4/18/2023 0 Comments Black desert into the waves![]() ![]() For this, they received the Nobel Prize in physics in 1978. Penzias and Wilson had discovered the echo from the Big Bang by accident, today known as the “cosmic microwave background”, or CMB for short. Except the residual radiation from the Big Bang, now cooled from an original temperature of 3000K to 3K. However, this all changed when two scientists at Bell Laboratories, Arnos Penzias and Robert Wilson, accidentally made the discovery of a lifetime: While they were trying to make a picture of the Milky Way using a new radio antenna, they found an unexpected “noise term” in their observations of 3 degrees Kelvin.Īnd this signal had one very peculiar property: It was equally strong in all directions on the sky. ![]() Until 1965, the Big Bang theory was mostly a theoretical speculation, based on mathematics rather than hard observations. The cosmic microwave background and two Nobel prizes This idea is today known as “the Big Bang”. Taking this idea to its extreme, Einstein’s theory therefore makes the following simple prediction: The universe started as an extremely hot and dense gas, in which only the very simplest elementary particles could exist anything heavier than photons, protons and electrons would be instantly destroyed by the extreme heat. And when the density increases, so does the temperature. And that means that the density of the universe must have been higher in the past. And this has a very interesting and simple consequence: If the universe expands today, then it must have been smaller in the past. ![]() The same happens in the universe all galaxies move away from each other. This effect can be compared to the surface of an inflating balloon as the balloon inflates its surface area becomes larger and larger, and the distance between any two points on the surface increases. The second important prediction is that the universe as a whole expands, as was later observed directly by Edwin Hubble in 1929. However, the physical magnitude of such variations is typically very small indeed: The waves produced by the Earth orbiting the Sun correspond to a stretching of space by only one part in 10 26! For this reason, no gravitational waves have been directly observed as of 2011. Such waves arise whenever strong gravitational sources accelerates, say, when two black holes orbit each other. First, according to Einstein the gravitational field set up by a massive body should behave in a similar way as the electromagnetic field: Disturbances in this field should move at the speed of light, just like photons, forming what is called gravitational waves. ![]() For QUIET, two are of particular interest. In a spectacular media display, Eddington confirmed Einstein’s predictions, and Einstein rose to instant world fame.Įinstein’s theory made many other predictions as well. The first opportunity to do so came in 1919, when British astronomer Lord Eddington measured the bending of light around the Sun during a total solar eclipse: According to Einstein’s theory the amount of bending would be twice as large as predicted by Newton’s theory. This idea can be illustrated by a pilot flying around the world: Locally, the pilot always attempts to fly in the straightest possible line, and yet, after some 36 hours he comes back to the point where he started his flight, because the Earth is spherical.Īs with any great scientific theory, this idea could be tested by observations. While Newton believed that gravity was a somewhat mysterious force that pulled bodies together through large distances, Einstein claimed that gravity was nothing but the manifestation of a curved spacetime, and any body simply attempts to move in the straightest possible line within this curved space. On this date, Albert Einstein submitted a paper called “The field equations of gravitation” to the Prussian science academy, which provides a fundamentally new understanding of gravity. The background for the QUIET experiment begins almost 100 years ago, on November 25th 1915, to be precise. Albert Einstein, gravity waves and the biggest bang of them all Right in the middle of this race are the University of Oslo and NOTUR, whose computational expertise and resources have enabled Norwegian scientists to take on leading roles in the experiment. This experiment is called the “ Q/U Imaging ExperimenT” (“QUIET” for short), and is one of several experiments competing to become the first to detect the tiny signal. ![]()
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