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题库 / OG2016-RC-138
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.
The passage implies that if tunneling time reached no maximum in increasing with barrier thickness, then
tunneling speed would increase with barrier thickness
tunneling speed would decline with barrier thickness
tunneling speed would vary with barrier thickness
tunneling speed would not be expected to increase without limit
successful tunneling would occur even less frequently than it does
题目分析：
文章推断题：文章暗示了如果穿行时间没有到达最大值，随着厚度增加，
选项分析：
A选项：速度会随着厚度增加：时间没有达到最大值，速度就会受厚度速度两者的影响而变化。
B选项：速度会随着厚度减小。
C选项：速度会随着厚度变化。
D选项：正确。速度不会无限增加：原文说时间长到一定程度，速度就会随着厚度无限增加， 既然时间没有达到最大值，那么速度就不会无限增加。
E选项：即使频率更小，会有成功的隧道穿行：无关。
it takes a particle to tunnel through a barrier increases with the thickness of the barrier until tunneling time reaches a maximum
文章只说了时间随着厚度增加而增加，并没有说速度如何，注意读题时的思维逻辑不要陷入逻辑误区。
可能只是厚度大了，时间长了，速度没有增加，即可能变慢也可能速度不变。
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找原文 不要瞎算
once maximum tunneling time is reached, tunneling speed will increase without limit as barrier thickness increases. 漏看了no
This would imply that once maximum tunneling time is reached, tunneling speed will increase without limit as barrier thickness increases.一旦达到一定程度，速度就会无限增加。那么没有达到就不会无限增加
This would imply that once maximum tunneling time is reached, tunneling speed will increase without limit as barrier thickness increases.
rc
简单题；注意题干陷阱“reached no maximum” no
定位： 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.
问的是计算结果，所以是定位 this would imply....
问题是reach no maximum, 认真审题！
This would imply that once maximum tunneling time is reached, tunneling speed will increase without limit as barrier thickness increases. 取非就是答案
This would imply that once maximum tunneling time is reached, tunneling speed will increase without limit as barrier thickness increases.
直到的关系：once maximum, will increase without limit = no maximum, not increase without limit
只有D是原文明确提到的，到达maximum才会increase without limit，那没达到就是反之的结果
原文没说 又是自己主观猜想
时间，速度，障碍物的厚度关系：时间达到最大值，速度和厚度一直增长；如果时间不达到最大值，速度和厚度就不用一直增长
直到的关系：once maximum, will increase without limit = no maximum, not increase without limit
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.
once max, will increase without limit = no max, not increase without limit
是”直到...才“的关系
This would imply that once maximum tunneling time is reached, tunneling speed will increase without limit as barrier thickness increases－－－时间超越了最大值，之后不变，厚度增加，速度随之无限制的增加。即：拐点之后，速度才会无限制增加----拐点之前，速度就不会没有限制的增加
D would not!!