Published 2015-08-29 17:28
Stephen Hawking lecture in Stockholm.
The world-famous physicist Stephen Hawking has just visited Stockholm and presented an idea for a solution to a 40-year-old paradox about black holes. Next week the astronomer Bengt Gustafson’s book on how our knowledge of the remarkable black holes have evolved since the first theories in the 1700s.
The world-famous physicist Stephen Hawking has just visited Stockholm and presented an idea for a solution to a 40-year-old paradox about black holes. Next week the astronomer Bengt Gustafson’s book on how our knowledge of the remarkable black holes have evolved since the first theories in the 1700s.
– If you feel that you are stuck in a black hole. Do not give up. There is a way out.
Stephen Hawking ending to the lecture at the Stockholm Waterfront Congress Center on Monday night was greeted by a standing ovation from the 3,000 audience in the packed courtroom.
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– It is true that reality can surpass the poem. Black holes are more remarkable than any science fiction writer could find, he initiated delivered an hour earlier.
The 73 years old man completely paralyzed physicist has gained an almost mythical status: the genius who is locked in his own body. The lecture, which he delivered with the help of a computer, which he controls with his cheek, was all right for black holes: their strange characteristics, what we know about them and what we do not know.
The biggest mystery is where the information about everything that falls into the hole goes.
– I have now discovered how the information is preserved, said Stephen Hawking, and promised to present his theory at a seminar at the Royal Institute of Technology KTH, the following day.
A black hole is so heavy and so strong pull that not even light can leave it. Everything passing hole boundary – the event horizon – will fall down in a bottomless pit and never return. Stephen Hawking compares it with the canoe at Niagara Falls. As long as you are above the waterfall, you have a chance to meet you, only you are strong enough in the arms and have the energy to paddle against the current.
– But as soon as you get over the edge you are lost, says Stephen Hawking .
In the mid-1970s he discovered that the holes are still not completely black. They give off a very low heat radiation and will eventually evaporate. But then also disappears information about everything that has been sucked into the hole. It goes against quantum mechanics, which states that information can not be destroyed.
– I spent much time and effort to get rid of this embarrassing effect, says Stephen Hawking.
Since then , physicists have tried to resolve the information paradox and find out what happens when the universe’s black holes evaporate and disappear. The number of years until it takes is a one with 70 zeros after or more.
– One of the biggest problems in physics is therefore about what happens in a so-distant future. Tell ahead, says Bengt Gustafsson, Professor Emeritus of Astronomy at Uppsala University.
Bengt Gustafsson. Photo: Sigbritt Ernald
The problem is one collision of physics two basic theories: quantum mechanics, which describes the smallest components, and the general theory of relativity, which deals with gravity, development of the universe and the planets, stars and galaxies move.
– New physics always sets things to a head. The clearest example is from the period around the turn of the century, when it became a direct contradiction between Newtonian mechanics and the man knew about electromagnetism. It led eventually to Einstein’s special theory of relativity, says Bengt Gustafsson.
According to general relativity, a black hole just three properties: mass, rotation and electric charge. So there is no way of knowing if that had fallen into the hole was a bus or a sewing machine, or even if it was a matter or antimatter. The major problems of quantum mechanics ban on destroying information.
Physicists have taken different routes in trying to resolve the paradox. Some want to preserve the general theory of relativity, the second quantum mechanics, and there are solutions that use the so-called string theory.
– My suggestion is that the information is not stored inside the black hole, but on the horizon, said Stephen Hawking at the seminar KTH Tuesday.
Stephen Hawking. Photo: Anna-Lena Wejderman
The idea, he developed with Malcolm Perry at Cambridge University and Andrew Strominger at Harwarduniversitetet in the United States, and it builds on theories from the beginning of the 1960s. The three physicists believe everything disappears into the black hole, leaving the four-dimensional mark in the so-called space-time – a way of looking at space, with time as the fourth dimension – around. The information is retained, but in a very esoteric form.
– It’s like firing up an encyclopedia. Everything is left in ashes, but it is difficult to read, says Stephen Hawking.
He and his colleagues call the imprints of gravitational charges. They let the black holes an additional feature. Stephen Hawking joins thus now the scientists who want to preserve quantum mechanics and modify general relativity.
Bengt Gustafsson very fascinated by the research on these strange objects in the universe. Next week his book “Black Holes”, which describes how the theories of them have evolved over more than 200 years.
Founded in 1783 wrote the English clergyman John Michell in an article about dark stars, which were so large and heavy to light can not manage this, and suggested that there could be many such in the universe.
Since physicists discovered that light was a wave, and thought that it could be affected by gravity. The ideas about dark stars were therefore buried up until Albert Einstein formulated the theory of relativity. But it was not until around 1960 that black holes won great support among scientists.
The American physicist John Wheeler usually considered to be the one who coined the name black holes, but the book shows Bengt Gustafsson it was another American, Robert Dicke, who is the real author. He took the name from a terrible prison, the black hole of Calcutta, a four times five meters large cell in which 146 British soldiers were detained one night in June 1756. Almost all choked to death.
– You can think how the prisoners there reached up to the little window, just like the light that tries to come out of the black hole without success, says Bengt Gustafsson.
Now, physicists view Stephen Hawking’s suggestions and check how much it is where. Bengt Gustafsson is doubtful how played out against the media and the general public gaining influence over research.
– We have seen a number of physics event where researchers have gone around the traditional audit and presented new half-baked results in great excitement, said he said.
Stephen Hawking shown the path he has chosen. The future will tell whether it was right.
– I think we will have to live with this issue for some time to come, says Bengt Gustafsson.
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