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2The ATLAS Inner Detector is a composite tracking system consisting of silicon pixels, silicon strips and straw tubes in a 2 T magnetic field. Its installation was completed in August 2008 and the detector took part in data-taking with single LHC beams and cosmic rays. The initial detector operation, hardware commissioning and in-situ calibrations are described. Tracking performance has been measured with 7. 6 million cosmic-ray events, collected using a tracking trigger and reconstructed with mo…Read more
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2© 2014, The Author.: A search is presented for the production of new heavy quarks that decay to a Z boson and a third-generation Standard Model quark. In the case of a new charge +2/3 quark, the decay targeted is T → Zt, while the decay targeted for a new charge −1/3 quark is B → Zb. The search is performed with a dataset corresponding to 20.3 fb −1 of pp collisions at TeV recorded in 2012 with the ATLAS detector at the CERN Large Hadron Collider. Selected events contain a high transverse moment…Read more
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2© 2014, The Author.: A search for the neutral Higgs bosons predicted by the Minimal Supersymmetric Standard Model is reported. The analysis is performed on data from proton-proton collisions at a centre-of-mass energy of 8 TeV collected with the ATLAS detector at the Large Hadron Collider. The samples used for this search were collected in 2012 and correspond to integrated luminosities in the range 19.5-20.3 fb−1. The MSSM Higgs bosons are searched for in the τ τ final state. No significant exce…Read more
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2© 2015, The Author.: The production of a W boson decaying to eν or μν in association with a W or Z boson decaying to two jets is studied using 4.6 fb−1 of proton-proton collision data at √s =7 TeV recorded with the ATLAS detector at the LHC. The combined WW + WZ cross section is measured with a significance of 3.4σ and is found to be 68±7 ±19 pb, in agreement with the Standard Model expectation of 61.1±2.2 pb. The distribution of the transverse momentum of the dijet system is used to set limits …Read more
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Quantum Information in Relativity: The Challenge of QFT MeasurementsEntropy 24 4. 2022.Proposed quantum experiments in deep space will be able to explore quantum information issues in regimes where relativistic effects are important. In this essay, we argue that a proper extension of quantum information theory into the relativistic domain requires the expression of all informational notions in terms of quantum field theoretic (QFT) concepts. This task requires a working and practicable theory of QFT measurements. We present the foundational problems in constructing such a theory, …Read more
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207Gravitational decoherence: A thematic overviewAVS Quantum Science 4 015602. 2022.Gravitational decoherence (GD) refers to the effects of gravity in actuating the classical appearance of a quantum system. Because the underlying processes involve issues in general relativity (GR), quantum field theory (QFT), and quantum information, GD has fundamental theoretical significance. There is a great variety of GD models, many of them involving physics that diverge from GR and/or QFT. This overview has two specific goals along with one central theme:(i) present theories of GD based o…Read more
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7Frequently Asked Questions About DecoherenceInternational Journal of Theoretical Physics 41. 2002.We give a short, critical review of the issue of decoherence. We estab- lish the most general framework in which decoherence can be discussed, how it can be quantified and how it can be measured. We focus on environment induced decoher- ence and its degree of usefulness for the interpretation of quantum theory. We finally discuss the emergence of a classical world. An overall emphasis is given in pointing at common fallacies and misconceptions.
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7On the relation between quantum mechanical probabilities and event frequenciesAnnals of Physics 313 368-382. 2004.The probability ‘measure’ for measurements at two consecutive mo- ments of time is non-additive. These probabilities, on the other hand, may be determined by the limit of relative frequency of measured events, which are by nature additive. We demonstrate that there are only two ways to resolve this problem. The first solution places emphasis on the precise use of the concept of conditional probability for successive mea- surements. The physically correct conditional probabilities define additive…Read more
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40Quantum Theory: a Foundational ApproachCambridge University Press. 2023.This is a textbook on quantum mechanics. It is addressed to graduates and advanced undergraduates. The book presents quantum theory as a logically coherent system, placing stronger emphasis on the theory' s probabilistic structure and on the role of symmetries. It makes students aware of foundational problems from the very beginning, but at the same time, it urges them to adopt a pragmatic attitude towards the quantum formalism. The book consists of five parts. Part I is a review of classic…Read more
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55Mind–Body Interaction and Modern PhysicsFoundations of Physics 51 (3): 1-27. 2021.The idea that mind and body are distinct entities that interact is often claimed to be incompatible with physics. The aim of this paper is to disprove this claim. To this end, we construct a broad mathematical framework that describes theories with mind–body interaction (MBI) as an extension of current physical theories. We employ histories theory, i.e., a formulation of physical theories in which a physical system is described in terms of (i) a set of propositions about possible evolutions of t…Read more
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397The idea that mind and body are distinct entities that interact is often claimed to be incompatible with physics. The aim of this paper is to disprove this claim. To this end, we construct a broad mathematical framework that describes theories with mind-body interaction (MBI) as an extension of current physical theories. We employ histories theory, i.e., a formulation of physical theories in which a physical system is described in terms of (i) a set of propositions about possible evolution…Read more
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40Quantum Theory Without Hilbert SpacesFoundations of Physics 31 (11): 1545-1580. 2001.Quantum theory does not only predict probabilities, but also relative phases for any experiment, that involves measurements of an ensemble of systems at different moments of time. We argue, that any operational formulation of quantum theory needs an algebra of observables and an object that incorporates the information about relative phases and probabilities. The latter is the (de)coherence functional, introduced by the consistent histories approach to quantum theory. The acceptance of relative …Read more
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45Particle or Wave: The Evolution of the Concept of Matter in Modern PhysicsPrinceton University Press. 2008.'Particle or Wave' explains the origins and development of modern physical concepts about matter and the controversies surrounding them.
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115Classical Versus Quantum Probability in Sequential MeasurementsFoundations of Physics 36 (11): 1601-1661. 2006.We demonstrate in this paper that the probabilities for sequential measurements have features very different from those of single-time measurements. First, they cannot be modelled by a classical stochastic process. Second, they are contextual, namely they depend strongly on the specific measurement scheme through which they are determined. We construct Positive-Operator-Valued measures (POVM) that provide such probabilities. For observables with continuous spectrum, the constructed POVMs depend …Read more