22,482 research outputs found
Benchmarks of the full configuration interaction, Monte Carlo shell model, and no-core full configuration methods
We report no-core solutions for properties of light nuclei with three
different approaches in order to assess the accuracy and convergence rates of
each method. Full configuration interaction (FCI), Monte Carlo shell model
(MCSM) and no core full configuration (NCFC) approaches are solved separately
for the ground state energy and other properties of seven light nuclei using
the realistic JISP16 nucleon-nucleon interaction. The results are consistent
among the different approaches. The methods differ significantly in how the
required computational resources scale with increasing particle number for a
given accuracy.Comment: 19 pages, 14 figures, 6 table
Peculiar mean velocity profiles within a porous bed of an open channel
Peer reviewedPublisher PD
Quantum Zeno Effect for Exponentially Decaying Systems
The quantum Zeno effect -- suppression of decay by frequent measurements --
was believed to occur only when the response of the detector is so quick that
the initial tiny deviation from the exponential decay law is detectable.
However, we show that it can occur even for exactly exponentially decaying
systems, for which this condition is never satisfied, by considering a
realistic case where the detector has a finite energy band of detection. The
conventional theories correspond to the limit of an infinite bandwidth. This
implies that the Zeno effect occurs more widely than expected so far.Comment: 4 pages, 3 figure
Photon-energy dissipation caused by an external electric circuit in "virtual" photo-excitation processes
We consider generation of an electrical pulse by an optical pulse in the
``virtual excitation'' regime. The electronic system, which is any
electro-optic material including a quantum well structure biased by a dc
electric field, is assumed to be coupled to an external circuit. It is found
that the photon frequency is subject to an extra red shift in addition to the
usual self-phase modulation, whereas the photon number is conserved. The Joule
energy consumed in the external circuit is supplied only from the extra red
shift.Comment: 4 pages, 1 fugur
Appearance and Stability of Anomalously Fluctuating States in Shor's Factoring Algorithm
We analyze quantum computers which perform Shor's factoring algorithm, paying
attention to asymptotic properties as the number L of qubits is increased.
Using numerical simulations and a general theory of the stabilities of
many-body quantum states, we show the following: Anomalously fluctuating states
(AFSs), which have anomalously large fluctuations of additive operators, appear
in various stages of the computation. For large L, they decohere at anomalously
great rates by weak noises that simulate noises in real systems. Decoherence of
some of the AFSs is fatal to the results of the computation, whereas
decoherence of some of the other AFSs does not have strong influence on the
results of the computation. When such a crucial AFS decoheres, the probability
of getting the correct computational result is reduced approximately
proportional to L^2. The reduction thus becomes anomalously large with
increasing L, even when the coupling constant to the noise is rather small.
Therefore, quantum computations should be improved in such a way that all AFSs
appearing in the algorithms do not decohere at such great rates in the existing
noises.Comment: 11 figures. A few discussions were added in verion 2. Version 3 is
the SAME as version 2; only errors during the Web-upload were fixed. Version
4 is the publised version, in which several typos are fixed and the reference
list is update
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Biomarkers of Inflammation and Fibrosis in Kawasaki Disease Patients Years After Initial Presentation With Low Ejection Fraction.
Background Coronary artery aneurysms and myocarditis are well-recognized complications of Kawasaki disease (KD) but no systematic evaluation of the consequences of myocarditis has been performed in the subset presenting with low ejection fraction (EF). We postulated that more severe myocardial inflammation as evidenced by low EF during the acute phase could lead to late myocardial fibrosis. Methods and Results We measured the carboxyterminal propeptide of procollagen type I (PIPC), soluble suppressor of tumorigenicity 2, galectin-3 (Gal-3), growth-differentiation factor-15, and calprotectin by ELISA in late convalescent blood samples from 16 KD patients who had an EF â€55% on their initial echocardiogram. Results were compared with samples from sex- and age-matched KD patients with initial EF >60%. In the univariate analysis, the median Gal-3 and PIPC levels in the low EF group were significantly higher than those in the normal EF group (Gal-3: low EF 6.216 versus normal EF 4.976 mg/dL P=0.038, PIPC: low EF 427.4 versus normal EF 265.2 mg/dL, P=0.01). In a multivariable analysis, there were significant differences for Gal-3 and PIPC levels between the low and normal EF groups, adjusting for age, sex, and worst z score. Conclusions Convalescent KD patients with a history of low EF during the acute illness had significantly elevated levels of Gal-3 and PIPC when compared with matched-control KD patients with normal EF. These findings raise concern for myocardial fibrosis as a potential late sequela of the more severe myocarditis experienced by a subset of KD patients during the acute phase
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