Physicists have developed a new mathematical model that sheds light on the condensation of an ideal gas of fermions, made of elementary particles or atoms, helping to better understand their properties in a new phase1.

There are two types of elementary particles – bosons and fermions, which behave very differently at ultracold temperatures.

Bosons such as photons can collapse into the same quantum ground state, making them form a state of condensed matter known as Bose-Einstein condensate (BEC). Fermions such as electrons cannot occupy the same quantum state.

Physicist Arnab Ghosh from the Weizmann Institute of Science in Israel along with Deb Shankar Ray from the Indian Association for the Cultivation of Science in Kolkata developed the mathematical model to describe the condensation of an ideal fermionic gas.

For the first time, they named the gas Born-Kothari condensate (BKC) after the physicists Max Born and Daulat Singh Kothari who conceived the basic concept. BKC’s condensation is primarily guided by the density of states of particles.

Bosons form coherent matter wave at the lowest energy state; while the fermions in BKC only occurs in the form of a dense band at the highest energy state.

“In the future, it would be possible to taste the existence of BKC in lab by using a fermionic gas of potassium atoms. This could shed light on the properties of elementary particles of astrophysical significance,” says Ghosh, the lead author.