On the morning of June 19, the International Conference on String Theory opened in the Great Hall of the People in Beijing. Thousands of participants once again gave Hawking the warmest applause.
"Why are we here? Where did we come from? " Hawking's report entitled "The Origin of the Universe" has two questions at the beginning and the end, which bring people's thoughts into deep time and space. During the 40-minute speech, many listeners shared the same breath and thought with Hawking.
Time, space, superstrings, black holes ... Although not everyone can understand these abstruse concepts and theories, most people are listening carefully. Under the big screen displaying Chinese, dozens of young students stood from beginning to end, listening attentively and staring at the screen, quickly catching and catching up with the master of science's thoughts.
"There are many Hawking fans around me. Everyone wants to see Hawking, but the tickets are too tight. "
"He is a disabled person and a great person, which makes people respect him."
"Although I don't quite understand his theory, the magical universe he described embarrassed me."
"Hawking is an outstanding scientist. He has made important contributions in mathematics and physics. " Qiu Chengtong, the chairman of the conference and a famous mathematician, pointed out that there were also authoritative experts such as Professor Gross, founder of quantum chromodynamics, and Professor Witten, a famous theoretical physicist. "Their innovative spirit is worth learning."
"If we do find a complete theory, it should be understood by everyone in time in general principle." Hawking is practicing the promise in A Brief History of Time with his own actions-he works hard in the garden of science with his own efforts, and also uses his own strength to promote the public's understanding of science and spread new scientific knowledge and spirit.
Hawking once predicted that China would lead the world in science and technology in the future. The resurgence of Hawking fever makes people call for bold practice and innovation, and strive to be the vanguard in the process of building an innovative country. Li Bin Wu Jingjing
Character background
Roaming the universe in a wheelchair
Hawking's fame began with his study of black holes. After combining general relativity with quantum theory, Hawking published a paper in Nature in March 1, 65438 and 974, expounding his new discovery that black holes are radioactive.
This discovery is regarded as the most important progress in the field of theoretical physics for many years, and his paper is also called "one of the most profound papers in the history of physics".
Starting from the study of black holes, Hawking continued to explore the origin and destination of the universe, answering the questions that human beings have been exploring: Does time have a beginning and does space have a boundary? 1983, Hawking published his own research conclusion: the universe is finite, but there is no edge. Just as the earth's surface is limited but no edge can be found, time has a beginning, which began about1500-20 billion years ago.
1988, Hawking's masterpiece A Brief History of Time: From the Big Bang to the Black Hole came out. This book is regarded as a landmark masterpiece in the history of human science. By the end of 1995, 10, the circulation of this book has exceeded 25 million copies and it has been translated into dozens of languages.
In 200 1 year, Hawking completed the companion piece "The Universe in the Shell" of A Brief History of Time. Hawking also co-authored and published Large-scale Structure of Space-time (1973), Review of General Relativity: Commemorating Einstein's Centennial Birthday (1979), Hyperspace and Supergravity (198 1) and The Beginning of the Universe.
Hawking's legend also stems from his extraordinary life experience. Hawking was diagnosed with amyotrophic lateral sclerosis (ALS) as early as the later period of his college studies, and soon became paraplegic. From 65438 to 0985, Hawking lost his language ability, and the only tool to express his thoughts was a computer speech synthesizer. He used a few movable fingers to operate a special mouse to select letters and words on the computer screen to make sentences, and then played the sound through the computer. It usually takes five or six minutes to make a sentence, and it takes 1 hour to prepare a recorded speech. Despite this, Hawking is still keen on public speaking, willing to exchange ideas with others and spread scientific ideas around the world.
Hawking 1942 1.8 was born in Oxford, England. He studied at Oxford University and Trinity College of Cambridge University successively, and obtained a doctorate in physics from Cambridge University.
From 65438 to 0965, Hawking entered gonville and Caius College of Cambridge University as a researcher. During this period, he founded the famous theory that the beginning of the universe is "a point of infinite density" on the study of the origin of the universe. From 65438 to 0969, Hawking began to be an outstanding achievement researcher in gonville Academy of Sciences and Caius University.
1972- 1975, Hawking worked in the Institute of Astronomy and the Department of Applied Mathematics and Theoretical Physics of Cambridge University. 1975- 1977 Senior Lecturer in Gravity Physics; /professor kloc-0/977-1979. Since 1979, Hawking has served as Lucas Professor of Mathematics, a position that once belonged to the great scientist Newton.
