PARIS: Scientists have observed the fifth state of matter in space for the first time, offering unprecedented insight that could help solve some of the quantum universe's most intractable conundrums, research showed Thursday.
Bose-Einstein condensates (BECs) - the existence of which was predicted by Albert Einstein and Indian mathematician Satyendra Nath Bose almost a century ago - are formed when atoms of certain elements are cooled to near absolute zero (0 Kelvin, minus 273.15 Celsius). At this point, the atoms become a single entity with quantum properties, wherein each particle also functions as a wave of matter.
BECs straddle the line between the macroscopic world governed by forces such as gravity and the microscopic plane, ruled by quantum mechanics.
Scientists believe BECs contain vital clues to mysterious phenomena such as dark energy - the unknown energy thought to be behind the Universe's accelerating expansion. But BECs are extremely fragile. The slightest interaction with the external world is enough to warm them past their condensation threshold. This makes them nearly impossible for scientists to study on Earth, where gravity interferes with the magnetic fields required to hold them in place for observation. On Thursday a team of NASA scientists unveiled the first results from BEC experiments aboard the International Space Station, where particles can be manipulated free from Earthly constraints.
"Microgravity allows us to confine atoms with much weaker forces, since we don't have to support them against gravity," Robert Thompson of from the California Institute for Technology, Pasadena, told AFP. The research published in the journal Nature documents several startling differences in the properties of BECs created on Earth and those aboard the ISS. For one thing, BECs in terrestrial labs typically last a handful of milliseconds before dissipating. Aboard the ISS the BECs lasted more than a second, offering the team an unprecedented chance to study their properties.
Microgravity also allowed the atoms to be manipulated by weaker magnetic fields, speeding their cooling and allowing clearer imaging.
Creating the fifth state of matter, especially within the physical confines of a space station, is no mean feat.
First, bosons - atoms that have an equal number of protons and electrons - are cooled to absolute zero using lasers to clamp them in place. The slower the atoms move around, the cooler they become. As they lose heat, a magnetic field is introduced to keep them from moving and each particle's wave expands.
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