Atoms cooled to “colder than absolute zero”.
German physicists have demonstrated a way to cool atoms to a point below minus 459.67 degrees Fahrenheit (minus 273.15 degrees Celsius), and into a realm described as ‘negative temperatures’.
To achieve the feat, the team cooled atoms to near absolute zero in a vacuum chamber, to avoid heating from any external influence. They then used lasers and magnetic fields to push the atoms into “negative nanokelvin”.
To comprehend the negative temperatures scientists have now devised, one might think of temperature as existing on a scale that is actually a loop, not linear. Positive temperatures make up one part of the loop, while negative temperatures make up the other part. When temperatures go either below zero or above infinity on the positive region of this scale, they end up in negative territory.
A potential use for the discovery could be to create ‘heat engines’ that are more than 100% efficient:
Such engines would essentially not only absorb energy from hotter substances, but also colder ones. As such, the work the engine performed could be larger than the energy taken from the hotter substance alone.