be used in order to constrain the free parameters of possible extensions to the standard model of elementary particles (SM). For definiteness, we focus in the recently proposed unparticle scenario. We show that neutrino data, in particular the MUNU experiment, can set stronger bounds than previous reported limits in the scale dimension parameter for certain region we compute the sensitivity of future neutrino experiments to unparticle physics such as future neutrino‐electron scattering detectors, coherent neutrino‐nuclei scattering as well as the ILC. In particular, we show that the measurement of coherent reactor neutrino scattering off nuclei provide a good sensitivity to the couplings of unparticle interaction with neutrinos and quarks. Finally our results are compared with the current astrophysical limits.
1287(2010); http://dx.doi.org/10.1063/1.3507420View Description Hide Description
The possibilities that offer the photo thermal techniques to determine the thermal properties widely have been demonstrated [1,2]. From these techniques, photo acoustic and photo pyrelectric has turned out to be very useful in studies of biological materials, which frequently present many difficulties due to a high dispersion to the light and structures that vary with the depth. In this work we used the photo acoustic technique in the configuration of open cell and the photo pyrelectric technique, to determine the thermal properties of natural and synthetic calcium phosphate for biomedical use. We report the determination of the values obtained for the diffusivity (a), effusivity (ε), thermal conductivity (k) and heat capacity (ρc), of 6 synthetic calcium phosphate samples and 5 natural calcium phosphate samples. The values obtained for the thermal properties of synthetic calcium phosphates turn out to be 82% similar to the values obtained for calcium phosphates of natural origin. This behavior allows us to obtained calcium phosphates in our laboratory like osseous substitutes with thermal properties similar to the calcium phosphates of natural origin.
1287(2010); http://dx.doi.org/10.1063/1.3507421View Description Hide Description
There is presently an intense discussion if extremely low frequency electromagnetic field (ELF‐EMF) exposure has consequences for human health. This include exposure to structures and appliances from this range of frequency in the electromagnetic (EM) spectrum. Biological effects of such exposures have been noted frequently, although the implications for specific health effects is not that clear. The basic interactions mechanisms between such fields and living matter is unknown. Numerous hypotheses have been suggested, although none is convincingly supported by experimental data. Various cellular components, processes, and systems can be affected by EMF exposure. Since it is unlikely that EMF can induce DNA damage directly, most studies have examined EMF effects on the cell membrane level, general and specific gene expression, and signal transduction pathways. Even more, a large number of studies have been performed regarding cell proliferation, cell cycle regulation, cell differentiation, metabolism, and various physiological characteristics of cells. The aim of this letter is present the hypothesis of a possible quantum mechanic effect generated by the exposure of ELF EMF, an event which is compatible with the multitude of effects observed after exposure. Based on an extensive literature review, we suggest that ELF EMF exposure is able to perform such activation restructuring the electronic level of occupancy of free radicals in molecules interacting with DNA structures.