6 research outputs found
Noise Effects on the Complex Patterns of Abnormal Heartbeats
Patients at high risk for sudden death often exhibit complex heart rhythms in
which abnormal heartbeats are interspersed with normal heartbeats. We analyze
such a complex rhythm in a single patient over a 12-hour period and show that
the rhythm can be described by a theoretical model consisting of two
interacting oscillators with stochastic elements. By varying the magnitude of
the noise, we show that for an intermediate level of noise, the model gives
best agreement with key statistical features of the dynamics.Comment: 4 pages, 4 figures, RevTe
Critical Exponents from Five-Loop Strong-Coupling phi^4-Theory in 4- epsilon Dimensions
With the help of strong-coupling theory, we calculate the critical exponents
of O(N)-symmetric phi^4-theories in 4- epsilon dimensions up to five loops with
an accuracy comparable to that achieved by Borel-type resummation methods.Comment: Author Information under
http://www.physik.fu-berlin.de/~kleinert/institution.html . Latest update of
paper also at http://www.physik.fu-berlin.de/~kleinert/29
Critical Exponents From Five-Loop Strong-Coupling . . .
With the help of strong-coupling theory, we calculate the critical exponents of O(N)-symmetric # # dimensions up to five loops with an accuracy comparable to that achieved by Borel-type resummation methods. PACS number: 1110 1