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Three quarks for Muster Mark*! And for every proton and neutron, too… right? 

Not so fast. You might have learned that every proton and neutron is made of elementary particles called quarks, and that each of the familiar subatomic bits that make up the nucleus of atoms is built out of precisely three of the quirky, quarky sub-subatomic bunch. 

This great video from The Physics Girl explains why that idea doesn’t quite add up to what’s really going on at matter’s smallest scales. Plus, CANDY! I love candy! Just wait ‘til you get to the part about how much mass is inside of a proton compared to the number of particles. Mind = blown, Einstein. 

*Funny historical note: At the beginning of the video, Dianna asks why “quark” is spelled the way it is. It looks like it should be pronounced “kwahrk,” but we clearly pronounce it “kwork”. Well, Murray Gell-Mann, the physicist who first theorized the existence of these elementary particles, had already picked out the name he wanted, a made-up word that he pronounced “kwork”, but with no idea how he should spell it. Then, while reading Finnegan’s Wake by James Joyce, he stumbled on the following passage:

Three quarks for Muster Mark!
Sure he has not got much of a bark
And sure any he has it’s all beside the mark.

Gell-Mann stuck to his guns on the “kwork” pronunciation, despite the fact that it’s obviously supposed to rhyme with “Mark”, but seeing that Joyce had stumbled upon the same rule of three quarks that the universe had, he couldn’t pass it up. Quantum literature!

Syracuse physicists confirm existence of rare pentaquarks discovery

Physicists in Syracuse University’s College of Arts and Sciences have confirmed the existence of two rare pentaquark states. Their discovery, which has taken place at the CERN Large Hadron Collider (LHC) in Geneva, Switzerland, is said to have major implications for the study of the structure of matter.

It also puts to rest a 51-year-old mystery, in which American physicist Murray Gell-Mann famously posited the existence of fundamental subatomic constituents called quarks, which form particles such as protons. In 1964, he said that, in addition to a constituent with three quarks, there could be one with four quarks and an anti-quark, known as a “pentaquark.” Until now, the search for pentaquarks has been fruitless.

“The statistical evidence of these new pentatquark states is beyond question,” says Sheldon Stone, Distinguished Professor of Physics, who helped engineer the discovery. “Although some positive evidence was reported around 10 years ago, those results have been thoroughly debunked. Since then, the LHCb [Large Hadron Collider beauty] collaboration has been particularly deliberate in its study.”

In addition to Stone, the research team includes other physicists with ties to Syracuse: Tomasz Skwarnicki, professor of physics; Nathan Jurik G'16, a Ph.D. student; and Liming Zhang, a former University research associate who is now an associate professor at Tsinghua University in Beijing, China.

Liming, in fact, is presenting the findings at a LHCb workshop on Wednesday, July 22, at CERN.

Stone credits Gell-Mann, a Nobel Prize-winning scientist who spent much of his career at Caltech, for postulating the existence of quarks, which are fractionally charged objects that make up matter. “He predicted that strongly interacting particles [hadrons] are formed from quark-antiquark pairs [mesons] or from three quarks [baryons],” Stone says. “This classification scheme, which has grown to encompass hadrons with four and five quarks, underscores the Standard Model, which explains the physical make-up of the Universe.”

Stone says that, while his team’s discovery is remarkable, it still begs many questions. One of them is the issue of how quarks bind together. The traditional answer has been a residual nuclear force, approximately 10 million times stronger than the chemical binding in atoms.

But not all bindings are created equal, Skwarnicki says. “Quarks may be tightly bound or loosely bound in a meson-baryon molecule,” he explains. “The color-neutral meson and baryon feel a residual strong force [that is] similar to the one binding nucleons to form nuclei.”

Adds Stone: “The theory of strong interactions is the only strongly coupled theory we have. It is particularly important for us to understand, as it not only describes normal matter, but also serves as a precursor for future theories.”

The discovery is the latest in a string of successes for Syracuse’s Department of Physics, which made international headlines last year, when Skwarnicki helped prove the existence of a meson named Z(4430), with two quarks and two antiquarks.

Much of this cutting-edge work occurs at CERN, where Stone oversees more than a dozen Syracuse researchers. CERN houses four multinational experiments, each with its own detector for collecting data from the LHC particle accelerator.

