The RIKEN-led BASE collaboration at Geneva has found that matter and antimatter respond to gravity in the same way. Scientists tried to measure the charge-to-mass ratios of protons and antiprotons.
Matter and antimatter create some interesting problems. But they are equivalent. But a particle has a positive charge and antiparticle has a negative charge. But “baryon asymmetry” is one of the great mysteries of physics. Despite the fact that they both are equivalent, but our universe is mainly made of matter and has a little antimatter. Scientists have tried to explain something different between the two. This can give us insights about why we exist.
The scientists explored if matter and antimatter interact similarly with gravity. According to Einstein’s weak equivalence principal matter and antimatter should interact similarly with gravity. The new research has shown that antimatter does respond to gravity in the same way as matter.
This research paper has been published in Nature. The new finding has come from examining the charge-to-mass ratios of protons and antiprotons. This can help to determine the key difference between the two.
Scientists confined antiprotons and negatively charged hydrogen ions, to make the measurements. They have used this as a proxy for protons. They used a Penning trap where a particle follows a cyclical trajectory with a frequency. This frequency is close to the cyclotron frequency. Then they feed antiprotons and negatively charged hydrogen ions into the trap. Then they measured the cyclotron frequencies of the two particle types one at a time. They have compared their charge-to-mass ratios.
The team used the measurements to test a fundamental physics law which they call weak equivalence principle. In this principal, different bodies in the same gravitational field needs to go through the same acceleration in the absence of frictional forces. This experiment was placed on the surface of the Earth. The proton and antiproton cyclotron-frequency were measured in the gravitational field on the Earth’s surface. Difference between the gravitational interaction of protons and antiprotons will create a difference between the cyclotron frequencies.
The scientists found out matter and antimatter responded to gravity in the same way by using the gravitational field of the Earth as the planet orbited the Sun.