mind blown like hot glass

During a recent morning conversation Bjorn gesticulated a graph of the matter in the universe, showing me where most of the matter is {hand wave} and that it's hydrogen {hand particle}, then helium, then &c. &c., and the rest is here {wild graph gesticulation} in the tail {wag}.
   'What about dark matter?' I said. 'Is it in the tail?' Not in the tail. From there, somehow, by some parallel move, or some tangential veer, or some unobserved cat, the conversation came to this ... Maybe, he said, maybe dark matter has its own periodic table.

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