What's inside a proton?

If you could slice open a proton, what would you find inside of it?

 

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You can only slice open a stable solid, like a watermelon or a cake. You can't slice open a bowl of soup or a water ballon or a campfire.

Deep inelastic scattering of electrons has show that protons have point-like charged constituents which result in hadronic collision products (mesons and baryons) upon collision. The rest mass of the products is greater than the rest mass of the proton + electron, so those collision products don't directly answer the question of what a proton is made of. ("Inelastic" refers in this case to the conversion of kinetic energy to matter.) However, it does indirectly answer that a proton is made of 3 spin-1/2 electrically charged parts held together by some force stronger and more complicated than electromagnetism. These experiments, started in 1968, confirmed the 1963 Quark Model and the 1965 predecessor to Quantum Chromodynamics both of which built on 1961's Eightfold-way. By 1973, the experimental and theoretical picture was well in accord.

So a proton is best described as the ground state of an up-up-down baryon. Both its macroscopic properties (mass, electrical charge, quantum statistics) and microscopic properties (collision products, scattering centers) are controlled by this description and in the decades since 1968 no one has observed results at odds with this description.

The three lightest quarks are up and down. Three of these can combine to form spin-1/2 bound states (p, n) or spin-3/2 states (Δ⁺⁺, Δ⁺, Δ⁰, Δ⁻). The proton happens to the least massive of all of these, with important consequences for the stability of macroscopic matter.

 

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The three lightest quarks are up, down and strange. I changed my discussion to talk about just the two lightest, but never edited the word "three."

 

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Thanks for your thorough explanation. How much of the mass of the proton is made up by these 3 quarks? Also, are the quarks that make up a proton different from those that make up a neutron? In what sense?

 

The "mass" of a quark is a problematic question much like the mass of your head is. If we try and weigh just your head, the connection to your body gets in the way of measurement. If we cut your head off, blood will rush out and what we weigh is not "your head" anymore. With quarks the situation is worse in that 1) quarks are confined to hadrons (mesons, baryons) and 2) quarks are confined to a small location, thus their uncertainty in momentum is high thus their rest mass is not clearly the right thing.

Because quarks have asymptotic freedom, we can use probe them with high power electrons and they act to first approximation as bare quarks. The experiment is complicated because we can't aim at individual quarks. The harder you smack them (renormalization scale parameter μ) the more free they seem. So around a smack of 2000 MeV, the up quark is estimated between 2-3 MeV and the down quark between 4.5 and 5.5 MeV. In contrast, the strange quark is between 90-100 MeV. We also see similar results from computer studies of the theory of quantum chromodynamics compared with the masses of various mesons. In 2010 a press release was made that this issue was "solved" by the computer method, but scientists are a hard bunch to convince by admittedly approximate methods.

Thus, only about 1% of the mass of proton is attributable to the rest masses of bare quarks (which in turn, in the standard model, is attributed to the coupling of those quarks to the Higgs field).

https://en.wikipedia.org/wiki/Current_quark
http://profmattstrassler.com/articles-and-posts/the-higgs-particle/the-higgs-faq-2-0/
http://profmattstrassler.com/articl...proton-anyway/checking-whats-inside-a-proton/
http://pdg.lbl.gov/2014/reviews/rpp2014-rev-quark-masses.pdf (see Figure 2)
http://pdg.lbl.gov/2014/listings/rpp2014-list-light-quarks.pdf
http://arxiv.org/abs/hep-ph/9708255

Alternately, one may try to describe the mass of a quark as the mass each quark contributes to a bound system, with motion, strong and electromagnetic effects intact. But that doesn't give you very concrete numbers because of the wild dynamical variation between various mesons and baryons. For example, a nucleon masses over 6.7 times the mass of a pion, but only has 1.5 times the number of constituent quarks. In contrast, the ratio of the masses of the omega baryon and the phi meson is closer to 1.6. And \(\frac{2 m(\Omega_{c}^{0})}{2 m(\phi) + m(J/\psi)} = \frac{ 2 \times 2695.2 }{ 2 \times 1019.461 + 3096.916 } \approx 1.05\). So for the heavier quarks, the model of attributing mass to the constituent quarks is not wholly unattractive. The problem is that there are many more baryons and mesons than just the combinatorics of a non-dynamical, non-quantum quark model would suggest. Dynamics are important and so is quantum mixing of state.

http://education.jlab.org/qa/particlemass_03.html

http://profmattstrassler.com/articl...the-structure-of-matter/protons-and-neutrons/

 

So motion creates mass? Is this because the particles are moving at the speed of light? E equaling MC2?

 

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Motion does not cause mass. The increase is the mass is from the energy.

 

So the motion creates the energy, and the energy creates the mass?

 

The motion adds to the kinetic energy, and the energy adds to the gravitational field.

 

So the kinetic energy creates gravity? How does it do this?

 

Did you read the links rpenner gave to you? It seems that your questions are answered in the links and go more into depth than you can get in a forum.

 

So how does kinetic energy create mass/gravity? It's a harmless question..

 

The components of the proton are 2 positrons and an electron. The quarks are parts of these components.
I have explained this all in my thread that was moved to pseudoscience. Don't expect to get any truth from
these liars, they don't seek for the truth, they deal with lies.

I have found out why the proton is 1835 times more massive than an electron. These people here could not
explain it without using the quark model of the nucleus. Maybe someone just invented his own physics when he invented the Higgs mechanism explaining the generation of mass.

 

http://www.universetoday.com/114617/a-fun-way-of-understanding-emc2/

 

reported>

 

The above post is pseudoscience and other threads by this turkey have already been shifted to the pseudoscience section.
The fairy tales by Hans Christain Anderson are far more believable.

 

Of course, but the mass of a proton is a fairly complicated and the rpenner answered the question quite well and proviced links with more information on the mass of a proton. I read them and learned quite a bit that I did not know.

 

Please do not post pseudoscience in the science section, this stuff is fairly difficult because it is not intuitive, so adding stuff you made up is a hindrance to the questioners understanding.

 

Twice.

 

What the heck, let's make it thrice...