Do you like riddles? Try this one:
Once, more than 13 billion years ago, I filled the entire universe…but I lasted less than a second. Since then, I never existed again…until 2010. What am I?
How about this one:
I am 100,000 times hotter than the center of the Sun but I haven’t boiled yet; I’m still a liquid. What am I?
Or this one:
I am heavier (denser) than anything in the universe except a black hole but I flow 20 times more smoothly and easily than water. What am I?
Hint: the answer to all three riddles is the same.
Give up? It’s Quark Soup!
What’s Quark Soup?
All of the objects in our world are made up of atoms. Each atom is made up of a nucleus and a bunch of electrons (ok, at least one electron) surrounding that nucleus.
The nucleus of an atom is made up of protons and neutrons and protons and neutrons are made up of quarks: 3 quarks for every proton and 3 quarks for every neutron.
Quarks stick together. They are held together by a very strong kind of superglue called a “gluon” (glue-on, get it?). But gluons work differently from any glue you’ve ever used. When the quarks are just hanging out peacefully inside a proton or neutron, the gluons don’t do much. But if one quark tries to break loose from the others, the gluons swing into action. They tug tightly on that quark so it can’t escape. The more the quark tries to pull away, the tighter the gluon tugs on it.
Gluons are so strong that there is no way for a quark to escape from the proton or neutron that’s trapped it…unless you heat it up to 4 trillion degrees (that’s 4,000,000,000,000 ̊C).
Only at that temperature (sometimes written 4 x 10¹², meaning 4 with 12 zeroes after it) can the quarks break the gluons’ grip. Then the quarks and the gluons just hang out together in a kind of soup, Quark Soup!
But there’s just one problem: where can you go to find such a high temperature? How about the center of the Sun? Nope, that’s only 40,000,000 ̊C – a frozen popsicle compared to the temperature we need. Turns out, there’s no place in the universe today with a temperature nearly hot enough to make Quark Soup.
So that’s the end of that, right? Not so fast! I said, “There’s no place in the universe today hot enough for Quark Soup.” But there was once. All you need to do to make Quark Soup is to travel back in time…ok, way back in time…all the way back to the very first second in the life of the universe. And then you’d still have to go back even further, back to just a fraction of a second after the universe began.
But the point is, you can do it! Unless, of course, you don’t own a time machine and can’t find a friend to lend you one. In that case, you would need to create the 4,000,000,000,000 ̊C temperature all by yourself.
Fortunately, it’s not all that hard…at least not on paper. All you need are the nuclei from 2 gold atoms, a long circular tube and some very, very strong magnets. Put the nuclei in the tube and use the magnets to make the nuclei move very quickly through the tube. When you get them going at a speed almost equal to the speed of light, just make them crash head-on into one another, and bang, you’ve got the temperature you need for Quark Soup: 4,000,000,000,000 ̊C.
At that moment, the quarks will break loose from the gluons, destroying the protons and neutrons that held them captive for so many billions of years. You’ll be a modern day Aladdin, freeing the quark genies from their proton and neutron lamps.
Turns out, in 2010, scientists did just that. They set quarks free and made Quark Soup for the first time in more than 13 billion years; and they did it right on Long Island, NY at a place called Brookhaven. They built something called a Relativistic Heavy Ion Collider (RHIC for short). Its circular tube is two miles long and it uses 1740 powerful magnets. That’s what it takes to get the gold nuclei moving at speeds close to the speed of light. But they did it!
So what’s this soup like, anyway? Well, for one thing, it’s hot, very very hot. 4 x 10¹² ̊C hot. But even at that temperature, Quark Soup doesn’t boil. It’s still a liquid, not a gas.
It’s a liquid, but boy does it pour. It pours at least 20 times more easily than ordinary tap water. I guess you could say that Quark Soup is super-slippery.
For another thing, it’s small. Two gold nuclei produce a very, very tiny drop of soup. Think of a box where each edge is about an inch long. Now split that box up into 10 smaller boxes. Then split one of those smaller boxes into 10 even smaller boxes and keep doing this until you’ve done it a total of 12 times. The box you’re left with is about the size of a single drop of Quark Soup.
But this tiny, tiny drop of Quark Soup weighs about 1,000 pounds…heavier (actually, the correct scientific term is “denser”) than anything else in the universe…except a black hole. If you had a drop of Quark Soup the size of a marble, it would weigh about 100 trillion pounds. That’s 100,000,000,000,000 pounds, sometimes written 10¹⁴, 1 with 14 zeroes after it.
So Quark Soup is the hottest, slipperiest, heaviest (except for black holes) thing in the universe. But what does it taste like? Who knows! A single sip would vaporize your body. So there’s no way to know what Quark Soup tastes like, unless of course you ask Bobby Flay.