1 1 The Darkness of the Universe: The Darkness of the Universe: The Heart of Darkness Eric Linder Lawrence Berkeley National Laboratory.

Slides:



Advertisements
Similar presentations
The Nuts and Bolts of Inflation Richard Barrett. Dark Energy SeminarGlasgow 29/11/2003 Inflation What is inflation? What is dark energy? Why was inflation.
Advertisements

1 1 Dissecting Dark Energy Eric Linder Lawrence Berkeley National Laboratory.
P ROBING SIGNATURES OF MODIFIED GRAVITY MODELS OF DARK ENERGY Shinji Tsujikawa (Tokyo University of Science)
CMB but also Dark Energy Carlo Baccigalupi, Francesca Perrotta.
The physics of inflation and dark energy 2.6 Acceleration in scalar field models Hubble “drag” Potential  V()V() Canonical scalar fields: If thekineticenergy.
Dark Energy and Extended Gravity theories Francesca Perrotta (SISSA, Trieste)
University of Texas at San Antonio Arthur Lue Dark Energy or Modified Gravity?
1 1 Hidden Dimensions, Warped Gravity, Dark Energy Eric Linder UC Berkeley Lawrence Berkeley National Laboratory.
Non-linear matter power spectrum to 1% accuracy between dynamical dark energy models Matt Francis University of Sydney Geraint Lewis (University of Sydney)
Cosmological Structure Formation A Short Course
L. Perivolaropoulos Department of Physics University of Ioannina Open page.
Quintessence and the Accelerating Universe
Álvaro de la Cruz-Dombriz Theoretical Physics Department Complutense University of Madrid in collaboration with Antonio L. Maroto & Antonio Dobado Different.
The New Cosmology flat, critical density, accelerating universe early period of rapid expansion (inflation) density inhomogeneities produced from quantum.
Lecture 23 Models with Cosmological Constant ASTR 340 Fall 2006 Dennis Papadopoulos Chapter 11 Problems Due 12/5/06.
History of the Universe - according to the standard big bang
Complementary Probes ofDark Energy Complementary Probes of Dark Energy Eric Linder Berkeley Lab.
COSMO 2006, Lake Tahoe 9/28/2006 Cuscuton Cosmology: Cuscuton Cosmology: Dark Energy meets Modified Gravity Niayesh Afshordi Institute for Theory and Computation.
Coupled Dark Energy and Dark Matter from dilatation symmetry.
L. Perivolaropoulos Department of Physics University of Ioannina Open page.
1 1 Eric Linder University of California, Berkeley Lawrence Berkeley National Lab Course on Dark Energy Cosmology at the Beach 2009 JDEM constraints.
THE GRACEFUL EXIT FROM INFLATION AND DARK ENERGY By Tomislav Prokopec Publications: Tomas Janssen and T. Prokopec, arXiv: ; Tomas Janssen, Shun-Pei.
Chapter 26: Cosmology How big is the universe? How long has it been around and how long will it last?
1 1 The Darkness of the Universe Eric Linder Lawrence Berkeley National Laboratory.
The Hunting of the Dark Energy and On Beyond Lambda Eric Linder Cosmology Teach-In 26 June 2003.
Structure formation in dark energy cosmology La Magia, April 2005.
Large distance modification of gravity and dark energy
Dark Energy and Modified Gravity IGC Penn State May 2008 Roy Maartens ICG Portsmouth R Caldwell.
Modified (dark) gravity Roy Maartens, Portsmouth or Dark Gravity?
Cosmology: The Study of the Universe as a Whole Physics 360 Geol 360 Astronomy John Swez.
The Theory/Observation connection lecture 1 the standard model Will Percival The University of Portsmouth.
1 1 Eric Linder University of California, Berkeley Lawrence Berkeley National Lab Seeing Darkness: The New Cosmology.
Dark Energy The first Surprise in the era of precision cosmology?
1 1 Eric Linder 24 July 2013 Chasing Down Cosmic Acceleration UC Berkeley & Berkeley Lab Institute for the Early Universe, Korea.
