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Lithium in the Big Bang

Modeling a fraction of the surface of an ancient star: lithium quantities match theory

Karin ?Lind, Davide de MartinModeling a fraction of the surface of an ancient star: lithium quantities match theoryKarin ?Lind, Davide de Martin

More evidence to support the Big Bang theory, which claims that a primordial explosion created the universe about 13.8 billion years ago, was produced by an international group of astrophysicists including Jorge Meléndez of the University of São Paulo (USP). The scientists used the 10 m mirror and the powerful spectrograph of the Keck Telescope, located on Mauna Kea (Hawaii), to refine the measurements of the levels of two lithium isotopes in four very old stars formed shortly after the Big Bang (Astronomy & Astrophysics, June 6, 2013). Until now, there had been a large discrepancy between what the model for the creation of the universe predicted and the measurements taken. In comparison with the amounts postulated by the theory, 200 times more lithium-6 and 3 to 5 times less lithium-7 had been found in previously analyzed stars. The new measurements using the Keck, however, found values within the ranges estimated using the Big Bang model. The greatest difficulty in this type of search is obtaining evidence of the signature of lithium-6, the least abundant form of this element in the universe. “The Keck’s great light collecting power allowed us to observe stars with a more ‘primordial’ composition than in any previous study,” said Meléndez. The data collected was analyzed with the use of sophisticated three-dimensional computer modeling of the stars’ atmosphere, a strategy that allowed them to obtain more detailed information, the researchers said.