Questions tagged [strong-force]
The strong force or interaction is responsible for the confinement of quarks inside hadrons and the binding of nucleons inside a nucleon, and it is described by the gauge theory of QCD. It provides most of the mass of ordinary matter, which is dominated by the nucleons, proton and neutron: over 99% of the mass of these is attributable to the strong-force field energy. Use where technical details of QCD are not warranted.
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How does strong nuclear force hold hydrogen vs xenon? does the strong nuclear force have variable distance? [closed]
My understanding is that the strong nuclear force holds the protons and neutrons together as well as the surrounding electrons. give too many electrons and it becomes an unstable isotope due to ...
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Can a $\phi$ meson decay into a pair of charged pions ($\pi^-$ and $\pi^+$)?
I understand that $\phi^0 \to \pi^+ \pi^- \pi^0$ is OZI suppressed.
But how about $\phi^0 \to \pi^+ \pi^-$?
Wikipedia doesn't list this decay path but $\phi^0 \to K^+ K^-$. Why? $\phi^0$ is a mixing ...
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EM force or Strong force?
$$
e^- + p \rightarrow \Delta^{++} + e^- + \pi^-
$$
Apparently this reaction is mediated by the EM force. My question is: how do you know it isn't the strong force?
Yes, all the particles have ...
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How relationship between the Euler beta function and the strong nuclear force can be mathmatically be proved?
I'm Korean highschool student and was writing a report about Euler beta function and string theory. And I can know find that Euler beta function is similar with the strong nuclear force equation. But ...
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Why is the mutiplication table for generators in the $su(3)$ algebra so bizarre?
The square of the Gell-Mann matrices $\lambda_1$, $\lambda_2$, and $\lambda_3$ has the bizarre value $2/3 * I + \lambda_8 / \sqrt{3}$.
Is there a simple way to deduce the result from the fact that $\...
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Equation to predict stability, half-life and decay products of atomic nuclei?
Given an atomic nuclei say C-14 or U-233 or anything in-between or outside the range and given the ratio of protons and neutrons in the nuclei, is there a comprehensive equation or set of equations ...
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Is there any something something force other than the electro magnetic force?
Far as I can tell, the force generated by electromagnetic field can be seen as an electrical force or as a magnetic force depending on the observer, i.e., these forces are actually the same phenomenon ...
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Why are nuclei with large numbers of neutrons only stable with correspondingly large numbers of protons? [duplicate]
Large numbers of protons need to be separated by neutrons, otherwise they repel....
But why do nuclei with large of numbers of neutrons only remain stable with a relatively, correspondingly large ...
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Why did Yukawa theorize a neutral pion? Was it necessary or a guess?
At the time, neutrons had just been discovered, but were only needed to explain the extra mass inside nuclei...
We now know that the strong force isn't strong enough to hold positive protons together ...
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Why protons and neutrons don't have less mass than their constituents?
A system of gravitational attracted objects weight less than the sum of their individual masses because it needs energy to move them apart and overcome the gravitational attraction. Same is true for ...
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Strong $CP$ problem and fine tuning
I have worked my way up to and through Srednicki's Quantum Field Theory chapter 94 and was also doing some reading on the internet about the strong $CP$ problem.
Wikipedia's entry on the strong $CP$ ...
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What causes the difference in ranges of forces?
What causes the difference in ranges of forces? In other words, why is it that the weak force acts only at small distances whereas the Coulomb force has a very large range?
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What quantities are associated with the strong and weak forces?
If mass is the quantity associated with gravitation, and charge is the quantity associated with the electromagnetic force, what quantities are associated with the strong and weak forces?
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Do Neutron stars have free quarks?
Do Neutron stars have free quarks? Also Can Quark Stars be formed also due to this reason?
Because of Asymptotic freedom high energy causes quarks to be free but according to the mass-energy ...
