The acoustic properties of an ultracold fermion gas have been measured either side of the superfluid transition temperature in an experiment that has been described as “near perfect” and “beautiful”.

When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. This exercise was largely theoretical: The researchers found that the answer, which is about ...

Although few people ever get the chance to travel at the speed of sound, it is an alluring flight goal and an impressive technological feat. Though average people have flown at high speeds on ...