Quantum gases in optical lattices

The experimental realization of correlated quantum phases with ultracold gases in optical lattices and their theoretical understanding has witnessed remarkable progress during the last decade. In this review we introduce basic concepts and tools to describe the many-body physics of quantum gases in optical lattices. This includes the derivation of effective lattice Hamiltonians from first principles and an overview of the emerging quantum phases. Additionally, state-of-the-art numerical tools to quantitatively treat bosons or fermions on different lattices are introduced.Comment: 29 pages, 3 figures. This article will be published as Chapter 2 in "Quantum gas experiments - exploring many-body states", edited by P. Torma and K. Sengstock, Imperial College Press, London, to be published 201

Finite temperature dynamical correlations for the dimerized spin-1/2 chain

We use the density matrix renormalization group method (DMRG) to compute the frequency and momentum resolved spin-spin correlation functions of a dimerized spin-1/2 chain under a magnetic field at finite temperature. The spectral features strongly depend on the regime of the magnetic field. For increasing magnetic fields, the transitions from a gapped spin liquid phase to a Tomonaga-Luttinger liquid, and then to a totally polarized phase, can be identified in the spectra. Compared to the zero temperature case, the finite temperature excitations give rise to additional spectral features that we compute numerically and identify analytically as transitions from thermally excited states. We compute quantitatively the broadening of the dispersion of a single spin-flip excitation due to the temperature and find a strong asymmetric broadening. We discuss the consequences of these findings for neutron experiments on dimerized one dimensional quantum chains.Comment: 13 pages, 14 figure

Big experimenter is watching you! Anonymity and prosocial behavior in the laboratory

Social preference research has received considerable attention in recent years. Researchers have demonstrated that the presence of people with other-regarding preferences can have important implications in many economic dimensions. However, it is important to be aware of the fact that the empirical basis of this literature relies to a large extent on experiments that do not provide anonymity between experimenter and subject. It has been argued that this lack of experimenter-subject anonymity may create selsh incentives to engage in seemingly other-regarding behavior. If this were the case these experiments would overestimate the importance of social preferences. Previous studies provide mixed results and methodological dierences within and across studies make it difcult to isolate the impact of experimenter-subject anonymity on prosocial behavior. In this paper we use a novel procedure that allows us to examine the impact of the exact same ceteris-paribus variation in anonymity on behavior in three of the most commonly used games in the social preference literature. Our data reveals that introducing experimenter-subject anonymity has only minor, insignicant, eects on prosocial behavior.Scrutiny, anonymity, laboratory experiments, prosocial behavior

Big Experimenter Is Watching You! Anonymity and Prosocial Behavior in the Laboratory

Social preference research has received considerable attention in recent years. Researchers have demonstrated that the presence of people with social preferences has important implications in many economic domains. However, it is important to be aware of the fact that the empirical basis of this literature relies to a large extent on experiments that do not provide anonymity between experimenter and subject. It has been argued that this lack of experimenter-subject anonymity may create selfish incentives to engage in seemingly other-regarding behavior. If this were the case these experiments would overestimate the importance of social preferences. Previous studies provide mixed results and methodological differences within and across studies make it difficult to isolate the impact of experimenter-subject anonymity on prosocial behavior. In this paper we use a novel procedure that allows us to examine the impact of the exact same ceteris-paribus variation in anonymity on behavior in three of the most commonly used games in the social preference literature. Our data does not support the hypothesis that introducing experimenter-subject anonymity affects observed prosocial behavior. We do not observe significant effects of experimenter-subject anonymity on prosocial behavior in any of our games.scrutiny, prosocial behavior, anonymity, laboratory experiments

People v. Hicks: Sentencing Laws and Sex Offenses - A Disingenuous Approach by the California Supreme Court

This Casenote questions the holding in People v. Hicks, a California Supreme Court decision in December 1993, which held that sex offenders are subject to multiple full-term consecutive sentences for both non-sex and sex offenses. The author argues that this decision exceeds the interpretive limits of the sex offender sentencing statutes in California. Based on a potentially applicable statutory prohibition regarding multiple punishments, this holding is criticized for abusing the court\u27s interpretive authority. In addition, this decision is argued to open the door to a potential dramatic increase in sentences that the legislature never intended

Private Enterprise for Public Health: Opportunities for Business to Improve Women's and Children's Health

This guide, developed by FSG and published by the Innovation Working Group in support of the global Every Woman, Every Child effort, explores how companies can create shared value in women's and children's health. The document sets out opportunities for multiple different industries to develop new product and services, improve delivery systems and strengthen health systems that can support global efforts to save 16 million women's and children's lives between now and 2015. It particularly notes that companies need not wait for health services to "catch up" with their economic model, but rather they can work proactively to help accelerate change, by partnering with other industries, civil society and the public sector to create collective impact in a specific location. The aim of the guide is to catalyze these transformative partnerships

Relaxation of antiferromagnetic order in spin-1/2 chains following a quantum quench

We study the unitary time evolution of antiferromagnetic order in anisotropic Heisenberg chains that are initially prepared in a pure quantum state far from equilibrium. Our analysis indicates that the antiferromagnetic order imprinted in the initial state vanishes exponentially. Depending on the anisotropy parameter, oscillatory or non-oscillatory relaxation dynamics is observed. Furthermore, the corresponding relaxation time exhibits a at the critical point, in contrast to the usual notion of critical slowing down, from which a maximum is expected.Comment: 4 pages, 4 figure

Shaping Global Partnerships for a Post-2015 World

As we discuss the post-2015 development agenda, how can we empower global partnerships to achieve the transformational change we need for a better future? This article provides lessons and best practices from six diverse initiatives on applying the collective impact approach on a global scale -- how to develop a common agenda, operate effective shared measurement systems, support and coordinate activities, facilitate communication, and provide strong governance for global collaborative efforts.The report uses a collective impact lens to research and evaluate a range of global partnerships, with a particular emphasis on these six diverse initiatives: Roll Back Malaria Partnership, Global Alliance for Improved Nutrition, Global Road Safety Partnership, the World Economic Forum's New Vision for Agriculture, the Global Partnership for Education, and the World Wide Fund for Nature