Antimatter…This strange stuff is an uncommon thing in physics which gained attention of many. It’s the matter that makes up our universe. It’s constituents are so small that they work with the forces of nature to make up everything in this world. But here comes the entry of another hero… “Antimatter”.
Antimatter is mainly composed of anti-particles (antiprotons, antineutrons and antielectrons). In short, you can call it as an anti-version of matter. They resemble their corresponding matter particles in all ways. Anti-matter has same mass of their twins but the only thing that makes up the difference is the charge and the spin. Anti-matter carries the electric charge opposite to that of matter and they spin differently. For example, a proton is electrically positive whereas an anti-proton is electrically negative.
The Missing Stuff:
This mysterious thing is extinct today. But many scientists think that equal amounts of both kinds (matter and antimatter) were created in the Big Bang at the birth of the universe, some 14 billion years ago… However within a fraction of second most of the antimatter had disappeared.
Why did it happen so? And where is this anti-matter?
Nobody really knew where this antimatter had disappeared. One explanation for this is the Annihilation process where destruction of both ordinary particles (matter) and antiparticles (antimatter) takes place as they collide with each other releasing a large amount of energy in return.
So when matter collided with the antimatter, there was some left over matter left after the annihilation process, which gave birth to the universe comprising mainly of matter. So this concludes that there was an imperfect balance. If an even balance had continued to persist after the Big Bang, then the Universe would never have come into being.
Is Antimatter Anti-gravity??
“What goes up must come down”, the gravitational formula for matter. But things might seem to work in a different way for antimatter. In case of mass we saw that the antimatter behaves the same way as their twin but do same laws of gravity apply to antimatter? Scientists also scratch their heads over whether antimatter would fall up or down.
In the Universe, antimatter particles are thought to exist mainly around black holes and in cosmic rays. Though it existed some 14 billion years ago it is rare today and scientists who wish to study antimatter particles have to manufacture them.
The only way to find out for sure is to test gravity’s effect on antimatter directly and a CERN(the European Organization for Nuclear Research in Geneva, Switzerland) based experiment has taken the first step in investigating it.That’s where ALPHA(Antihydrogen Laser Physics Apparatus) comes in.
The experiment includes manufacturing & trapping anti-hydrogen atoms. The anti-hydrogen atoms are created by combining single antiproton with one antielectron (positron). When the magnets are turned off, the anti-atoms are found to fall out of the trap. A highly sensitive detector is used to track the anti-atoms & it also records where the anti-atoms first come in contact with matter and annihilate.
By analyzing where the atoms hit & with what velocity, it is possible to find out whether the gravity acted on anti-hydrogen. If gravity acted on the anti-particle then it could fall at the bottom of the tube.
One of the physicists doing experiment at CERN , Joel Fajans, reported that while performing the experiment they found out that gravity has very little effect on the anti-atoms and they were found to move in a fast manner that they were barely affected by gravity. 411 atoms on 434 anti-atoms were seen to be energetic that they escaped from the trap of gravity. However accurate conclusions cannot be drawn from this experiment.
Fajans predicts that ALPHA may be able to answer the question of whether or not antimatter falls upward in the next four years or soon. Two more experiments at CERN, named AEGIS and GBAR, are also in the works with the primary goal of researching gravity and antimatter.
How this little particle disappeared in nature still remains to be mystery. Expected to hear a lot more about this little particle in the upcoming years! Finger’s crossed.