题目内容
In practice, what often happens is that a new theory is devised that is really an extension of the previous theory. For example, very accurate observations of the planet Mercury revealed a small difference between its motion and the predictions of Newton's theory of gravity. Einstein's general theory of relativity predicted a slightly different motion from Newton's theory. The fact that Einstein's predictions matched what was seen, while Newton's did not, was one of the crucial confirmations of the new theory. However, we still use Newton's theory for all practical purposes because the difference between its predictions and those of general relativity is very small in the situations that we normally deal with. (Newton's theory also. has the great advantage that it is much simpler to work with than Einstein's ! )
It turns out to be very difficult to devise a theory to describe the universe all in one go. Instead, we break the problem up into bits and invent a number of partial theories. Each of these partial theories describes and predicts a certain limited class of observations, neglecting the effects of other quantities, or representing them by simple sets of numbers. It may be that this approach is completely wrong. If everything in the universe depends on everything else in a fundamental way, it might be impossible to get close to a full solution by investigating parts of the problem in isolation. Nevertheless, it is certainly the way that we have made progress in the past. The classic example again is the Newtonian theory of gravity, which tells us that the gravitational force between two bodies depends only on one number associated with each body, its mass, but is otherwise independent of what the bodies are made of. Thus one does not need to have a theory of the structure and constitution of the sun and the planets in order to calculate their orbits:
Today scientists describe the universe in terms of two basic partial theories-the general theory of relativity and quantum mechanics. They are the great intellectual achievements of the first half of this century. Unfortunately, however, these two theories are known to be inconsistent with each other-they cannot both be correct. One of the major endeavours in physics today, is the search for a new theory that will incorporate them both-a quantum theory of gravity. We do not yet have such a theory, and we may still be long way from having one, but we do already know many of the properties that it must have.
According to the passage, why can't any physical theory be permanently established？
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One summer night, on my way home from work I decided to see a movie. I knew the theatre would be air-conditioned and I couldn't face my【C1】______apartment.
Sitting in the theatre I had to look through the【C2】______between the two tall heads in front of me. I had to keep changing the【C3】______every time she leaned over to talk to him,【C4】______he leaned over to kiss her. Why do Americans display such【C5】______in a public place？
I thought the movie would be good for my English, but【C6】______it turned out, it was an Italian movie.【C7】______about an hour I decided to give up on the movie and 74 on my popcorn. I've never understood why they give you so much popcorn! It tasted pretty good,【C9】______. After a while I heard【C10】______more of the romantic-sounding Italians. I just heard the【C11】______of the popcorn crunching(咀嚼)between my teeth. My thought stated to【C12】______. I remembered when I was is South Korea(韩国), I【C13】______to watch Kojak on TV frequently. He spoke perfect Korean--I was really amazed. He seemed like a good friend to me,【C14】______I saw him again in New York speaking【C15】______English instead of perfect Korean. He didn't even have a Korean accent and I【C16】______like I had been betrayed.
When our family moved to the United States six years ago, none of us spoke any English.
【C17】______we had begun to learn a few words, my mother suggested that we all should speak English at home. Everyone agreed, but our house became very【C18】______and we all seemed to avoid each other. We sat at the dinner table in silence, preferring that to【C19】______in a difficult language. Mother tried to say something in English but it【C20】______out all wrong and we all burst into laughter and decided to forget it! We've been speaking Korean at home ever since.
【C1】
Why may partial theories be completely wrong？
Talking？
What in the world, muses Harold, do they have to talk about？
Betty shrugs. Talk？ We're friends.
Researching this matter called friendship, psychologist Lillian Rubin spent two years interviewing more than two hundred women and men. Like Betty and Harold, some were married, others single. They covered the gamut of what is chronologically called adulthood, twenty-five to fifty-five. They were blue collar, blue-blooded, and in between.
No matter their age, their occupation, their sex, their marital status, Rubin found the results were "unequivocal". Women have more friendships than men, and the difference in the content and the quality of those friendships is "marked and unmistakable".
