CERN Accelerating science

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What Happens When Matter and Antimatter Meet?

Matter and antimatter, or we should probably say particles and antiparticles, don't seem to like each other very much.
If they get too close, they destroy each other, disappearing in a kind of explosion.

Or may be it's the opposite: they like each other so much that when they finally meet, it's just an explosion of joy!

One way or the other (I guess we will never know), but there is definitely something "hot" going on: both particle and antiparticle disappear, leaving behind the energy they were made of.
Physicists call this "annihilation".

We can think back to our "playdough" example: we cut out a star, and its "negative image" appeared in the dough. If we now put the star back in its "negative image " hole, there are no more stars, and all our original dough (=energy) is back!