NPA Seminar: Nickolas Kokron, Princeton, "Probing the S(igma)-8 tension at the onset of stage-IV cosmic surveys"
In 1970, Allan Sandage famously described Cosmology as “A search for two numbers”. In the half-century since that description of the field was penned, as Stage III cosmic surveys come to an end and Stage-IV surveys begin taking data, the field finds itself having measured the six parameters of the concordance ΛCDM model at nearly 1% precision. However, different experiments now report different values for two of these parameters – namely the Hubble Constant and the variance of dark matter density fluctuations, S(igma) 8 – at varying levels of significance.