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It has been recently claimed that cosmologies with time dependent speed of light might solve some of the problems of the standard cosmological scenario, as well as inflationary scenarios. In this letter we show that most...

We fit the BOOMERANG, MAXIMA and COBE/DMR measurements of the cosmic microwave background anisotropy in spatially flat cosmological models where departures from standard recombination of the primeval plasma are parametri...

We consider astronomical and local bounds on the time variation of fundamental constants to test some generic Kaluza-Klein–like models and some particular cases of Beckenstein theory. Bounds on the free parameters of t...

Electrostatics of conductors Static magnetic field Superconductivity The propagation of electromagnetic waves Spatial dispersion Diffraction of X rays in crystals.

A new method for automatic indexing and retrieval is described. The approach is to take advantage of implicit higher-order structure in the association of terms with documents (“semantic structure”) in order to impro...

Materias / palabras clave: Graphene; Condensed matter physics; Quantum Hall effect; Physics; Electron; Landau quantization; Quantum point contact; Materials science; Quantum well; Quantum mechanics; Laser

Previous article Next article An Algorithm for Least-Squares Estimation of Nonlinear ParametersDonald W. MarquardtDonald W. Marquardthttps://doi.org/10.1137/0111030PDFPDF PLUSBibTexSections ToolsAdd to favoritesExport Ci...

We propose to generalize Bekenstein model for the time variation of the fine structure "constant" αem to QCD strong coupling constant αS. We find that, except for a “fine tuned” choice of the free parameters, the e...

We discuss observational constraints coming from CMB and type Ia supernovae, for the model of accelerated universe produced by gravitational leakage into extra dimensions. Our fits indicate that the model is currently in...