跟希哥学英语 第80期:探索宇宙

 　　Questioning the universe

　　Stephen Hawking¹

　　There is nothing bigger or older than the universe. The questions I would like to talk about are: one, where did we come from? How did the universe come into being? Are we alone in the universe? Is there alien life out there? What is the future of the human race?

　　Up until the 1920s, everyone thought the universe was essentially² static and unchanging in time. Then it was discovered that the universe was expanding. Distant galaxies³ were moving away from us. This meant they must have been closer together in the past. If we extrapolate back, we find we must have all been on top of each other about 15 billion years ago. This was the Big Bang, the beginning of the universe.

　　But was there anything before the Big Bang? If not, what created the universe? Why did the universe emerge from the Big Bang the way it did? We used to think that the theory of the universe could be divided into two parts. First, there were the laws like Maxwell's equations and general relativity that determined⁴ the evolution of the universe, given its state over all of space at one time. And second, there was no question of the initial state of the universe.

　　探索宇宙

　　We have made good progress on the first part, and now have the knowledge of the laws of evolution in all but the most extreme conditions. But until recently, we have had little idea about the initial conditions for the universe. However, this division into laws of evolution and initial conditions depends on time and space being separate and distinct. Under extreme conditions, general relativity and quantum theory allow time to behave like another dimension of space. This removes the distinction between time and space, and means the laws of evolution can also determine the initial state. The universe can spontaneously create itself out of nothing.

　　Moreover, we can calculate a probability that the universe was created in different states. These predictions are in excellent agreement with observations by the WMAP satellite of the cosmic microwave background, which is an imprint⁵ of the very early universe. We think we have solved the mystery of creation. Maybe we should patent the universe and charge everyone royalties⁶ for their existence.

　　I now turn to the second big question: are we alone, or is there other life in the universe? We believe that life arose spontaneously on the Earth, so it must be possible for life to appear on other suitable planets, of which there seem to be a large number in the galaxy⁷.

　　But we don't know how life first appeared. We have two pieces of observational evidence on the probability of life appearing. The first is that we have fossils of algae⁸ from 3.5 billion years ago. The Earth was formed 4.6 billion years ago and was probably too hot for about the first half billion years. So life appeared on Earth within half a billion years of it being possible, which is short compared to the 10-billion-year lifetime of a planet of Earth type. This suggests that a probability of life appearing is reasonably high. If it was very low, one would have expected it to take most of the ten billion years available.

　　On the other hand, we don't seem to have been visited by aliens. I am discounting the reports of UFOs. Why would they appear only to cranks and weirdoes? If there is a government conspiracy⁹ to suppress the reports and keep for itself the scientific knowledge the aliens bring, it seems to have been a singularly ineffective policy so far. Furthermore, despite an extensive search by the SETI project, we haven't heard any alien television quiz shows. This probably indicates that there are no alien civilizations at our stage of development within a radius¹⁰ of a few hundred light years. Issuing an insurance policy against abduction by aliens seems a pretty safe bet.

　　This brings me to the last of the big questions: the future of the human race. If we are the only intelligent beings in the galaxy, we should make sure we survive and continue. But we are entering an increasingly dangerous period of our history. Our population and our use of the finite resources of planet Earth are growing exponentially, along with our technical ability to change the environment for good or ill. But our genetic¹¹ code still carries the selfish and aggressive instincts that were of survival advantage in the past. It will be difficult enough to avoid disaster in the next hundred years, let alone the next thousand or million.

　　Our only chance of long-term survival is not to remain lurking¹² on planet Earth, but to spread out into space. The answers to these big questions show that we have made remarkable¹³ progress in the last hundred years. But if we want to continue beyond the next hundred years, our future is in space. That is why I am in favor of manned -- or should I say, personed -- space flight.

　　All of my life I have sought to understand the universe and find answers to these questions. I have been very lucky that my disability has not been a serious handicap. Indeed, it has probably given me more time than most people to pursue the quest for knowledge. The ultimate goal is a complete theory of the universe, and we are making good progress. Thank you for listening.

1 hawking   

利用鹰行猎

参考例句：

• He is hawking his goods everywhere. 他在到处兜售他的货物。
• We obtain the event horizon and the Hawking spectrumformula. 得到了黑洞的局部事件视界位置和Hawking温度以及Klein—Gordon粒子的Hawking辐射谱。

2 essentially   

adv.本质上，实质上，基本上

参考例句：

• Really great men are essentially modest.真正的伟人大都很谦虚。
• She is an essentially selfish person.她本质上是个自私自利的人。

3 galaxies   

星系( galaxy的名词复数 )； 银河系； 一群（杰出或著名的人物）

参考例句：

• Quasars are the highly energetic cores of distant galaxies. 类星体是遥远星系的极为活跃的核心体。
• We still don't know how many galaxies there are in the universe. 我们还不知道宇宙中有多少个星系。

4 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。

5 imprint   

n.印痕，痕迹；深刻的印象；vt.压印，牢记

参考例句：

• That dictionary is published under the Longman imprint.那本词典以朗曼公司的名义出版。
• Her speech left its imprint on me.她的演讲给我留下了深刻印象。

6 royalties   

特许权使用费

参考例句：

• I lived on about £3,000 a year from the royalties on my book. 我靠着写书得来的每年约3，000英镑的版税生活。 来自辞典例句
• Payments shall generally be made in the form of royalties. 一般应采取提成方式支付。 来自经济法规部分

7 galaxy   

n.星系；银河系；一群(杰出或著名的人物)

参考例句：

• The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
• The company has a galaxy of talent.该公司拥有一批优秀的人才。

8 algae   

n.水藻，海藻

参考例句：

• Most algae live in water.多数藻类生长在水中。
• Algae grow and spread quickly in the lake.湖中水藻滋蔓。

9 conspiracy   

n.阴谋，密谋，共谋

参考例句：

• The men were found guilty of conspiracy to murder.这些人被裁决犯有阴谋杀人罪。
• He claimed that it was all a conspiracy against him.他声称这一切都是一场针对他的阴谋。

10 radius   

n.半径，半径范围；有效航程，范围，界限

参考例句：

• He has visited every shop within a radius of two miles.周围两英里以内的店铺他都去过。
• We are measuring the radius of the circle.我们正在测量圆的半径。

11 genetic   

adj.遗传的，遗传学的

参考例句：

• It's very difficult to treat genetic diseases.遗传性疾病治疗起来很困难。
• Each daughter cell can receive a full complement of the genetic information.每个子细胞可以收到遗传信息的一个完全补偿物。

12 lurking   

潜在

参考例句：

• Why are you lurking around outside my house? 你在我房子外面鬼鬼祟祟的，想干什么？
• There is a suspicious man lurking in the shadows. 有一可疑的人躲在阴暗中。 来自《现代英汉综合大词典》

13 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。