Quantum tomography for collider physics: Illustrations with lepton pair production

Quantum tomography is a method to experimentally extract all that is observable about a quantum mechanical system. We introduce quantum tomography to collider physics with the illustration of the angular distribution of lepton pairs. The tomographic method bypasses much of the field-theoretic formalism to concentrate on what can be observed with experimental data, and how to characterize the data. We provide a practical, experimentally-driven guide to model-independent analysis using density matrices at every step. Comparison with traditional methods of analyzing angular correlations of inclusive reactions finds many advantages in the tomographic method, which include manifest Lorentz covariance, direct incorporation of positivity constraints, exhaustively complete polarization information, and new invariants free from frame conventions. For example, experimental data can determine the $entanglement$ $entropy$ of the production process, which is a model-independent invariant that measures the degree of coherence of the subprocess. We give reproducible numerical examples and provide a supplemental standalone computer code that implements the procedure. We also highlight a property of $complex$ $positivity$ that guarantees in a least-squares type fit that a local minimum of a $\chi^{2}$ statistic will be a global minimum: There are no isolated local minima. This property with an automated implementation of positivity promises to mitigate issues relating to multiple minima and convention-dependence that have been problematic in previous work on angular distributions.Comment: 25 pages, 3 figure

Neuroevolution on the Edge of Chaos

Echo state networks represent a special type of recurrent neural networks. Recent papers stated that the echo state networks maximize their computational performance on the transition between order and chaos, the so-called edge of chaos. This work confirms this statement in a comprehensive set of experiments. Furthermore, the echo state networks are compared to networks evolved via neuroevolution. The evolved networks outperform the echo state networks, however, the evolution consumes significant computational resources. It is demonstrated that echo state networks with local connections combine the best of both worlds, the simplicity of random echo state networks and the performance of evolved networks. Finally, it is shown that evolution tends to stay close to the ordered side of the edge of chaos.Comment: To appear in Proceedings of the Genetic and Evolutionary Computation Conference 2017 (GECCO '17

R&D Contracts in the Soviet Union

As the Soviet economy recovered from WWII devastation, economic officials struggled to design better incentives for promoting rapid technological progress in industry. They created model contracts for R&D work hoping to improve Soviet industry's relatively mediocre performance in using new technologies. This article describes the problems encountered in making model R&D contracts into an effective tool for promoting industrial innovation in the USSR. At the same time model R&D contracts were being established, a more radical reform, a "socialist license," was proposed by an official at the Soviet patent office (State Committee for Inventions and Discoveries), an agency whose top management came from the military-industrial complex. These proposed licenses gave R&D organizations greater financial benefits from new technologies by allowing licensing fees that related to cost savings and quality improvements. Economic officials, however, rejected the reform, viewing it as a challenge to the Communist Party's central planning authority. R&D contracts succeeded primarily in the educational ministry (MinVuz) and Academy of Sciences institutes, linking them more closely to industry, especially to facilities in the military-industrial complex.Während des Wiederaufbaus der UdSSR-Wirtschaft nach dem Zweitem Weltkrieg bemühten sich die sowjetischen Wirtschaftsfunktionäre, bessere Anreize durchzuführen um das Tempo des technologischen Fortschritts bei der Industrie zu erhöhen. Sie führten deshalb Musterverträge für Forschung und Entwicklungsarbeit ein mit der Hoffnung, die relativ mittelmäßige Leistung der Benutzung neuer Technologie in der UdSSR zu verbessern. Der folgende Artikel beschreibt die Musterverträge für Forschung und Entwicklungsarbeit und die Schwierigkeiten die sie begegneten während der Versuche, sie als Instrument der Verbesserung der industriellen Innovation einzuleiten. Während der Entwicklung dieser neuen Verträge erschien plötzlich eine radikaler Reformsvorschlag, eine sogenannte "sozialistische Lizenz". Sie kamen von einem Beamten beim sowjetischen Patentbüro (Staatskomitee für Erfindungen und Entdeckungen) das viele Spitzenmanager in der Rüstungsindustrie hervorbrachte. Mit der Aussicht auf eine sozialistische Lizenz, konnten Forschungs- und Entwicklungsorganisationen mehr von ihren neuen Technologien profitieren und ihre Lizenzgebühren auf Kostenersparnisse und Qualitätsverbesserungen zielen. Die Wirtschaftsbeamten erhoben einen heftigen Widerspruch dagegen, denn sie sahen diesen Vorschlag als gegen die zentrale Planlenkung gerichtet. Die neuen Forschungs- und Entwicklungsverträge hatten ihren größten Erfolg beim Erziehungsministerium (Minvuz) und bei den Instituten der Akademie der Wissenschaften und sie haben ihre Organisationen enger mit der Industrie verknüpft, besonders mit der Rüstungsindustrie