(Contribution from Dr. Towell)
I’ve always been amazed when two things that are extremely different have so much in common. While examples are abundant, I’d like to highlight two.
Example one: Our sun and the state of matter created in the collision of gold nuclei traveling at almost the speed of light. Both of these are sometimes loosely referred to as ‘fireballs’ because they are hot and round. Studying these objects helps us learn more about how the basic forces in nature work and how matter is structured. Of course studying these objects, especially the inside of these objects is extremely difficult. So these two objects have lots in common.
If you’d like to know a bit more about the core of the collision of nuclei, check out this story. We call this state of matter a quark-gluon plasma or QGP.
On the other hand, these objects are worlds apart. The core of the sun is hot, about 16 million degrees. The core of the collision of nuclei is 250,000 times hotter. That means the QGP is about 4 trillion degrees. There is also a size difference. The sun is about 1,400,000,000 meters in diameter. The QGP formed in the collision of gold nuclei is about 0.000 000 000 000 001 meters in diameter. That’s right. The sun is about 1,000,000,000,000,000,000,000,000 times bigger than the QGP. I don’t even know the name of that number.
So how do we study something as small and as hot as the QGP? We build big detectors and study the particles that are emitted from it. Again, this is similar to studying the sun since we don’t have the option of getting close to or inside of it either. So we study the sun by viewing the particles it emits. More »