STRINGY NONLOCAL COSMOLOGY

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STRINGY NON-LOCAL COSMOLOGY
I. Aref'eva Steklov
Mathematical Institute, Moscow

43rd Rencontres de Moriond 15-22 March,
2008
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STRINGY NON-LOCAL COSMOLOGY

• Cosmological constant
• why it is now so small
• Dynamical DE
• w lt - 1
• periodic crossing the w-1
  barrier

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STRINGY NON-LOCAL COSMOLOGY

• Cosmology FRW metric
• Start from the flat space-time
• Zero vacuum energy
• consistence theory w lt - 1
• periodic crossing the w-1
  barrier

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STRINGS in FLAT SPACE-TIME
Zero vacuum energy

• SUSY
• Sen mechanism Energy of the true vacuum
• is compensated by the
  brane tension
• (in classical and
  quantum levels)

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Sens mechanism
INFINITE number of FIELDS
STRINGS
Vacuum
Vacuum energy is negative

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D-brane String Field Theory

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Sens conjecture f1/4, I.A,
D.Belov,A.Koshelev,P.Medvedev, Nucl.Phys.(2000),
Ohmori (2001)
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Rolling for NSR GSO- Tachyon
AK-talk
I.A., L.Joukovskaya, A.Koshelev (2002)
Vladimirov, Ya.Volovich, D.Prokhorenko (2006)
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NSR Tachyon Gravity
New conjecture
Effective cosmological constant
I.A., astro-ph/0410443
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Nonlocal Dynamics in the Friedmann Metric
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Exact Solution for Toy Model
I.A., A. Koshelev, S.Vernov, PRD,2005,
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Hubble Parameter
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Nonlocal Models in Cosmology
I. Nonlocality in Matter (mainly string motivated)
I.A., astro-ph/0410443 I.A., L.Joukovkaya,
JHEP,05109 (2005) 087 I.A., A.Koshelev, JHEP,
07022 (2007) 041 I.A., L.Joukovskaya, S.Vernov,
JHEP 0707 (2007) 087, L.Joukovskaya, PR
D76(2007) 105007 arXiv0710.0404  G. Calcagni,
M.Montobbio,G.Nardelli JHEP, 0605 (2006) 012
0705.3043 0712.2237 N. Barnaby, T. Biswas, J.M.
Cline, hep-th/0612230
J.Lidsey, hep-th/0703007
Later cosmology Inflation
Bouncing solutions
II. Nonlocality in Gravity
Arkani-Hamed at al hep-th/0209227 Khoury,
hep-th/0612052 T.Biswas, A.Mazumdar, W.Siegel
hep-th/0508194 , G.Dvali, S. Hofmann, J Khoury,
hep-th/0703027, S.Deser, R.Woodard,
arXiv0706.2151S. UV - completion
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Summary
Assumptions
Universe as slowly decaying D3-brane
D-brane dynamics is described in the SFT
framework.
Dark Energy dynamics by Open String Tachyon
Back reaction by closed string dilaton
Nonlocal String Scalar Field Dynamics wlt-1
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String !
D-BRANE !
SFT !!!