Have you ever wondered how this world is going to end? Global warming? A massive earthquake? A huge meteor from out of space comes down and wipes us all out? What about a zombie apocalypse? But what if I told you could literally end this world, with the help of a mysterious particle? (cool right? or not-so-cool? You decide). Nevertheless, I think we can both agree that this sounds like some pretty crazy stuff! Now before I give you a tutorial on how to end the world, let’s try to understand how this is even possible in the first place.
For us to successfully carry out this mission, we will need to have a basic understanding of antimatter, which is essentially just the same as matter, except for a key property which is flipped: its electric charge. For every piece of matter that exists, there is an antimatter counterpart. Although matter and antimatter behave in exactly the same way, in the sense that they both experience gravitational forces to other forms of matter, have regular mass and obey Newton’s laws of motion.
Now here’s the fun part, when matter and antimatter come into contact — KABOOM! They annihilate each other and gamma radiation is given off. But before we use it to blow everything up, let’s have a look at how we’ve taken advantage of this effect.
Hospitals use positron-emission technology (PET) for imaging, for example, brains of patients with Alzheimer's disease or stroke patients. A positron is an antiparticle of the electron. When a positron-emission technology scanner is used, a positron-emitting isotope is injected into the patient. Each positron travels just a few millimetres before it comes in contact with an electron within the body and the positron and electron destroy each other. As a result, two gamma photons are produced and sensed by detectors connected to computers. Eventually, an image is formed from the signals from where the positron-emitting nuclei are located within the body.
Positron emission takes place when an unstable nucleus with too many protons changes into a neutron, emitting a positron in the process. Since a positron is the antiparticle of an electron, it carries a positive charge and is represented using the symbol: β + (or β +1). Additionally, a neutrino, ν, is emitted (no charge). The following diagram shows the changes that take place when an isotope, X, emits a positron and changes into Y (because the proton number has changed, the element changes from X to Y.) A and Z representing the mass number and the atomic number respectively.
Calculating how much antimatter we need
You’ve probably heard of Einstein’s famous equation: E = mc², and if you’ve done a little research on this equation, you’ll have discovered that energy is equivalent to matter and that they can both be converted to each other; that’s true, but it’s incomplete. For matter to be converted into energy, it must be combined with antimatter. So what Einstein’s equation really means is that energy can be converted to matter and antimatter, and that matter and antimatter can be combined together to become energy.
Now let’s take another look at this equation, the E stands for energy, m for mass, and c is used to represent the speed of light (c² is the speed of light squared). c² is actually a pretty number, like very big, it’s about 9 x 10¹⁶, that’s 9,000,000,000 km/s. This means that very little mass is needed to create a lot of energy.
Now all that is left for us to do is calculate how much mass of matter and antimatter we need to blow this planet up! Lucky for us, we already know the value of c², and thanks to some crazy scientist by the name of Scott Manely, we know that 2.25 x 10³² joules of energy is needed to wipe this planet off the face of this eart-… universe.
After some substitution and rearrangement, we can conclude that:
m = 2.25 x 10³² / 9 x 10¹⁶
and m is equal to… 2.5 trillion tons of antimatter. Well, that’s disappointing…That’s more than the weight of Mount Everest. Nevermind lads, I guess we’ll have to wait for God to destroy Earth himself.
Additional challenges we face
The fact that we need 2.5 trillion tons of antimatter isn’t the only challenge we face. Let’s visit CERN’S Antimatter Factory, the largest and most powerful antimatter production facility in the world.
It’s pretty obvious to us that antimatter can be very dangerous, but unfortunately (or fortunately), we can’t make enough antimatter for it to be dangerous. For the past 35 years, we’ve been working hard non-stop, to make as much as antimatter as possible. So how much antimatter does 35 years of tireless effort bring? Well, if we were able to gather and store all the antimatter ever made by us and combined them all together with the equivalent amount of matter, we’d have just enough energy to make ourself a hot meal or two. That’s obviously not a lot of energy, at all — and this fact is often used as the key argument against those who claim that mankind’s study of antimatter poses a threat to humanity.
Now, this last challenge is quite an interesting one. We believe that matter and antimatter are created in equal quantities from energy. When our universe was much younger billions of years ago, the energy available at the time, in theory, should’ve created equal amounts of matter and antimatter. Yet today, our universe consists solely of matter. Are we missing something? Is there something we are unaware of? Why is that our universe is made up of matter only? The simple answer to that question is, we don’t know. This is something scientists have been trying to figure out for decades and is one of the biggest mysteries of fundamental physics.
But worry not comrades! One day, we will uncover the mystery of the missing antimatter. But until then, keep working hard — and we will eventually, blow-up Earth *laughs evilly*