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题库 / OG2016-RC-139
Most attempts by physicists to send particles faster than the speed of light involve a remarkable phenomenon called quantum tunneling, in which particles travel through solid barriers that appear to be impenetrable. If you throw a ball at a wall, you expect it to bounce back, not to pass straight through it. Yet subatomic particles perform the equivalent feat. Quantum theory says that there is a distinct, albeit small, probability that such a particle will tunnel its way through a barrier; the probability declines exponentially as the thickness of the barrier increases. Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light. Their grounds were calculations that suggested that the time it takes a particle to tunnel through a barrier increases with the thickness of the barrier until tunneling time reaches a maximum; beyond that maximum, tunneling time stays the same regardless of barrier thickness. This would imply that once maximum tunneling time is reached, tunneling speed will increase without limit as barrier thickness increases. Several recent experiments have supported this hypothesis that tunneling particles sometimes reach superluminal speed. According to measurements performed by Raymond Chiao and colleagues, for example, photons can pass through an optical filter at 1.7 times the speed of light.
Which of the following statements about the earliest scientific investigators of quantum tunneling can be inferred from the passage?
They found it difficult to increase barrier thickness continually.
They anticipated the later results of Chiao and his colleagues.
They did not suppose that tunneling particles could travel faster than light.
They were unable to observe instances of successful tunneling.
They made use of photons to study the phenomenon of tunneling.
题目分析：
文章推断题：关于早期的量子隧道效应的研究，研究者可能
选项分析：
A选项：发现很难一直增加厚度：原文没有提增加厚度的难易度。
B选项：期待之后C的研究成果：原文没有提。
C选项：正确。没指望粒子会比光快：原文说到即使早在1932年就发现了量子隧道效应的极速，但直到1955年才假设粒子有时候会比光的速度还快。说明早期的研究者没有假设粒子的速度比光速还快。
D选项：没能力观察成功的隧道穿行：没提。
E选项：用光子（photons）研究隧道现象：文章只说了RC研究了光子，没提到是否早期的学者也研究了。
earlist 时间相关
Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light.
只有这句话涉及时间，1932年认为not travel faster than light.
细节题，定位"Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized—by Wigner and Eisenbud—[that tunneling particles sometimes travel faster than light]."（本句话较长，又有两个破折号，定位的时候不要粗心或者着急导致遗漏了信息就可以轻松找到答案）
that tunneling particles sometimes travel faster than light1955才第一次说可能会比光还快，C
not until 1955 was it hypothesized
rc
简单题
定位：
Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized（倒装，it was not hypothesized until..）—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light.
Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light.
1. 理论证明
2. 科学家计算
3. 实验证明 三个why证明argument的可能性
not until 1955 was it hypothesized—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light
not until 1955 was it hypothesized—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light.
32年的人已经知道tunneling了，但知道55年，才有人做出tunneling粒子可以超光速的假设
Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light.
定位没定位到这一句，看到earliest就只顾前面的了。。
Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized—by Wigner and Eisenbud—that tunneling particles sometimes travel faster than light.
D错的原因是这种现象在1930s年代就被注意到了，那被注意到，不就说明成功观察到了粒子的穿透吗？这很好想明白，因为如果没有观测到或者现象没发生，粒子会反弹，自然没人注意到。
一个理解是：文章整段都在说particles可以超光速运行，所以开始科学家并没有想到他可以超光速，而是认为他应该像球一样打到墙壁会反弹回来，但是没有。所以答案应该是suppose blabla。D明显和文章想说光速的事情不搭。所以C比D更好。
说 D 错的举得 support 是这句“Though the extreme rapidity of quantum tunneling was noted as early as 1932" ，这和 successful tunneling 是一回事？
就他们知道particle可以tunneling，这个已经被认可了。但这个点的重心本来就不在particle tunneling是否能被successfully observed呀。
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要哭了。。。在 C，D 里面纠结了好久，我知道这个地方出题人明显是想在考 C，可是我还是想知道 D 为啥不对啊。这是 OG 的解释。D The passage indicates that by 1932, investigators had noted the rapidity of quantum tunneling; although this does not entail that they observed the phenomenon, it is consistent with their having been able to do so. 我太懂，连假设都没做出来，怎么可能观察到 tunnel 成功的情况呢？？？
定位在这句Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized that tunneling particles sometimes travel faster than light
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