“吸血鬼树”何处吸取养分？盘点2019年最怪异10项科学研究_BEC初级作文

“吸血鬼树”何处吸取养分？盘点2019年最怪异10项科学研究

如果科学家向一股水流发射极细的X射线激光，它会发出声音吗？是的，它会。今年，研究人员利用这样一种装置制造出了可能是最响亮的水下声音。在真空容器内，X射线激光的脉冲光束与像刀片一样薄的水射流相撞，瞬间将射流一分为二，并使两侧的液体汽化。压力波从接触点开始扩散，发出270分贝的声音，比美国国家航空航天局史上最响亮的火箭发射声音还要大。如果声音再大一点，就有可能令它穿过的液体沸腾。

黑洞会蒸发吗？

Famed theoretical physicist and cosmologist Stephen Hawking once predicted that black holes not only suck celestial objects into their depths but also emit particles into space. He theorized that these particles slowly strip black holes of their mass and energy, until eventually, the black hole disappears — but physicists never thought they could prove it.

著名理论物理学家兼宇宙学家斯蒂芬·霍金曾预言，黑洞不仅将天体吸入其深处，而且会向太空发射粒子。他的理论是，这些粒子会慢慢带走黑洞的质量和能量，直到黑洞最终消失——但物理学家从未想过他们能够证明这一点。

This year, however, a team of researchers finally spotted this elusive Hawking radiation in laboratory experiments. The team created a "waterfall" from a stream of extremely cold gas to model the event horizon of a black hole, the invisible boundary beyond which nothing can escape. Quantum sound waves fed into the gas could flow away from the waterfall if inserted into the "stream" nearby, but sound waves in the waterfall itself became trapped by the relentless current. The escaped sound waves can be seen as analogous to particles of light escaping the pull of a black hole, suggesting that Hawking's theory was right.