IMAGE….Syracuse University Professors Sheldon Stone and Tomasz Skwarnicki, doctoral student Nathan Jurik and former University research associate Liming Zhang are on the team that has confirmed the existence of two rare pentaquark states Credit Courtesy of CERN

For me, the study of these laws is inseparable from a love of Nature in all its manifestations. The beauty of the basic laws of natural science, as revealed in the study of particles and of the cosmos, is allied to the litheness of a merganser diving in a pure Swedish lake, or the grace of a dolphin leaving shining trails at night in the Gulf of California.
— 

Murray Gell-Mann

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Particles and Matter

According to the Standard Model, ordinary matter is made of fermions, or rather, by the first-generation fermion particles, namely, electrons and up and down quarks, which make up protons and neutrons in various combinations (approximately, a proton is made by the combination u-u-d, while a neutron by the combination u-d-d). The particles of the second and third generations have a larger mass, so they are highly unstable and can only be produced in the laboratory.

I’m not quite clear on the last part of the ask. Quarks are indeed researched through smashing, but their existence was first hypothesized theoretically by Murray Gell-Mann and George Zweig in 1964. Then the hypothesis was confirmed at the end of the sixties from studies conducted at the Stanford Linear Accelerator Center (SLAC ). When high energy electrons were fired at protons and neutrons –analyzing the energy and angular distribution of electrons– they observed that some of these electrons were bumping into electrically charged, point-like objects contained inside protons and neutrons, proving in this way quarks’ existence. 

So, the atom is not the smallest particle, but the use of subatomic particles makes sense only in nuclear physics. The other physical and chemical processes make sense at the atomic level and, in fact, the atom is now defined as the smallest unit of an element that retains all the element’s properties.

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Asked by whovians-in-purgatory 

Today the network of relationships linking the human race to itself and to the rest of the biosphere is so complex that all aspects affect all others to an extraordinary degree. Someone should be studying the whole system, however crudely that has to be done, because no gluing together of partial studies of a complex nonlinear system can give a good idea of the behavior of the whole.
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Murray Gell-Mann

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Probabilities, Possibilities and chance outcomes

“And someday, we may actually figure out the fundamental unified theory of the particles and forces, what I call the "fundamental law.” We may not even be terribly far from it. But even if we don’t run across it in our lifetimes, we can still think there is one out there, and we’re just trying to get closer and closer to it. I think that’s the main point to be made. We express these things mathematically. And when the mathematics is very simple – when in terms of some mathematical notation, you can write the theory in a very brief space, without a lot of complication – that’s essentially what we mean by beauty or elegance.

Here’s what I was saying about the laws. They’re really there. Newton certainly believed that. And he said, here, “It is the business of natural philosophy to find out those laws.” The basic law, let’s say – here’s an assumption. The assumption is that the basic law really takes the form of a unified theory of all the particles. Now, some people call that a theory of everything. That’s wrong, because the theory is quantum mechanical. And I won’t go into a lot of stuff about quantum mechanics and what it’s like, and so on. You’ve heard a lot of wrong things about it anyway. (Laughter). There are even movies about it with a lot of wrong stuff.

But the main thing here is that it predicts probabilities. Now, sometimes those probabilities are near certainties. And in a lot of familiar cases, they of course are. But other times they’re not, and you have only probabilities for different outcomes. So what that means is that the history of the universe is not determined just by the fundamental law. It’s the fundamental law and this incredibly long series of accidents, or chance outcomes, that are there in addition.

And the fundamental theory doesn’t include those chance outcomes; they are in addition. So it’s not a theory of everything. And in fact, a huge amount of the information in the universe around us comes from those accidents, and not just from the fundamental laws. Now, it’s often said that getting closer and closer to the fundamental laws by examining phenomena at low energies, and then higher energies, and then higher energies, or short distances, and then shorter distances, and then still shorter distances, and so on, is like peeling the skin of an onion. And we keep doing that, and build more powerful machines, accelerators for particles. We look deeper and deeper into the structure of particles, and in that way we get probably closer and closer to this fundamental law.“

Murray Gell-Mann