Filtering of Wide Sense Stationary Quantum Stochastic Processes
نویسنده
چکیده
We introduce a concept of a quantum wide sense stationary process taking values in a C*-algebra and expected in a sub-algebra. The power spectrum of such a process is defined, in analogy to classical theory, as a positive measure on frequency space taking values in the expected algebra. The notion of linear quantum filters is introduced as some simple examples mentioned. 1 Spectral Analysis of WSS Quantum Processes In the following we consider processes depending on a continuous time variable t ∈ R: the frequency domain will be denoted as R̂ for distinction. Therefore we have the Fourier transform conventions f̂ (ν) = ∫ R e tν f (t) dt, f (t) =
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