Hawking, 64, has won many honors and awards. 1974 was elected as the youngest member of the Royal Society, and 1974- 1975 became a meritorious scholar of the fairchild Lecture of California Institute of Technology. 1978, Hawking won the Albert Einstein Prize, the highest prize in theoretical physics research in the world. 1988 won the Wolf Prize in Physics.
From 65438 to 0990, Hawking divorced his wife Jane Wilde, who had been married for 25 years. He and Wilder have three children. Hawking married his nurse Elaine Mei Sen on 1995.
Chronology of Stephen Hawking's events
1942 65438+1October 8th, born in Oxford, England.
1963, diagnosed as amyotrophic lateral sclerosis.
1973, the first large-scale structure of time and space was published.
1974 discovered black hole radiation and became a member of the Royal Society.
1979, Review of General Relativity: Commemorating Einstein's Centennial Birthday was published.
198 1 published the boundless concept of hyperspace and supergravity.
1985, loss of language ability during tracheotomy, using a computer with a speech synthesizer.
1988 published A Brief History of Time: From BIGBANG to Black Hole, and won the Wolf Foundation Award.
1993 published papers on black holes and baby universes.
new thought
Hawking overthrew his black hole theory?
I'm sorry to disappoint you
On July 2 1 2004, at the 17th International Conference on General Relativity and Gravity (GR 17) held in Dublin, Ireland, Stephen Hawking announced to scientists and journalists gathered around the world that he had solved an important problem in physics: Did black holes destroy the information they swallowed?
At the meeting, Hawking gave a speech on his latest discovery. He announced that he had overthrown the famous black hole theory he established a few years ago, and revisited the problem of information conservation.
"This problem that has been bothering me for 30 years has finally been solved, which is great." Hawking said in his speech that he would further explain his new theory in his paper.
Black holes don't break the law of causality.
Stephen Hawking's speech caused an uproar in the whole physics field. Dr Robert Mann, head of the Department of Physics at the University of Waterloo in Canada, and 800 other physicists listened to Hawking's speech.
"After listening to his speech, almost no one can understand what he said. Probably only Hawking himself knows these things. " Robert Mann commented on this genius's speech. Reminiscent of the situation that "only three people in the world understand the theory of relativity".
Robert Mann tried to explain the differences of Hawking's theory in vivid and simple language.
"Forty years ago, people began to seriously think about black holes, and thought that the only information that outsiders (observers outside black holes) could get from black holes was mass, charge and angular momentum. This means that if you use any substance to make a black hole, such as crushed beer bottles, crushed stars or anything else, outsiders can't tell what is inside the black hole. "
"Hawking's theory 30 years ago believed that from the perspective of quantum mechanics, black holes can radiate (that is, the famous Hawking radiation). Due to the quantum effect, both beer black hole matter and stellar black hole matter began to radiate and began to transpiration. The problem is that Hawking's initial calculation shows that transpiration is completely a thermal effect, that is, it should not contain any information, that is, there is no difference between the radiation of beer black hole matter and stellar black hole matter. Therefore, when the black hole becomes smaller and smaller and finally evaporates to nothing, it means that all information has been lost. In addition, it is impossible to recover this information at the end of the change. "
This theory has been in trouble since its birth: it contradicts the "law of information conservation" that many scientists insist on, and was once called "black hole paradox".
Just as scientists in the19th century put forward the law of conservation of energy, many scientists in the 20th century put forward the theory of conservation of information. If this statement is true, the law of conservation of information will undoubtedly become the most important law in the scientific community, perhaps more profound than the laws of conservation of matter and energy. Hawking's black hole theory has caused a heated debate about whether information can be preserved and conserved in black holes.
Robert Mann said that most physicists believe that no information can be destroyed, otherwise it would violate the law of causality. "Because we are convinced of causality, the job of physics is to predict the future through the past under initial conditions." This means that if information is destroyed-as Hawking said in his theory 30 years ago, the future cannot be predicted by information at all.
For 30 years, Hawking insisted that the "Law of Conservation of Information" failed in black holes. "In a black hole, information will really be lost. If it is lost, it will enter another space, which is called baby universes. As the name implies, baby universes comes from our universe. " .
But 30 years later, Hawking announced that he had proved a new answer by Euclid's mathematical method of path integral-the information was not destroyed after entering the black hole. "if you enter a black hole, the matter and energy you carry will return to our universe ... it has been torn off, but it contains all your information, but it is no longer easy for us to recognize."
"Sorry, I lost my hope in science fiction." Hawking said this in his speech.
Hawking is willing to gamble and lose.
For Hawking's announcement that his original black hole theory "suddenly died", his colleague Gary Gibbons at Cambridge University thinks that this incident really surprised physicists. You know Hawking's learning style is quite dramatic. He will put forward a theory and stick to it until it is overthrown by other better arguments.
