IAS Gyan

Daily News Analysis

Space-time induces neutrino oscillations

18th June, 2021 Science and Technology

GS PAPER III: Science and Technology- developments and their applications and effects in everyday life.

Context: Scientists have shown that the geometry of space-time can cause neutrinos to oscillate.

Neutrinos

  • They are mysterious particles, produced copiously in nuclear reactions in the Sun, stars, and elsewhere.
  • They also "oscillate"-- meaning that different types of neutrinos change into one another – as has been found in many experiments.
  • Probing of oscillations of neutrinos and their relations with mass are crucial in studying the origin of the universe.
  • Neutrinos interact very weakly with everything else – trillions of them pass through every human being every second without anyone noticing.
  • A neutrino’s spin always points in the opposite direction of its motion, and until a few years ago, neutrinos were believed to be massless.
  • It is now generally believed that the phenomenon of neutrino oscillations require neutrinos to have tiny masses.

Space-time induced oscillations

  • Einstein’s theory of general relativity says that gravitation is the manifestation of space-time curvature.
  • Neutrinos, electrons, protons and other particles, which are in the category of fermions show a certain peculiarity when they move in presence of gravity.
  • Space-time induces a quantum force in addition to gravity between every two fermions.
  • This force can depend on the spin of the particles, and causes massless neutrinos to appear massive when they pass through matter, like the Sun’s corona or the Earth’s atmosphere.
  • Something similar happens for electroweak interactions, and together with the geometrically induced mass it is enough to cause oscillation of neutrinos.

https://pib.gov.in/PressReleasePage.aspx?PRID=1727904