Astronomy Colloquium for 2024-09-25


Series: Astronomy Colloquium
Date: Wednesday 25-Sep-2024
Time: 16:05-17:00 (4:05-5:00 pm)
Location: ATL 2400
Speaker: Dr. Dan Scolnic (Duke University)
Title: Measurements of the Expansion Rate of the Universe and the Lingering Hubble Tension

The standard model of cosmology has passed every test over the last twenty years. Yet it remains unsatisfactory, with 95% of the universe being dark components, whose nature we did not understand. Now, there are possible 'cracks' in the model, as recent observations of the local expansion rate of the universe, parameterized by the Hubble constant, do not match predictions using data from the Cosmic Microwave Background and our standard model. This is the best end-to-end test of our cosmological model, and currently, we do not pass the test. I will discuss my team's Pantheon+SH0ES measurements on the local side, and review the numerous crosschecks and tests on our data and analysis. I will show new data from the James Webb Space Telescope and explain how it strengthens the current tension. Finally, I will talk about how the community is moving forward, with different probes of the early and late universe, and what new theoretical ideas show the most promise.


In-person colloquia are usually preceded by espresso and ice cream at 1:45 pm outside room PSC 1150 and are followed by an informal reception at 5:15 pm in that room. Anyone interested in talking with the speaker, or being added to the colloquium announcement email list, should contact the colloquium organizer Dr. Richard Mushotzky. Lunch will normally be reserved for the speaker to talk to graduate students. Anyone asking a question during a talk is asked to raise their hand and be acknowledged before speaking. Contact Dr. Richard Mushotzky for details.

Colloquium Organizer: Dr. Richard Mushotzky

SPECIAL ACCOMMODATIONS:

Special accommodations for individuals with disabilities can be made by calling (301) 405-3001. It would be appreciated if we are notified at least one week in advance.

DIRECTIONS, PARKING, AND OTHER INFORMATION FOR VISITORS

Directions and information about parking can be found here.

This page was automatically generated on: 07-Oct-2024.