If Hawking abandons his original black hole theory, he will lose a gamble. This is a rather interesting story.
From 65438 to 0997, Hawking and two scientists from California Institute of Technology, Chip Thorne and John Prischi, made bets on their respective theories. Hawking and Chip Thorne believe that black holes will capture information and never release it. John Prischi believes that black holes have some unknown sieve holes, through which information will be safely evacuated from black holes. The winner will get a set of encyclopedias of his choice.
Professor Prischi introduced the gambling game and the profound theory behind it in vivid language on his personal website: "Hawking's original theory of black hole evaporation-disappearance is an amazing insight, and many people in theoretical physics didn't fully realize the depth of Hawking's question until many years later. His theory once triggered a real crisis in the field of basic physics, which made us seem to have to give up at least one of our cherished beliefs. To this end, Hawking also put forward radical suggestions that the foundation of quantum theory needs to be revised. "
However, at the venue in Dublin, Hawking made concessions in this gamble.
Prischi was not excited about winning the bet. "Stephen's change of mind surprised me. Why is this new idea so powerful that he is willing to overturn his position that he has adhered to for nearly 30 years? For me, it is not clear why. "
Prischi said that it even made him a little sad: in the past few years, Stephen and he had a lot of discussions about the mystery of black hole information, and he always enjoyed these discussions and learned something from them, even though they disagreed in the discussion.
"We are really standing in a position now. In the future, we may find other things that can be debated, but nothing is more profound and interesting than the information problem of black holes. "
However, Prischi was satisfied with the trophy he won: Hawking gave him an encyclopedia of baseball.
Just a mathematical conclusion?
Chip Thorne, who was originally on Hawking's side, refused to give up. "I need to see more narratives before I give in." But he added: "But I think Stephen's decision is basically correct."
Chip Thorne didn't want to give up right away for a simple reason: neither he nor his rival Prischi understood Hawking's new theory. If you give up now, you don't know where you lose.
Similarly, Prischi doesn't know why he won. Hawking said in his speech that his latest calculation shows that the horizon (that is, the surface of a black hole) is full of "quantum disturbances". This is just similar to the content elaborated by one of the core theories of quantum mechanics-the famous Heisenberg uncertainty principle-these quantum disturbances can gradually release the information absorbed by black holes. In this way, the knot of the original "black hole paradox" is naturally opened.
"I don't completely agree with his new point of view. I hope Hawking can provide details in the published paper that he failed to disclose in his speech. I strongly feel that even if Hawking's new method is widely accepted, it will leave a lingering problem, that is, how information escapes through a clear path. " Prischi said.
Some physicists attending GR 17 conference still support Hawking's earlier views, but it's a pity that he overthrew his own. Other physicists question whether Hawking has really solved the long-standing problem of "black hole paradox". "This still doesn't convince me." John friedmann, a physicist at the University of Wisconsin in the United States, questioned Hawking's mathematical method (Euclid path integral method) in an interview with the American magazine Science.
Theorists in the quantum field are sometimes willing to use this Euclidean path integration method to solve the problems of ions and fields. But this method sometimes meets the problem of infinite limit, which is why most gravity theorists try to avoid using this method. They prefer to choose some more direct mathematical methods, such as Lorentz function to calculate gravity problems. At present, no one can prove that these two methods can finally get the same calculation results.
Friedman said, otherwise, Hawking's conclusion can only be a mathematical answer at most, not a universal law.
Nevertheless, as Robert Mann said, whatever the final result, Hawking's new theory will not affect what you eat at noon today. But his new ideas will surely become another wonderful feast of human imagination. Fang Xuanchang Feng Yifei
hawking prophecy
Humans will live in space.
A few days ago, Hawking boldly predicted at a news conference that if human beings do not perish due to cannibalism in the next 100 years, they should emigrate to other planets and establish self-sufficient space colonies without the support of the earth.
Hawking said that he believes that global warming, nuclear war and genetic virus may one day completely destroy life on earth. If human beings want to live in the universe forever, they must explore their homes on other planets. Hawking believes that humans can establish a permanent base on the moon in about 20 years and reach Mars 40 years later. But both planets lack oxygen and are too small for human habitation.
Hawking said: "For the survival and continuation of mankind, we should live in space." This is very important. The danger of extinction of life on the earth is increasing, such as the sudden rise of the earth's temperature, nuclear war, genetically mutated viruses or other unexpected disasters. "Hawking said that human beings should have a space colony that does not need the support of the earth.
In recent years, due to outstanding problems such as social employment pressure, mental health problems of college students have occurred from time to