According to classical theory, at the boundary of a black hole-the so-called event horizon-light can no longer escape.

在经典理论中，在黑洞的边界，即通常所称的事件穹界，光是不能逃逸的。

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To be sucked in by a black hole, you need to reach its event horizon, the one-way boundary beyond which nothing can escape.

要被一个黑洞吸入，你必须抵达它的视界，即：超过这个边界任何都无法逃离的单程边界。

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In the distant horizon where nature and human civilization meet, the boundary between science and arts vanishes.

在那遥远的天际，自然与人类文明相遇，而科学与人文艺术间的界限也变得模糊。

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In physics, the Event Horizon occurs at the boundary of all black holes.

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In other words, the boundary between the supersonic and subsonic regions would do for sound waves what the event horizon does for light.

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