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Higgs Bosone

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The LHC is really all about discovery and exploration. We are looking for different kinds of things. New, crazy kinds of things. To make up everyday matter you only need an electron, up quark and a down quark. Cause with these, the upquark and downquark you can make a proton, or you can make a neutron. With electrons, protons and atoms, you can make any atom. So you only need these three, but there's... How many particles we discovered? Twelve? Why do we have them? I don't know. How many are there? A hundred? A million? Only twelve? We don't know. We are looking at the tip of the iceberg here and wondering... is there a huge iceberg under the water? Or is this it? And what does it mean in either way? Right? We are looking for patterns. It is just like periodic table.O You take all the elements, and you organize them by their characteristics.. An they fall into categories. And these guys over here tend to behave one way, and these guys tend to behave another way. WHY? Because of their fundemanetal underlying structure. Now we know it is because electrons orbit around nucleus. So we have a periodical table of the fundamental particles, And like periodic table we have been putting it together, and trying to organize by the characteristics of the particles. And it has some interesting features. It has patterns that suggest that there must be some sort of underlying structure that we don't understand, we haven't seen it yet. There are six quarks: up, down, charm, strange, top, bottom. These guys are called leptons. These are just names: electrons, muon, tau These guys interacting each other, these two interacting each other. these two interacting each other. Same way, these guys are all paired. Are there more here? We don't know. What is the source of patterns we see in this table? We don't know. We are trying to figure out clues, by seeing what other kinds of particles also exist. What is out there? The thing is, we have this collider and the magic of the collider is that you can make kinds of matter that you donit have around. You take two kinds of particles and annihilate them, and it is not like what comes out has to be a re-arrangement of what went in. It's a kind of quantum magic where it sort of disappears into pure energy, and then you can make any sort of particle for which you have enough energy. It's like you have a menu. You go to a restaurant, and you have a menu: I have this much energy..So I can make anything that costs that much energy or less. That's why you want to have as much energy as possible. And everytime you crank up the energy, you could be exploring a whole new energy range, whole new regime. It is like landing on a new planet, stock full of new particles that nobody has ever seen. Because nobody ever had the energy to make them. And as soon as we got over the threshold, boom they just pop out. And so one of the things people predict is the Higgs boson. The Higgs boson is the particle responsible gor giving mass to other particles. When you think of being having mass, it has "stuff" to it, it's not actually "stuff". Earlier I said particles have mass, but no volume. How could that be? Turns out the mass is probably just a characteristic of a particle they way, like charge is. Some particles have charge, some particles don't. It's just a different kind of charge. So you can take a mass\ sort of gravitational charge and two things that both have mass, attract each other. Interestingly you can't have negative mass or repulsive gravity. So gravity is different than other forces in that way. The Higgs theory starts with this: Imagine a field that permeates the entire universe. And every particle feels this field, is affected by this field, in different amounts. So\ some particles are really slowed down by interactions in this field, like swimming through molasses. and other particles hardly feel it. So, the ones that hardly feel it,they have a small mass. the ones that are really affected by it, or slowed down by it are the ones with a large mass. So you turn the question about why do particles have different masses into a different question: Why do particles feel the Higgs field differently? But there is one manifestation of this field, is the existence of a particle. There are lots of different reactions that can give you the Higgs. For example, you could have two gluons, when fused will give you a Higgs boson. and the Higgs decays into bottom quarks. The problem is, there's lots of other ways to make two bottom quarks. In fact it is one of the most common things to make. We expect that it'll happen million times more often from other kinds of processes, than from the Higgs. The thing is we can't see inside these reactions. We can't watch them, or reverse them All we can do is to see the reaction, decay products of the reaction. So, this part is all you really see, and what you want to know is this intermediate state exist? First the collusion happens, it lasts about 10 -23 seconds, and you get one measurement right. So if you say I am going to plot the mass of the total energy, add this guy and this guy together, and the total energy is here. So, the other axis here is the number of collusions, In an individual experiment you get one measurement, right? Here. Another one, you get another measurement. another one... Eventually you build up your data, and the data looks like this for example. And then you have two theories to predict the data. One says, well, I will predict there's no Higgs boson, so the data should follow this line. In the other I will predict there's a plausible Higgs boson, The problem is, the difference between these two theories is very small. and so it is very hard to distinguish these two with our data. because the predicted effect is tiny. If the predicted effect were huge, it would be very easy to tell the difference between with Higgs Boson or not with Higgs boson. But the predicted effect is tiny, and so it is really hard to see. What you really need is huge amount of data. You need to take a bazillion collusions, in order to see the difference. That's why we run this thing, 40 million times per second. all day, all year. to get a lot of collusions to tell small differences between these theories. It is like when you take a picture of the sky. YOu just take a picture, you got a little bit of light. The longer you leave your telescope looking at the sky, the more you can see farther away things. But there are lots of other things that make the Higgs There are ten other ways you can see the Higgs people are working on that one also. We work in a collaboration of thousands of people and there are people working on every single channel. Some people are working on this one, some people are working on this one, The idea is to look everywhere simultaneously, to see a little bit of evidence here, little bit of evidence there, and a little bit of evidence here, that can be combined to a convincing evidence. So we are going to be running it for a long time and hope something will pop out. There.s still possibility for a lot of new things. we have been running for a while, we haven;t seen anything crazy yet, but there could still be crazy pink elephants there waiting to pop out. That's why, anyday somebody could say, o wow, we see something excited. Everytime you open your email that could be the time your heard about Or everytime you make a plot, what's in the data, what's in the data? It's exciting.

Video Details

Duration: 7 minutes and 44 seconds
Country: United States
Language: English
Genre: None
Producer: PhD Comics
Director: Jorge Cham
Views: 1,508
Posted by: bluemouse on Jul 8, 2012

Thank goodness for this fantastic video from Jorge Cham of Ph.D. Comics and CERN physicist Daniel Whiteson. It does a great job explaining (a) what exactly the Higgs Boson is and (b) how it fits into the larger quest to understand the fundamental building blocks of matter.

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