Cornell University

During the spring semester, in-person concerts, events and lectures that involve outside guests will not be held, per the university’s COVID-19 travel and visitor policy.

Cornell Department of Astronomy & Space Sciences Spring 2021 Colloquium Series

Thursday, March 18, 2021 at 4:00pm to 5:00pm

Virtual Event

"The Josephine Lawrence Hopkins Foundation Colloquium":

"The Degree of Fine-Tuning in our Universe -- and Others "

Abstract: The fundamental constants of nature must fall within a 

range of values in order for the universe to develop structure and

ultimately support life. This talk considers current constraints on

these quantities and assesses the degree of tuning required for the

universe to be viable. In the realm of particle physics, the relevant

parameters are the strengths of the fundamental forces and the

particle masses.  Additional astrophysical parameters include the

cosmic energy density, the cosmological constant, the abundances of

ordinary matter and dark matter, and the amplitude of primordial

density fluctuations. These quantities are constrained by the

necessity that the universe lives for a long time, emerges from its

early epochs with an acceptable chemical composition, and successfully

produces galaxies. On smaller scales, stars and planets must be able

to form and function. The stars must have sufficiently long lifetimes

and hot surface temperatures.  We also consider potential fine-tuning

related to the triple alpha reaction that produces carbon, the case of

unstable deuterium, and the possibility of stable diprotons. For all

of these issues, the goal is to delineate the range of parameter space

for which universes can remain habitable. 


Dial-In Information

The colloquia are held every Thursday afternoon 4-5 pm. The public is welcome. To view via Zoom, please contact Monica Carpenter ( or Jason Jennings ( for the link.

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Contact E-Mail

Contact Name

Monica Carpenter

Contact Phone



Fred Adams

Speaker Affiliation

University of Michigan

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