Scientists at the largest atom smasher in the world have captured a strange subatomic particle changing from matter into antimatter. This discovery could help us to understand how the universe survived annihilation so soon after its explosion.Researchers from Oxford University used data from the Large Hadron Collider's second run to identify the charm meson, a tiny particle that both contains a matter and antimatter version. This is the fundamental building block for matter, which transforms back and forth between them.Every particle has an antiparticle equivalent with the same mass and lifetime as it, but with a different charge. Photons (light particles) can have their own antiparticles, while others can exist simultaneously as matter and antimatter thanks to quantum superposition.Related: Beyond Higgs - 5 mysterious particles that lurk in the universeThis category includes the charm meson. Quantum superposition, which is a result of quantum mechanics, allows tiny particles to exist simultaneously in multiple states. These particles can then be observed and picked one state to land in. They are not just particles. Instead, they behave like tiny waves. The magnitude of these waves at any point in space represents the probability of finding one particle at that particular point.The charm meson (formerly D0) and its antiparticle counterpart, anti-D0, exist in superposition. When these waves overlap in different ways, D0 and anti–D0 form two matter particles, D1 and D2, both of which are also in superposition. D1 and D2 both contain the same antiparticle (anti D0) and particle (D0), ingredients, but they have slightly different combinations of each. This gives them different masses, and different lifetimes.It is also possible for D1 and D2 to superpose to create D0 or anti D0 depending on how they are combined."You can think of D0 as made of D1 or D2, or D1 is made of D0/anti-D0. It's just two different ways of looking at the exact same phenomenon," Chris Parkes (an experimental physicist at Manchester and spokesperson for the LHC), told Live Science.The mass of these particle waves determines their wavelength and, therefore, how they interact with one another. It is the difference between D1 and D2 in mass that determines how fast the charm meson switches between its matter and antimatter forms (anti-D0).This difference in mass is very small: 3.5x10 minus 40% ounces or 0.000000000000000000000000000000000000000001 kilosResearchers measured 30.6 million charm mesons after two protons were melted together in the LHC. This was to make it possible to measure this exact. Charm mesons travel only a fraction of an indian before they become lighter particles. However, the ultra-precise detectors within the particle accelerator allowed the team to compare those charm mesons that traveled farthest and those that traveled the least distance. This difference was used by the researchers to determine the mass difference between the two states.This is the second instance of a particle being caught oscillating between antimatter and matter in this manner, the first being the 2006 measurement of the strange beauty meson. The researchers said that it was difficult to spot this in the charm particle because the unstable particles usually decay before they can switch.Guy Wilkinson, an experimental scientist at the University of Oxford, stated in a statement that oscillation in the charm particle is "impressive" because, unlike beauty mesons, it is slow and therefore very difficult to measure in the time it takes for the meson to decay.Because particles that can leap between matter or antimatter are so important, they are at the heart of one of the greatest mysteries in science: Why the universe exists.The Standard Model is a theory that describes fundamental particles of the universe. It states that matter and antimatter were created equally by the Big Bang. The universe we live in, however, is almost entirely composed of matter. Because matter and antimatter are annihilated on contact, it is expected that the universe would have been destroyed as soon as it started. Then, what was the reason for the imbalance?There are some hypotheses that particles such as the charm meson may have saved the material universe. This is especially true if they change from antimatter into matter more often than the reverse. The upgrade to the LHC is due to turn back on in September, after it was shut down for over three years. Similar meson investigations are scheduled to be conducted by Japan's Belle II experiment. It is possible that further clues could be found.Researchers published their findings on June 7th on the arXiv preprint server. The study is still being peer-reviewed.Original publication on Live Science
