The following questions were recently asked on Quora.com, the question and answer site:
“Do neutrons and protons touch each other in the atomic nucleus? Do protons and neutrons collide? Do protons and neutrons touch?”
These are questions that seldom get asked and really should be asked more often.
The discovery of atomic nuclei (and protons) in 1911 and the neutron in 1932 (yes, some of that is less than 100 years old) combined with the previous discovery of electrons left us wondering how these “subatomic” particles were arranged.
Since the heavy, heavy, heavy nucleus was far smaller than the atom as a whole, the ps and ns had to be “in” there while the electrons were around and about. First it was assumed that the electrons orbited their nuclei, like tiny planets, supporting the “planetary model of the atom,” which had been imagined quite some time before. Shortly thereafter it was shown how any such orbits would result in the electrons spiraling down into the nuclei as the orbits were unstable. As I have said often enough, if it had been orbits and only orbits of tiny electrically-charged particles, the Book of Genesis would have been woefully short. It would have begun with “Let there be light . . .” and then the lights would have gone out.
The question at the heart of the questions above is, what was holding the protons, the ps, and the neutrons, the ns, so closely together? No known force was even close to being strong enough. So, a new force was postulated, the “strong nuclear force,” as it became known as, and its characteristics were determined by what it was able to do. And we were off and running using the model that had worked so often before.
But there is a problem here. It was a tiny problem called the mass defect. With the discovery of the neutron, lots of things started falling into place. The so-called “alpha particles” (remember alpha, beta, and gamma radiation from school?) were identified as being the nuclei of helium-4 atoms. Supposedly these alpha particles were made of two ps and two ns, but given the masses, m(p) = 1.00734u, m(n) = 1.00874u, m(α) = 4.0015u things don’t add up. The alpha particle is “missing” 0.0304u of mass. (The mass unit “u” being the atomic mass unit which is exactly one twelfth of the mass of a carbon-12 atom.) In other words, there isn’t enough mass there to account for the existence of two protons and two neutrons. We now know that this mass was converted into energy (E = mc2) when the four particles were fused together to make the alpha particle/helium-4 nucleus. Fusion energy is something we would like to master today as a source of energy to support our lives.
But people didn’t stop at that point and say, well if there isn’t enough mass to support the existence of those four particles, held together by a mysterious and really just conjectured new force, what else could it be?
In my mind it was a new single particle, for which we didn’t have to explain why the separate particles didn’t fly apart. The four had been fused, aka melted together, to make a single particle, with the same charge as the two protons had (charge is conserved) but not all of the mass of the four ingredient particles. Nuclei were made from protons and neutrons, not of protons and neutrons. Since the separate particles no longer existed, and would not unless enough mass-energy (and it is a lot, even if slightly less than 1% of the mass of the helium-4 nucleus) could be injected into those nuclei, there was no need of an explanatory force keeping them together.
Fast forward to today and we now know that protons and, by implication neutrons, have an internal composition. Inside them are quarks, gluons, and a veritable witches’ brew of other particles, and a soupcon of “mass-energy,” whatever the heck that is.
So, to address some other questions above:
Do neutrons and protons touch each other in the atomic nucleus? I would argue that they are not there to touch. If they were there, what does touch mean? Do the ps and ns have a rind or skin that defines where they start and stop? (If so, I haven’t heard of such a thing.)
Do protons and neutrons collide? Again, I don’t think they are there to collide with one another, but if they were, the answer must be yes. Above absolute zero, all particles are in a constant state of motion. Moving around in a confined space would meant they must collide, which brings up the question of why would they stay separated from one another and not merge. What keeps them being separated?
Do protons and neutrons touch? Again, I don’t think they are there to interact, but if they were, this is a key question: what would be touching what? These particles are as diffuse as clouds. Can clouds touch one another, without merging?
In the current model, the guts of the proton and neutrons are assumed to be held together by the strong nuclear force (using the mechanism promoted for such an attraction), so that brings up another question: If the guts of protons and neutrons are held together by the strong nuclear force, why would it also not hold together the new single particles, the nuclei, which would have all of the components of the various ps and ns all mixed together?
We should ask, what is keeping the protons and neutrons separate? They do not have a skin or rind to protect their insides. There are no repulsive forces keeping them from merging, at least to my knowledge. What?
OMG, Making Trump’s Tax Returns Public! It is an outrage!
Tags: Corporate Greed, corruption, hypocrisy, obscene wealth, Republicans, tax the rich, Trump's Tax Returns
No.
It is not.
These are government documents and citizens have a right to see those not marked Top Secret or above.
In an actual civilized country, Sweden, any citizen’s tax return can be acquired by any other Swedish citizen who goes to a local tax office, fills out a form, and pays a small fee (for duplication costs). In Sweden, all tax returns are public documents, as they basically are here, except in the minds of those who want to hide their crimes. Or who want to lie about how much they make or about how much wealth they have.
Think about it. We are asked by our government to fill out extensive forms to determine how much tax we should pay. Why would those forms be secret to all other taxpayers, who may be suspicious that fraud is occurring elsewhere in the system? The answer is short—they should not.
Oh, did you see where Trump wrote off a $70,000 “business” expense for “hair care”? Any claim of him being a good businessman should end at that fact right there.