The principle of equivalence is a vital component of Einstein’s theory of general relativity. This principle states that inertial mass (resistance of an object to acceleration) and gravitational mass (gravitational attraction of an object to others) are the same. He illustrated this with a thought experiment involving an elevator: if he were to cut its cable and cause it to fall freely, the passengers inside would feel weightlessness as if gravity didn’t exist, because their inertial mass from falling would be identical to the gravitational mass they experience. Read full article here
Science
‘Ghostly’ neutrinos provide new path to study protons
In groundbreaking research, an international collaboration of scientists from the University of Rochester have used a beam of neutrinos to measure the size and shape of the protons that make up the nuclei of atoms. This feat, once thought impossible, provides scientists with a new way of looking at the small components of an atom’s nucleus and opens up a wealth of new information about the structure of an atom’s nucleus and the dynamics of the forces that affect neutrino interactions. The researchers solved the challenge of harnessing neutrinos in large numbers by using a neutrino detector containing a target of both hydrogen and carbon atoms, and over nine years of data collection at Fermilab’s accelerator. Read full article here