Workshop on Transplanckian Physics

1
Workshop on Transplanckian Physics

• Uppsala, 24-26 october 2002

http//www.teorfys.uu.se/PEOPLE/domert/nordic/inde
x.html
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Review ofStandard Big Bang Cosmology
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Standard BB Cosmology

• Hubble Law (20s) and redshift
• CMBR (60s and today)
• Nucleosynthesis
• Age of the Universe
• Expansion Models
• Dark Matter/Energy
• Other models steady state model,

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History of the Universe (with Inflation)
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History of the Universe w/o Inflation
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Adiabatic expansion
In Big Bang Cosmology the universe expands and
cools. At the origin, it was infinitely hot and
dense.
http//www.astro.utoronto.ca/mcclure/problems/evo
lution.html
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Big Bang Theory
Why did people come up with the Big Bang Theory?
The first evidence was found by Edwin Hubble in
the 1920's. The further away a galaxy, the
faster it moves away.
http//www.astro.utoronto.ca/mcclure/problems/why
.html
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Hubble time
Hubble Time 1 Hubble Constant. It's the time
it would take space to expand from a point to
yield present galaxy separations -- the age of
the universe!
A Hubble Constant of 72 km/s/Mpc means a Hubble
Time of 14 Gyrs. The universe's gravity is
slowing its expansion. Thus, the Hubble Constant
should have been larger in the past.
http//www.astro.utoronto.ca/mcclure/problems/tim
e.html
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CMBR isotropy
(Penzias and Wilson, 1965)
http//www.astro.utoronto.ca/mcclure/problems/pen
zias.html
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CMBR anisotropy (MAXIMA)
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CMBR angular power spectrum
Dipole anisotropy (Conklin, 1969)
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CMBR Anisotropy
http//www.astro.ucla.edu/wright/CMB-DT.html
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Nucleosynthesis
Atoms didn't form until after the universe cooled
enough. The Big Bang Theory predicts the
fractions of different elements.
http//www.astro.utoronto.ca/mcclure/problems/nuc
leo.html
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Dark matter from galaxy angular velocity
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SBB References

• The Early Universe - Kolb, Turner
• CMBR and Large-Scale structure - Liddle, Lyth
• Inflation and the theory of cosmological
  perturbations - Riotto
• Other references at http//www.teorfys.uu.se/PEOP
  LE/domert/nordic/index.html

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Why Transplanckian Physics?

• Standard BB cosmology presents some open issues
• The Flatness Problem
• The Entropy Problem
• The Horizon Problem
• Structure formation CMBR inhomogeneities
• matter/antimatter asimmetry, dark matter, ...

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Workshop on Transplanckian Physics

• Uppsala, 24-26 october 2002

http//www.teorfys.uu.se/PEOPLE/domert/nordic/inde
x.html
18
Program
U. Danielsson Can Planck see transplanck? O.
Elgaroey Neutrino properties from the 2dF Galaxy
Redshift Survey M. Giovannini The pre-big bang
scenario confronts observations D.
Grasso Cosmology with gravitational wave
detectors F. Hassan 1. Introduction to the Theory
of Cosmological Perturbations 2. Introduction
to the Trans-Planckian Problem in Inflationary
Cosmology A. Jokinen Baryogenesis through
Affleck-Dine mechanism N. Kaloper Inflation and
Short-Distance Physics E. K.Vakkuri Cosmological
toy models in string theory M. Laine Higher
dimension induced domain wall defects in our
world J. Niemeyer Models and Signatures of Short
Distance Physics in Inflation S. Räsänen The
ekpyrotic scenario/cyclic model status report M.
Sloth Transplanckian effects in inflationary
cosmology and the modified uncertainty
principle A. Starobinsky Trans-Planckian particle
creation now and in the past I. Wehus Scalar
field potential in 5-dimensional Kaluza-Klein
theory
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Partecipants (54)
Morad Amarzguioui University of Oslo, Andreas
Bredthauer University of Uppsala (UU), Torsten
Bringmann University of Stockholm (SU), Trygve
Buanes University of Bergen, Poul Damgaard
Nordita, Ulf Danielsson (UU), , Daniel Domert
(UU), Joakim Edsjö (SU), Oeystein Elgaroey
Nordita, Johan Engquist (UU), Martin Eriksson
(SU), Lisa Freyhult (UU), Massimo Giovannini
University of Lausanne, Ariel Goobar (SU), Dario
Grasso Scuola Normale Superiore, Pisa Anne Green
(SU), James Gregory (UU), Christofer Gunnarsson
(SU), Michael Gustafsson (SU), Fawad Hassan
(SU), Troels Haugbølle University of Copenhagen,
Janne Högdahl University of Helsinki (HIP), Asko
Jokinen (HIP), Nemanja Kaloper Stanford, Shinsuke
Kawai (HIP), Esko Keski-Vakkuri (HIP), Christiaan
Korthals-Altes CERN, Fredric Kristiansson (UU),
Mikko Laine CERN/TH, Martin Lubcke (UU), Keizo
Matsubara (UU), Vesa Muhonen (HIP), Jens Niemeyer
Max-Planck-Institute, Martin Olsson (UU), Silvio
Orsi KTH, Ioanna Pappa (SU), Jonas Persson (UU),
Narit Pidokrajt (SU), Peter Rajan (UU), Finn
Ravndal University of Oslo, Hector Rubinstein
(SU), Kari Rummukainen (HIP), Syksy Räsänen
Oxford University, Mia Schelke (SU), Martin Sloth
(HIP), Mikael Smedbäck (UU), Alexei Starobinsky
Landau Institute, Riccardo Sturani (HIP), Kristel
Torokoff (UU), Konrad Tywoniuk University of
Oslo, Alexander Vereshagin University of Bergen,
Antti Väihkönen (HIP), Jussi Väliviita (HIP),
Ingunn Kathrine Wehus University of Oslo
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Theories vs Experiments (1)

• Theories / Toy models
• Standard Big Bang Cosmology (starting point)
• Inflation
• Theory of Cosmological Perturbations
• Pre-Big Bang scenario
• Ekpyrotic scenario / cyclic model
• ...

