Black holes. They act like huge drains in the universe. Frightening Fascinating Or just fantasy The very concept of black holes confuses our common sense notions of matter, time, and space. The theory that black holes can, and probably do, exist in space doesn’ t only concern scientists and astronomers.
(61)For if the theory is valid, we must question all our basic physical laws and, indeed, our "normal" experience of the physical world around us.
What is a black hole Well, it’s difficult to answer this question, since the terms we would normally use to describe a scientific phenomenon are inadequate here. (62)Astronomers and scientists think that a black hole is a region of space (not a thing) into which matter has fallen and from which nothing can escape--not even light. So we can’ t see a black hole. A black hole exerts a strong gravitational pull and yet it has no matter. It is only space---or so we think. How can this
Black holes. They act like huge drains in the universe. Frightening Fascinating Or just fantasy The very concept of black holes confuses our common sense notions of matter, time, and space. The theory that black holes can, and probably do, exist in space doesn’ t only concern scientists and astronomers.
(61)For if the theory is valid, we must question all our basic physical laws and, indeed, our "normal" experience of the physical world around us.
What is a black hole Well, it’s difficult to answer this question, since the terms we would normally use to describe a scientific phenomenon are inadequate here. (62)Astronomers and scientists think that a black hole is a region of space (not a thing) into which matter has fallen and from which nothing can escape--not even light. So we can’ t see a black hole. A black hole exerts a strong gravitational pull and yet it has no matter. It is only space---or so we think. How can this
Like all the huge metropolises of the world, there are lots of diversions both outdoors and indoors in Chicago. The Art Institute of Chicago has one of the world’s (1) art collections, including more French Impressionist paintings than even in the Paris Louvre itself. The Field Museum of Natural History and the Museum of Science and Industry are also great historical and cultural treasure houses to (2) as well as entertain children and adults (3) In the Field Museum one comes (4) a surprisingly big collection of Chinese exhibits from the ancient (5) to the early century. The Sears Tower and the Buckingham Fountain are the pride of the Chicagoans; (6) having 110 storeys is said to be the highest tower in the world and the (7) is the largest fountain in the United States. Lake Michigan is for yachting in summer time, (8) the highlights of Chicago life all the year round are concerts, operas and plays (9) by the ci
A. the first
B. the former
C. the previous
D. the formal
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