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Why would the ratio of the strong nuclear force to electromagnetism be about 137 to 1? What does the fine structure constant have to do with it? [closed]
Is it just another weird coincidence that the strong force is approximately 137 times as strong (at appropriate distances) as the EM force?
Also, when comparing the four fundamental forces and their ...
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How scientists know which particle is/is not influenced by strong force?
Muon is said to be uninfluenced by strong force, unlike pion.
My question is, based on which experiment, scientists determine a particle is influenced by strong force or not?
Edited:
Thank you for the ...
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What is the Wood-Saxon potential for hydrogen-1 nuclei?
I’m trying to calculate the distance within which the strong interaction between two H-1 nuclei is stronger than the electrostatic force repelling them, thus triggering fusion.
Doing so by setting the ...
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What is the actual carrier of the strong force? [duplicate]
I have been digging into the particle physics recently and I have found two different answers for this question. First of all, according to Wikipedia the Pion is a meson that acts as the carrier ...
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What happens inside a proton?
This post contains 3 questions but they are very similar.
I saw from this question What's inside a proton? and other websites that protons aren't really made up of three quarks, but a lot of ...
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How do we know that the repulsion between nucleons at small degrees of seperation is caused by the strong nuclear force and not any other force?
I've read that at seperations of less than 0.7 fm the strong nuclear force becomes repulsive as evidenced by the nucleus not collapsing in on itself. How do we know this repulsion is caused by the ...
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Is there an energy release from gluon expansion and contraction?
When an electron drops to a lower orbit, energy is released as a photon. Gluons expand and contract in-between quarks, described like springs or rubber bands that have tremendous force when extended ...
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How the non-existance of free quarks is explained by asymptotic freedom?
It is written in page 527 of Schwartz Quantum Field Theory and the Standard Model book that
Due to asymptotic freedom, free quarks do not exist.
I don't understand how asymptotic freedom explains ...
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Glue vs spring, the approach
Why does quantum mechanics use the term "glue" instead of "spring"? Is the strong force wchich keeps quarks together so different from the behavior of springs that they must have a ...
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Are gluon particles analogous to flux tubes?
I've always been told gluons are the force "particles" mediating the strong force. And I've learned that Fluxtubes are what hold quarks together. Are these fluxtubes the "particle" ...
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Do gluons interact via virtual photons?
On a video on Youtube, I commented how a PBS Space Time episode helped me understand the speed of light by calling it the speed of causality. In response, I received the following comment:
"Let'...
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Do pions not interact with other pions via the strong force?
Imagine a positive and negative pion, their only interaction between each other would be due to electromagnetism and the weak force, right? It is not like these two pions can form neutral pions due to ...
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„Orbital“ of an quark
Inspired by the idea of the electron orbitals ( probability of finding an electron in an atom) i was wondering what that would look like inside a proton or neutron for quarks. For simplicity consider ...
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How do mesons explain nuclear stability?
I understand that nuclear stability is explained by the presence of the residual nuclear force, which in turn is a result of the strong nuclear force, which I believe, is mediated between quarks via ...
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Would two helical magnetic fields attract stronger than two normal dipole magnets?
We know that we can artificially manipulate magnetic flux in space combining different discrete magnetic sources to create complex magnetostatic fields on air like chiral magnets or even helical ...
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Is the strong force a historical accident? [closed]
This is a history-of-physics question.
The atom was discovered to have a nucleus, a very small core with a positive charge. Then all atoms were found to have roughly multiples of the charge of the ...
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Are there workable alternative ways to visualize the strong force?
Background
Same electric charges always repel each other, without exception.
Opposite charges always attract.
An atomic nucleus with multiple positive charges must therefore generate tremendous forces ...
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Why spin-aligned nucleons bind stronger together [duplicate]
Protons bind to neutrons only if their spin is parallel to each other. Is there an easy explanation for this? What force is responsable for this spin dependence?
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Is the gluon also a repulsive force?
In the picture of a proton we see 3 quarks, held together by gluons. But the two $u$ quarks repel each other , so the gluons act through the strong force, whereas the $u$ and $d$ quarks attract each ...