COSMOLOGY SL - summary. STRUCTURES Structure  Solar system  Galaxy  Local group  Cluster  Super-cluster Cosmological principle  Homogeneity – no.
1 1 Eric Linder University of California, Berkeley Lawrence Berkeley National Lab Interpreting Dark Energy JDEM constraints.
Cosmological structure formation and dark energy Carlo Baccigalupi Heidelberg, May 31, 2005.
The dark universe SFB – Transregio Bonn – Munich - Heidelberg.
The Birth of the Universe. Hubble Expansion and the Big Bang The fact that more distant galaxies are moving away from us more rapidly indicates that the.
Expansion of the Universe Natural consequence of the basic field equations of the General Theory of Relativity (GTR) When GTR was first developed in the.
1 1 The Darkness of the Universe Eric Linder Lawrence Berkeley National Laboratory.
The Fate of the Universe
Dark Energy Expanding Universe Accelerating Universe Dark Energy Scott Dodelson March 7, 2004.
Michael Doran Institute for Theoretical Physics Universität Heidelberg Time Evolution of Dark Energy (if any …)
PHY th century cosmology 1920s – 1990s (from Friedmann to Freedman)  theoretical technology available, but no data  20 th century: birth of observational.
General Relativity Physics Honours 2008 A/Prof. Geraint F. Lewis Rm 560, A29 Lecture Notes 10.
Cosmological structure formation and dark energy Carlo Baccigalupi Madrid, November 15, 2005.
1 1 Dark Energy: Extending Einstein Eric Linder University of California, Berkeley Lawrence Berkeley National Lab.
1 1 The Darkness of the Universe: The Darkness of the Universe: Mapping Expansion and Growth Eric Linder Lawrence Berkeley National Laboratory.
Hypothesis Scalar Field is the Dark Matter and the Dark Energy in the Cosmos, i.e. about 95% of the matter of the Universe. Scalar Field is the Dark Matter.
Theoretical Aspects of Dark Energy Models Rong-Gen Cai Institute of Theoretical Physics Chinese Academy of Sciences CCAST, July 4, 2005.
Cosmology and Dark Matter III: The Formation of Galaxies Jerry Sellwood.
Dark Energy in the Early Universe Joel Weller arXiv:gr-qc/
1 1 Dark Energy with SNAP and other Next Generation Probes Eric Linder Berkeley Lab.
1 1 The Darkness of the Universe: The Darkness of the Universe: Acceleration and Deceleration Eric Linder Lawrence Berkeley National Laboratory.
Quintessence Dark Energy & Acceleration of the Universe B URIN G UMJUDPAI The Tah Poe Academia Institute for Theoretical Physics & Cosmology Department.
The Fate of the Universe What property determines the ultimate fate of the universe?
Lecture 23: The Acceleration of the Universe Astronomy 1143 – Spring 2014.
Discovering the Universe Eighth Edition Discovering the Universe Eighth Edition Neil F. Comins William J. Kaufmann III CHAPTER 18 Cosmology Cosmology.
ETSU Astrophysics 3415: “The Concordance Model in Cosmology: Should We Believe It?…” Martin Hendry Nov 2005 AIM:To review the current status of cosmological.
N-body Simulations and Gravitational Lensing with Dark Energy Beyond Einstein Meeting, May 13, 2004.
The Nature of Dark Energy David Weinberg Ohio State University Based in part on Kujat, Linn, Scherrer, & Weinberg 2002, ApJ, 572, 1.
Dark Energy: Hopes and Expectations Mario Livio Space Telescope Science Institute Mario Livio Space Telescope Science Institute.
Machian General Relativity A possible solution to the Dark Energy problem and an alternative to Big Bang cosmology ? Robin Booth Theoretical Physics Imperial.
Dark Matter, Dark Energy
University of California, Berkeley Lawrence Berkeley National Lab
Recent status of dark energy and beyond
Expansion of the Universe
Quantum Spacetime and Cosmic Inflation
Presentation transcript:

