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Dr. Levon Pogosian

Simon Fraser University

Date of Live Presentation: tba
Location: tba


The Accelerating Universe: Lambda, W and Beyond


Over the past 100 years, our understanding of the universe evolved from assuming it to be static, to accepting that it is expanding and, more recently, finding that the expansion is accelerating. While cosmic acceleration is well-established, the nature of Dark Energy causing it remains unknown. A universe dominated by a cosmological constant (Lambda) and dark matter has been cosmologists’ working model of choice for nearly two decades. However, the value of Lambda poses a serious theoretical challenge, exposing a gap in our understanding of how the vacuum energy is supposed to gravitate. There are also hints from observations that the latest data may prefer dark energy to be dynamical. I will review the history leading to the discovery of cosmic acceleration, as well as the latest status of Lambda and some of the alternative theories that are being developed. I will then discuss how upcoming astronomical surveys of large scale structure will dramatically improve our ability to test Lambda and its alternatives.

Short bio

Levon Pogosian received his PhD from Case Western Reserve University in Cleveland, Ohio, and held postdoctoral positions at Imperial College London, Tufts University and Syracuse University. He joined the Physics Department at SFU in 2006 to co-found a theoretical cosmology group. His research interests include searching for signatures of cosmic strings and primordial magnetic fields in the cosmic microwave background, and developing new ways of testing laws of gravity using cosmological data.

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