Results 11 to 20 of about 237,467 (314)
Difference of cross-spectral densities [PDF]
Optics Letters, 2014 Generally speaking, the difference between two cross-spectral densities (CSDs) does not represent a correlation function. We will furnish a sufficient condition so that such difference be a valid CSD. Using such a condition, we will show through some examples how new classes of CSDs can be generated.
González de Sande, Juan Carlos +3 more
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New Insights into the Lamb Shift: The Spectral Density of the Shift
Physics, 2022 In an atom, the interaction of a bound electron with the vacuum fluctuations of the electromagnetic field leads to complex shifts in the energy levels of the electron, with the real part of the shift corresponding to a shift in the energy level and the ...
G. Jordan Maclay
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On spectral density of Neumann matrices [PDF]
Physics Letters B, 2003 10 pages, 2 figures, LaTeX 2e; typos ...
Anatoly Konechny, D. M. Belov
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Accurate Truncations of Chain Mapping Models for Open Quantum Systems
Nanomaterials, 2021 The dynamics of open quantum systems are of great interest in many research fields, such as for the interaction of a quantum emitter with the electromagnetic modes of a nanophotonic structure.
Mónica Sánchez-Barquilla +1 more
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Monotone spectral density estimation [PDF]
The Annals of Statistics, 2011 We propose two estimators of a monotone spectral density, that are based on the periodogram. These are the isotonic regression of the periodogram and the isotonic regression of the log-periodogram. We derive pointwise limit distribution results for the proposed estimators for short memory linear processes and long memory Gaussian processes and also ...
Anevski, Dragi, Soulier, Philippe
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Assessing Granger-Causality in the Southern Humboldt Current Ecosystem Using Cross-Spectral Methods
Entropy, 2020 The southern Humboldt Current ecosystem is an important topic among researchers working on the drivers of pelagic species’ biological indicators.
Javier E. Contreras-Reyes +1 more
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Electromagnetohydrodynamic (EMHD) Flow in a Microchannel with Random Surface Roughness
Micromachines, 2023 This study investigates the effect of small random transverse wall roughness on electromagnetohydrodynamic (EMHD) flow is in a microchannel, employing the perturbation method based upon stationary random function theory.
Nailin Ma, Yanjun Sun, Yongjun Jian
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Stochastic modeling of algal bloom dynamics with delayed nutrient recycling
Mathematical Biosciences and Engineering, 2019 Using the discrete Markov chain, in this paper we develop a stochastic model for algal bloom, in which white noise terms are introduced to describe the e ects of environmental random fluctuations and time delay to account for the time needed in the ...
Xuehui Ji +3 more
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One-particle spectral densities and phase diagrams of one-dimensional proton conductors
Condensed Matter Physics, 2021 The equilibrium states of one-dimensional proton conductors in the systems with hydrogen bonds are investigated. Our extended hard-core boson lattice model includes short-range interactions between hydrogen ions, their transfer along the hydrogen bonds ...
R. Ya. Stetsiv
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The Spectral Density of a Difference of Spectral Projections [PDF]
Communications in Mathematical Physics, 2015 Let $H_0$ and $H$ be a pair of self-adjoint operators satisfying some standard assumptions of scattering theory. It is known from previous work that if $ $ belongs to the absolutely continuous spectrum of $H_0$ and $H$, then the difference of spectral projections $$D( )=1_{(-\infty,0)}(H- )-1_{(-\infty,0)}(H_0- )$$ in general is not compact and has
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