1 1 The Darkness of the Universe: The Darkness of the Universe: The Heart of Darkness Eric Linder Lawrence Berkeley National Laboratory

2 2 New Frontiers Beyond Einstein: What happens when gravity is no longer an attractive force? Scientific American Discovery ( SCP,HiZ 1998 ): 70% of the universe acts this way! Fundamentally new physics. “ ‘Most embarrassing observation in physics’ – that’s the only quick thing I can say about dark energy that’s also true.” -- Edward Witten

3 3 The world is w(z) Don’t care if it’s braneworld, cardassian, vacuum metamorphosis, chaplygin, etc. Simple, robust parametrization w(a)=w 0 +w a (1-a) Braneworld [DDG] vs. (w 0,w a )=(-0.78,0.32) Vacuum metamorph vs. (w 0,w a )=(-1,-3) Also agree on m(z) to 0.01 mag out to z=2

4 4 Our Tools Expansion rate of the universe a(t) ds 2 =  dt 2 +a 2 (t)[dr 2 /(1-kr 2 )+r 2 d  2 ] Einstein equation (å/a) 2 = H 2 = (8  /3)  m +  H 2 (z) = (8  /3)  m + C exp{  dlna [1+w(z)]} Growth rate of density fluctuations g(z) = (  m /  m )/a Poisson equation  2  (a)=4  Ga 2  m = 4  G  m (0) g(a)

5 5 Revealing Physics Time variation w(z) is a critical clue to fundamental physics. Modifications of the expansion history = w(z). But need an underlying theory -  ? beyond Einstein gravity? Growth history and expansion history work together. w 0 =-0.78 w a =0.32 cf. Lue, Scoccimarro, Starkman Phys. Rev. D69 (2004) for braneworld perturbations

6 6 Testing the Framework Extensions to gravitation E.g. scalar-tensor theories: f/2  -  (  )  ;   ;  -V Take linear coupling to Ricci scalar R: f/  = F R Allow nonminimal coupling F=1/(8  G)+  2 R-boost (note R  0 in radiation dominated epoch) gives large basin of attraction: solves fine tuning yet w ≈ -1. [Matarrese,Baccigalupi,Perrotta 2004] But growth of mass fluctuations altered: S  0 since G  1/F.

7 7 Scalar-Tensor Gravity Consider a general linear coupling R/(8  G)  F(  ) R Today, have F = 1/(8  G) and Jordan-Brans-Dicke parameter  JBD = F/F  2 Can treat as coupled scalar-tensor theory in physical = Jordan frame Or as separated scalar+tensor theory in spin = Einstein frame

8 8 Scalar-Tensor Gravity In terms of  H 2, following Baccigalupi, Matarrese, & Perrotta (3/8  G)  H 2 = V + (1/2)F  2 (q-1)(q+5) +3H 2 [F-1/(8  G)] Can show that effective Equation of State 1+w ~ 1/  JBD w = dw/d ln a ~ 1/  JBD Note  JBD > (or is it?) so “extended quintessence” has attractor solution to GR, and acts like cosmological constant. However, has non-vanishing anisotropic stress, so may affect structure growth.

9 9 Lambda, Quintessence, or Not? Many models asymptote to w=-1, making distinction from  difficult. Can models cross w=-1? (Yes, if w<-1 exists.) All models match CMB power spectrum for  CDM

10 Dark Entropy Holographic principle relates entropy to horizon area (Susskind 1994; Fischler & Susskind 1995) Conjecture: use horizon area, i.e. entropy, as physical basis. Key quantity is not energy in volume, but entropy on horizon. No physical dark energy, rather dark entropy S~H -2. Invert to solve for expansion dynamics H 2 (derived Friedmann equation). Anything interesting? Linder hep-th/

11 Cosmic Dynamics H HH w w tot Dark entropy always accelerates: w=-1/ Dynamical behaviors can be nonmonotonic! Hubble diagram, growth history can lie within 0.02 mag, 15% in growth of  CDM. Acceleration motivated by physical principle (not ad hoc addition to Friedmann equation). First steps look intriguing. Benchmark -- model clearly distinct from . No limit in phase space where becomes , unlike field theory models.

