30 research outputs found

    Complex Classical Fields: A Framework for Reflection Positivity

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    We explore a framework for complex classical fields, appropriate for describing quantum field theories. Our fields are linear transformations on a Hilbert space, so they are more general than random variables for a probability measure. Our method generalizes Osterwalder and Schrader's construction of Euclidean fields. We allow complex-valued classical fields in the case of quantum field theories that describe neutral particles. From an analytic point-of-view, the key to using our method is reflection positivity. We investigate conditions on the Fourier representation of the fields to ensure that reflection positivity holds. We also show how reflection positivity is preserved by various space-time compactifications of Euclidean space.Comment: 30 page

    Complex classical fields: A framework for reflection positivity

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    We explore a framework for complex classical fields, appropriate for describing quantum field theories. Our fields are linear transformations on a Hilbert space, so they are more general than random variables for a probability measure. Our method generalizes Osterwalder and Schrader's construction of Euclidean fields. We allow complex-valued classical fields in the case of quantum field theories that describe neutral particles. From an analytic point-of-view, the key to using our method is reflection positivity. We investigate conditions on the Fourier representation of the fields to ensure that reflection positivity holds. We also show how reflection positivity is preserved by various space-time compactifications of Euclidean space

    Complex classical fields and partial wick rotations

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    We study some examples of complex, classical, scalar fields within the new framework that we introduced in a previous work. In these particular examples, we replace the usual functional integral by a complex functional arising from partial Wick rotation of a quantum field. We generalize the Feynman-Kac relation to this setting, and use it to establish the spectral condition on a cylinder. We also consider positive-tempera

    Key Points for Curbing Cardiopulmonary Bypass Inflammation

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    ABSTRACT PURPOSE: Cardiopulmonary bypass (CPB) procedures are thought to activate systemic inflammatory reaction syndrome (SIRS). Strategies to curb systemic inflammation have been previously described. However, none of them is adequate, since "curbing" the extent of the inflammatory response requires a multimodal approach. The aim of the present mini-review is to discuss the main key points about the main principles in cardiopulmonary bypass curbing inflammation. METHODS: No systematic literature search (MEDLINE) and extracted data from the accumulated experience of the authors. The preconceived idea of an association between severe inflammation and coagulation disorders is reviewed. Also, some fundamental concepts, CPB inflammatory biomarkers, the vasoplegic syndrome and the need forindividual CPB protocols for children, diabetes and old patients, are discussed. CONCLUSION: The ways in which surgical technique (atraumatic vein harvest, biocompatibility and shear resistance of the circuit, monitoring, minimizing organ ischemia, minimal cross-clamping trauma, and blood management) are thought to curb SIRS induced by CPB and affect positively the patient outcome.Improved patient outcomes are strongly associated with these modalities of care, more than single or combinatorial drug strategies (aprotinin, tranexamic acid, pentoxifylline) or CPB modalities (minicircuits, heparin-coated circuits, retrograde autologous prime)

    All-cause mortality in the cohorts of the Spanish AIDS Research Network (RIS) compared with the general population: 1997Ɓ2010

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    Abstract Background: Combination antiretroviral therapy (cART) has produced significant changes in mortality of HIVinfected persons. Our objective was to estimate mortality rates, standardized mortality ratios and excess mortality rates of cohorts of the AIDS Research Network (RIS) (CoRIS-MD and CoRIS) compared to the general population. Methods: We analysed data of CoRIS-MD and CoRIS cohorts from 1997 to 2010. We calculated: (i) all-cause mortality rates, (ii) standardized mortality ratio (SMR) and (iii) excess mortality rates for both cohort for 100 personyears (py) of follow-up, comparing all-cause mortality with that of the general population of similar age and gender. Results: Between 1997 and 2010, 8,214 HIV positive subjects were included, 2,453 (29.9%) in CoRIS-MD and 5,761 (70.1%) in CoRIS and 294 deaths were registered. All-cause mortality rate was 1.02 (95% CI 0.91-1.15) per 100 py, SMR was 6.8 (95% CI 5.9-7.9) and excess mortality rate was 0.8 (95% CI 0.7-0.9) per 100 py. Mortality was higher in patients with AIDS, hepatitis C virus (HCV) co-infection, and those from CoRIS-MD cohort (1997. Conclusion: Mortality among HIV-positive persons remains higher than that of the general population of similar age and sex, with significant differences depending on the history of AIDS or HCV coinfection

    Observation of gravitational waves from the coalescence of a 2.5−4.5 M⊙ compact object and a neutron star

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    COMPLEX CLASSICAL FIELDS AND PARTIAL WICK ROTATIONS

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    Abstract. We study some examples of complex, classical, scalar fields within the new framework that we introduced in a previous work. In these particular examples, we replace the usual functional integral by a complex functional arising from partial Wick rotation of a quantum field. We generalize the Feynman-Kac relation to this setting, and use it to establish the spectral condition on a cylinder. We also consider positive-temperature states. Dedicated to Arthur Strong Wightman
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