More than two-thirds of the single men Rubin interviewed could not name a best friend. Those who could were 'likely to name a woman. Yet three-quarters of the single women had no, problem citing best friend, and almost always it was a woman. More married men than women cited a spouse as a best friend, most trusted confidant, or the one they would turn to in times of emotional distress. But even when a married woman named her husband to one of these categories, it was never exclusively his. "Most women," said Rubin, "identified at least one, usually more, trusted friends to whom they could turn in a troubled moment, and they spoke openly and ardently about the importance of these relationships in their lives."
In general, writes Rubin in her new book Intimate Strangers, "women's friendships with each other rest on shared intimacies, self-revelation, nurturance, and support." By contrast, "men's relationships are marked by shared activities." For the most part, Rubin contends, interactions between men "are emotionally contained and controlled-a good fit with the social requirements of manly behaviour."
"Even when a man claimed a best friend," Rubin wrote, "the two shared little about the interior of their lives and feelings." Whereas a woman's closest female friend might be the first to urge her to leave a failing marriage, "it wasn't unusual," Rubin discovered, "to hear a man say he didn't know his friend's marriage was in serious trouble until he appeared one night asking if he could sleep on the couch."
Women have more friends than men do,______.
For Phillip "P. J." Stambaugh, the glamour and gold of the dotcom boom swept him from Ithaca, N.Y. to California's Silicon Valley in 1999. And when Trishna Shah selected a job at an e-commerce strategy group after graduating from college last year, it was part of a carefully planned path to "success".
Both were beneficiaries of the technology boom of the late 1990s, and both are now among its victims. Yet for many, losing a job is proving more of a beginning than an end.
Painful and frightening as the process may be, individuals caught in the dotcom downdraft say they are making fundamental changes-the kind that could, in total, alter the outlook and values of many in their generation.
One thing is already certain. The character portrait of the dotcom generation, spoiled, self-centered, and unacquainted with the real world, is rapidly disappearing. In its place, a culture is emerging that puts greater emphasis on growth and opportunity at work, and less on salary and stock options. And for many, there is a deeper questioning of the meaning of life and career, say career guidance experts.
This is a far cry from the work-is-everything, sleep under-the desk, never-log-off, get-it-while-you-can mentality that has permeated the Internet culture.
Ms. Shah graduated from University of California Berkeley's business school last year and found a waiting court of recruiters. She selected work at an e-commerce strategy group, and the pieces were all fitting together. But when Shah was laid off earlier this year, "it was a real wake-up call," she says. "In college you're constantly planning for the next phase of life, your job and your career, "she explains. "But now I'm feeling different. I'm not living just for the next step."
At about the same time Mr. Stambaugh was still thriving at his job in Redwood City. He worked in business-development department of a start up that created Internet map technology.
But that wasn't what he had in mind when he entered Cornell University and successfully pursued a degree in landscape architecture, a field that connected with his love of the outdoors and plants. After graduation in 1999, though, Stambaugh headed to Silicon Valley, persuaded by friends who were quickly landing jobs and making good money. But by last fall, Stambaugh was sending pained e-mails to his sister back east. In one, he complained that his work to create better and better Internet products had become "absent of the things I value."
The economy, in a sense, put an end to his disillusionment, forcing his dotcom out of business a few months ago.
These days, Stambaugh has less money, but an out door tan and high spirits. He is project manager for a landscape firm, spending most of his day meeting with customers and discussing their gardening and landscape dreams. "I'm a different individual now," he says. "I'm happy on a real high level."
Of course there are many still employed in the Internet world, and loving it. But even among the employed, there is a new uncertainty. The unemployment rate in Santa Clara Country for April jumped sharply, a reminder that the flow of pink slips could continue to accelerate.
Even for many of those who continue to work in technology, attitudes seem different. Says Mr. Epperheimer: "The pendulum has moved back to a more balanced approach to work and life."
The experience of Ms. Shah and Mr. Stambaugh is described mainly to show that______.
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