Advantages of Unfair Quantum Ground-State Sampling

The debate around the potential superiority of quantum annealers over their classical counterparts has been ongoing since the inception of the field by Kadowaki and Nishimori close to two decades ago. Recent technological breakthroughs in the field, which have led to the manufacture of experimental prototypes of quantum annealing optimizers with sizes approaching the practical regime, have reignited this discussion. However, the demonstration of quantum annealing speedups remains to this day an elusive albeit coveted goal. Here, we examine the power of quantum annealers to provide a different type of quantum enhancement of practical relevance, namely, their ability to serve as useful samplers from the ground-state manifolds of combinatorial optimization problems. We study, both numerically by simulating ideal stoquastic and non-stoquastic quantum annealing processes, and experimentally, using a commercially available quantum annealing processor, the ability of quantum annealers to sample the ground-states of spin glasses differently than classical thermal samplers. We demonstrate that i) quantum annealers in general sample the ground-state manifolds of spin glasses very differently than thermal optimizers, ii) the nature of the quantum fluctuations driving the annealing process has a decisive effect on the final distribution over ground-states, and iii) the experimental quantum annealer samples ground-state manifolds significantly differently than thermal and ideal quantum annealers. We illustrate how quantum annealers may serve as powerful tools when complementing standard sampling algorithms.Comment: 13 pages, 11 figure

History of Geology up to 1780

Ancient civilisations in contact with nature inquired about their origins and about particular geodynamic phenomena. In most cases they satisfied themselves with empiric explanations; they even used deities in order to understand inexplicable situations. Little by little humans learnt how to observe their environment and arrange processes. During the Renaissance the first geologic principIes were born and this knowledge spread rapidly. Natural phenomena were understood in terms of dynamic cause-effect, although many dogmatic and magic interpretations persisted. Many authors agree that geology, began to be structured as a science in the second half of the eighteenth century with Abraham Gottlob Werner (17491817), father of Neptunism (Figure 1). However, sorne geologic paradigms such as diluvialism existed before neptunism; all of them contained countless mistakes and ambiguities. This article outlines the period up until 1780, which thus incorporates the work of James Hutton (see Famous Geologists: Hutton). His ideas were important in the development of geology, more specifically relating to the origins and dating of rocks. Geology was not completely defined till the birth of Stratigraphy at the end of the eighteenth century and Palaeontology at around 1830

Distributed and Interactive Simulations Operating at Large Scale for Transcontinental Experimentation

This paper addresses the use of emerging technologies to respond to the increasing needs for larger and more sophisticated agent-based simulations of urban areas. The U.S. Joint Forces Command has found it useful to seek out and apply technologies largely developed for academic research in the physical sciences. The use of these techniques in transcontinentally distributed, interactive experimentation has been shown to be effective and stable and the analyses of the data find parallels in the behavioral sciences. The authors relate their decade and a half experience in implementing high performance computing hardware, software and user inter-face architectures. These have enabled heretofore unachievable results. They focus on three advances: the use of general purpose graphics processing units as computing accelerators, the efficiencies derived from implementing interest managed routers in distributed systems, and the benefits of effective data management for the voluminous information

Forschungsdaten und Bibliometrie: Neue Services für die Wissenschaft

Die gezielte Unterstützung universitärer Forschung ist für Universitätsbibliotheken keine neue Herausforderung, denn die bedarfsgerechte Erwerbung und Erschließung relevanter Fachinformationen sowie die Gewährleistung des Zugangs zu den benötigten Medien sind ihre zentralen Aufgaben. Neu an dieser Herausforderung sind die schier unerschöpflichen Möglichkeiten der Informationsversorgung, die aus der digitalen Medienrevolution und der rasanten Entwicklung der Informationstechnologie erwachsen. Die Wissenschaftler/-innen erwarten einen umfassenden, schnellen, komfortablen und jederzeit störungsfreien Zugang zu den Informationsquellen. Der direkte Weg vom bibliographischen Nachweis aus Katalogen und Datenbanken zum elektronisch verfügbaren Volltext wird – mindestens bei den MINT-Fächern (Mathematik, Informatik, Naturwissenschaften, Technik) – mittlerweile als Standard angesehen. Bibliothekarische Angebote wie Schulungen zur Förderung der Informations- und Medienkompetenz, Literaturverwaltung, Publikationsserver haben das bibliothekarische Portfolio in den letzten Jahren erweitert und zählen inzwischen zum bibliothekarischen Alltagsgeschäft