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Theories vs Experiments (2)

• Typical signatures
• Look for theories with a good footprint
• Experiments
• Gravitational waves detectors
• Supernova Project
• CMBR survey
• Neutrino studies
• UHECR
• PAMELA, ...

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Some formalism Inflation
FRW line element
Friedmann eq.
Einstein eq.
These numbers are like George Bush military
budget...
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Slow-roll Inflation
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Theory of Cosmological Perturbations

• Standard Big Bang formalism theory
• Perturbation theory
• Density inhomogeneities amplified by gravity (ex.
  ??/? 10-5 after 300000 yrs may explain
  structure formation)

Riotto, hep-ph/0210162 Inflation and the theory
of cosmological perturbations
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Trans-planckian Problem in Inflationary Cosmology
In most current models of inflation, the period
of exponential expansion lasts so long that at
the beginning of inflation, scales of
cosmological interest today had a physical
wavelength much smaller than the Planck length,
and the theories used to compute the spectrum of
fluctuations are known to break down on these
scales.
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The pre-big bang scenario confronts observations
Massimo Giovannini, University of Lausanne
Abstract The key features of the pre-big bang
scenario will be presented in light of its
possible phenomenological relevance. Recent
developments will also be discussed with
particular attention to possible implications for
CMB physics and relic GW backgrounds. A personal
view of the speaker on the future (possible)
directions of this scenario will also be given.
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Pre Big-bang Scenario
Inflation after BB
Inflation before BB
Figures from http//www.ba.infn.it/gasperin/
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Cosmology with gravitational wave detectors
Dario Grasso, Scuola Normale Superiore, Pisa
Abstract The new generation of gravitational
waves detectors under construction/project may be
able to detect stochastic backgrounds of
cosmological origin. A short panoramic on the
most promising sources and the characteristics of
the expected signals will be given.
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GW Production

• GW background from amplification of vacuum
  fluctuations
• Standard inflation
• Pre-Big Bang cosmology
• Other models
• Known astrophysical sources
• Noise (unresolved astrophysical sources)
• On Earth Seismic noise

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GW from a Pre-BB Model
http//www.ba.infn.it/gasperin/
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VIRGO Sensitivity
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VIRGO
http//wwwlapp.in2p3.fr/virgo/gwf.html
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Affleck-Dine Mechanism

• Mechanism to explain matter-AM asimmetry w/o
  assuming baryon number violation
• A potential is generated by SUSY breaking and
  non-renormalizable terms in the superpotential
• The condensate eventually decays either directly
  into fermions or into non-topological solitons
  called Q-balls (robust objects with long lifetime)

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Ekpyrotic Scenario

• One visible 3-D brane one 3-D hidden brane in a
  11-D space
• Brane oscillations induce energy transfer (BB in
  our brane)
• Old, new cyclic scenario (all 2001)

Figures from http//www.sciencenews.org/20010922
/bob9.asp
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Ekpyrotic Scenario (2)

• Old scenario (visible brane2) March 2001
• New scenario (visible brane1) August 2001
• Cyclic scenario (continuous process) November
  2001

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Transplanckian effects in inflationary cosmology
and the modified uncertainty principle
Martin Sloth, University of Helsinki
Abstract Both the modified uncertainty
principle and modified dispersion relations as a
way of modeling quantum gravity within inflation,
has been investigated as sources of
trans-Planckian effects in the CMB. We will
explain how one can naturally build a field
theory on deSitter space such that the two
effects arise as two sides of the same coin. In
addition one is lead to a "trans-Planckian
damping", which is an exponential damping of
ultra high energy modes. We will also discuss the
effect of the trans-Planckian damping on the
evolution of density perturbations.
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The Stringy Uncertainty Principle
Hyphotesis there is a minimum resolution ?xmin
?½
J. Niemeyer, Models and Signatures of short
distance physics in inflation
M.Sloth, Transplanckian effects in inflationary
cosmology and the modified uncertainty principle
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Sentences of the Day
If a matematician would look at what we are
doing, he wouldnt be happy! They are never
happy
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Sentences of the Workshop
An expert is a man who has made all the mistakes
which can be made in a very narrow field. Niels
Bohr
My goal is simple. It is complete understanding
of the universe, why it is as it is and why it
exists at all. Stephen Hawking
This isn't right. This isn't even wrong.
Wolfgang Pauli
For those who want some proof that physicists
are human, the proof is in the idiocy of all the
different units which they use for measuring
energy Richard P. Feynman
If you wish to make an apple pie truly from
scratch, you must first invent the universe.
Carl Sagan
http//www.teorfys.uu.se/PEOPLE/domert/nordic/inde
x.html
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Penrose Diagrams
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Minkowski space
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Penrose Diagram
A Penrose Diagram is a spacetime diagram that
shows the global causal structure of a
spacetime.  As in usual diagrams, light rays
travel in 45 angles. Distances on a graphics
are not proportional to physical distances.
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Penrose Diagram (Sch. BH)
Causal structure of a spherically symmetric
"Schwarzchild" type black hole. Once inside the
event horizon, all physical trajectories
inevitably lead to the singularity.