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

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Tommaso Treu

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.

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Fall 2024 - Spring 2025 imaging of supernovae
Fig. Fall 2024 - Spring 2025 Imaging.

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

Fall 2024 Colloquia
DateTitleSpeaker and Affiliation
September 23, 2024The "Hubble Tension": Measuring the Expansion History of the Universe with Gravitational Time DelaysDr. Tommaso Treu, UCLA
September 30, 2024Ionic and Geometric Tuning of Magnetism: Paths to Next-Generation HardwareDr. 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.

Fall 2024 Previous Colloquia
DateTitleSpeaker and Affiliation
September 16, 2024Spintronics with 2D Magnetic and Topological Materials: Outstanding Opportunities in van der Waals HeterostructuresDr. Kelly Luo, USC
September 9, 2024Meet and GreetAll 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!