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991.
Generic relevant deformations of Einstein's gravity theory contain additional degrees of freedom that have a multifaceted stabilization dynamics on curved spacetimes. We show that these relevant degrees of freedom are self-protected against unitarity violations by the formation of classical field lumps that eventually merge to a new background geometry. The transition is heralded by the massive decay of the original vacuum and evolves through a strong coupling regime. This process fits in the recently proposed classicalization mechanism and extends it further to free field dynamics on curved backgrounds. 相似文献
992.
Keil R Perez-Leija A Dreisow F Heinrich M Moya-Cessa H Nolte S Christodoulides DN Szameit A 《Physical review letters》2011,107(10):103601
Coherent states and their generalizations, displaced Fock states, are of fundamental importance to quantum optics. Here we present a direct observation of a classical analogue for the emergence of these states from the eigenstates of the harmonic oscillator. To this end, the light propagation in a Glauber-Fock waveguide lattice serves as equivalent for the displacement of Fock states in phase space. Theoretical calculations and analogue classical experiments show that the square-root distribution of the coupling parameter in such lattices supports a new family of intriguing quantum correlations not encountered in uniform arrays. Because of the broken shift invariance of the lattice, these correlations strongly depend on the transverse position. Consequently, quantum random walks with this extra degree of freedom may be realized in Glauber-Fock lattices. 相似文献
993.
Cribier M Fechner M Lasserre T Letourneau A Lhuillier D Mention G Franco D Kornoukhov V Schönert S 《Physical review letters》2011,107(20):201801
Several observed anomalies in neutrino oscillation data can be explained by a hypothetical fourth neutrino separated from the three standard neutrinos by a squared mass difference of a few eV(2). We show that this hypothesis can be tested with a PBq (ten kilocurie scale) (144)Ce or (106)Ru antineutrino beta source deployed at the center of a large low background liquid scintillator detector. In particular, the compact size of such a source could yield an energy-dependent oscillating pattern in event spatial distribution that would unambiguously determine neutrino mass differences and mixing angles. 相似文献
994.
André G. Edelmann Stefan F. Helfert Jürgen Jahns 《Optical and Quantum Electronics》2011,42(8):531-540
In this article, we examine spectral transmission characteristics based on the self-imaging effect in plasmonic multimode
waveguides. For the analysis, we calculate the correlation between an input field and the field in the self-imaging plane.
We perform full vectorial computations using the Method of Lines as numerical method. The resulting transmission profile is
discussed with regards to the attenuation, the even and odd mode sets and for several structural parameters of the plasmonic
waveguide. The introduced transmission characteristic may offer the opportunity for the implementation of filtering operations
in plasmonic waveguides. 相似文献
995.
Amrutha Prabodh Yichuan Wang Stephan Sinn Paolo Albertini Christian Spies Eduard Spuling Liu-Pan Yang Wei Jiang Stefan Brse Frank Biedermann 《Chemical science》2021,12(27):9420
Fluorescence-detected circular dichroism (FDCD) spectroscopy is applied for the first time to supramolecular host–guest and host–protein systems and compared to the more known electronic circular dichroism (ECD). We find that FDCD can be an excellent choice for common supramolecular applications, e.g. for the detection and chirality sensing of chiral organic analytes, as well as for reaction monitoring. Our comprehensive investigations demonstrate that FDCD can be conducted in favorable circumstances at much lower concentrations than ECD measurements, even in chromophoric and auto-emissive biofluids such as blood serum, overcoming the sensitivity limitation of absorbance-based chiroptical spectroscopy. Besides, the combined use of FDCD and ECD can provide additional valuable information about the system, e.g. the chemical identity of an analyte or hidden aggregation phenomena. We believe that simultaneous FDCD- and ECD-based chiroptical characterization of emissive supramolecular systems will be of general benefit for characterizing fluorescent, chiral supramolecular systems due to the higher information content obtained by their combined use.Fluorescence-detected circular dichroism (FDCD) spectroscopy is applied for the first time to supramolecular host–guest and host–protein systems and compared to the more known electronic circular dichroism (ECD). 相似文献
996.
Stefan Hubert Liam Pettigrew Thorben Helmers Ulrich Mießner Frauke Groß Norbert Räbiger Antonio Delgado 《PAMM》2014,14(1):811-812
This study introduces the concept of computer modelling and simulation of complex bioprocesses and systems using an approach that combines the reference net formalism with machine learning and optimisation techniques. Reference nets are an extension of high level Petri Nets, which can be used as a central visualisation and modelling tool. The net-in-net paradigm used by reference nets makes it possible to model complex processes, such as those found in the food and beverage industry. A plugin/interface system based on the java programming language allows implementation of advanced mathematical modelling techniques at specific points in entire system simulations. Separate optimisation tools can also run and modify existing reference net models for fast solutions to efficiency problems. We present an example system that simulates a specific section of a beer brewery using the reference net formalism, which is optimised using a genetic algorithm. We show in detail how the different software packages can be combined for a simulation based optimisation approach. The optimisation technique specifically addresses the wastewater pollution load in regard to its chemical oxygen demand. A beer brewery was chosen as an example for this study due to the constantly increasing requirements to lower energy and water consumption in this industry. One possibility to lower the energy and water demands is to effectively treat wastewater produced by the brewery, which can introduce cost savings by providing recycled water and biogas. Most approaches to wastewater treatment are end-of-pipe solutions that do not consider the brewery as a whole. A brewery contains many processes that can be running concurrently and interacting with one another (e.g. brewing, clean-in-place and bottling) with each process producing varying amounts of wastewater with different pollution loads. Optimisation of the scheduling of the different processes with respect to the wastewater production will allow for more effective wastewater treatment, and therefore cost and energy savings. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
997.
Carmen Sguazzo Mohamed Harhash Matthias Grafenhorst Heinz Palkowski Stefan Hartmann 《PAMM》2014,14(1):245-246
Composite materials are widely used in different industrial fields, because of their good formability and their high strength to weight ratio. In the present work a triple-layered sandwich composite is investigated. Experimental tests at room temperature are carried out for the materials constituting the composite. A finite element model of a deep-drawing process of the composite is performed, where a finite strain constitutive model for the metal part, with material parameters calibrated to uniaxial tensile tests, has been implemented. Experimental results are compared to the numerical simulations in view of validation purposes. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
998.
The general idea of moving mesh approaches is to improve the approximation quality and the numerical performance by redistributing a fixed number of discretization points. This is called rrefinement. The classical approaches are applied to partial differential equations on fixed domains. An extension to time-dependent (expanding) domains is presented. (© 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
999.
Let N be an irreducible, compact 3-manifold with empty or toroidal boundary which is not a closed graph manifold. We show that it follows from the work of Agol, Kahn–Markovic and Przytycki–Wise that π1(N) admits a cofinal filtration with ‘fast’ growth of Betti numbers as well as a cofinal filtration of π1(N) with ‘slow’ growth of ranks. 相似文献
1000.
Barbu Vlad Stefan Beltaief Slim Pergamenshchikov Sergey 《Statistical Inference for Stochastic Processes》2019,22(2):187-231
Statistical Inference for Stochastic Processes - We consider the nonparametric robust estimation problem for regression models in continuous time with semi-Markov noises. An adaptive model... 相似文献