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Why doesn't a nucleus-like body made up of just neutrons exist?
We know that neutrons exert short ranged nuclear forces over other nucleons in a nucleus, and these forces are only attractive in nature. Also this force is universal and doesn't differentiate between ...
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Why did the quark epoch occur earlier than the lepton epoch?
I don't understand the reason and hypothesis behind why the quarks appeared first—as per the big bang cosmology—shortly after the strong and electroweak force separated. We don't know what the quarks ...
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Non-relativistic quark model, baryon masses and potential
Is there a simple non-relativistic quark model, based on which baryon masses, especially for the nucleon and the Delta resonance can be calculated?
What is a reasonable non-relativistic potential? Is ...
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On $\Delta^{+}$ particle decay
Using isospin notation
$$
\Delta^+=\left|\frac 3 2,\frac 1 2\right\rangle=\frac{1}{\!\sqrt{3}}\bigg(|duu\rangle+|udu\rangle+|uud\rangle\!\bigg)
$$
It is known all of the $\Delta$ baryons with mass ...
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Does the energy of the strong force have mass? [closed]
The mass of a proton is said to predominantly be "comprised" of the mass of the strong force interactions within the proton. Logically, one could conclude that the energy (the strong force ...
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Strength of strong force and electromagnetic force
In this link, it is claimed that the strength of the strong force w.r.t. the E&M force is about 137 times larger. Does this have anything to do with the fine structure constant?
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If isospin is conserved in a given strong interaction, can we say that the interaction is certainly allowed?
If isospin is conserved in a given strong interaction, can we say that it is certainly allowed and it's not needed to check other conservation rules like baryon number, electric charge etc. ?
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How did Ernest Sternglass’ phenomenologically incorrect model of the neutral pion predict its mass and lifetime so accurately?
In 1961, Ernest Sternglass published a paper where, using what seems to be to be a combination of relativistic kinematics and Bohr’s old quantisation procedure, he looked at the energy levels of a set ...
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What would happen in a hypothetical universe without the other forces other than gravity? [closed]
What would be the rules of a hypothetical universe where there is only gravitational force, and weak strong and EM force do not exist? What would be the consequences of that?
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Strong nuclear force in fusion
I have read that there is an increase in the amount of the binding energy from the reactant nuclei and the product nucleus during nuclear fusion and this causes the decrease the internal energy (...
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Cause of Strong force
What is the origin and cause of the strong interaction which occurs between the nucleons? I have read that it is caused by the exchange of mesons but what then ultimately causes this meson exchange to ...
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Nuclear FISSION origin
Neutrons and protons consist of quarks, and when a neutron and a proton are squeezed tightly enough together, the quarks in each begin to interact and cause them to attract one another. The resulting ...
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Is $SU(3)$ (and not $U(3)$) the symmetry group of color interactions because $U(1)$ is already used for EM?
I have already seen this question. It was answered that $U(3)$ can be decomposed into $SU(3) \times U(1)$, and $U(1)$ is already used for the EM interaction. Still, I wonder why the EM interaction ...
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Why is there no stable nucleus with two or more neutrons but no protons? [duplicate]
Why is there no stable nucleus with two or more neutrons but no protons?
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Why we do not get naturally occurring elements with atomic number greater than 92? [duplicate]
Why we do not get naturally occurring elements with atomic number greater than 92?
I know that some arguments suggests that the reason is that all the elements with atomic number from 93 are highly ...
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What percentage of a Proton's mass is potential/kinetic energy?
So in an hydrogen atom, the total mass of the atom is equal to the masses of the proton, the electron, minus their net binding energy of around 13 eV. Making the total less massive than the sum of its ...
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Do all hadrons experience the strong nuclear force?
In nuclear physics, nuclear force, also known as the residual strong force, is mediated by pions exchanged between protons and neutrons. It doesn't seem like this should be limited to protons and ...
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