17 research outputs found

    1/f1/f noise in variable range hopping conduction

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    A mechanism of 1/f1/f noise due to traps formed by impurities which have no neighbors with close energies in their vicinity is studied. Such traps slowly exchange electrons with the rest of conducting media. The concentration of traps and proportional to it 1/f1/f noise exponentially grow with decreasing temperature in the variable range hopping regime. This theory provides smooth transition to the nearest neighbor hopping case where it predicts a very weak temperature dependence

    Implications of Space-Time foam for Entanglement Correlations of Neutral Kaons

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    The role of CPTCPT invariance and consequences for bipartite entanglement of neutral (K) mesons are discussed. A relaxation of CPTCPT leads to a modification of the entanglement which is known as the ω\omega effect. The relaxation of assumptions required to prove the CPTCPT theorem are examined within the context of models of space-time foam. It is shown that the evasion of the EPR type entanglement implied by CPTCPT (which is connected with spin statistics) is rather elusive. Relaxation of locality (through non-commutative geometry) or the introduction of decoherence by themselves do not lead to a destruction of the entanglement. So far we find only one model which is based on non-critical strings and D-particle capture and recoil that leads to a stochastic contribution to the space-time metric and consequent change in the neutral meson bipartite entanglement. The lack of an omega effect is demonstrated for a class of models based on thermal like baths which are generally considered as generic models of decoherence

    Drought Monitoring and Assessment: Status and Trends in the United States

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    Drought is a normal, recurring feature of climate. The characteristics of this hazard, along with its far-reaching impacts, make its effects on society, economy, and environment difficult to identify and quantify. A national drought watch system has been recommended as a necessary component of drought assessment and management. The National Drought Mitigation Center, in collaboration with others, has undertaken a number of drought watch activities for the past few years, using a variety of resources available over the Internet. These resources include tools such as the Standardized Precipitation Index, a new drought index that is more reliable for detecting emerging drought conditions
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