Gravitational “sparkles” for passive gravitational time of flight correlation imaging arrays
Someone wished that my holidays would “sparkle”. I think about gravitational noise every day and have for a long time. Now I will think about gravitational “sparkle” during the holidays and beyond.
Sferics, sparks, seismic events, explosions, cracks, radioactive decays, shock waves, collisions. Gravity is mostly collisions and things bumping around. They mostly crack and crackle, but I have never seriously looked at “sparkle”. The stars will “twinkle”. In physics the time derivatives are called position, velocity, acceleration, jerk, snap, crackle and pop (I kid you not).
Maybe gravity could be “sparkles” in the soft x-ray regions down through ultraviolet and up through gamma and cosmic rays, neutrinos and muon decays. Many things cause tiny, brief forces, which add up. If the timing is right. But the shape has to be right as well. Lasers have “speckles” and many things have “scattering events”. Electrical noise can sound like “popcorn” or it can “flicker”. There is “shot noise” and “spikes”.
All of those are simple, if one uses higher sampling rates. There is “transient noise”, “fluctuations”, ‘scratching noise” and triboelectric effects. Barkhausen noise. Even fluorescence is tiny sharp events. Even “hum” and “buzz” have nonlinear effects. Two waves, almost identical in frequency will add and subtract to make very fast changes. Femtosecond lasers are quick and often asymmetric.
Lasers use “high harmonic generation” to reach the soft x-ray and extreme ultraviolet where the gravitational field at the earth’s surface acts. I am reminded of one of my oldest memories about gravitational radiation: “In general, we expect that there will be no gravitational radiation from a particle unless the third derivative of its position is nonzero.” and “the lowest order radiation is quadrupole radiation”, “the radiated power depends on the third time derivative of the mass quadrupole moment.” So there is movement, rotation, vibration and oscillation – all nonlinear. So brief we hardly notice, or see them. So many, they are hard to record and count. But not impossible.
Record fast enough and it is possible to do “time of flight” and “synthetic aperture” with gravitational events on earth and in the solar system. And ( Gravitational “sparkles” for passive gravitational time of flight correlation imaging arrays ) any where.
One brief KiloElectronVolt event is worth a million milliElectronVolt photons – if you are fast enough.
