Jump To Date
View By Semester
View By Series
Add An Event

Center for Astrophysics Research and Technologies Seminar Series Information


Events Calendar

A Challenge to the Standard Cosmological Model

Friday February 2, 2024
3:30 pm

 Presenter:  Prof. Subir Sarkar (University of Oxford)
 Series:  Physics and Astronomy Colloquium
 Abstract:  In the ΛCDM cosmological model the Universe is assumed to be isotropic and homogeneous, when averaged on large scales. That the cosmic microwave background (CMB) has a dipole anisotropy is interpreted as due to our peculiar (non-Hubble) motion because of local inhomogeneity. There must then be a corresponding dipole in the sky distribution of sources at high redshift. Using catalogues of radio sources and quasars we find that this expectation is rejected at >5σ, i.e. the distribution of distant matter is not isotropic in the 'CMB frame’. This calls into question the standard practice of boosting to this frame for analysing cosmological data, in particular to infer an (isotropic) acceleration of the Hubble expansion rate from Type Ia supernovae, which is interpreted as due to a Cosmological Constant Λ.
 Web Site:    https:/ / goto.unm.edu/ rth4a
 Host:  Rouzbeh Allahverdi
 Location:  Zoom

Disability Notice If you need an auxiliary aid or service to attend any Department of Physics and Astronomy event, please contact the department (phone: 505 277-2616; email: physics@unm.edu) as far in advance as possible to ensure you are accommodated.