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Overwhelming evidence now suggests that the majority of the matter in our universe consists of some exotic "dark matter" that neither emits nor absorbs light, yet makes its presence felt via its gravitational pull on normal matter. Nevertheless, despite an impressive array of experimental efforts to uncover additional information about this dark matter --- for example, whether it "feels" any forces other than gravity --- the nature and origin of this exotic form of matter remain a mystery. In this talk, after reviewing the present state of our knowledge about the dark matter, I'll present a novel strategy through which we might be able to learn about its fundamental properties --- a strategy which, notably, does not rely on the assumption that dark matter interacts with normal matter through any force other than gravity. In particular, I'll show how detailed information about the way in which dark-matter particles were produced in the early universe can be imprinted on the distribution of speeds that those particles acquire. I'll then show how information about that distribution of speeds, in turn, is imprinted on the spatial distribution of matter that we observe today. Finally, I'll introduce a remarkably simple, empirical procedure which actually permits one to work backwards and reconstruct information about the dark matter from this "archaeological record" of its production. This reconstruction procedure provides a potentially useful tool for probing the properties of the dark matter --- especially in situations in which standard experimental probes of dark matter have little or no sensitivity.

Overwhelming evidence now suggests that the majority of the matter in our universe consists of some exotic "dark matter" that neither emits nor absorbs light, yet makes its presence felt via its gravitational pull on normal matter. Nevertheless, despite an impressive array of experimental efforts to uncover additional information about this dark matter --- for example, whether it "feels" any forces other than gravity --- the nature and origin of this exotic form of matter remain a mystery. In this talk, after reviewing the present state of our knowledge about the dark matter, I'll present a novel strategy through which we might be able to learn about its fundamental properties --- a strategy which, notably, does not rely on the assumption that dark matter interacts with normal matter through any force other than gravity. In particular, I'll show how detailed information about the way in which dark-matter particles were produced in the early universe can be imprinted on the distribution of speeds that those particles acquire. I'll then show how information about that distribution of speeds, in turn, is imprinted on the spatial distribution of matter that we observe today. Finally, I'll introduce a remarkably simple, empirical procedure which actually permits one to work backwards and reconstruct information about the dark matter from this "archaeological record" of its production. This reconstruction procedure provides a potentially useful tool for probing the properties of the dark matter --- especially in situations in which standard experimental probes of dark matter have little or no sensitivity.