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7

Life is not so simple, as in all high energy interactions there is a probability of a large number of particles appearing at the main interaction which will subsequently have decays through the weak or electromagnetic interaction. If one sees jets of hadrons in the detectors the strong interaction is involved, but the main vertex may be electromagnetic, ...


5

I will try to illustrate the sizes for you in my answer. However, with the examples you gave from the article and TV show, that is nonsense...they may be right with the size comparisons, but that is not an illustrative point. You kind of have to take that type of pop-science with a (large) grain of salt. First, let's familiarize ourselves with units. We'll ...


3

All objects and fields that have a nonzero mass, energy, or momentum interact gravitationally, and so do neutrinos – although they're very light and hard to produce so the gravitational force from any neutrinos we know is undetectable at this time. Neutrinos also have negligible but nonzero interactions with the electromagnetic field. They're uncharged and ...


3

In a nutshell, no. Part of the problem seems to be that you misunderstand the fundamentals of string theory. The strings do vibrate. The frequency of these vibrations determines the type of particle and the energy of the string determines the energy of the particle. Second, your understanding of the uncertainty principle isn't quite right. Yes, we cannot ...


2

An explicit mass term violates Gauge invariance, because left and right particles belong to different representations 2.At one loop, the lepton mass is given by $m_{1L} = M_{bare} + \Delta M_{1L}(\mu = m_{1L})$ this condition uniquely defines the bare mass. The correction $\Delta M(\mu)$ is anyway proportional to some power of the yukawa, thus is very ...


2

Because no rational process can make them. I've been over the tables, and there are only a couple of possible reactions to get there for any nuclei, and they require two rare ones. Alpha particle capture just isn't going to cut it. Look at the curve; you need more neutrons. We remember that all elements heavier than iron have primary sources as neutron star ...


2

The mass of the neutrinos are estimated to some tenths of an $\mathrm{eV}$. The masses of atoms are mostly between 1 and 300 $\mathrm{GeV}$. Thus, considering the masses, this golf ball comparison isn't okay in my opinion. In my mind, comparing the mass of the Moon to the mass of the Solar System would be more realistic. Their sizes can't be easily compared,...


1

A neutrino is thought to interact only through the weak force and gravity. They interact primarily, though, through the weak force (perhaps explaining the Martin/Shaw comment). Interestingly, since the neutrino has a minuscule mass (as opposed to none at all), it could have tiny neutrino magnetic movements, therefore allowing the possibility that it could ...


1

I had the same doubt as I was figuring out if a certain coupling of angular momenta in the 3$\gamma$ could be found such that parity would be conserved. Turns out (if I am correct) you cannot have three photons with coupled total angular momentum $J=0$ in the first place. For the coupled photon angular momentum $L(3\gamma)$ and spin $S(3\gamma)$ to be able ...


1

As far as I am concerned, I think you shouldn't take the question particle/anti-particle too literally. Here is why: Take you first picture. The bubble on the right hand side does represents a process which does not have a well defined stop or starting point. You could interpret it as (an this is how it is typically done) a particle anti-particle pair being ...


1

First of all, physical descriptions usually cannot be proven in a mathematically sense. Of course they should make sense and therefore mathematically sound. In particular when it comes to particle and antiparticles which is a concept of relativistic quantum field theory (QFT), actually a wavefunction as it exists in quantum mechanics no longer makes sense. ...


1

Producing ultra-heavy elements in nature is not easy. So their absence "in nature" does not mean they cannot exist or cannot be created given the right conditions. Some details: The valley of stability becomes increasingly n-rich, so neutron capture reactions are essential. To get beyond lead requires rapid neutron capture in the r-process. The ...



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