Thread: Gravity in the Nucleus View Single Post
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Your reply here is laced with ignorance and mistakes, and you seem to somehow have the ability to state all of the statements below as IF you have a complete knowledge of what you are stating. Nowhere in the immediate quote below was even a question or any sense of uncertainty of what you are stating:

 Quote by Andrew Mason Gravity appears to be different than the other forces. Nothing in EM or the Standard Model accounts for gravity. Only General Relativity does that. The principle of equivalence says that gravity and inertia can be considered equivalent, so gravity can be looked at as a pseudo-force or a curvature in space time. There is no evidence that space-time has quantum-like discreteness, unlike EM phenomena and the nucleus. So there is no reason to believe that gravity is any different at small distances. EM theory assumes point charges but we know that the proton is not a point charge. According to the Standard Model, coulomb force is associated with the + and - 2/3 spin of quarks. The model does not explain how the coulomb force results from that and does not predict the nature of force that is created (perhaps my understanding of this is incorrect, in which case I would welcome correction). We don't really know where it begins. We only know that it is associated with quarks and exists in some region outside the proton, perhaps down to the quark level, perhaps not. Gravity, on the other hand, has no such limit because it is not so much a physical property of matter as it is a property of the space-time environment.
For someone who keeps insisting that all theories are subject to being challenged and being changed, you are quite arrogant in what you think gravitational theory should be and what it should not be. While GR has a number of verifications, in terms of degree of certainty, it has a LESS degree of certainty that classical E&M and QED. Now read that again - GR, which you are putting ALL your faith in, has a lower degree of certainty than classical E&M and QED. Furthermore, and pardon me for saying that, but I do not believe you even have a clue the complex theory of GR, much less are able to judge its validity.

Secondly, + and - 2/3 spin of quarks?!!!!

Thirdly, you have this unhealth obsession with so-called "point charge". If you have studied physics at any considerable level, you would have noticed that the classical electrostatic description has an equivalent form to the classical gravitational description. There is a gauss's law equivalent for gravitational field, for example. Every single description for an electrostatic field, there is an identical equivalent for a gravitational field (except for the absence of an repulsive force). Thus, gravitational force ALSO considers the mass being acted upon as point mass sources! Someone should have clearly pointed this out in your original "derivation" of gravitational force. Don't believe me, go double check what you did... you put ALL of the mass of the proton to be at the radius of another proton. Ignoring the obvious fact that you have two protons overlapping each other already, you yourself are doing the very thing you are criticizing, lumping the mass of an object into a point mass.

So get over this "point charge" problem already.

 I have explained why gravity would not turn off inside the nucleus. What evidence do we have that EM forces actually exist between protons in a He nucleus?
What evidence that it doesn't? We have no description or evidence that EM forces can just simply disappear. It is YOUR responsibility to prove that your "new imagination" has a valid impetus to be considered other than just something you thought of out of ignorance.

 Of course H atoms bind with EM molecular binding forces. I said "EM binding energy well" to distinguish it from nuclear binding energy. My point was that there appears to be a fundamental difference between the two. Molecules can be separated without adding mass to the nuclei or electrons that compose those molecules. Nuculeons cannot be separated without adding mass to the nucleons. I was not trying to change the subject. I was just pointing out that separation of atoms in a molecule (which derives from a $1/r^2$ force and therefore a $-1/r$ energy potential) is very different from the separation of nuclear particles. I point out that one difference is that overcoming the nuclear potential results in adding mass to the separated parts (nucleons) while overcoming the EM potential does not add mass to the separated parts. While the energy required to separate atoms is the due to the need to apply a force over a distance, the energy required to separate nuclei is needed to create mass. Perhaps instead of looking at the nuclear binding energy as a continuous force between nucleons, we could look at it as a 'barrier' to separation. The analogy would be to a can of beans. The can prevents them from escaping. But it does not create a continuous force between the beans. I am merely suggesting that if we looked at the nuclear potential in these terms, we would not need to invent a force that is enormous within a tiny distance (1 f.) and is effectively 0 outside that distance, and becomes repulsive at very short distances so as not to squish the nucleons. Andrew Mason
This last set of paragraphs are a complete mystery to me. What EXACTLY is this about? Adding mass and not adding mass?? Applying force over a distance? Huh??!! I have to add mass to separate nucleons? Tell me where I am adding mass in an alpha decay? And if you are somehow thinking that separated daughter nucleons ALWAYS have a higher total mass than the original parent nucleus, I have a fission reactor I want you to meet.

You are not suggesting anything. You are trying to ignore a huge part of physics that you have no clue on (QCD), and trying to replace it with your faulty physics knowledge. In the process, you are doing the exact same thing you are finding faults in with EM and QED. But what is even more appaling is that you are STILL insisting there is some validity in your faulty idea inspite of (i) your admission of lack of any serious knowledge in the matter you are talking about and (ii) the REPEATED explanation of those who are more knowledgable than you on why your idea is wrong.

In the end, I find it ironic that you would spend time quoting Gell-Mann for something that suits your needs, and yet you blatantly reject his most significant contribution - the quarks and how they interact. I hate to think that this is how you practice your profession.

Zz.