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What powered the Big Bang? What happens at the edge of a Black Hole? What is Dark Energy? Nicholas White NASA Goddard Sp

National Aeronautics and Space Administration. What powered the Big Bang? What happens at the edge of a Black Hole? What is Dark Energy? Nicholas White NASA Goddard Space Flight Center . Exploring the beginning of Time!. Baby picture of the Universe from the

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What powered the Big Bang? What happens at the edge of a Black Hole? What is Dark Energy? Nicholas White NASA Goddard Sp

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  1. National Aeronautics and Space Administration What powered the Big Bang? What happens at the edge of a Black Hole? What is Dark Energy? Nicholas White NASA Goddard Space Flight Center

  2. Exploring the beginning of Time! Baby picture of the Universe from the Wilkinson Microwave Anisotropy Probe (WMAP)

  3. Using Supernovae to Measure the Expansion of the Universe

  4. The Dark Side of the Universe We do not know what 95% of the universe is made of! Solving this mystery may fundamentally change our view of the Universe and also may impact the standard model of particle physics!

  5. Exploring at the Edge of a Black Hole The Chandra X-ray Deep Field What happens close to a Black Hole?

  6. HST observes merging galaxies: • What happens to the central Black Holes? Chandra

  7. Gamma Ray Large Area Space Telescope GLAST will view along the relativistic jets from Black Holes “Cosmic accelerators” Search for the gamma-ray signature from the decay of dark matter particles Identify mysterious Compton GRO sources in the galactic plane Launch: Fall 2007 30-100 times improved sensitivity for high energy gamma rays GLAST is a joint NASA-DOE program, a pathfinder for the future where DOE and NASA interests overlap e.g. Dark Energy

  8. Hubble discovered the expanding Universe in 1929 Black holes found in our Galaxy and at the centers of most galaxies over the past three decades Evidence for an accelerating Universe was observed in 1998 Einstein’s Predictions Three startling outcomes of Einstein’s general relativity:  The expansion of the Universe (from a Big Bang)  Black holes  A Cosmological Constant acting against the pull of gravity Observations confirm these outcomes . . .

  9. Beyond Einstein is a series of NASA missions linked by powerful new technologies, and interlinked science goals to address: • What powered the Big Bang? • What happens at the edge of a Black Hole? • What is the mysterious Dark Energy pulling the Universe apart? Completing Einstein’s Legacy • Einstein’s legacy is incomplete, his theory fails to explain the underlying physics of the very phenomena his work predicted • Unification of Quantum Mechanics and General Relativity • We are on the threshold of a breakthrough comparable to Einstein’s discoveries one century ago . . .

  10. What Happens at the Edge of a Black Hole? Chandra deep image reveals Black Holes are ubiquitous Black Holes are a prediction of Einstein’s theory of General Relativity and can be used to test the theory in the strongest possible gravity fields Simulated Black Hole Image

  11. What Powered the Big Bang? Gravitational Waves Can Escape from Earliest Moments of the Big Bang Inflation (Big Bang plus 10-34 Seconds) light Big Bang plus 300,000 Years Now gravitational waves Big Bang plus 14 Billion Years

  12. What is Dark Energy? • In the standard cosmological framework the acceleration of the expansion of the Universe is caused by dark energy that makes up 70% of mass-energy density of the Universe in the current epoch • Several Possibilities: • Dark Energy constant in space & time (Einstein’s L) • Dark Energy varies with time • GR or standard cosmological model incorrect • ??????????? • There are no leading theoretical explanations for Dark Energy, to help guide us as to the right experiment to perform • Multiple approaches to measure the expansion of the universe are vital to look for inconsistencies • the answer may be where we least expect it!

  13. Beyond Einstein Program

  14. Black Holes as tests of GR X-Ray Spectroscopy • Japan-US ASCA satellite discovered iron lines near the event horizon of a black hole • Line exhibits a strong redshift and provides a unique probe of the inner regions of black holes Gravitational Radiation • Black hole binaries produce gravitational waves in all phases of their evolution • Test of GR in all three phases

  15. The Constellation-X Mission Constellation of X-ray telescopes • X-ray observatories must be in space! • Baseline design: four identical X-ray telescopes observing simultaneously • Orbiting the Sun at the 2nd Lagrange point (very stable conditions) • Allows X-ray imaging and high-resolution (R 300-3000) spectroscopy • 25-100 more sensitive than current high-resolution X-ray instruments • Major facility that will address: • Black Holes (evolution and tests of GR) • Dark Energy and Dark Matter • Open a new window of X-ray spectroscopy

  16. Constellation-X Science Goals • Black Holes • Observe matter spiraling into Black Holes & test the predictions of General Relativity • Study distant/faint sources to trace the evolution of Black Holes with cosmic time • Dark Matter and Dark Energy • Use clusters of galaxies to trace the amount and evolution of Dark Energy • Determine the spatial distribution of Dark Matter in galaxies and galaxy clusters • Origin of the Elements, New States of matter, Cosmic Feedback • Investigate the influence of Black Holes on galaxy formation • Search for the hot missing matter in the Cosmic Web • Study behavior of matter at extreme densities & magnetic fields using neutron stars

