Scientists at the Large Hadron Collider say they are getting some clues about where all the anti-matter went.
That is a big deal because scientists have long been trying to figure out why anti-matter seemed to disappear.
The answer may lie in the fact that scientists at CERN, the European Organization for Nuclear Research, which runs the Large Hadron Collider, say matter and anti-matter may decay differently.
At the beginning of the universe, there was an equal number of particles and anti-particles -- matter and anti-matter. These particles had opposite electric charges
It's believed that when matter and anti-matter collided, they turned back into energy. But if there is still matter in the world, what happened to those matter-busting collisions? Shouldn't an equal number of both kinds of matter have cancelled each out, leaving nothing behind?
However, everything we see in the universe -- from tiny frogs to trees, buildings and stars -- are made of matter. And scientists say there is very little anti-matter around.
Something tipped the balance. What process left us with matter but not anti-matter?
Now CERN physicists say they have a lead on what that was: decay.
CERN reported that when scientists there smashed protons together inside the underground collider, they have been able to create conditions similar to the period soon after the Big Bang. That means they have seen some anti-matter particles.
CERN said they discovered a subatomic particle, dubbed BOs, which decays unevenly into matter and anti-matter. The anti-matter part decays faster than the matter.
It is only the fourth subatomic particle known to exhibit such behavior, scientists noted.
"By studying subtle differences in the behavior of particle and antiparticles, experiments at the [Large Hadron Collider] are seeking to cast light on this dominance of matter over antimatter," CERN reported on Wednesday. "The results are based on the analysis of data collected by the experiment in 2011."
It's been a big month in the physics world. Early in April, CERN reported that a $2 billion device attached to the outside of the International Space Station has found particles that could be the building blocks of dark matter.
While the particles were collected in the Alpha Magnetic Spectrometer on the space station, CERN scientists have been collecting and analyzing the data which could be offering the first glimpse of dark matter -- mysterious and so-far elusive matter that is thought to make up a quarter of the universe.
Scientists know that dark matter, which neither emits nor absorbs light, is there because of its gravitational influence on the rest of the universe. Beyond that, they know little about what it is.
If scientists can understand dark matter, it could offer valuable clues as to how the Milky Way will evolve and whether the universe will stop expanding at some point or if it will expand until it collapses.
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