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First at all - if I understood right - the existence of antiquarks is hypothetical. Your understanding is entirely incorrect. Anti-quarks are a work-a-day reality in the particle physics world. The annihilation of quarks and anti-quarks to form lepton pairs (i.e. Drell-Yan scattering) is not merely regularly observed, it is used a physics tool to ...


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First at all - if I understood right - the existence of antiquarks is hypothetical. If one not agree with this please refer to experimental data which shows their observation. Everything we observe can be considered hypothetical for each of us. It is a hypothesis that you have a screen and are reading this. Maybe it is all a hypotheis in my mind , or ...


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You didn't understand any of these questions right. Antiquarks and their bound states, including the antineutrons, are produced and observed as easily as bread and butter. Lots of details experiments with e.g. antineutrons have been performed, e.g. Scattering of antineutrons with hydrogen ...


1

The liquid drop model (LDP) is an approximate description of the mass of nuclei. It is a parametric formula that is fitted to the experimental values. The formula for binding energy is expressed in a similar way and comes from the same assumption. Therefore, both being parametrizations, they are approximate. And indeed if you examine nuclei by nuclei it will ...


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I think I've get a better idea of what you are looking for now, thanks. As background for others in the future: classic ion-solid interaction theory dates back to the 1960s and is commonly called LSS theory after Linhard, Scharff, and Schiott who first formulated the concepts. It splits the energy loss mechanisms of the ion into two components, electronic ...


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The electrons released in $^{60}$Co decay are mostly only about a third of a MeV in energy and are easily stopped. For example if your source is inside a metal foil the electrons will be blocked by it and only the gamma rays will get out. The source you're using may have been deliberately designed to block the electrons.


3

To a first approximation we can describe the nucleus with a wavefunction that ignores the electrons and also ignores the fact the nucleons are made up from quarks. Actually solving the Schrodinger equation for a many body strongly interacting system like a nucleus is impossible, but we expect there will be a ground state and excited states just as there are ...


1

Please keep in mind that physics does not answer "why" questions on the very basic observations that generated the need for a theory/mathematical model. Your question touches on one of the basic reasons that quantum mechanics was developed as a theory of the microcosm, and thus its only answer is really "because that is what we have observed". I read a ...


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Of course the electron can "fall" into nucleus. In neutron stars this happens. The question is why the atoms stable in our surroundings. The classical physics can't give an answer because the permanent electrons acceleration during his circular move around the nucleus would have to be accompanied by radiation and the loss of speed. But this does not ...


2

I read a book on pop sci book on quantum mechanics and the author said that electrons do not fall into the nucleus due to quantum mechanics- which principles suggest this (I think it was Heisenberg's Uncertainty and Pauli's Exclusion Principle) and why? The basic argument can be based on two things from non-relativistic Schroedinger theory: 1) for ...


3

50Mt TNT means that the energy is equivalent to 50 000 000t of TNT, and 1t of TNT is equivalent to 4184 MJ. So Tsar Bomba released 50 000 000 * 4184 = 209200000000 MJ = 2*10^11 MJ. Now, given that E=mc², we have m=2*10^17/299792458²=2.3kg as said above. For comparison, Little Boy did not convert more than 1g... PS : I'm sorry I cannot comment the ...


1

The most powerful hydrogen bomb ever exploded had a TNT equivalent of 50 Mt TNT, if I remember correctly, TNT energy equivalent is 4184 MJ/kg, that gives a mass loss of about 2.3 kg, if my calculations are correct.


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What mechanism decides when an unstable nucleus decays? [...] Let me rephrase that question so: "Given some initial number of (otherwise equal) objects, and having measured the sequence of their subsequent decays (if any), what can we conclude about the mechanism, or "barrier", which had prevented them from each having decayed/disintegrated right ...


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Your question addresses a general principle in quantum mechanics. If we have an initial state $i$ and a final state $f$ then we can calculate the probability of a transition from $i$ to $f$, but this is only a probability - we cannot say when the transition will happen, only the probability that it will happen in some time interval. This isn't because we ...


3

As far as we know, nuclear decay is truly random, that is, random in the quantum mechanical sense. That is, when you observe the system, there is a probability that you will see the decay products rather than the original nucleus, because the wave function of the system is a superposition of the parent nucleus state and the daughter nucleus state (+alpha ...


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I am not a nuclear physicist but I have studied these structures. Bolonkin is not a fool. He knows what he is talking about. The claim that "everything possible occurs in nature" is not true. While fullerenes and tetrahedral carbon/diamond does occur, and while you could point to "natural" stainless steels, such as iron-cobalt-nickel meteorites, I can point ...


2

Sounds like kook material. If his hypothetical material consists only of N neutrons and Z protons, then it has a nonzero net electric charge and can't possibly be a stable form of matter. The electrical potential energy would go like $Z^2$, while the nuclear potential energy would vary linearly with $N+Z$, because the nuclear force has a short range.


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Everything that's physically possible occurs naturally. Atoms arrange themselves naturally into one- and two-dimensional structures (lipid and polymer chains in 1D, graphene and nanotubes from soot in 2D) and so we're able to envision techniques to mass-produce those. But there's no evidence that nucleons form chains in nature (at least outside of neutron ...


1

Are my assumptions for the approximations correct ? I think no. If you make the neutrino mass-less, such reaction cannot occur for your conditions, because the invariant made from left side is zero and from right side non-zero (Z boson mass squared). You have to keep the neutrino mass in the game. By the way you use the 4-vectors in a wrong way, e.g. ...


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The direction of propagation of a shock wave does matter. However, a shock wave can diffract and refract, i.e., it propagates not just along the line-of-sight and can penetrate through concrete walls, so it can enter a building through windows in a wall of a building that does not face the explosion, and it can penetrate concrete walls of the building, ...


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There are quite a few different versions of the Born potential. Most popular ones include the Bonn-A, B, C (with different strength for tensor force) and the Charge dependent Bonn (CD-Bonn) potential. CD-Bonn 2000 is the most recent one. None of the three potentials you mentioned are chiral potential. They are based on meson exchange potential.


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Assuming that by escape velocity you mean exhaust velocity, then the velocity comes from the Maxwell-Boltzmann distribution. This gives the velocity distribution of the particles in a gas as a function of temperature. For our purposes we can use the most probably speed, i.e. the peak in the distribution, as a rough estimate and this is given by: $$ V_e = ...


0

Can we use heating to separate electrons from their nucleus? With the following 'conversion factor' between temperature and energy: $$ {1 \over k_{\text{B}}} \approx 11600 \, \text{K/eV} $$ you'll see that 1'000'000 Kelvin corresponds an average energy of about 86 eV, much more than enough to fully ionize (separate the electron from the nucleus) e.g. ...


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To produce electrons one simply heats up a piece of metal, and they come boiling off. If you want a beam of electrons, you just set up a positively charged plate nearby, to attract them over, and poke a small hole in it; the electrons that make it through the hole constitute the beam. Such an electron gun is the starting element in a television tube or an ...


3

By a high temperature we just mean that the particles in our gas are moving rapidly. The velocity of the particles is related to the temperature by the Maxwell-Boltzmann distribution (though note this only applies to temperatures where the velocities are non-relativistic). Anyhow, once the velocities of the atoms are high enough that the collision energy is ...



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