12,401 research outputs found
Statistics of work and fluctuation theorems for microcanonical initial states
The work performed on a system in a microcanonical state by changes in a
control parameter is characterized in terms of its statistics. The transition
probabilities between eigenstates of the system Hamiltonians at the beginning
and the end of the parameter change obey a detailed balance-like relation from
which various forms of the microcanonical fluctuation theorem are obtained. As
an example, sudden deformations of a two dimensional harmonic oscillator
potential are considered and the validity of the microcanonical Jarzynski
equality connecting the degrees of degeneracy of energy eigenvalues before and
after the control parameter change is confirmed.Comment: 16 pages, 5 figure
Revealing correlations between a system and an inaccessible environment
How can we detect that our local, controllable quantum system is correlated
with some other inaccessible environmental system? The local detection method
developed in recent years allows to realize a dynamical witness for
correlations without requiring knowledge of or access to the environment that
is correlated with the local accessible quantum system. Here, we provide a
brief summary of the theoretical method and recent experimental studies with
single photons and trapped ions coupled to increasingly complex environments.Comment: 12 pages, 3 figure
Nonsustainable Use of Renewable Resources: Mangrove Deforestation and Mariculture in Ecuador
The paper provides a conceptual model that examines (i) open-access exploitation and(ii) mangrove deforestation as two potential causes for the scarcity of post-larval shrimp inputs to shrimp mariculture in Ecuador. Results indicate that conversion of mangrove ecosystems to shrimp ponds may have obtained short-term profit at the expense of long-term productivity. Open-access collection of post-larval shrimp may also have contributed to dwindling stock levels. Specific policy recommendations are presented, and future empirical studies are proposed.Mariculture, mangroves, deforestation, shrimp, fisheries, Ecuador, Environmental Economics and Policy, Production Economics,
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