Entanglement detection in hybrid optomechanical systems

We study a device formed by a Bose Einstein condensate (BEC) coupled to the field of a cavity with a moving end-mirror and find a working point such that the mirror-light entanglement is reproduced by the BEC-light quantum correlations. This provides an experimentally viable tool for inferring mirror-light entanglement with only a limited set of assumptions. We prove the existence of tripartite entanglement in the hybrid device, persisting up to temperatures of a few milli-Kelvin, and discuss a scheme to detect it.Comment: 6 pages, 7 figures, published versio

Scale symmetry in classical and quantum mechanics

In this paper we address again the issue of the scale anomaly in quantum mechanical models with inverse square potential. In particular we examine the interplay between the classical and quantum aspects of the system using in both cases an operatorial approach.Comment: 11 pages, Late

On Gravitational Waves in Spacetimes with a Nonvanishing Cosmological Constant

We study the effect of a cosmological constant $\Lambda$ on the propagation and detection of gravitational waves. To this purpose we investigate the linearised Einstein's equations with terms up to linear order in $\Lambda$ in a de Sitter and an anti-de Sitter background spacetime. In this framework the cosmological term does not induce changes in the polarization states of the waves, whereas the amplitude gets modified with terms depending on $\Lambda$. Moreover, if a source emits a periodic waveform, its periodicity as measured by a distant observer gets modified. These effects are, however, extremely tiny and thus well below the detectability by some twenty orders of magnitude within present gravitational wave detectors such as LIGO or future planned ones such as LISA.Comment: 8 pages, 4 figures, accepted for publication in Physical Review

Blog sobre legislação ambiental brasileira na Embrapa: a informação ao alcance de todos.

A legislação ambiental brasileira visa fiscalizar e punir aquele que causa dano ao meio ambiente, bem como garantir qualidade de vida e sustentabilidade ambiental para todos. Através de meios eletrônicos é possível obter informações da legislação brasileira. A disponibilidade em meios eletrônicos, especialmente internet, facilita o acesso da população às leis, levando a todos a conscientização das legislações existentes no Brasil. O objetivo desta pesquisa é reunir, classificar e disponibilizar a legislação ambiental, de forma fácil e clara, ao alcance e acesso a toda população. O acesso pode ser feito através de um link que será disponibilizado no site da Embrapa Gado de Corte. Ao acessar a página, o visitante visualiza a legislação ambiental que foi dividida por assuntos. Disponibiliza-se também a sinopse da lei, o número da legislação e o texto da legislação na íntegra através de hiperlink. Este é interligado e direcionado a um site do governo federal, que atualiza regularmente todas as legislações. No site da Embrapa será disponibilizado o acesso de diversas normas jurídicas e administrativas, de âmbito ambiental para pesquisas e download. Hoje temos, relacionado com a legislação ambiental, registros de 37 Leis, 18 Decretos, dois Decreto-Lei, 10 Portarias Normativas do IBAMA, 33 Resoluções do Conama, uma Portaria IPHAN, uma Instrução Normativa MMA, duas Portarias do Ibama, uma Portaria do Ministério da Saúde, uma Resolução RDC e a Constituição da República Federativa do Brasil de 1988. As normas jurídicas ambientais têm como objetivo disciplinar atividades humanas, para torná-las compatível com a proteção do meio ambiente. A pesquisa procura conscientizar a existência das leis ambientais, facilitando e disponibilizando seu acesso pela internet na página da Embrapa. A educação e informações direcionadas e especializadas, como a proposta desta pesquisa, pode auxiliar na transformação do ambiente em que vivemos, além de contribuir na pesquisa educacional dos interessados

Idleness-aware dynamic power mode selection on the i.Mx 7ULP iot edge processor

Power management is a crucial concern in micro-controller platforms for the Internet of Things (IoT) edge. Many applications present a variable and difficult to predict workload profile, usually driven by external inputs. The dynamic tuning of power consumption to the application requirements is indeed a viable approach to save energy. In this paper, we propose the implementation of a power management strategy for a novel low-cost low-power heterogeneous dual-core SoC for IoT edge fabricated in 28 nm FD-SOI technology. Ss with more complex power management policies implemented on high-end application processors, we propose a power management strategy where the power mode is dynamically selected to ensure user-specified target idleness. We demonstrate that the dynamic power mode selection introduced by our power manager allows achieving more than 43% power consumption reduction with respect to static worst-case power mode selection, without any significant penalty in the performance of a running application

Geometric Dequantization

Dequantization is a set of rules which turn quantum mechanics (QM) into classical mechanics (CM). It is not the WKB limit of QM. In this paper we show that, by extending time to a 3-dimensional "supertime", we can dequantize the system in the sense of turning the Feynman path integral version of QM into the functional counterpart of the Koopman-von Neumann operatorial approach to CM. Somehow this procedure is the inverse of geometric quantization and we present it in three different polarizations: the Schroedinger, the momentum and the coherent states ones.Comment: 50+1 pages, Late

Plasma antioxidants from chocolate

There is some speculation that dietary flavonoids from chocolate, in particular (-)epicatechin, may promote cardiovascular health as a result of direct antioxidant effects or through antithrombotic mechanisms. Here we show that consumption of plain, dark chocolate results in an increase in both the total antioxidant capacity and the (-)epicatechin content of blood plasma, but that these effects are markedly reduced when the chocolate is consumed with milk or if milk is incorporated as milk chocolate. Our findings indicate that milk may interfere with the absorption of antioxidants from chocolate in vivo and may therefore negate the potential health benefits that can be derived from eating moderate amounts of dark chocolate

Spontaneous Breakdown of Superhydrophobicity

In some cases water droplets can completely wet micro-structured superhydrophobic surfaces. The {\it dynamics} of this rapid process is analyzed by ultra-high-speed imaging. Depending on the scales of the micro-structure, the wetting fronts propagate smoothly and circularly or -- more interestingly -- in a {\it stepwise} manner, leading to a growing {\it square-shaped} wetted area: entering a new row perpendicular to the direction of front propagation takes milliseconds, whereas once this has happened, the row itself fills in microseconds ({\it ``zipping''})Comment: Accepted for publication in Physical Review Letter

Macroscopic fluctuations theory of aerogel dynamics

We consider the thermodynamic potential describing the macroscopic fluctuation of the current and local energy of a general class of Hamiltonian models including aerogels. We argue that this potential is neither analytic nor strictly convex, a property that should be expected in general but missing from models studied in the literature. This opens the possibility of describing in terms of a thermodynamic potential non-equilibrium phase transitions in a concrete physical context. This special behaviour of the thermodynamic potential is caused by the fact that the energy current is carried by particles which may have arbitrary low speed with sufficiently large probability.Comment: final versio