  17. Constellation-X: Probing Strong Gravity Iron line variability (from orbital motion of disk & reverberation effects) separates effects of Accretion disk physics and the Space-time geometry Requires 25-100 times increased collecting area and spectral resolution of Constellation-X to resolve motion on orbital timescale around black hole

  18. SNIa CMB Clusters Dark Energy from Cluster Mass Fraction New technique that uses the constancy of the ratio of the baryonic gas to dark matter fraction as a “standard candle” (Allen et al. 2005) • A large snapshot survey followed by deeper spectroscopic observations of several hundred relaxed clusters will achieve: • M=0.3000.007, =0.7000.047 • For flat evolving DE model, w0 = -1.000.15, w' = 0.000.27 Constraints are similar & complementary to SN Ia studies Rapetti and Vikhlinin

  19. LISA: Mission Overview • Measure time-varying strain in space-time by monitoring relative changes in 5 million kilometer long arms to a precision of 5 pico-meter RMS over 100s • Three spacecraft orbit the Sun in a triangular formation, 20° behind the Earth • The three arms: • Form an equilateral triangle • Are defined by six proof masses, located in pairs at the vertices of the triangle • Lasers at each end of each arm operate as transponders to range between proof masses • Are monitored interferometrically to achieve a measurement bandwidth from 3x10-5 to 1 Hz • Each spacecraft house two proof masses and protects them from disturbances by operating in a “drag-free” mode • LISA pathfinder in fall of 2009 to space qualify critical technologies Joint ESA-NASA project

  20. LISA: Science Goals and Sources Goals • Determine the role of massive black holes in galaxy evolution • Make precision tests of Einstein’s Theory of Relativity • Determine the population of ultra-compact binaries in the Galaxy • Probe the physics of the early universe Sources • Merging supermassive black holes • Merging intermediate-mass/seed black holes • Gravitational captures • Galactic and verification binaries • Cosmological backgrounds and bursts

  21. LISA: Supermassive Black Holes • LISA will see inspiraling supermassive black holes (~105 - 107 M) resulting from mergers of galaxies or pre-galactic structures out beyond z~20 • If most galaxies have had an SMBH-SMBH merger, then estimates range from ~0.1/yr to 10,000/yr • These are the strongest sources that LISA is likely to see with signal to noise rations of ~3,000 • LISA will determine: • Masses, spins and direction and absolute distance to the binary • Sampling of the history of galactic merger rates • Demographics: space density, mass distributions, spin distributions • Precision test of General Relativity in the dynamical, nonlinear gravity regime

  22. Gravitational Waves from Merging Black Holes Simulation by GSFC Numerical Relativity group (Baker, Centrella, Choi, Koppitz, van Meter), run on Project Columbia supercomputer at NASA/Ames

  23. Joint Dark Energy Mission (aka Dark Energy Probe) Determine the evolution of dark energy with time Constrain theories for the nature of dark energy Partnership between NASA and DOE Inflation Probe Study imprints of gravitational waves from inflation on the cosmic microwave background or large scale structure Determine when and how inflation occurred Black Hole Finder Probe To conduct a census of hidden black holes Gamma ray bursts as Cosmological Probes Einstein Probes Focused scientist led missions that each address a single high priority science topic, with the implementation approach selected by competition

  24. Joint Dark Energy Mission (JDEM) Solving the riddle of Dark Energy is one of the pressing issues in science today The solution may lead to a revolution in physics and astronomy, and take us into a new “Post-Einstein” era! The Einstein Probe called Joint Dark Energy Mission (JDEM) will make measurements to determine how Dark Energy evolves JDEM to be undertaken as a partnership between NASA and DOE Science technique and mission approach to be selected by competition, concept studies for JDEM have been solicited and selections later this year

  25. Inflation Probe Gravitational waves from the Big Bang may be detected directly by a future challenging gravitational wave observatory: the Big Bang Observer (BBO) Before we invest in the BBO there is an indirect way to search for these waves Gravitational waves leave a distinctive imprint on the polarization pattern of Cosmic Microwave Background An Einstein Probe to search for this polarization is one possible approach

  26. Black Holes Finder Probe Most Black Holes at the center of galaxies are thought to be hidden behind an inner thick disk of material • Hard X-rays can penetrate this torus and the Black Hole Finder Einstein Probe will make first sensitive hard X-ray all-sky census and is expected to find thousands of “hidden” Black Holes

  27. National Research Council Decadal Survey: “Astronomy and Astrophysics in the New Millennium” (2001) National Academies Report: “Eleven Science Questions for the new century” (2003) OSTP-commissioned interagency working group report: “Physics of the Universe” (2004) Endorsements for BE Science and Missions The Beyond Einstein science topics and missions have been rated very highly by several national committees  Nobel Prize in Physics in 2002 from the Royal Swedish Academy of Sciences to Riccardo Giacconi “for pioneering contributions to astrophysics, which have led to the discovery of cosmic X-ray sources”  Other related Physics Nobel Prizes: Hulse & Taylor (1993); Fowler & Chandrasekhar (1983); Penzias & Wilson (1978); Hewish (1974); Hess (1936); Einstein (1921)

  28. Go to Web Site for more information http://universe.nasa.gov

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