12 Dark Energy Surprises There is still much theoretical work needed! Dark energy is… Dark Smooth on cluster scales Accelerating Maybe not completely! Clumpy in horizon? Maybe not forever! It’s not quite so simple!

13 Heart of Darkness Is dark energy dark – only interacts gravitationally? Self interaction: pseudoscalar quintessence Coupling to matter: Chaplygin gas Leads to 5 th force: limited by lab tests Unify dark energy with dark matter?  Distorts matter power spectrum: ruled out unless within of  Coupling to gravitation: Scalar-tensor theories = Extended quintessence Can clump on subhorizon scales Can “turn on” from nonlinear structure formation?! Higher dimension gravity: Scalaron quintessence Can be written in terms of scalar-tensor and w eff Sandvik et al The horror!

14 Dark Energy Dreaming Direct detection? (Dark energy in solar system = 3 hours of sunlight). Variations of fundamental constants: lab and accelerator and universe. CMB: cosmic variance, 0.003% of present age (2 cells) Direct acceleration? Redshift drift (Sandage 1959; Linder 1991,1997) dz=10 -8 over 100 years

15 What if Our Eyes Saw Dark (Energy)? The night sky is dark in photons, implying a finite past (Big Bang). The sky is bright in  (dark energy density dominates), implying an infinite future. Will this turn out to be as significant a discovery as the Big Bang?

16 Hunting Dark Energy w´ is the 1 st step for fundamental physics, on or beyond . w´=dw(z)/dlna| z=1 =w a /2 goes a long way toward w(z). w(z) is a very general “language” for the underlying physics. In our hunt for the dark energy, the data decides how to go on beyond . Require precision + complementarity + systematics control. Expansion history and growth history (e.g. SN+WL) work well together.

17 Beyond Dark Energy Determine not only dark energy parameters, but test the cosmology framework – alternative gravitation, higher dimensions, etc.

18 Present Day Inflation Map the expansion history precisely and see the transition from acceleration to deceleration.

19 Density History of the Universe Map the density history precisely, back to the matter dominated epoch.

20 Frontiers With every new discovery in physics, there is less of a dividing line between Particle Physics and Astrophysics. Inflation: Particle accelerators GUT scale physics Early universe Origin of matter, gravitational waves Dark Energy: vacuum energy, quantum fields, extra dimensions acceleration of the universe fate of the universe Dark Matter: LHC, direct detection galaxy clusters, gravit’l lensing

21 Frontiers With every new discovery in physics, there is less of a dividing line between Particle Physics and Astrophysics. Inflation: Particle accelerators GUT scale physics Early universe Origin of matter, gravitational waves Dark Energy: vacuum energy, quantum fields, extra dimensions acceleration of the universe fate of the universe Dark Matter: LHC, direct detection galaxy clusters, gravit’l lensing “SUSY in the sky” “Tevatron  Planck-otron” “Quantum Cosmology?”

22 The Next Physics The Standard Model gives us commanding knowledge about physics -- 5% of the universe (or 50% of its age). What is dark energy? Will the universe expansion accelerate forever? Does the vacuum decay? Phase transitions? How many dimensions are there? How are quantum physics and gravity unified? What is the fate of the universe? That 5% contains two fundamental forces and 57 elementary particles. What will we learn from the dark sector?! How can we not seek to find out?

23 Frontiers of the Universe Breakthrough of the Year 1919 Cosmology holds the key to new physics in the next decade Let’s find out!