《英语流行话题阅读:语境识词4500》95 Scientists Look Forward to the Past

　　Unit 95
Scientists Look Forward to the Past
Can time travel really be done? Physicists² think that travel into future is possible. Einstein's special theory of relativity, published in 1905, predicted that time should be elastic³, stretching or shrinking as an observer moves. To get a really big time leap it is necessary to travel at near the speed of light -- 300,000 km per second. At 99% of this speed, a rocket trip to a distant star and back would take 15 months, but travelers would return home to find that nearly nine years had elapsed on Earth. In effect, you would have leapt several years into Earth's future.
Gravity offers another way to slow time. On the earth's surface, clocks tick a little slower than on the moon, for example. Near a neutron⁴ star or black hole, gravity is so intense that time is slowed to a crawl relative to us. These facts are accepted by almost all scientists. Traveling forwards in time has been demonstrated convincingly in experiments. But the possibility f traveling backwards⁵ in time is far more controversial. The first hint that it might be possible came in 1932, when a physicist¹ named Stockhum investigated what might happen to an observer who orbits a rapidly spinning cylinder⁶. He showed it was possible to travel in a closed loop and return to your starting point before you left.
Worm holes are like black holes, with a key difference. Whereas black holes offer a one-way journey to nowhere -- fall in and you never get out -- worm holes have an exit as well as an entrance. To find whether such an idea can be taken seriously, scientists at California Institute of Technology investigated what it would take for such a short cut though space to exist. They found that if you tried to make a worm hole out of any normal form of matter, it would collapse⁷ under its own gravity and turn into a black hole. For a worm hole remain stable, it would have to be made of exotic material that would create an anti-gravity force. Physicists know of peculiar⁸ states of matter that generate anti-gravity, and a worm hole is not physically⁹ impossible. It dawned on them that such a structure could be adapted to make a time machine that would allow an astronaut to leap instantaneously into both the past and the future. Go through the worm hole one way, and you reach the future. Go through the other way and you come out in the past.
Making a worm hole presents formidable engineering challenges, but suppose it could be done, and time travel became a reality? Thorny¹⁰ paradoxes¹¹ loom¹². What happens to the time traveler who goes back and murders his mother as a girl? If so, who murdered the mother? Does that mean he was never born? Because the present is linked to the past, you cannot change the past without unleashing¹³ causal disorder¹⁴. Since the purpose of science is to give a rational account of reality, any theory that permits paradoxical consequences is suspect. Does this mean Einstein's theory of relativity is wrong, or that worm holes could never form?
Although theoretical investigations¹⁵ of time travel are a popular topic among physicists, there is no consensus¹⁶ on how to handle the ensuing paradoxes. But one thing is agreed. Once a time machine is made, you could visit the year 2100, check out the stock prices, and then pop back and make the right investments to repay the loan.

1 physicist   

n.物理学家，研究物理学的人

参考例句：

• He is a physicist of the first rank.他是一流的物理学家。
• The successful physicist never puts on airs.这位卓有成就的物理学家从不摆架子。

2 physicists   

物理学家( physicist的名词复数 )

参考例句：

• For many particle physicists, however, it was a year of frustration. 对于许多粒子物理学家来说，这是受挫折的一年。 来自英汉非文学 - 科技
• Physicists seek rules or patterns to provide a framework. 物理学家寻求用法则或图式来构成一个框架。

3 elastic   

n.橡皮圈，松紧带；adj.有弹性的；灵活的

参考例句：

• Rubber is an elastic material.橡胶是一种弹性材料。
• These regulations are elastic.这些规定是有弹性的。

4 neutron   

n.中子

参考例句：

• Neutron is neutral and slightly heavier than the proton.中子是中性的，比质子略重。
• Based on the neutron energy,the value of weighting factor was given.根据中子能量给出了相应的辐射权重因子的数值。

5 backwards   

adv.往回地，向原处，倒，相反，前后倒置地

参考例句：

• He turned on the light and began to pace backwards and forwards.他打开电灯并开始走来走去。
• All the girls fell over backwards to get the party ready.姑娘们迫不及待地为聚会做准备。

6 cylinder   

n.圆筒，柱(面)，汽缸

参考例句：

• What's the volume of this cylinder?这个圆筒的体积有多少？
• The cylinder is getting too much gas and not enough air.汽缸里汽油太多而空气不足。

7 collapse   

vi.累倒；昏倒；倒塌；塌陷

参考例句：

• The country's economy is on the verge of collapse.国家的经济已到了崩溃的边缘。
• The engineer made a complete diagnosis of the bridge's collapse.工程师对桥的倒塌做了一次彻底的调查分析。

8 peculiar   

adj.古怪的，异常的；特殊的，特有的

参考例句：

• He walks in a peculiar fashion.他走路的样子很奇特。
• He looked at me with a very peculiar expression.他用一种很奇怪的表情看着我。

9 physically   

adj.物质上，体格上，身体上，按自然规律

参考例句：

• He was out of sorts physically,as well as disordered mentally.他浑身不舒服，心绪也很乱。
• Every time I think about it I feel physically sick.一想起那件事我就感到极恶心。

10 thorny   

adj.多刺的，棘手的

参考例句：

• The young captain is pondering over a thorny problem.年轻的上尉正在思考一个棘手的问题。
• The boys argued over the thorny points in the lesson.孩子们辩论功课中的难点。

11 paradoxes   

n.似非而是的隽语，看似矛盾而实际却可能正确的说法( paradox的名词复数 )；用于语言文学中的上述隽语；有矛盾特点的人[事物，情况]

参考例句：

• Contradictions and paradoxes arose in increasing numbers. 矛盾和悖论越来越多。 来自辞典例句
• As far as these paradoxes are concerned, the garden definitely a heterotopia. 就这些吊诡性而言，花园无疑地是个异质空间。 来自互联网

12 loom   

n.织布机，织机；v.隐现，(危险、忧虑等)迫近

参考例句：

• The old woman was weaving on her loom.那位老太太正在织布机上织布。
• The shuttle flies back and forth on the loom.织布机上梭子来回飞动。

13 unleashing   

v.把（感情、力量等）释放出来，发泄( unleash的现在分词 )

参考例句：

• Company logos: making people's life better by unleashing Cummins power. 公司理念：以康明斯动力建设更美好的生活！ 来自互联网
• Sooner or later the dam will burst, unleashing catastrophic destruction. 否则堤坝将崩溃，酿成灾难。 来自互联网

14 disorder   

n.紊乱，混乱；骚动，骚乱；疾病，失调

参考例句：

• When returning back,he discovered the room to be in disorder.回家后，他发现屋子里乱七八糟。
• It contained a vast number of letters in great disorder.里面七零八落地装着许多信件。

15 investigations   

（正式的）调查( investigation的名词复数 )； 侦查； 科学研究； 学术研究

参考例句：

• His investigations were intensive and thorough but revealed nothing. 他进行了深入彻底的调查，但没有发现什么。
• He often sent them out to make investigations. 他常常派他们出去作调查。

16 consensus   

n.(意见等的)一致，一致同意，共识

参考例句：

• Can we reach a consensus on this issue?我们能在这个问题上取得一致意见吗？
• What is the consensus of opinion at the afternoon meeting?下午会议上一致的意见是什么？