Police Chemistry

Johann von Justi, the foremost literary cameralist of his generation, served as chief police commissioner in Göttingen between 1755 and 1757. While in Göttingen, Justi offered lectures at the university on the “economic, police and cameral sciences.” He also arrested vagrants, wrote on chemistry, disciplined unruly students, conducted chemical experiments, supervised the pricing of Göttingen\u27s staple goods, engaged in a public controversy with a prominent Berlin chemist, edited and published a bi-weekly periodical (Göttingische Policey-Amts Nachrichien), and worked with the university\u27s curator to refashion the academic structure of the sciences. Taken together, these various activities reflected his broad vision for social and academic change, a vision with important implications for the form and content of the sciences. Drawing on archival material in Göttingen, on articles from the Policey-Amts Nachrichten, and on Justi\u27s other cameralist and chemical writings, I use his everyday experiences as a local police official to explore the meaning of his chemical work. I argue that Justi\u27s chemistry was suffused with the cameralist dreams and ambitions of a small-town police commissioner. It is what I call police chemistry

Cognitive and emotional effects of Deep Brain Stimulation of the Subthalamic Nucleus in patients with Parkinson's disease

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become an effective and secure option for treatment of Parkinson´s disease (PD). Its effect on improving motor impairments following dopaminergic depletion in the substantia nigra has been variously shown. The influence of STN-DBS on concomitant non-motor symptoms has also reached more and more of attention, since these may have the potential to affect subjectively perceived quality of life in patients. Behavioral, affective and cognitive changes in patients after STN-DBS have thus been considerably studied in recent years. The present thesis aimed to investigate STN-DBS modulations on different cognitive and emotional functions in PD patients. The STN is supposed to hold a crucial role in action selection and reward processing as well as in perceptual decision-making. The first thesis project investigated whether stimulation of the STN influences the patients´ selective ability to act for anticipated reward or loss, or whether DBS changes action selection independent from motivational valence. Behavioral results demonstrate the impact of STN-DBS on motivational action control in PD by selectively improving action execution when rewards are anticipated. Thus, STN-DBS establishes a reliable congruency between action and reward anticipation. The second project investigated whether STN-DBS in PD patients influences decision-making under difficult, high-risk decisions. Results show that stimulation of the STN affected perceptual decision-making depending on the difficulty of decisions and as a function of baseline impulsivity in patients. DBS of the STN selectively affected the tendency to stick with a default option on difficult decisions and increased accuracy of responses. Finally, I conducted an experimental setting to assess STN-DBS impact on implicit and explicit processing of emotional semantic and facial stimuli in an affective priming paradigm. I found that even reduced facial information is sufficient to induce automatic implicit emotional processing and can lead to classical and inverse priming effects in healthy control participants, but also in non-stimulated PD patients. In these patients, specific altered processing of the emotions happiness and disgust was detected. The experimental setting was finally applied in stimulation-treated PD patients. STN-DBS affected explicit more than implicit processing, indicating basal ganglia-thalamocortical regulations on explicit, and only attenuated on implicit emotion processing. Profound diminishing effects on response accuracy for disgust-connoted stimulus material, but also an ameliorating effect on fear stimuli could be demonstrated under stimulation. Taken together, this PhD thesis demonstrates that STN-DBS improved action selection under reward anticipation, facilitated decision-making under difficult decisions, and finally, influenced particularly explicit, but also implicit emotional processing. The results provide causal evidence for the potential of STN-DBS to influence cognitive and emotional aspects in patients and to have considerable impacts on quality of life besides improved motor functioning