Cosmic Lensing -- A new paradigm for Universe expansion interpretation

The Einstein's General Relativity theory and the Friedmann-Lemaitre-Robertson-Walker (FLRW) metrics define the main equations that rule the history and future of the Universe. The Standard Model for cosmology collects this knowledge along with some other elements as cosmological distances. Thus, the link between the theory and observations is performed through some basic cosmological distances as luminosity distance $D_L$ and angular diameter distance $D_A$. In this paper, Cosmic Lensing (CL) is presented. CL is a novel paradigm that demonstrates the inverse square law invariance within the FLRW geometry. In this way, CL reveals a new relationship between $D_L$ and $D_A$ in an expanding universe given by $D_L=D_A(1+z)$, opposed to the relation $D_L=D_A(1+z)^2$ established about a century ago and assumed by the Standard Model. In the same sense, a compatible surface brightness vs luminosity relation -- different from the one proposed by Tolman -- is derived from Cosmic Microwave Background (CMB) equations. As a consequence, previous cosmology methods and results entrusting on luminosity as observational data must be reviewed. The expansion rate and the relative densities of the dark components of the Universe, as dark matter and dark energy, should be revised within the new paradigm

Separability criteria based on the Bloch representation of density matrices

We study the separability of bipartite quantum systems in arbitrary dimensions using the Bloch representation of their density matrix. This approach enables us to find an alternative characterization of the separability problem, from which we derive a necessary condition and sufficient conditions for separability. For a certain class of states the necessary condition and a sufficient condition turn out to be equivalent, therefore yielding a necessary and sufficient condition. The proofs of the sufficient conditions are constructive, thus providing decompositions in pure product states for the states that satisfy them. We provide examples that show the ability of these conditions to detect entanglement. In particular, the necessary condition is proved to be strong enough to detect bound entangled states.Comment: 17 pages, no figures; Section 4.2 improved; final version: minor changes, added references, to appear in QI

Ultrasonographic identification of the dorsal atlantoaxial ligament in dogs

Objective: To determine the ability to identify the dorsal atlantoaxial ligament during ultrasonographic examination of dogs. Study design: Canine cadaveric study. Sample population: Canine cervical spines (n = 35). Methods: Thirty-five canine cadavers with an estimated body weight of 6-35 kg were retrieved. Five cervical spines were dissected to assess the length and thickness of the dorsal atlantoaxial ligament and correlate ultrasound-guided injection of ink with anatomical dissection. Ultrasonographic evaluation of the dorsal atlantoaxial ligament was performed on 30 cadavers. The visibility of the dorsal atlantoaxial ligament in both the transverse and the sagittal planes was subjectively scored (0-3). Results: The dorsal atlantoaxial ligament was detectable on ultrasonographic examination in all cadavers: 27/30 and 28/30 were graded as moderately visible (grade 2) or clearly visible (grade 3) in the sagittal and transverse view, respectively. Only 1/30 cadaver specimen of a large breed dog was graded as 1 (indistinct) in both the sagittal and transverse planes. None of the cadavers were graded as 0 (not visible) in any view. Conclusion: The dorsal atlantoaxial ligament can be identified in ultrasonographic examination of normal canine cadavers. Future studies on animals with clinical atlantoaxial instability/subluxation are needed to evaluate the role of this imaging technique in providing a safer diagnosis of this condition. Clinical relevance: Ultrasonographic examination of the dorsal atlantoaxial ligament could potentially provide a noninvasive and safe imaging technique that may contribute to the diagnosis of atlantoaxial instability/subluxation in dogs

Guide to the classics: Don Quixote, the world’s first novel – and one of the best

Completed by Cervantes when he was in prison, Don Quixote is the tale of a man so passionate about reading he leaves home to live the life of his fictional heroes

Extragalactic line surveys

40 years have passed since the first molecular detection outside our Galaxy. Since then, our knowledge on the distribution, kinematics and composition of the molecular material in the extragalactic ISM has built up significantly based not only on the carbon monoxide observations but also in the more than 50 molecular species detected. In particular, line surveys have been proven to be excellent tools to study the chemical composition in the nuclei of galaxies. Such studies have been favored by the increasing instantaneous bandwidth of current mm and sub-mm facilities. Here I will summarize the highlights of extragalactic molecular spectroscopy, mostly focusing in the results from molecular line surveys published in the last few years as well as the aims of still ongoing projects.Comment: 9 pages, 2 figures, in Proceedings of the 280th Symposium of the International Astronomical Unio