Ancient neutrinos shaped the cosmos

• Autores: Anil Ananthaswamy
• Localización: New scientist, ISSN 0262-4079, Nº. 3173, 2018, pág. 16
• Idioma: inglés
• Texto completo no disponible (Saber más ...)
• Resumen

  • Neutrinos that filled the universe a mere second after the big bang make up a third "dark" component of the cosmos, alongside dark matter and dark energy. For the first time, we have detected how these particles influenced the large-scale distribution of galaxies. Daniel Baumann at the University of Amsterdam in the Netherlands and his colleagues have found evidence of these minuscule changes, by looking at the way galaxies are clustered. When the universe cooled enough to stop both types of shells from propagating outward, about 380,000 years after the big bang, they were frozen in time. The shells became regions where more galaxies eventually formed, because they were denser than other areas of space. To see the effect of the neutrinos, Baumann and his colleagues analyzed the data from a survey of roughly 1.2 million galaxies, out to a distance of about 6 billion light years, carried out by the Sloan Digital Sky Survey-Ill. Baumann's team showed that the influence of neutrinos in the early universe can be detected today in how galaxies are distributed. The shells of normal matter that were subtly stretched and distorted by neutrinos have since evolved with the expanding universe. The shape and size of these shells, determined by an excess of galaxies in these regions today, are consistent with our ideas of that warp.