Cari Cesarotti

Yeah, so this is a great question. And every time, certainly as a PhD student, when I listen to it, I would hear someone describe one machine and be like, well, this is the best collider. And then I would hear someone describe the other one. I'm like, no, this is the best collider. And the answer is they both have strengths.

Yeah, so this is a great question. And every time, certainly as a PhD student, when I listen to it, I would hear someone describe one machine and be like, well, this is the best collider. And then I would hear someone describe the other one. I'm like, no, this is the best collider. And the answer is they both have strengths.

So when you collide something like an electron, you're basically just colliding electrons. It's a fundamental particle. So electron plus electron combines. Usually we do particles and antiparticles. So you have E plus, E minus come in, collide, produce a charge neutral state.

So when you collide something like an electron, you're basically just colliding electrons. It's a fundamental particle. So electron plus electron combines. Usually we do particles and antiparticles. So you have E plus, E minus come in, collide, produce a charge neutral state.

And all of the energy of these two electrons colliding can be recombined into different massive particles, different momentum particles, as long as the net energy and momentum of the event is conserved. However, for proton-protons, protons are actually a big bag of stuff.

And all of the energy of these two electrons colliding can be recombined into different massive particles, different momentum particles, as long as the net energy and momentum of the event is conserved. However, for proton-protons, protons are actually a big bag of stuff.

And that bag includes the three quarks that usually we talk about when you first take your nuclear physics course or whatever in school, right? I don't know if many schools have nuclear physics, but chemistry, let's say chemistry. You have up and down quarks, basically are the primary constituents of protons at low energies. But these quarks are tied together with gluons.

And that bag includes the three quarks that usually we talk about when you first take your nuclear physics course or whatever in school, right? I don't know if many schools have nuclear physics, but chemistry, let's say chemistry. You have up and down quarks, basically are the primary constituents of protons at low energies. But these quarks are tied together with gluons.

And inside the quarks, or sorry, inside the protons, especially as you start cranking these things up to really high energies, is the bag becomes much more complicated. And inside these protons, we have particles that are very cleverly named as partons because they are parts. And particles have to end in on. So partons.

And inside the quarks, or sorry, inside the protons, especially as you start cranking these things up to really high energies, is the bag becomes much more complicated. And inside these protons, we have particles that are very cleverly named as partons because they are parts. And particles have to end in on. So partons.

Yes.

Yes.

He did enough good things, so we can give him a break for this one. But inside this proton, all of these different partons, which include the gluons, which are those bosons that we talked about earlier, and the quarks, they kind of share the total energy of the proton. So at the LHC, we collide protons of 7-ish TeV. And no one particle inside that proton is going to have anywhere near 7 TeV.

He did enough good things, so we can give him a break for this one. But inside this proton, all of these different partons, which include the gluons, which are those bosons that we talked about earlier, and the quarks, they kind of share the total energy of the proton. So at the LHC, we collide protons of 7-ish TeV. And no one particle inside that proton is going to have anywhere near 7 TeV.

tends to happen that the gluons take most of the energy and then quarks also take some of the energy. So when you're really looking at a collision, it's a gluon-gluon collision or a quark-quark collision. Or even in the proton, sometimes you can have quark-antiquark pairs pop into the vacuum or pop out of the vacuum and then disappear again. And sometimes you can collide those.

tends to happen that the gluons take most of the energy and then quarks also take some of the energy. So when you're really looking at a collision, it's a gluon-gluon collision or a quark-quark collision. Or even in the proton, sometimes you can have quark-antiquark pairs pop into the vacuum or pop out of the vacuum and then disappear again. And sometimes you can collide those.

So you can have a quark-antiquark interaction. And all of these things will share the energy of the proton. So in some ways, that makes for a super interesting collider because the opportunities of what kind of particles you can collide is much bigger, right? You can collide not only up and down quarks, but strange quarks or charm quarks or gluons and some things more rare than others, of course.

So you can have a quark-antiquark interaction. And all of these things will share the energy of the proton. So in some ways, that makes for a super interesting collider because the opportunities of what kind of particles you can collide is much bigger, right? You can collide not only up and down quarks, but strange quarks or charm quarks or gluons and some things more rare than others, of course.

But it means that you can see all sorts of interesting signatures come out. The downside is that you never know exactly what the energy of these things are. So that can make your analysis much, much harder. And of course, you don't get that full energy of the protons. So even though the LHC runs at 14 TeV, we don't actually get to see any collision happen at 14 TeV.

But it means that you can see all sorts of interesting signatures come out. The downside is that you never know exactly what the energy of these things are. So that can make your analysis much, much harder. And of course, you don't get that full energy of the protons. So even though the LHC runs at 14 TeV, we don't actually get to see any collision happen at 14 TeV.