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Slide 1: 

Dr. Anita Krishnamurthi University of Maryland / NASA GSFC National Aeronautics and Space Administration

Slide 2: 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 2

Late 19th Century . . . : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 3 Late 19th Century . . . Many physicists were certain that our understanding of the physical Universe was almost complete But – there remained a few little problems:  The speed of light seemed to be independent of the reference frame in which it was measured  Hot objects predicted to radiate infinite amounts of energy (clearly contradicted by experiments! “UV catastrophe”) Solutions revolutionized physics – Theory of Relativity and Quantum Mechanics were born!

Late 19th Century . . . : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 4 Late 19th Century . . . Many physicists were certain that our understanding of the physical Universe was almost complete But – there remained a few little problems:  The speed of light seemed to be independent of the reference frame in which it was measured  Hot objects predicted to radiate infinite amounts of energy (clearly contradicted by experiments! “UV catastrophe”) Solutions revolutionized physics – Theory of Relativity and Quantum Mechanics were born!

The Theory of Relativity : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 5 The Theory of Relativity GR is a very rich and mathematically complex theory  many surprises in store! Einstein changed the way we think of the Universe: The speed of light is the ultimate speed limit. Time passes more slowly for observers traveling at high speeds or near a massive body. “Gravity” is the manifestation of curvature of space-time.

Einstein’s “Predictions” : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 6 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 . . .

Evidence for the Expanding Universe : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 7 Evidence for the Expanding Universe We know about Expanding Universe & Big Bang from: Hubble’s discovery of red-shifted galaxies. Abundances of the light elements. Penzias & Wilson discovery of 3 K background. Big Bang alone doesn’t quite produce the Universe we see. Inflation produces a flat universe. A growth spurt that stretches sub-atomic scales to astronomical scales. Produces the fluctuations that lead to galaxies. So – what powered the Big Bang and Inflation??

Evidence for Black Holes : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 8 Evidence for Black Holes Black holes come in 3 flavors Stellar (5 - 15 solar masses) [Evident in X-ray Binary Systems] Super-massive (Million-Billion solar masses) [In centers of galaxies] Intermediate (Thousand solar masses) [Within galaxies, but not in center] Abundant Observations and Evidence We measure masses (e.g from binary systems). We observe radiation from gaseous disks surrounding the black hole.

Slide 9: 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 9 Black hole at the Milky Way’s Center

Large Magellanic Cloud : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 10 Large Magellanic Cloud

Evidence for Dark Energy : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 11 Evidence for Dark Energy SN Ia are more distant than expected spacetime has expanded more than expected. Dark Energy revealed itself in a survey of supernovae in the late 1990’s. We can use certain types of supernovae to determine distances to galaxies. We then compare those distances with the galaxy’s velocity.

Completing Einstein’s Legacy : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 12 Completing Einstein’s Legacy Einstein’s legacy is incomplete – we do not understand the underlying physics of the very phenomena that came out of his theories. We are on the threshold of a breakthrough comparable to Einstein’s discoveries one century ago . . .

Slide 13: 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 13 Chandra deep image reveals Black Holes are ubiquitous Each point of x-ray light is a Black Hole! What Happens at the Edge of a Black Hole?

Black Hole Physics : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 14 Japan-US ASCA satellite studied iron gas orbiting 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 X-Ray Spectroscopy Black Hole Physics

Black Hole Physics : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 15 Black hole binaries produce gravitational waves in all phases of their evolution Test of GR in all three phases Gravitational Radiation Black Hole Physics

Gravitational Wave Astronomy : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 16 Gravitational Wave Astronomy Black holes, neutron stars, and white dwarfs orbiting each other emit gravitational waves Gravitational radiation from black hole mergers can be used to test General Relativity

Visualization of black hole merger : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 17 Visualization of black hole merger

What is Dark Energy? : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 18 A surprising recent discovery has been the discovery that the expansion of the Universe is accelerating. Implies the existence of dark energy that pushes the Universe apart. Dark Energy maybe related to Einstein’s Cosmological Constant; its nature is a mystery. What is Dark Energy?

What is Dark Energy? : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 19 Solving this mystery may lead to a revolution in physics and astronomy, and take us into a new “Post-Einstein” era! We do not know what 95% of the universe is made of! What is Dark Energy? Solving the riddle of Dark Energy is one of the pressing issues in science today.

What Powered the Big Bang? : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 20 What Powered the Big Bang? Gravitational Waves Can Escape from Earliest Moments of the Big Bang Inflation (Big Bang plus 10-34 Seconds) Big Bang plus 300,000 Years gravitational waves Big Bang plus 14 Billion Years light Now

Realizing Science Beyond Einstein : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 21 Realizing Science Beyond Einstein Einstein Observatories providing breakthrough capabilities to address Beyond Einstein science: LISA: Gravitational waves from merging Black Holes Constellation-X: Observe matter falling into Black Holes & address the mysteries of Dark Matter and Dark Energy Einstein Probes address focused science questions: How does Dark Energy evolve? Can we detect the Big Bang? How many Black Holes are there? Education & outreach program, technology investments, and theoretical studies towards the vision Inspire the next generation of scientists and engineers Three inter-linked elements that work together:

Beyond Einstein Program : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 22 Beyond Einstein Program

The Constellation-X Mission : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 23 The Constellation-X Mission Constellation of 4 X-ray telescopes for X-ray imaging and high-resolution spectroscopy (25-100x more sensitive than current high-res X-ray instruments) 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

Laser Interferometer Space Antenna (LISA) : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 24 Laser Interferometer Space Antenna (LISA) Joint NASA-ESA project to design, build and operate the first space-based gravitational wave detector. Three spacecraft separated by 5 million km. Space-time fluctuations induced by gravitational waves are detected by using a laser-based Michelson interferometer to monitor the changes in separation between test masses in the separate spacecraft to very high accuracy. Make precision tests of Einstein’s Theory of Relativity Determine the role of mergers of massive black holes in galaxy evolution Determine the population of ultra-compact binaries in the Galaxy

Einstein Probes : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 25 Einstein Probes Dark Energy Probe Determine the evolution of dark energy with time Identify the nature of dark energy Inflation Probe Study imprints of gravitational waves from inflation on the cosmic microwave background Determine when and how inflation occurred Black Hole Finder Probe To conduct a census of hidden black holes in our Galaxy and beyond Three focused missions, each designed to address a single high priority science question

The 21st Century Beyond Einstein : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 26 How did the Universe begin? Does time have a beginning & an end? The questions are as old as human curiosity. The answers have always seemed beyond the reach of science. . . until now! The 21st Century Beyond Einstein

For more information… : 

12/10/2008 http://beyondeinstein.gsfc.nasa.gov Beyond Einstein 27 For more information… Website: http://beyondeinstein.gsfc.nasa.gov