Real time demonstration of high bitrate quantum random number generation with coherent laser light

We present a random number generation scheme that uses broadband measurements of the vacuum field contained in the radio-frequency sidebands of a single-mode laser. Even though the measurements may contain technical noise, we show that suitable algorithms can transform the digitized photocurrents into a string of random numbers that can be made arbitrarily correlated with a subset of the quantum fluctuations (high quantum correlation regime) or arbitrarily immune to environmental fluctuations (high environmental immunity). We demonstrate up to 2 Gbps of real time random number generation that were verified using standard randomness tests

Fermion bag solutions to some sign problems in four-fermion field theories

Lattice four-fermion models containing $N$ flavors of staggered fermions, that are invariant under $Z_2$ and U(1) chiral symmetries, are known to suffer from sign problems when formulated using the auxiliary field approach. Although these problems have been ignored in previous studies, they can be severe. Here we show that the sign problems disappear when the models are formulated in the fermion bag approach, allowing us to solve them rigorously for the first time.Comment: references adde

Modelamento de dados para o balanço hídrico.

O balanço hídrico é um método muito eficaz e de relevante importância para a determinação e conhecimento de um tipo de clima em sua região, prevendo assim, as condições mais favoráveis para o plantio no meio agrícola e evitando futuros prejuízos em decorrência de uma má manutenção hídrica por meio das chuvas (MARIN et al., 2008). Diversas variáveis utilizadas influem direta ou indiretamente, podendo ser citados a precipitação (P), evapotranspiração potencial (ETP), temperatura média (Tméd), deficiência hídrica (DEF) e excedente hídrico (EXC) (SENTELHAS et al., 2000). O conhecimento prévio da capacidade que o solo tem de armazenamento de água (CAD) possui uma grande importância nas determinações do balanço hídrico, juntamente com dados adquiridos por meio das estações meteorológicas. O objetivo principal é a retirada de dados de planilhas gerando assim mapas com as características necessárias para uma interpretação gráfica simples e de fácil entendimento

How accurate are pedotransfer functions for bulk density for Brazilian soils?

The aim of this study was to evaluate the predictive capability of PTFs available in the literature to estimate soil pb in different regions of Brazil, using different metrics (mean absolute error (MAE), root mean squared error (RMSE), mean error (ME) and regression error characteristic (REC) curve)

Impact assessment study of climate change on agricultural zoning.

The present paper assesses the specific impacts of potential climate change, as indicated by IPCC scenarios in 2001, in the agricultural zoning of coffee and corn, applying the methodology used by the Brazilian Department of Agriculture