다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

On September 14, 2015 at 09:50:45 UTC the two detectors of the Laser Interferometer Gravitational-Wave Observatory simultaneously observed a transient gravitational-wave signal. The signal sweeps upwards in frequency from 35 to 250 Hz with a peak gravitational-wave strain of 1.0×10(-21). It matches the waveform predicted by general relativity for the inspiral and merger of a pair of black holes and the ringdown of the resulting single black hole. The signal was observed with a matched-filter signal-to-noise ratio of 24 and a false alarm rate estimated to be less than 1 event per 203,000 years, equivalent to a significance greater than 5.1σ. The source lies at a luminosity distance of 410(-180)(+160)  Mpc corresponding to a redshift z=0.09(-0.04)(+0.03). In the source frame, the initial black hole masses are 36(-4)(+5)M⊙ and 29(-4)(+4)M⊙, and the final black hole mass is 62(-4)(+4)M⊙, with 3.0(-0.5)(+0.5)M⊙c(2) radiated in gravitational waves. All uncertainties define 90% credible intervals. These observations demonstrate the existence of binary stellar-mass black hole systems. This is the first direct detection of gravitational waves and the first observation of a binary black hole merger.

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The Observation of Gravitational Waves from a Binary Black Hole Merger

Recent interest in aspects common to quantum information and condensed matter has prompted a flurry of activity at the border of these disciplines that were far distant until a few years ago. Numerous interesting questions have been addressed so far. Here an important part of this field, the properties of the entanglement in many-body systems, are reviewed. The zero and finite temperature properties of entanglement in interacting spin, fermion, and boson model systems are discussed. Both bipartite and multipartite entanglement will be considered. In equilibrium entanglement is shown tightly connected to the characteristics of the phase diagram. The behavior of entanglement can be related, via certain witnesses, to thermodynamic quantities thus offering interesting possibilities for an experimental test. Out of equilibrium entangled states are generated and manipulated by means of many-body Hamiltonians.

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Entanglement in many-body systems

Squeezed states of the electromagnetic field have been generated by nondegenerate four-wave mixing due to Na atoms in an optical cavity. The optical noise in the cavity, comprised of primarily vacuum fluctuations and a small component of spontaneous emission from the pumped Na atoms, is amplified in one quadrature of the optical field and deamplified in the other quadrature. These quadrature components are measured with a balanced homodyne detector. The total noise level in the deamplified quadrature drops below the vacuum noise level.

Observation of squeezed states generated by four-wave mixing in an optical cavity

a ) p. 131 The discussion between eqs. (5.14) and (5.15) is incorrect (dA should be made as large as possible!). b ) p. 256 In the figure, the numbers 6) and 7) occur twice. c ) p. 292 At the end of section 12.5, it should be the space of isospectral 0Hermitian matrices. d ) p. 306 A ”Tr” is missing in eq. (13.43). e ) p. 327, Eq. (14.64b) is 〈Trρ〉B = N(14N+10) (5N+1)(N+3) should be 〈Trρ〉B = 8N+7 (N+2)(N+4)

Geometry of Quantum States: Frontmatter

We investigate two schemes of quantum teleportation with a W state, which belongs to a different class from the Greenberger–Horne–Zeilinger class. In the first scheme, the W state is shared by three parties, one of whom, called a sender, performs a Bell measurement. It is shown that the quantum information of an unknown state is split between two parties and recovered with a certain probability. In the second scheme, a sender takes two particles of the W state and performs positive operator valued measurements. For the two schemes, we calculate the success probability and the average fidelity. We show that the average fidelity of the second scheme cannot exceed that of the first one.

https://iopscience.iop.org/article/10.1088/1367-2630/5/1/136/pdf

Quantum teleportation via a W state

Alice, Bob and Charlie are three remote parties Alice and Bob share the classical knowledge of a secret qubit state We consider the following question: 'how can Alice and Bob jointly prepare the qubit state for Charlie?' Two different protocols are proposed for such a joint remote state preparation The first protocol uses a single GHZ state while the second one uses a pair of EPR states as the quantum channel whose entanglement is not necessarily maximal

https://iopscience.iop.org/article/10.1088/0953-4075/41/9/095501/pdf

Joint remote state preparation

We extend the concept of negativity, a good measure of entanglement for bipartite pure states, to mixed states by means of the convex-roof extension. We show that the measure does not increase under local quantum operations and classical communication, and derive explicit formulas for the entanglement measure of isotropic states and Werner states, applying the formalism presented by Vollbrecht and Werner [Phys. Rev. A 64, 062307 (2001)].

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Convex-roof extended negativity as an entanglement measure for bipartite quantum systems

We describe here the first selective synthesis of (CH[sub 3])[sub 2]C[sub 60], i.e., the simplest dialkylated derivative of C[sub 60]. The selectivity is achieved by electrochemical control of the charge, n, on C[sub 60][sup n[minus]], generated prior to methylation. The addition of methyl iodide to a solution of C[sub 60][sup 2[minus]], generated by controlled-potential bulk electroreduction of C[sub 60] in an aprotic solvent, yields predominantly a dimethylated product and free iodide in solution. The presented preparation method provides a convenient route for controlled alkylation of C[sub 60] in large quantities and opens the door for selective fullerene functionalization with other addends. 20 refs., 1 fig.

Selective electrosynthesis of dimethylfullerene [(CH3)2C60]: a novel method for the controlled functionalization of fullerenes

©2000 The American Physical Society 

URL: http://link.aps.org/abstract/PRA/v63/e012305
DOI: 10.1103/PhysRevA.63.012305 
PACS: 03.67.-a, 03.65.Ta, 42.50.-p

Jaewan Kim

Papers

Quantum teleportation via a W state

Joint remote state preparation

Convex-roof extended negativity as an entanglement measure for bipartite quantum systems

Selective electrosynthesis of dimethylfullerene [(CH3)2C60]: a novel method for the controlled functionalization of fullerenes

Quantum teleportation and Bell’s inequality using single-particle entanglement