Description
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
