Upcoming Colloquia

Affiliation: UVU
Time: 4:00 PM
Location: C215 ESC or Live Online

Addressing the Hubble Tension with JWST

The sharp conflict between the current expansion rate of the universe (the Hubble constant, or H0) measured using the local extragalactic distance ladder and the value of H0 derived from the cosmic microwave background has the potential to reveal the presence of additional physics beyond the LCDM standard model of cosmology, so reducing and eliminating sources of systematic uncertainty in the local distance scale is of paramount importance. I will describe our efforts to calibrate the surface brightness fluctuation technique using the tip of the red giant branch to enable measurements of H0 at distances beyond 200 Mpc with JWST while minimizing systematic uncertainties. The results of our TRGB+SBF project are completely independent of the Cepheid+supernova distance ladder and form one of the key components of a new “Distance Network” that has now been used to accurately assess the covariances between various distance measurements and techniques. The Distance Network results reaffirm the reality of the Hubble tension at the 6-sigma level and further reduce the systematic uncertainties on H0, providing evidence that additional physics beyond cold dark matter and traditional dark energy may exist. 

Biographical Sketch:

Dr. Joseph Jensen is an astronomy professor in the Physics Department at Utah Valley University. He currently uses the Hubble and James Webb Space Telescopes to study the size and expansion rate of the universe by measuring distances to galaxies hundreds of millions of light years away. He received his Ph.D. in astronomy from the University of Hawaii at Manoa. Dr. Jensen worked at the Gemini Observatory for 12 years during the construction and commissioning of the twin telescopes. Dr. Jensen has been at UVU for 16 years and works with undergraduate students on optical and infrared imaging projects in cosmology.

Affiliation: University of Maryland
Time: 4:00 PM
Location: C215 ESC or Live Online

Cosmology and Unification

 I will describe the mechanism of “cosmological collider physics” in which precision cosmological measurements can allow us to probe particle physics and cosmic inflation at energies which are orders of magnitude above those of terrestrial particles colliders such as the CERN Large Hadron Collider. I will show how this may give us unprecedented access to some of the highest ambitions of fundamental physics such as the Grand Unification of the forces of Nature.

Biographical Sketch:

Raman Sundrum is the John S. Toll Chair and Distinguished University Professor of Physics at the University of Maryland and Director of the Maryland Center for Fundamental Physics. He earned his BSc at the University of Sydney and his PhD at Yale. He did postdoctoral research at Berkeley, Harvard, Boston University, and Stanford.

Raman works on the structure of the fundamental forces, their possible roles in the very early Universe, and their connections to possible extensions of Relativistic Spacetime, such as Supersymmetry and Extra Dimensions. His research provides theoretical templates for a broad range of experiments, from CERN's Large Hadron Collider to precision cosmological measurements. 

In 2019, Raman was awarded the J.J. Sakurai Prize for Theoretical Particle Physics of the American Physical Society along with his former collaborator, Lisa Randall of Harvard University, for their pioneering of what are now known as the “Randall-Sundrum” models of warped higher-dimensional spacetime.

Affiliation: Siemens Corp
Time: 4:00 PM
Location: C215 ESC or Live Online

Affiliation:
Time: 4:00 PM
Location: C215 ESC

Affiliation:
Time: 4:00 PM
Location: C215 ESC

Affiliation: BYU Physics and Astronomy
Time: 4:00 PM
Location: C215 ESC