-----Original Message----- From: mix...@bigpond.com Is it possible that there is an unknown CF mechanism at work in the universe creating extra D? ;)
Such a mechanism would have to be "unknown" since according to Wiki there is no known ongoing mechanism to create deuterium, and the amount we see all comes from initial condition. What did you have in mind for this mechanism? In the "unknown category" there is speculation, and one mechanism for creation involves dark matter. I have a minority perspective on this too, which I will include at the end, but it is not exactly an ongoing mechanism. To paraphrase Wiki: Deuterium is unlike helium-4 which is very stable and constantly increasing, whereas deuterium is marginally stable and easy to destroy, so there should be net decrease over time.... One consequence of this is that unlike helium-4, the amount of deuterium is very sensitive to initial conditions. The denser the universe is, the more deuterium gets converted to helium-4 before time runs out, and the less deuterium remains. There are no known "post-Big Bang" processes which would produce significant amounts of deuterium. Hence observations about deuterium abundance suggest that the universe is not infinitely old, which is in accordance with the Big Bang theory. ... The problem is the concentration of deuterium is too high to be consistent with a model that presumes that most of the universe consists of protons and neutrons. If one assumes that all of the universe consists of protons and neutrons, the density of the universe is such that much of the currently observed deuterium would have already been burned into helium-4. After a decade of effort, the consensus is that processes to produce deuterium are unlikely, and the explanation now used for the abundance of deuterium is that the universe does not consist mostly of baryons, and that non-baryonic matter (also known as dark matter) makes up most of the matter mass of the universe. By implication some could be converted into deuterium. END of paraphrase. This being show-and-tell day, my minority perspective on this subject, which is borrowed from a number of sources, is that there was NO single big bang at all. Instead (while having a similar effect) there have been an ongoing succession of little bangs, in an infinite universe. The little bang is the lifetime feature of any "supercluster complex", defined as all the galaxies and stars which are blue-shifted relative to the observer. There can be hundreds of "local groups" (clusters of 50-100 galaxies) in each "supercluster complex" (SCC) all blue-shifted, but each and every one of these SCC are red-shifted relative to every other one. In effect, each SCC is in its own fractal (fractional dimension) and is spatially independent of the other SCC. An adjoining (very old) SCC can collapse and re-expand without affecting neighbors since every fractal is dimensionally isolated. Each of these SCC has a shorter lifetime than the present age of the universe. This can explain why there can be lots of deuterium (comparatively) in some of the cooler local groups, like our Milky Way. A hotter or denser galaxy, even in our SCC, could have almost no deuterium since it was converted to helium early on.
