Density-operator evolution: Complete positivity and the Keldysh real-time expansion

نویسندگان
چکیده

برای دانلود باید عضویت طلایی داشته باشید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

2 Complete statistical description : the density operator

Statistical mechanics relies on the complete though probabilistic description of a system in terms of all the microscopic variables. Its object is to derive therefrom static and dynamic properties involving some reduced set of variables. The elimination of the irrelevant variables is guided by the maximum entropy criterion, which produces the probability law carrying the least amount of informa...

متن کامل

Factorizing the Time Evolution Operator

There is a widespread belief in the quantum physical community, and in textbooks used to teach Quantum Mechanics, that it is a difficult task to apply the time evolution operator e itˆH / on an initial wave function. That is to say, because the hamiltonian operator generally is the sum of two operators, then it is a difficult task to apply the time evolution operator on an initial wave function...

متن کامل

Linear-Time Complete Positivity Detection and Decomposition of Sparse Matrices

A matrix X is called completely positive if it allows a factorisation X = ∑ b∈B bb T with nonnegative vectors b. These matrices are of interest in optimisation, as it has been found that several combinatorial and quadratic problems can be formulated over the cone of completely positive matrices. The difficulty is that checking complete positivity is NP-hard. Finding a factorisation of a general...

متن کامل

ASYMPTOTICS OF EXPANSION OF THE EVOLUTION OPERATOR KERNEL IN POWERS OF TIME INTERVAL ∆t

The upper bound for asymptotic behavior of the coefficients of expansion of the evolution operator kernel in powers of the time interval ∆t was obtained. It is found that for the nonpolynomial potentials the coefficients may increase as n!. But increasing may be more slow if the contributions with opposite signs cancel each other. Particularly, it is not excluded that for number of the potentia...

متن کامل

A new perturbative expansion of the time evolution operator associated with a quantum system

A novel expansion of the evolution operator associated with a – in general, time-dependent – perturbed quantum Hamiltonian is presented. It is shown that it has a wide range of possible realizations that can be fitted according to computational convenience or to satisfy specific requirements. As a remarkable example, the quantum Hamiltonian describing a laser-driven trapped ion is studied in de...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: SciPost Physics

سال: 2019

ISSN: 2542-4653

DOI: 10.21468/scipostphys.7.1.012