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(5) be impenetrable. (專有名詞後配修飾語定義:可能考細節題) If you throw a ball at a wall, you expect it to bounce back, not to pass straight through it. (類比/舉例:可能考作用題)Yet subatomic particles perform the equivalent feat. (看到Yet 轉折關鍵字先判斷有無態度上的轉換:這邊沒有,只是在做對比)(對比考相同相異)Quantum theory says that there is a distinct, albeit small, probability that such a particle(10) will tunnel its way through a barrier;(出現「理論」,可能考細節題) the probability declines exponentially as the thickness of the barrier increases.(出現thickness 跟probability的線性關係:可能考推論題)


Though the extreme rapidity of quantum tunneling was noted as early as 1932, not until 1955 was it hypothesized—by Wigner and(15) Eisenbud —that tunneling particles sometimes travel faster than light. (看到though 讓步關鍵字先判斷有無態度:這邊沒有,只是在做事實的對比)(對比考相同相異)(兩個以上的年代出現:可能考細節題)(看到人提出想法:「W跟E hypothesized」,可能會考何者為真題:W.E.會認同下列何敘述)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(20) 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(25) increases. (看到tunneling time與barrier thickness的線性關係:可能考推論題)

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(30) an optical filter at 1.7 times the speed of light. (證據、舉例:考作用)

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