[Assistant-faculty] Colloquium on Friday

[Danilo Marchesini <danilo marchesini tufts edu>]

Hi everyone,

this coming Friday at 3 pm Prof. Antonaldo Diaferio from the University of 
Turin (currently at Harvard-CfA for a sabbatical) will be our colloquium 
speaker (see title and abstract below). Let me know by the end of tomorrow 
(Thursday) if you would like to meet with him.

Thank you.

Best regards,
Danilo


"The Expansion History of the Universe: Myths and Facts"

Data from extensive surveys of high-redshift type Ia supernovae and 
gamma-ray bursts have usually been interpreted as a robust indication that 
the Universe expansion had an initial deceleration phase followed by the 
present acceleration phase. 
Because the solution based on the standard cosmological constant appears 
to be problematic, alternative cosmological models have been proposed 
under the assumption that this expansion history is well constrained by 
current data. I show that, when analysed with a proper Bayesian approach, 
this interpretation is not in fact as robust as usually assumed. 
I show that the data do not exclude an expansion history substantially 
different from the standard model. This result suggests that the range of 
possibilities of alternative theories of gravity and cosmology can be 
wider than usually conceived.

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Danilo Marchesini
Assistant Professor in Astronomy & Astrophysics
Tufts University
Robinson Hall
212 College Avenue
Medford, MA 02155 USA
Tel. 617-627-2756
Fax 617-627-3878
http://cosmos2.phy.tufts.edu/~danilo
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