Physicists at Washington State University have created a fluid with negative mass. It does the opposite of mass when it gets pushed; it accelerates backwards instead of going toward the direction it was pushed.
This is an interesting development since the phenomenon is hardly created in laboratory conditions. This can also be used for a deeper understanding of the more difficult concepts of the cosmos.
The research is published in the journal "Physical Review Letters." It is featured as an "Editor's Suggestion."
In WSU's official website, it was hypothesized that matter can have negative mass - the same way that an electric charge can be either negative or positive. In the everyday world, though, this is not a common way of thinking.
People only see the positive side of Newton's Second Law of Motion where a force is equal to the mass of an object times its acceleration. With negative mass, when it gets pushed, it accelerates toward the one who pushed it.
Researchers created the conditions for negative mass by cooling rubidium atoms to just a little above absolute zero. This resulted to what is known as a Bose-Einstein condensate.
In this state, particles move very slowly and behave similar to waves. They also synchronize and move in unison like a superfluid, which flows without the use of energy.
Peter Engels, WSU professor of physics and astronomy, led the study by using lasers to slow the particles, making them colder. It also allowed hot, high energy particles to escape like steam thus cooling the material further.
The lasers trapped the atoms and, to create negative mass, the researchers applied a second set of lasers that kicked the atoms back and forth as well as changed the way the spun. When the rubidium rushes out fast enough, it behaves as if it has negative mass.
The researchers were able to avoid some of the underlying defects encountered in previous attempts to understand negative mass. The heightened control gave them a new way to engineer experiments and study analogous physics in astrophysics and cosmological phenomena.
