"[1] Kaiser's physics research mostly focuses on early-universe cosmology, including topics such as cosmic inflation,[9] post-inflation reheating,[10][11][12] and primordial black holes.

[17] Kaiser and his colleagues have studied mechanisms by which a population of primordial black holes could have formed during the very early universe in models that preserve the close fit between predictions and observations of the cosmic microwave background radiation.

Additionally, they have proposed a new observable test to help establish whether primordial black holes exist and contribute significantly to dark matter abundance, based on high-precision measurements of visible objects within the Solar System, such as the planet Mars.

[26] Kaiser's historical research focuses on intersections among modern natural sciences, geopolitics, and the history of higher education during the Cold War.

In addition to his scholarly writing, Kaiser's work has appeared in The New York Times,[27][28][29][30] the New Yorker magazine,[31][32][33] and in several PBS Nova television programs.

As an invited advisor to a U.S. National Academy of Sciences panel during 2023-24, Kaiser helped to draft a consensus statement regarding generative artificial intelligence and scientific integrity,[35] as well as providing historical context for societal reactions to previous once-new technologies.