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Among the many Dark Matter candidates, I wondered if there are any along the lines of the title.

The inner horizon of a black hole, with its mass inflation, and/or the high spacetime curvature, seems a violent enough place for the strangest things to happen that can anywhere, and tachyons (if these exist) seem to have enough counterintuitive properties that they might perceive far greater space volumes accessible inside black holes than outside, so that any created inside and straying out would readily tend to find their way back into the same or another black hole, with some energy change while in transit that would manifest itself outside the hole(s) as "dark mass" (assuming this was a fairly steady state process).

Piling speculation on speculation, one might further envisage that a tachyon which exited a black hole and lost enough energy outside (and hence gained speed) for long enough might greatly increase its chance of staying outside and thus manifest itself as dark energy.

The latter would also explain why the expansion of the universe is accelerating: If the average distance between black holes (between galaxies for example) is increasing with cosmic expansion, then on the preceding assumption slightly more tachyons can be expected to remain outside black holes, and so on.

It seems all this would make most sense (if at all) if tachyons appeared somehow "spread out" in normal space, like a field, as opposed to conventional sub-luminal particles.

Apologies if this is all too vague and speculative for some peoples' liking. I am not axe-grinding, quite the opposite, just curious to hear any informed comments on an idle fancy which is most likely untenable.

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It is a very, very, very, speculative question. However, simple to settle, dark matter must exist before any black hole is formed. One usually need cold dark matter in the interval around the recombination so the perturbations can grow enough to form the structures that we see now. Note also that it needs to be cold to not spoil the growth of structures, therefore, your tachyons in some way must also act like a gas of cold particles.

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Thanks for the prompt reply - I'll wait for a day or two to see if any more appear before marking it the accepted one. Meanwhile, to address your point, if high spacetime curvature is behind the mechanism I sketched, couldn't slight fluctuations late in Big Bang inflation act like miniature black holes and produce a surge of dark matter, in the manner I indicated, sufficient to halt inflation, leaving a small residual expansion, before conveniently evaporating? Seems to me this could account quite naturally for the balancing act whereby inflation became a Cosmological Constant of almost zero. –  John R Ramsden Sep 19 '12 at 16:46
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@JohnRRamsden Actually, in the final phase of inflation the spatial curvature is almost zero (for most of the inflationary models), also the perturbations are of order $~10^{-5}$, not enough to generate any kind of structure. On top of that, in general, is believed that all matter is created (or heated) after the end of inflation, so we don't usually want dark matter in the end of inflation. –  Sandro Vitenti Sep 19 '12 at 17:07
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@JohnRRamsden As a general note, all these mechanisms like inflation, dark matter and dark energy are very much constrained by the inner works of the standard cosmological model and some parts of it by observations. It is necessary to understand very well all these mechanisms before trying to propose a new one. Only after you know all the constraints and all things that dark matter has to explain you will be able to suggest something without bumping into these constraints. –  Sandro Vitenti Sep 19 '12 at 17:14

protected by Qmechanic Feb 23 '13 at 20:13

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