**************************************EXCERPT***************************************
Introduction
One of the central arguments in favor of the Big Bang theory is that it explains well the chemical abundance within the Cosmos. It describes, for example, why hydrogen and helium should vastly dominate the other elements as a percentage of visible matter and, in fact, this is precisely what is observed by astronomers. Thus, hydrogen and helium make up perhaps ninety-nine percent of the ordinary visible matter in the Universe. The elements heavier than hydrogen and helium up to iron are fused supposedly in the stars as they evolve by consuming their atomic components in fusion processes. Elements heavier than iron are catastrophically fused via supernovae explosions, the terminal phase of a stars fusion cycle. This is the orthodox convention.
For those scientists who disagree fundamentally with the Big Bang occurrence, their alternative theories have had difficulty explaining the dominance of hydrogen in the Universe. Thus a key question arises: If there was no Big Bang in the distant past, how can there be so much hydrogen as observed in the Cosmos? It is the approach of this paper that neutrino oscillations may provide such a plausible alternative mechanism whereby hydrogen can be fabricated without invoking a Big Bang-type creation event.
The other possibility is that if there was a Big Bang event, vastly less hydrogen was fabricated by it. Perhaps, neutrinos which were likely to be high energy in the early Universe, "off-loaded" their energy into the early planetary-type objects fabricating hydrogen atoms. Hence, hydrogen is created in the cores of the planets causing the evolution of such objects to larger bodies. This is an ongoing process today.
Moreover, the fusion of slow neutrons which then beta decay to fabricate higher elements may take place at or near the core of a planet. Thus, the fusion of hydrogen is taking place within planets as well as stars. The common beta-decay process, provides a standard mechanism which enables nuclide to nucleus fusion at low energies and provides a fabrication pathway to heavier elements over time. Another consideration is that hydrogen is joining-up with other elements to form simple molecules such as ordinary water and hydrated minerals in the liquid outer core. This offers a different explanation of the origin of the oceans on Earth.
***********************************EXCERPT********************************
We now know that there are (at least) three flavours (types) of neutrinos: the electron-neutrino, the muon-neutrino and the tau-neutrino (this last one has not been observed yet, but its existence is inferred by analogy) and their anti-particles. We do not know if neutrinos have mass since all attempts to measure their mass have failed (see neutrino experiments).
However, if neutrinos actually have mass, it does not necessarily mean that the electron neutrino has a fixed mass, the muon-neutrino has another fixed mass and the tau-neutrino yet another. It is possible that an electron-neutrino, for example, is a composite particle made up of different massive neutrino states. This might sound like a weird idea, but actually this is exactly how the different types of quarks (the constituents of all hadrons such as nucleons and other baryons or mesons) operate amongst themselves. In fact, the quarks that suffer decays are a mixed state of the quarks that have a definite mass. This property is called mixing, so it is thought that if neutrinos have mass, they too could be in a "mixed mass state".
For simplicity, we could assume that for example the electron-neutrino is made up of two mass states (which we could call 1 and 2), so if an electron-neutrino is created in some interaction (for example, in the sun) then as it travels, each of the mass states travels with a different speed. This means that the electron-neutrino travelling through space is no longer a "pure" electron-neutrino but might be partly electron-neutrino and partly muon-neutrino. As the neutrino continues to travel, the proportion of each vary with distance, so it is said that neutrinos oscillate from one state to another. If we set-up a detector along its path, it would then be possible to observe not only the interactions of the electron-neutrino but the interactions of the other component (muon-neutrino in this example). If we saw muon-neutrinos where we would only expect electron-neutrinos we would observe the phenomenon of neutrino oscillations (appearance experiment), but it could also manifest itself if we saw that some of the original neutrinos were not there any more (disappearance experiment). As one can see, it is absolutely necessary that for this property to be visible that neutrinos must have more than one mass state (that is, neutrinos must be massive and the masses of each of the mass states must be different ). The proportion in which the two mass states can mix inside each neutrino flavour is called the mixing angle and is not known. If neutrino oscillations could be observed, this would be one of the parameters (with the mass difference) that could be determined.
There are a large number of experiments trying to observe neutrino oscillations. Some rely on man-made sources like nuclear reactors or accelerators and others rely on "natural" sources such as solar neutrinos or neutrinos from cosmic-rays (otherwise known as atmospheric neutrinos). All of these nutrino oscillation experiments are complementary because they involve neutrinos of different energies travelling over differnt distances. Since we do not know what the mixing angle and the mass difference is between the neutrino species we need to try and cover as much of our "parameter" space as possible to be able to discover oscillations in the future.