Lately, the Physicists have made the most precise measurement of how strongly the weak force — one of nature's four fundamental forces — acts on the proton.One of the steps towards a more complete theory is to test what the Standard Model has to say about the weak force.
This week force is the key reason behind radioactive decay. This radioactive decay enables the nuclear reactions that keep the sun shining and drive nuclear power plants. The weak forces’ strength depends upon a particle's so-called weak charge, in the same way as the electromagnetic force depends on electric charge and gravity depends on mass. Proton’s weak charge was measured for the first time by 100 scientists from more than 20 institutions. The researchers blasted beams of electrons at a pool of protons. The spins of the electrons were either parallel or anti-parallel with the beam. When the electrons collided with the protons, they scattered as a result of interactions involving the electromagnetic force. But for every 10,000 or 100,000 scatterings, one happened via the weak force. The researchers observed that the difference in scattering probability was a mere 226.5 parts per billion, with a precision of 9.3 parts per billion. Although, the proton's weak charge turned out to be almost what the Standard Model stated it would be, all hope is not lost for finding new physics at some point in the future. What is yet to be seen is that what those new physics might look like.
By: Anuja Arora