Rainer Weiss Quotes

Wie meine Träume nach Dir schrein. Wir sind uns mühsam fremd geworden, Jetzt will es mir die Seele morden Dies arme, bange Einsamsein. Kein Hoffen, das die Segel bauscht. Nur diese weite, weisse Stille, In die mein thatenloser Wille In athemlosem Bangen lauscht.

There are only two types of waves that can travel across the universe bringing us information about things far away: electromagnetic waves (which include light, X-rays, gamma rays, microwaves, radio waves…); and gravitational waves. Electromagnetic waves consist of oscillating electric and magnetic forces that travel at light speed. When they impinge on charged particles, such as the electrons in a radio or TV antenna, they shake the particles back and forth, depositing in the particles the information the waves carry. That information can then be amplified and fed into a loudspeaker or on to a TV screen for humans to comprehend. Gravitational waves, according to Einstein, consist of an oscillatory space warp: an oscillating stretch and squeeze of space. In 1972 Rainer (Rai) Weiss at the Massachusetts Institute of Technology had invented a gravitational-wave detector, in which mirrors hanging inside the corner and ends of an L-shaped vacuum pipe are pushed apart along one leg of the L by the stretch of space, and pushed together along the other leg by the squeeze of space. Rai proposed using laser beams to measure the oscillating pattern of this stretch and squeeze. The laser light could extract a gravitational wave’s information, and the signal could then be amplified and fed into a computer for human comprehension. The study of the universe with electromagnetic telescopes (electromagnetic astronomy) was initiated by Galileo, when he built a small optical telescope, pointed it at Jupiter and discovered Jupiter’s four largest moons. During the 400 years since then, electromagnetic astronomy has completely revolutionised our understanding of the universe.

Radiation from the Big Bang may give us a clue to dark matter and dark energy. First of all, the echo, or afterglow, of the Big Bang is easy to detect. Our satellites have been able to detect this radiation to enormous accuracy. Photographs of this microwave background radiation show that it is remarkably smooth, with tiny ripples appearing on its surface. These ripples, in turn, represent tiny quantum fluctuations that existed at the instant of the Big Bang that were then magnified by the explosion. What is controversial, however, is that there appear to be irregularities, or blotches, in the background radiation that we cannot explain. There is some speculation that these strange blotches are the remnants of collisions with other universes. In particular, the CMB (cosmic microwave background) cold spot is an unusually cool mark on the otherwise uniform background radiation that some physicists have speculated might be the remnants of some type of connection or collision between our universe and a parallel universe at the beginning of time. If these strange markings represent our universe interacting with parallel universes, then the multiverse theory might become more plausible to skeptics. Already, there are plans to put detectors in space that can refine all these calculations, using space-based gravity wave detectors. LISA Back in 1916, Einstein showed that gravity could travel in waves. Like throwing a stone in a pond and witnessing the concentric, expanding rings it creates, Einstein predicted that swells of gravity would travel at the speed of light. Unfortunately, these would be so faint that he did not think we would find them anytime soon. He was right. It took until 2016, one hundred years after his original prediction, before gravity waves were observed. Signals from two black holes that collided in space about a billion years ago were captured by huge detectors. These detectors, built in Louisiana and Washington State, each occupy several square miles of real estate. They resemble a large L, with laser beams traveling down each leg of the L. When the two beams meet at the center, they create an interference pattern that is so sensitive to vibrations that they could detect this collision. For their pioneering work, three physicists, Rainer Weiss, Kip S. Thorne, and Barry C. Barish, won the Nobel Prize in 2017. For even greater sensitivity, there are plans to send gravity wave detectors into outer space. The project, known as the laser interferometry space antenna (LISA), might be able to pick up vibrations from the instant of the Big Bang itself. One version of the LISA consists of three separate satellites in space, each connected to the others by a network of laser beams. The triangle is about a million miles on each side.

I cofounded the LIGO Project in 1983 (together with Rainer Weiss at MIT and Ronald Drever at Caltech). I formulated LIGO’s scientific vision, and I spent two decades working hard to help make it a reality. And LIGO today is nearing maturity, with the first detection of gravitational waves expected in this decade.