[seminar] Seminar T. Prokopec (NOVI TERMIN), utorak 22.12.2009. u 12h, IRB, predavaonica I krila

[Hrvoje Stefancic]

Poštovani kolege,

Proslijeđujem vam obavijest o novom terminu seminara koji će u utorak
22.12. u 12 h održati prof. Tomislav Prokopec sa Sveučilišta u Utrechtu.

Hrvoje Štefančić 

 
 
 
      INSTITUT "Ruder Boskovic"
      ZAVOD ZA TEORIJSKU FIZIKU
      Bijenicka c. 54, Zagreb, Hrvatska
 
 
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                     SEMINAR TEORIJSKE  FIZIKE
            (Zajednicki seminari Zavoda za fiziku PMF-a i
                 Zavoda za teorijsku fiziku  IRB-a)
 
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     Tomislav Prokopec, Utrecht University

    "Quantum backreaction in cosmology"

      Vrijeme:  22. prosinca 2009. (utorak) 12.00, c.t.
 
      Mjesto:  Institut Rudjer Boskovic, predavaonica I krila
 
      Sazetak: The problem of the quantum backreaction in expanding
spaces is an old,
as yet unresolved, question. In this talk I will consider the one-loop
backreaction of a massless scalar which couples to the Ricci scalar in
an expanding space with constant deceleration. I will show that the
infrared divergences, which generically plague the one loop stress
energy, can be removed by matching onto an earlier radiation era. An
insignificant backreaction occurs, unless the coupling to the Ricci
scalar is negative. Similar results hold for the graviton backreaction.


             
  
     Voditelj seminara:
     Hrvoje Štefančić (shrvoje at thphys.irb.hr)