After almost 30 years of arguing that a black hole swallows up everything that falls into it, British astrophysicist (天體物理學家) Stephen Hawking moved backward last week.
The world-famous writer of "Brief History of Time" said he and other scientists had got it wrong. "I've been thinking about this problem for the last 30 years, and I think I now have the answer to it," said Hawking. "A black hole only appears to form but later opens up and set free information about what fell inside. So we can be sure of the past and can predict the future." The findings could help solve the "black hole information paradox(似是而非的觀點)", an important puzzle in modern physics.
A black hole is an area in space where matter is under such pressure that even light can not escape from its gravitational pull(引力). But, exactly what happens there has long puzzled scientists.
Black holes occur when a powerful star burns up its nuclear fuel and gravity forces it to break down in on itself. The great weight of the star's outer layers moves in towards its center. The force of gravity keeps nearly all light from escaping and nothing inside can be seen from the outside. The star actually disappears from the universe into a point of infinite density(高密度). That is a place where the laws of general relativity that govern space and time break down.
Hawking has devoted most of his life to studying these questions.
At the beginning, cosmologists believed the holes were like a "universal vacuum (真空) cleaner", sucking up everything in their path.
Hawking revolutionized the study of black holes when he proved, in 1976 that, under the strange rules of quantum physics(量子物理), when black holes form they send out energy and lose mass in the process.
In thinking up this so-called "Hawking radiation", the
These particles (粒子), he said, contained no information about what has been occurring inside the black hole, or how it formed. Under his theory, once the black hole disappears, all the information within it is lost.
72. What's the importance of Hawking's new findings?
A. They could help solve the puzzle about black holes.
B. They has solved the mystery of "black holes".
C. We can now know what is going on inside "black holes".
D. Scientists have already predicted the future of "black holes" now.
73. What's the meaning of the underlined word "cosmologist" (in Paragraph 9)?
A. A person who studies the universe and its origin and development.
B. A person who studies the stars and their development.
C. A person who travels in a spacecraft.]
D. A person who studies the position of the stars and the movements of the planets.
74. Which of the following is TRUE?
A. Hawking has now studied black holes for more than 40 years.
B. During the course of the black hole's forming the enormous weight of the star's center moves into the outer layers.
C. Almost nothing can escape from the gravitational pull of the black hole.
D. Scientists have been thinking the black hole contains no information.
75. What would be the best title for the passage?
A. The Formation of the Black Hole B. Black Hole Information Paradox
C. Black Hole Mystery D. The Cause of the Black Hole
科目:高中英語 來源:同步題 題型:完形填空
完形填空。 | |||
When I come across a good article in reading newspapers. I often want to cut and keep it. But just as I am about to do so I find the article on the 1 side is as much interesting. It may be a discussion of the way to 2 in good health, or a 3 about how to behave and conduct oneself in society. If I cut the front article, the opposite one is likely to 4 damage, leaving out half of it or keeping the text 5 the title. Therefore, the scissors would 6 before they start, 7 halfway done when I find out the 8 result. Sometimes two things are to be done at the same time, both worth you 9 .You can only take up one of them, the other has to wait or be 10 up. But you know the future is unpredictable (不可預料) - the changed situation may not allow you to do what is left 11 . Thus you are 12 in a difficult position and feel sad. How 13 that nice chances and brilliant ideas should gather around all at once? It may happen that your life 14 greatly on you preference of one choice to the other. In fact that is what 15 is like, we are often 16 with the two opposite sides of a thing which are both desirable like a newspaper cutting. It often occurs that our attention is drawn to one thing only 17 we get into another. The 18 may be more important than the latter and give rise to a divided mind. I 19 remember a philosopher's remarks, "When one door shuts, another opens in life." So a casual (不經(jīng)意) 20 may not be a bad one. | |||
( )1. A. front ( )2. A. get ( )3. A. advice ( )4. A. suffer ( )5. A. on ( )6. A. use ( )7. A. or ( )8. A. satisfying ( )9. A. courage ( )10. A. given ( )11. A. near ( )12. A. filled ( )13. A. dares ( )14. A. improves ( )15. A. study ( )16. A. faced ( )17. A. before ( )18. A. following ( )19. A. still ( )20. A. treatment |
B. same B. keep B. news B. reduce B. for B. handle B. but B. regretful B. strength B. held B. alone B. attracted B. comes B. changes B. society B. supplied B. after B. next B. also B. action |
C. either C. lead C. theory C. prevent C. without C. prepare C. so C. surprising C. attention C. made C. about C. caught C. deals C. progresses C. nature C. connected C. until C. above C. once C. choice |
D. opposite D. bring D. report D. cause D. off D. stay D. for D. impossible D. patience D. picked D. behind D. struck D. does D. goes D. life D. fixed D. as D. former D. almo st D. remark |
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