The announcement of the LIGO and VIRGO collaborations on the direct detection of gravitational waves confirms one of the main predictions of Einstein Einsteins, almost a hundred years after its realization. For hundreds of LIGO scientists, this new discovery of gravitational waves not only marks the culmination of decades of research, but also the beginning of a new way of looking at the universe. Detecting and analyzing information carried by gravitational waves allows us to observe the universe in ways never before seen, allowing astronomers and other scientists to see literally unseen wonders for the first time.
Gravitational waves can be detected indirectly by observing celestial phenomena caused by gravitational waves, or more directly using instruments such as ground-based LIGO or the planned space-based LISA instrument. In the decades after gravitational waves were predicted, direct observation of gravitational waves was impossible because tiny effects had to be detected and isolated from the vibrational background everywhere on Earth. It wasn’t until 2015 that the LIGO scientific collaboration directly detected gravitational waves using a pair of ultrasensitive detectors. In the 1970s, Einstein first explored dual LIGO interferometers as a means of detecting gravitational waves.
The researchers detected the signal using the Laser Interferometer Gravitational-Wave Observatory (LIGO), a double detector carefully constructed to detect the extremely tiny vibrations from passing gravitational waves. Gravitational waves were first detected indirectly in the 1970s when scientists observed a pair of pulsars orbiting each other. They concluded that a pair of neutron stars orbiting each other in such a way that they must lose energy in the form of gravitational waves, a discovery that earned the researchers the 1993 Nobel Prize in Physics. In this case, researchers at MIT and Caltech played a leading role — they observed the ripples of gravitational waves directly in their instruments on Earth.
Physicists first detected these waves using a laser detector in 2015, and other scientists tracked them with ground-based radio telescopes. Recently, researchers have created tools that allow them to study the universe using X-rays, radio waves, ultraviolet and gamma rays. Data from the Fermi Gamma-ray Space Telescope could theoretically also detect transmitted waves, a new study shows. A passing gravitational wave will slightly alter the distance between the pulsar and Earth, tracking the arrival times of pulses from a group of pulsars in the Milky Way over many years, known as the pulsar time matrix (PTA), astronomers hope. Detections indicate tiny changes in the passage of gravitational waves.
While LIGO directly measures tiny changes in the distance between two mirrors that are several kilometers apart, it cannot directly measure changes in the distance between Earth and the pulsar, in part because thousands of gravitational wave peaks and valleys travel between them. IPTA’s collaborative pulsar technology looks for intense gravitational waves as they travel through the Milky Way, stretching and compressing the space that separates our solar system from rotating neutron stars called pulsars (see pulsars as detectors). The gravitational waves detected by LIGO are caused by some of the most energetic events in the universe: the collision of black holes, the merger of neutron stars, the explosion of stars, and possibly even the birth of the universe – the universe. According to the researchers’ calculations, the gravitational signal is the result of the collision of two massive black holes 1.3 billion light-years away, an extremely extreme event that has yet to be observed.
The waveforms detected by two LIGO observers [6] are consistent with the predictions of general relativity [7] [8] [9] for gravitational waves emanating from the inner spiral and for a pair of black hole mergers of approximately 36 and 29 solar masses and subsequent A single black hole produced by the “ringing”. The collision detected by LIGO occurred before the instrument even began its first official post-enhancement observations, but it may have been a lucky twist. First, the discovery of two black holes is exciting in itself: No one knows for sure whether the black holes actually merged together to form the more massive black hole, but now there is physical evidence. Last year, using data collected over a decade, the PTA team in North America and Europe announced that they had collected a weak statistical signal, hinting at something called the gravitational wave background — which reflects all the merge. The universe, known as the background of gravitational waves, is the echo of the merger of all the supermassive black holes in the universe.
Five years ago, the Laser Interferometric Gravitational Wave Observatory (LIGO) detected ripples in spacetime that were only one ten-thousandth the width of a proton—a technical feat equivalent to accurately determining the distance to a star closest to three-thousandths. centimeters. Yesterday morning (February 11), people around the world rejoiced when scientists announced the first direct detection of gravitational waves – ripples in the fabric of space-time, the existence of which was first proposed by Albert Einstein, in 1916 gravitational waves – ripples in the fabric of space-time. whose existence was first proposed by Albert Einstein in 1916. Since the coupling of gravitational forces to masses is inherently much weaker than the coupling of electromagnetic forces to charges, the generation and detection of gravitational radiation is much more difficult than electromagnetic radiation. However, in Scottish physicist James Clerk Maxwell’s theory of electromagnetism, accelerated charges radiate signals (electromagnetic radiation) moving at the speed of light, while in Newton’s theory of gravity, accelerated masses transmit information (action at a distance) that travels at infinite speed. .