There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

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.

/pdf/the-observation-of-gravitational-waves-from-a-binary-black-58srpupgg9.pdf

The Observation of Gravitational Waves from a Binary Black Hole Merger

From the Publisher: 
The accessible presentation of this book gives both a general view of the entire computer vision enterprise and also offers sufficient detail to be able to build useful applications. Users learn techniques that have proven to be useful by first-hand experience and a wide range of mathematical methods. A CD-ROM with every copy of the text contains source code for programming practice, color images, and illustrative movies. Comprehensive and up-to-date, this book includes essential topics that either reflect practical significance or are of theoretical importance. Topics are discussed in substantial and increasing depth. Application surveys describe numerous important application areas such as image based rendering and digital libraries. Many important algorithms broken down and illustrated in pseudo code. Appropriate for use by engineers as a comprehensive reference to the computer vision enterprise.

Computer vision : a modern approach = 计算机视觉 : 一种现代的方法

Researchers demonstrate the ability to multiplex and transfer data between twisted beams of light with different amounts of orbital angular momentum — a development that provides new opportunities for increasing the data capacity of free-space optical communications links.

/pdf/terabit-free-space-data-transmission-employing-orbital-47zsgn5cdx.pdf

Terabit free-space data transmission employing orbital angular momentum multiplexing

We demonstrate high-dimensional entanglement with ≈ 6 qubits per photon via mode-locked biphoton frequency comb. Hong-Ou-Mandel quantum revival is observed with 61 time-bins and 99.8% visibility.

High-Dimensional Energy-Time Entanglement up to 6 Qubits per Photon through Biphoton Frequency Comb

A new configuration for optical coherence tomography is proposed that utilizes a phase-conjugate amplifier in conjunction with a Michelson interferometer to detect interference between two classical light fields with a non-zero phase-sensitive cross correlation. This imaging configuration - which we call phase-conjugate optical coherence tomography (PC-OCT) - shares the same factor-of-two axial resolution improvement and cancellation of even-order dispersion terms that are the key features of quantum optical coherence tomography, but without the necessity for non-classical signal and reference beams. Under appropriate conditions, PC-OCT can achieve a signal-to-noise ratio that is comparable to that of conventional optical coherence tomography.

Optical coherence tomography with phase-sensitive light

The author corrects errors made in the above titled paper (ibid., vol. 15, no. 6, pp. 1547-1569, Nov./Dec. 09), and withdraws the Note Added in Proof.

Corrections to “The Quantum Theory of Optical Communications” [Nov/Dec 09 1547-1569]

Recently, Chen \em et al \rm.\ [Phys. Rev. A 84, 033835 (2011)] reported observation of anticorrelated photon coincidences in a Mach-Zehnder interferometer whose input light came from a mode-locked Ti:sapphire laser that had been rendered spatially incoherent by passage through a rotating ground-glass diffuser. They provided a quantum-mechanical explanation of their results, which ascribes the anticorrelation to two-photon interference. They also developed a classical-light treatment of the experiment, and showed that it was incapable of explaining the anticorrelation behavior. Here we show that semiclassical photodetection theory---i.e., classical electromagnetic fields plus photodetector shot noise---does indeed explain the anticorrelation found by Chen \em et al \rm.\ The key to our analysis is proper accounting for the disparate time scales associated with the laser's pulse duration, the speckle-correlation time, the interferometer's differential delay, and the duration of the photon-coincidence gate. Our result is consistent with the long-accepted dictum that laser light which has undergone linear-optics transformations is classical-state light, so that the quantum and semiclassical theories of photodetection yield quantitatively identical results for its measurement statistics. The interpretation provided by Chen \em et al \rm. for their observations implicitly contradicts that dictum

Comment on "Observation of anticorrelation in incoherent thermal light fields"

Erratum: LADAR resolution improvement using receivers enhanced with squeezed-vacuum injection and phase-sensitive amplification (Journal of the Optical Society of America B: Optical Physics (2010) 27 (A63-A72))

Jeffrey H. Shapiro

Papers

High-Dimensional Energy-Time Entanglement up to 6 Qubits per Photon through Biphoton Frequency Comb

Optical coherence tomography with phase-sensitive light

Corrections to “The Quantum Theory of Optical Communications” [Nov/Dec 09 1547-1569]

Comment on "Observation of anticorrelation in incoherent thermal light fields"

Erratum: LADAR resolution improvement using receivers enhanced with squeezed-vacuum injection and phase-sensitive amplification (Journal of the Optical Society of America B: Optical Physics (2010) 27 (A63-A72))