Title:
«On the wave-like nature of fuzzy dark matter. Modeling, phenomenology, and limits from the bottom up»
Main Research Findings:
Since the advent of observational evidence for the mysterious, gravitationally interacting substance dubbed dark matter (DM) about a century ago, physicists have worked relentlessly to uncover its microphysical nature. Impressive theoretical frameworks have been developed, and increasingly sophisticated detectors constructed—yet, no direct detection has been achieved. Astrophysics offers a complementary perspective: rather than asking what dark matter is, we ask how it behaves.
In this thesis, I focus on ultralight (or “fuzzy”) dark matter—a class of models that posits the DM particle to be roughly a hundred billion billion billion times lighter than a proton. So light, in fact, that its dynamics resemble those of a wave rather than a classical particle, giving rise to a distinct set of phenomena in a “fuzzy” universe.
To this end, I decompose FDM’s dynamics and phenomena into their elementary building blocks. Lower-dimensional considerations allow me to compare and further develop numerical solution strategies. By reconstructing all possible FDM wave states within the dwarf galaxy Leo II, I derive a robust mass constraint that updates four-decade-old folk wisdom. Finally, by assembling a population of simplified yet fuzzy cosmic filaments, one at a time, I statistically reproduce results of fully-fledged simulations at significantly lower cost.
Image: Wave function density of ultralight DM for the dwarf spheroidal galaxy Leo II. The granular interference substructure is a hallmark feature of ultralight DM.
Credits: Tim T. Zimmermann
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Trial Lecture: «Could pulsars be the progenitors of fast radio bursts?»
Time and Place: June 19, 2025 10:15 AM CEST, Auditorium 209 Svein Rosselands hus.
More information can be found on this webpage:
https://www.mn.uio.no/astro/english/research/news-and-events/events/disputations/2025/Tim_Tobias_Zimmermann
Also check out other Workshops in Oslo.
