Experimentally, a light pulse propagating through the atomic vapor cell has its peak reaching the exit side before entering it, resulting in a negative transit time, and negative group velocity.

研究发现，当光脉冲通过一个原子气室时，在进入前其峰即到达出口处，造成负渡越时间和负群速。

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Thirty seconds later, at a quiet exit on the east side of the Capitol, the powerfully built blond man in the blue blazer stepped into the damp night air.

三十秒之后，在国会大厦东侧一个安静的出口处，那个穿着蓝色上衣，体格健壮的金发男人步入了夜间潮湿的空气中。

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In two days, two prominent central bankers, one on each side of the Atlantic, headed for the exit.

两天之内，两位杰出的中央银行行长，虽然身处大西洋两岸，却都选择了退出。

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Dale Connone was getting ready to disembark from the boat's side exit when the ferry crashed.

WSJ: A Low-Key Commute on the Water, Then, 'All of Us Standing Went Flying'

There was billionaire Ted Turner, who briskly made his exit on the early side of the evening, and former Virginia Gov. (now Richmond Mayor) Doug Wilder, who looked a bit dazed.

FORBES: And They're Off!

He has two entry wounds in his side and two exit wounds.

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