Colloquium
Upcoming Colloquium
The "Hubble Tension": Measuring the Expansion History of the Universe with Gravitational Time Delays
Dr. Tommaso Treu, UCLA
September 23, 2024
11:00am in HSCI-102
The standard LCDM model gives a successful description of many astrophysical observations. However, in the past few years a tension has developed between local determinations of the current expansion rate of the Universe (the Hubble constant) and the value predicted from early universe probes. If confirmed, this so-called Hubble Tension would require additional physical ingredients beyond LCDM, e.g., early dark energy, or new particles. After describing the tension, I will provide an update of a 25-year long effort to measure the expansion history of the universe and thus the Hubble constant using gravitational time delays, highlighting recent results based on lensed quasars from the TDCOSMO collaboration (the union of H0licow/STRIDES/SHARP collaborations), and from multiply imaged supernovae, including Refsdal. I will show new JWST HST Keck and VLT data that we are currently analyzing with the goal of achieving 1-2% precision and accuracy on H0 and thus contribute to the resolution of the Hubble tension.
About the Colloquium
The Colloquium is a unique opportunity for students to learn about new developments in physics and what physicists do after they graduate. Hosted by the Physics and Astronomy Department at California State University, Long Beach, the weekly meetings invite guests from universities, research laboratories, and industry to present and discuss current topics in physics. All students are encouraged to attend for a well-rounded experience and training in physics.
Colloquium Coordinator
For information and suggestions about the colloquium please contact the colloquium coordinator:
Dr. Michael Peterson
Michael.Peterson@csulb.edu
Schedule
| Date | Title | Speaker and Affiliation |
|---|---|---|
| September 23, 2024 | The "Hubble Tension": Measuring the Expansion History of the Universe with Gravitational Time Delays | Dr. Tommaso Treu, UCLA |
| September 30, 2024 | Ionic and Geometric Tuning of Magnetism: Paths to Next-Generation Hardware | Dr. Julius de Rojas, Oklahoma State University |
| October 7, 2024 | (topic: biophysics) | Dr. Meng Shen, CSU Fullerton |
| October 14, 2024 | (topic: condensed matter experiment) | Dr. Ezekiel Johnston-Halperin, Ohio State University |
| October 21, 2024 | (topic: quantum information theory) | Dr. Jonathan Gross, Google Quantum |
| October 28, 2024 | (topic: nuclear theory) | Dr. Zoltan Papp, CSU Long Beach |
| November 4, 2024 | (topic: particle physics) | Dr. Shirley Li, UC Irvine |
| November 18, 2024 | (topic: semiconductors) | Dr. Partha Dutta, United Semiconductor |
| December 2, 2024 | (topic: condensed matter theory) | Dr. Thomas Scaffidi, UC Irvine |
Previous Colloquia
The Colloquium Archive has the Colloquia from previous semesters.
| Date | Title | Speaker and Affiliation |
|---|---|---|
| September 16, 2024 | Spintronics with 2D Magnetic and Topological Materials: Outstanding Opportunities in van der Waals Heterostructures | Dr. Kelly Luo, USC |
| September 9, 2024 | Meet and Greet | All Physics Students and Faculty, CSU Long Beach |
Sponsors
We acknowledge with gratitude donations and support from the following present sponsors:
- H.E. and H.B. Miller and Family Endowment
- Benjamin Carter
- American Physical Society
- Anonymous
We also acknowledge with gratitude our past donors: The Forty-Niner Shops, Inc., The Northrop Grumman Foundation, Sandra Dana, Anonymous.
If you wish to support the Colloquium, please contact the colloquium coordinator or the department chair. Thank you!
