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Gravitational waves are generated by accelerating masses. So, our planet, which is constantly accelerating towards the sun, is sending out a constant stream of gravitational waves. Just really small ones. Likewise, colliding neutron stars will emit a strong burst of gravitational waves. How strong? Well, if the stars were on the other side of our galaxy, a one meter bar on Earth would elongate by about 0.1am (attometer = 10-18m). 

orbit of an electron around a hydrogen atom (about 0.05nm),

In a light field, the amplitude (a measure of the brightness of the light) and the phase (which controls how to combine light fields) can't both be measured with absolute accuracy—even if you had the perfect measuring device. You can picture the problem as bunches of photons popping into and out of existence, causing the phase and amplitude of the of the light to jitter around. This doesn't add or subtract energy, but it does continuously redistributes the energy along the light beam.

GE’s Brand New 100W Equivalent LED Bulb Illuminates the Future of Lighting May 7, 2012 Engineers at GE’s NELA Park in East Cleveland, Ohio, have spent a century building better light bulbs. When NELA opened in 1911, it became the world’s first industrial park, a distinction that earned it a place on the National Register of Historic Places. But now a new kind of history is taking place at NELA, the kind that will soon dispatch the incandescent light bulb down the same road traveled by the LP and the VCR. “This is an evolution,” says Glenn Kuenzler, a lighting engineer at NELA. He and his team of researchers are making sure that the GE bulb, whose legacy stretches back to Edison, is fit to survive.

Wigner Distributions and How They Relate to the Light Field

Abstract In wave optics, the Wigner distribution and its Fourier dual, the ambiguity function, are important tools in optical system simulation and analysis. The light field fulfills a similar role in the computer graphics community. In this paper, we establish that the light field as it is used in computer graphics is equivalent to a smoothed Wigner distribution and that these are equivalent to the raw Wigner distribution under a geometric optics approximation. Using this insight, we then explore two recent contributions: Fourier slice photography in computer graphics and wavefront coding in optics, and we examine the similarity between explanations of them using Wigner distributions and explanations of them using light fields. Understanding this long-suspected equivalence may lead to additional insights and the productive exchange of ideas between the two fields.

In the late 19th century, luminiferous aether, æther or ether, meaning light-bearing aether, was the postulated medium for the propagation of light.

Dung beetles just climbed another ladder on the animal coolness scale – they are the only known species to navigate via the Milky Way. The tiny insects can orient themselves to the bright stripe of light generated by our galaxy, and move in a line relative to it, according to experiments conducted in South Africa.

Energy of Photon

A photon is characterized by either a wavelength, denoted by λ or equivalently an energy, denoted by E. There is an inverse relationship between the energy of a photon (E) and the wavelength of the light (λ) given by the equation: