Complex lapse, complex action, and path integrals
نویسندگان
چکیده
منابع مشابه
Complex lapse, complex action, and path integrals.
Abstract. Imaginary time is often used in quantum tunnelling calculations. This article advocates a conceptually sounder alternative: complex lapse. In the “3+1” action for the Einstein gravitational field minimally coupled to a Klein-Gordon field, allowing the lapse function to be complex yields a complex action which generates both the usual Lorentzian theory and its Riemannian analogue, and ...
متن کاملEffective descriptions of complex quantum systems: path integrals and operator ordering problems
We study certain aspects of the effective, occasionally called collective, description of complex quantum systems within the framework of the path integral formalism, in which the environment is integrated out. Generalising the standard Feynman-Vernon Caldeira-Leggett model to include a non-linear coupling between “particle” and environment, and considering a particular spectral density of the ...
متن کاملPath Integrals Without Integrals∗
Recently, we have developed an efficient recursive approach for analytically calculating the short-time expansion of the propagator to extremely high orders for a general many-body quantum system. Here we give brief overview of this approach and then demonstrate application of this technique by numerically studying the thermodynamical properties of a rotating ideal Bose gas of Rb atoms in an an...
متن کاملToward Picard-Lefschetz Theory of Path Integrals, Complex Saddles and Resurgence
We show that the semi-classical analysis of generic Euclidean path integrals necessarily requires complexification of the action and measure, and consideration of complex saddle solutions. We demonstrate that complex saddle points have a natural interpretation in terms of the Picard-Lefschetz theory. Motivated in part by the semi-classical expansion of QCD with adjoint matter on R × S, we study...
متن کاملProtein Kinase A Catalytic Subunit Primed for Action: Time-Lapse Crystallography of Michaelis Complex Formation.
The catalytic subunit of the cyclic AMP-dependent protein kinase A (PKAc) catalyzes the transfer of the γ-phosphate of bound Mg2ATP to a serine or threonine residue of a protein substrate. Here, time-lapse X-ray crystallography was used to capture a series of complexes of PKAc with an oligopeptide substrate and unreacted Mg2ATP, including the Michaelis complex, that reveal important geometric r...
متن کاملذخیره 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: Physical Review D
سال: 1996
ISSN: 0556-2821,1089-4918
DOI: 10.1103/physrevd.53.5664