Light Species in Cosmology and Particle Physics

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


There are many reasons to believe that the Standard Model of particle physics is incomplete. Models of physics beyond the Standard Model usually invoke new degrees of freedom, many of which contain new light species that are efficiently produced in the early universe. In this chapter, we provide the connection between cosmological observables and these additional light relics predicted beyond the Standard Model. Apart from order-of-magnitude estimates for the constraining power of astrophysical systems and cosmology, we introduce the particle physics aspects of this thesis, discuss the main cosmological parameter capturing neutrinos and any other light thermal relics, and examine the possible signatures of these particles in cosmological observables.


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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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