实验室中模拟超新星爆炸

A team of physicists¹ from the University of Toronto and Rutgers University have mimicked² the explosion of a supernova（超新星） in miniature（小型，小规模） . A supernova is an exploding star. In a certain type of supernova, the detonation³（爆炸） starts with a flame ball buried deep inside a white dwarf⁴. The flame ball is much lighter⁵ than its surroundings, so it rises rapidly making a plume⁶ topped with an accelerating smoke ring.

"We created a smaller version of this process by triggering a special chemical reaction in a closed container that generates similar plumes⁷ and vortex rings（涡环） ," says Stephen Morris, a University of Toronto physics professor.

Autocatalytic（自动催化的） chemical reactions release heat and change the composition of a solution, which can create buoyancy forces（浮力） that can stir the liquid, leading to more reaction and a runaway⁸ explosive process. "A supernova is a dramatic example of this kind of self-sustaining explosion in which gravity and buoyancy forces are important effects. We wanted to see what the liquid motion would look like in such a self-stirred chemical reaction," says Michael Rogers, who led the experiment as part of his PhD research, under the supervision⁹ of Morris.

"It is extremely difficult to observe the inside of a real exploding star light years away so this experiment is an important window into the complex fluid motions that accompany such an event," Morris explains. "The study of such explosions in stars is crucial to understanding the size and evolution of the universe."