Fast optimization algorithms and the cosmological constant

Denef and Douglas have observed that in certain landscape models the problem of finding small values of the cosmological constant is a large instance of an NP-hard problem. The number of elementary operations (quantum gates) needed to solve this problem by brute force search exceeds the estimated computational capacity of the observable universe. Here we describe a way out of this puzzling circumstance: despite being NP-hard, the problem of finding a small cosmological constant can be attacked by more sophisticated algorithms whose performance vastly exceeds brute force search. In fact, in some parameter regimes the average-case complexity is polynomial. We demonstrate this by explicitly finding a cosmological constant of order $10^{-120}$ in a randomly generated $10^9$-dimensional ADK landscape.Comment: 19 pages, 5 figure

The global nuclear liability regime post Fukushima Daiichi

Nuclear liability regimes are important as they ensure that potential victims will be compensated promptly and efficiently after a nuclear accident. The accident at Fukushima Daiichi in Japan in 2011 prompted a review of the global nuclear liability regime that remains on-going. Progress has been slow, but over the next few years the European Union is set to announce its new proposals. Meanwhile, in 2015, another global nuclear liability regime, the Convention on Supplementary Compensation for Nuclear Damage, has entered into force. This paper aims to move the debate in the literature on nuclear liability and focuses on the four following major issues: (1) reviews third-party nuclear liability regimes currently in operation around the world; (2) analyses the international nuclear liability regime following the accident at Fukushima Daiichi; (3) comparatively assesses the liability regimes for nuclear energy and the non-nuclear energy sector; and (4) presents the future outlook for possible developments in the global nuclear liability regime

An Assessment Of A Wildlife Habitat Evaluation Methodology For Alaska

Thesis (M.S.) University of Alaska Fairbanks, 198

The Silver Anniversary of the United States’ Exclusive Economic Zone: Twenty-Five Years of Ocean Use and Abuse, and the Possibility of a Blue Water Public Trust Doctrine

Sustainably managing marine ecosystems has proved nearly impossible, with few success stories. Ecosystem management failures largely stem from the traditional sector-by-sector, issue-by-issue approach to managing ocean-borne activities—an approach that is fundamentally unable to keep pace with the dynamics of coupled human, ecologi cal and oceanographic systems. In the United States today there are over twenty federal agencies and thirty-five coastal states and territories operating under dozens of statutory authorities shaping coastal and ocean policy. Among marine ecologists and policy experts there is an emerging consensus that a major overhaul in U.S. ocean governance is necessary. This Article suggests that the public trust doctrine—an ancient legal concept that is already incorporated in U.S. state coastal laws—can uniquely provide a unifying concept for U.S. federal ocean governance. Though the public trust concept can be located in the legal systems of many countries, it robustly manifests in the United States, where it has historically protected the public’s rights to fishing, navigation, and commerce in and over navigable waterways and tidal waters. In its most basic form, the doctrine obliges governments to manage common natural resources, the body of the trust, in the best interest of their citizens, the beneficiaries of the trust. Today the public trust doctrin e is integral to the protection of coastal ecosystems and beach access in many states and has even made its way into state constitutions. It would be simple, and seemingly logical, to assume that the same fiduciary responsibility of states to protect public trust uses of their waters extends to all marine resources within the United States’ 200-mile Exclusive Economic Zone (EEZ). However an artificial line has been drawn around state waters, and the legal authority and responsibility of the U.S. government to protect public trust resources in the vast space of its EEZ (the largest of any country on earth) have never been fully and expressly established. Securing the place of the public trust doctrine in U.S. federal oceans management would be valuable, given the immense pressure to exploit EEZ resources, the failure of the current regulatory approach, improved scientific understanding of the interconnected nature of ocean ecosystems, and the growing demand for sustainable management of ocean resources. This Article will outline the development of states’ public trust doctrines; discuss the expansion of U.S. sovereignty over its neighboring ocean waters during the twentieth century; analyze possible avenues for expanding the doctrine to federal waters; and consider how a federal public trust doctrine could clarify some specific emerging issues in U.S. oceans management. At the heart of our analysis lie three questions: (1) does a federal public trust doctrine exist; (2) if so, can we rightfully extend it to include the entirety of the U.S. ocean waters; and (3) could the doctrine provide the missing catalyst for federal agencies to manage the use of U.S. ocean resources in a coordinated, sustainable fashion

Asymptotics for the critical level and a strong invariance principle for high intensity shot noise fields

We study fine properties of the convergence of a high intensity shot noise field towards the Gaussian field with the same covariance structure. In particular we (i) establish a strong invariance principle, i.e. a quantitative coupling between a high intensity shot noise field and the Gaussian limit such that they are uniformly close on large domains with high probability, and (ii) use this to derive an asymptotic expansion for the critical level above which the excursion sets of the shot noise field percolate.Comment: 24 pages, 2 figures. Version accepted for publication in AIH

Compensating for severe nuclear accidents: An expert elucidation

We present the results of a structured discussion held in London in July 2014 involving a panel of experts drawn from three communities: specialists on aspects of risk and insurance; lawyers concerned with issues of nuclear law; and safety and environmental regulators. The discussions were held on the basis of participant anonymity. The process emphasised three considerations: conceptions of loss arising from a severe nuclear accident; the specifics of the Fukushima-Daiichi accident and what it means for policy and strategy going forward; and the future of liability regimes. We observe some stoicism from those closest to implementation of policies and procedures associated with nuclear risks, but a lower level of certainty and confidence among those concerned with nuclear energy regulation