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吐泄伤津，可见
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阅读短文，完成96—100题。 人们要找出自然的规律，不借助对称也很难。也许正是因为这样，自然才一次次地打破人们先前找到的对称。 这种现象在物理学中的表现很明显，大概是因为物理学是个很重视规律的科学吧。且不说完美的牛顿力学如何不能完好地解释自然，让我们看看粒子物理学中三个起支撑作用的对称：一个是正反粒子变换对称(简称C对称)，一个是空间(镜像)反射变换对称(简称P对称)，另一个是时间反演变换(把时间颠倒，将T变成—T)对称(简称T对称)。对称就是不变性，也叫守恒，这些守恒是粒子物理学的支柱。举个形象的例子，比如我们的两只手，把一只手放在镜子上，镜子里边的手就与我们另外一只手一样，这种经过镜像反射的现象叫宇称。这两只手的行为遵从同样的物理定律，就像两只手对拍与一只手对着镜子拍是一样，这就是宇称守恒。当你一只手对着镜子拍时，镜子里的手或者说你的另一只手却不跟着拍，宇称就不守恒了。没想到的是，自然界还真是这样的不听话。 首先打破的是P守恒，1956年，李政道和杨振宁在分析最轻的奇异粒子衰变遇到的“θ—τ疑难”的过程中，就遇到了这样的怪事。没办法只能改变思路，提出宇称(P)可能是不守恒的，在强相互作用和电磁相互作用下，P是守恒的，但在弱相互作用下未经过判定性检验。只有提出在弱相互作用过程中，宇称不守恒，才能解决“θ—τ疑难”。后来的实验果然证明宇称在弱相互作用下是不守恒的。为弥补这一缺陷(物理学家称之为破缺，比较形象，说明大网破开了一个角)，又提出CP联合变换是守恒的，这样也能保证物理规律的不变性。 补起来的网自然有更多的弱点，不久，人们在K介子的衰变中发现了CP守恒的破坏迹象。为了进一步验证这一现象，人们不惜斥巨资建立了“B介子工厂”，据说B介子的行为可以更好地判定CP的守恒与否。几年的实验已经证明，CP确实不守恒，支柱有些动摇了。 我们知道，强作用、电弱作用、引力作用，这三种作用的基础都是建立在对称的理论上的。可是实验不断发现对称不守恒，对现代物理不断造成冲击，使得破缺越来越大。与其说修补破网，有时可能不如重新编织一张新网来得更省事，就看能不能找到另外的对称了。 由此看来，不对称是合理的，可能比对称更合乎自然。用句哲学上的话来说，对称是相对的，不对称是绝对的。不对称才让科学有事可做。 人们猜测，无论是物质与反物质的破缺，还是生物分子的均一性，可能都与CP的不守恒有某种关系。因此，寻找CP破坏的机理，也就成为现代物理研究的重要课题之一。 第三段中“首先打破……这样的怪事”中的“怪事”指( )。
Questions 8 to 10 are based on the following conversation. At the end of the conversation, you will be given 15 seconds to answer the questions. Now, listen to the conversation. What suggestion does Nancy’s friend make
数学推理每题给你一个数列，但其中缺少一项，要求你仔细观察数列的排列规律综合判断，然后从四个供选择的选项中选出最恰当的一项，来填补空缺项。 5，8，12，18，( )。
When people care enough about something to do it well, those who do it best tend to be far better than everyone else. There’’s a huge gap between Leonardo and second-rate contemporaries. A top-ranked professional chess player could play ten thousand games against an ordinary club player without losing once. Like chess or painting or writing novels, making money is a very specialized skill. But for some reason we treat this skill differently. No one complains when a few people surpass all the rest at playing chess or writing novels, but when a few people make more money than the rest, we get editorials saying this is wrong. Why The pattern of variation seems no different than for any other skill. What causes people to react so strongly when the skill is making money I think there are three reasons we treat making money as different: the misleading model of wealth we learn as children; the disreputable way in which, till recently, most fortunes were accumulated; and the worry that great variations in income are somehow bad for society. As far as I can tell, the first is mistaken, the second outdated, and the third empirically false. Could it be that, in a modern democracy, variation in income is actually a sign of health When I was five I thought electricity was created by electric sockets. I didn’’t realize there were power plants out there generating it. Likewise, it doesn’’t occur to most kids that wealth is something that has to be generated. It seems to be something that flows from parents. Because of the circumstances in which they encounter it, children tend to misunderstand wealth. They confuse it with money. They think that there is a fixed amount of it. And they think of it as something that’’s distributed by authorities (and so should be distributed equally), rather than something that has to be created (and might be created unequally). In fact, wealth is not money. Money is just a convenient way of trading one form of wealth for another. Wealth is the underlying stuff—the goods and services we buy. When you travel to a rich or poor country, you don’’t have to look at people’’s bank accounts to tell which kind you’’ re in. You can see wealth — in buildings and streets, in the clothes and the health of the people. Where does wealth come from People make it. This was easier to grasp when most people lived on farms, and made many of the things they wanted with their own hands. Then you could see in the house, the herds, and the granary the wealth that each family created. It was obvious then too that the wealth of the world was not a fixed quantity that had to be shared out, like slices of a pie. If you wanted more wealth, you could make it. This is just as true today, though few of us create wealth directly for ourselves. Mostly we create wealth for other people in exchange for money, which we then trade for the forms of wealth we want. Because kids are unable to create wealth, whatever they have has to be given to them. And when wealth is something you’’ re given, then of course it seems that it should be distributed equally. As in most families