Oxford researchers have discovered a subatomic particle that can switch between matter and antimatter, which could change the way we view the cosmos forever.
According to Oxford physicists studying data from the Large Hadron Collider, a subatomic particle has been found to flip between matter and antimatter. It turns out that a seemingly insignificant weight differential between two particles could have rescued the cosmos from annihilation shortly after it was born.
The only fundamental distinction between antimatter and normal matter is that antimatter has the opposite charge. That means that if matter and antimatter particles collide, they will annihilate one another in a blast of energy.
To make matters more complicated, some particles, such as photons, are actually antiparticles of themselves. Others have been observed to exist as a strange blend of both states at the same time, according to the quantum quirk of superposition (best exemplified by Schrödinger’s cat’s thought experiment). This means that these particles alternate between matter and antimatter states.
The charm meson is the latest particle to enter that exclusive club. This subatomic particle is made up of a charm quark and an up antiquark in normal matter, and a charm antiquark and an up quark in antimatter. Normally, both states are maintained separate, but new research suggests that charm mesons can transition between them spontaneously.
The fact that the two states have slightly different populations eventually revealed the secret. The difference is only 0.00000000000000000000000000000000000001 grams.
“Charm meson particles are produced in proton–proton collisions and they travel on average only a few millimeters before transforming, or decaying, into other particles,” Tim Gershon, professor in the Department of Physics at the University of Warwick, said in a press release from the University of Oxford.
“By comparing the charm meson particles that decay after travelling a short distance with those that travel a little further, we have been able to measure the key quantity that controls the speed of the charm meson oscillation into anti-charm meson – the difference in mass between the heavier and lighter versions of charm meson,” he added.
Physicists at Oxford University extracted this highly exact measurement from data collected during the second run of the Large Hadron Collider. In proton-proton collisions at the LHC, charm mesons are formed, and they usually only travel a few millimeters before decaying into other particles.
The scientists discovered that differences in mass are the major factor that determines whether a charm meson develops into an anti-charm meson or not by comparing those that tend to go further with those that decay sooner.
This minuscule discovery could have massive repercussions for the universe. According to the Standard Model of particle physics, the Big Bang should have produced equal amounts of matter and antimatter, which would have interacted and annihilated over time, leaving the universe very empty. Obviously, this did not occur, and matter eventually took control, but what caused the imbalance?
One theory proposed by the new finding stated that particles like the charm meson will transition from antimatter to matter more frequently than they will move from matter to antimatter. Investigating if this is true – and, if so, why – could be a key to unlocking one of science’s deepest riddles.