• Benjamin WallischEmail author
Part of the Springer Theses book series (Springer Theses)


Cosmology is a sensitive probe of particle physics, both within the Standard Model and beyond it. In fact, cosmological observations have now become precise enough to start complementing laboratory and collider experiments. For example, by measuring the radiation density of the universe, future observations may provide further insights into the properties of neutrinos. Moreover, if these measurements reach sub-percent level, they have the potential to discover particles that are more weakly coupled than neutrinos, which are predicted in many interesting models of physics beyond the Standard Model. In this chapter, we give a concise introduction to the topic of this thesis, the search for these elusive particles by identifying and extracting their robust signatures in cosmological observables. Moreover, we outline the rest of the thesis and provide a collection of the employed notation and conventions.


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© Springer Nature Switzerland AG 2019

Authors and Affiliations

  1. 1.School of Natural SciencesInstitute for Advanced StudyPrincetonUSA
  2. 2.Department of PhysicsUniversity of CaliforniaSan Diego La JollaUSA

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