it is. The kids see to that. "Unfair," they cry, when one sibling (兄弟姐妹) gets more than another. In the real world, you can’’t keep living off your parents. If you want something, you either have to make it, or do something of equivalent value for someone else, in order to get them to give you enough money to buy it. In the real world, wealth is (except for a few specialists like thieves and speculators) something you have to create, not something that’’s distributed by Daddy. And since the ability and desire to create it vary from person to person, it’’s not made equally. You get paid by doing or making something people want, and those who make more money are often simply better at doing what people want. Top actors make a lot more money than B-list actors. The B-list actors might be almost as charismatic, but when people go to the theater and look at the list of movies playing, they want that extra oomph (吸引力) that the big stars have. Doing what people want is not the only way to get money, of course. You could also rob banks, or solicit bribes, or establish a monopoly. Such tricks account for some variation in wealth, and indeed for some of the biggest individual fortunes, but they are not the root cause of variation in income. The root cause of variation in income is the same as the root cause of variation in every other human skill. The second reason we tend to find great disparities of wealth alarming is that for most of human history the usual way to accumulate a fortune was to steal it: in pastoral societies by cattle raiding; in agricultural societies by appropriating others’’ estates in times of war, and taxing them in times of peace. In conflicts, those on the winning side would receive the estates confiscated from the losers. In more organized societies, the ruler and his officials used taxation instead of confiscation. But here too we see the same principle: the way to get rich was not to create wealth, but to serve a ruler powerful enough to appropriate it. But it was not till the Industrial Revolution that wealth creation definitively replaced corruption as the best way to get rich. In England, at least, corruption only became unfashionable when there started to be other faster ways to get rich. Thirdly, one often hears a policy criticized on the grounds that it would increase the income gap between rich and poor. As if it were an axiom (公理) that this would be bad. It might be true that increased variation in income would be bad, but I don’’t see how we can say it’’s axiomatic. Indeed, it may even be false, in industrial democracies. In a society of serfs (农奴) and warlords, certainly, variation in income is a sign of an underlying problem. But serfdom is not the only cause of variation in income. A 747 pilot doesn’’t make 40 times as much as a checkout clerk because he is a warlord. His skills are simply much more valuable. I’’d like to propose an alternative idea: that in a modern society, increasing variation in income is a sign of health. Technology seems to increase the variation in productivity at faster than linear rates. If we don’’t see corresponding variation in income, there are three possible explanations: (a) that technical innovation has stopped, (b) that the people who would create the most wealth aren’’t doing it, or (c) that they aren’’t getting paid for it. If you suppress variations in income, whether by stealing private fortunes, as feudal rulers used to do, or by taxing them away, as some modern governments have done, the result always seems to be the same. Society as a whole ends up poorer. If I had a choice of living in a society where I was materially much better off than I am now, but was among the poorest, or in one where I was the richest, but much worse off than I am now, I’d take the first option. If I had children, it would arguably be immoral not to. It’’s absolute poverty you want to avoid, not relative poverty. If, as the evidence so far implies, you have to have one or the other in your society, take relative poverty. You need rich people in your society not so much because in spending their money or they create jobs, but because of what they have to do to get rich. I’m not talking about the trickle-down effect here. I’m not saying that if you let Henry Ford get rich, he’’ll hire you as a waiter at his next party. I’m saying that he’’ll make you a tractor to replace your horse. Many parents tell their children that wealth is something that hasn’’t to be generated. It is something that can flow from parents.
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