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WHAT POWERED THE BIG BANG?. WHAT HAPPENS AT THE EDGE OF A BLACK HOLE?. WHAT IS DARK ENERGY?. National Aeronautics and Space Administration. Presented by Dr. James Lochner (USRA & NASA/GSFC). Beyond Einstein. Einstein’s Predictions Expanding Universe Black Holes Dark Energy
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WHAT POWERED THE BIG BANG? WHAT HAPPENSAT THE EDGEOF A BLACK HOLE? WHAT ISDARK ENERGY? National Aeronautics andSpace Administration Presented by Dr. James Lochner (USRA & NASA/GSFC)
Beyond Einstein • Einstein’s Predictions • Expanding Universe • Black Holes • Dark Energy • Evidence for those predictions • Lingering Questions … • What Powered the Big Bang? • What Happens at the Edge of a Black Hole? • What is Dark Energy? • … And How We’ll Answer them • LISA • Constellation-X • Implications for Your Students
Einstein & Our Universe 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. • Light rays can be bent passing near a massive body. Einstein’s theories also made three startling predictions: • The expansion of the Universe (from a big bang) • Black Holes • Cosmological Constant (acting against pull of gravity) These predictions have been confirmed by observations.
Evidence for the Expanding Universe • We know about Expanding Universe & Big Bang from: • Hubble’s discovery of red-shifted galaxies. • Penzias & Wilson discovery of 3 K background. • Abundances of the light elements. • 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.
Evidence for Black Holes • Black holes in 3 flavors • Stellar (5 - 15 solar masses) • Evident in X-ray Binary Systems • Massive (Million solar masses) • In center 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. • We see effects of strong gravity on nearby matter. • First evidence for frame dragging and black hole rotation.
Evidence for Dark Energy • 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.
1. Create a White Dwarf A dying star becomes a white dwarf.
2. Dump more mass onto it The white dwarf strips gas from its stellar companion….
3. Until it explodes ….and uses it to become a hydrogen bomb. Bang!
4. Observe it in a distant galaxy The explosion is as bright as an entire galaxy of stars…. …..and can be seen in galaxies across the universe.
Redshift Distance via SN Ia Evidence for Dark Energy SN Ia are more distant than expected. Spacetime has expanded more than expected.
Dark Energy and the Universe Flatness of Universe and amount of known matter (and dark matter) means dark energy makes up 70% of the Universe We do not know what 95% of the universe is made of!
Completing Einstein’s Legacy Einstein’s legacy is incomplete, his theory fails to explain the underlying physics of the very phenomena his work predicted • BIG BANG • What powered the Big Bang? • BLACK HOLES • What happens at the edge of a Black Hole? • DARK ENERGY • What is the mysterious Dark Energy pulling the Universe apart?
What Powered the Big Bang? 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 light Now gravitational waves Big Bang plus 14 Billion Years
What Powered the Big Bang? • Gravitational waves coming from • Inflation period and from “phase transitions” • may be detected directly. • Free quarks becoming bound into protons, neutrons, etc • Decoupling of the Electroweak and Strong forces • Wavelength of the Gravitational Waves gives size of Universe at that time.
Sources of Gravitational Waves • Black holes orbiting each other generate gravitational waves. • Merging black holes also generate gravitational waves.
Laser Interferometer Space Antenna (LISA) Joint ESA-NASA project LISA uses a laser based Michelson interferometer to monitor the separation between proof masses in separate spacecraft. • Three spacecraft separated by 5 million km. • Each spacecraft includes two freely falling test masses. • Distance changes measured with precision of 4 ppm RMS over 100 seconds.
What Happens at the Edge of a Black Hole? Black holes are ubiquitous in the Universe Close to a black hole event horizon, extreme distortions of space & time predicted by Einstein can be observed Chandra Deep Image
What Happens at the Edge of a Black Hole? • Japan-US ASCA satellite studied iron gas orbiting near the event horizon of a black hole. • Iron line emission exhibits a distortion due to motion of gas and strong gravitational effects near the black hole. • Line profile provides a probe of regions near black hole.
Measuring Black Holes via Spectroscopy • Better determination of black hole parameters by studying individual blobs falling into event horizon. • Measure effects of black hole spin on nearby space-time. • Study intermediate size black holes. • Growth of supermassive black holes early in the universe.
Constellation-X A fleet of 4 X-ray Telescopes to perform high resolution spectroscopy on faint x-ray sources • Each telescope 10 meter focal length. • 4 telescopes increase the light collection area. • Launched on two Delta rockets. • Placed at L2 point (4x distance to moon) • 4 - 10 year lifetime.
Constellation-X: Achieving High Resolution Spectroscopy X-ray Microcalorimeter Spectrometer: Measure the heat from an x-ray to determine the x-ray’s energy. Resolution of 4 ev for a 6 kev x-ray energy. (25x-100x better than current sensitivity.)
What is the Dark Energy? Einstein introduced the Cosmological Constant to explain what was then thought to be a static Universe, “my biggest mistake . . . ” • Empty space has energy. It’s gravitational effect pushes the universe apart. • Need a form of energy that is elastic: • Vacuum energy (= Cosmol. Const.) • But it’s effect may be too large • Quintessence (particle field) • Astronomical Tools: Surveillance & Interrogation • Measure expansion via fluctuations in CMB. • Measure expansion via more SN and clusters of galaxies.
Constellation-X and Dark Energy • Dark Energy with Galaxy Clusters • Compare Distance with redshift to measure history of expansion of the universe. • Examine the growth of structure in the universe.
Realizing Science Beyond Einstein Three inter-linked components that work together: • Einstein Great Observatoriesproviding breakthrough increases in capabilities to address all Beyond Einstein science: • LISA: Gravitational waves from merging black holes and the early Universe. • Constellation-X: Spectroscopy close to the event horizon of black holes and place constraints on dark side of the Universe. • Einstein Probesto address focused science objectives: • Determine the amount and nature of the Dark Energy. • Search for the signature of inflation in the microwave background via gravitational waves. • Take a census of Black Holes of all sizes in the Universe. • A technology program, theoretical studies and an education program to inspire future generations of scientists and engineers towards the vision: • Directly detect the gravitational waves emitted during the Big Bang. • Image and resolve the event horizon of a Black Hole.
Black Hole Imager 0.1 micro arc sec resolution 4-8 m arc sec Image a Black Hole! Hubble, Chandra, and other observatories are showing black holes are common place in the Universe. Black holes provide a unique laboratory to test Einstein’s theory of gravity. HST Image M87 0.1 arc sec resolution A future black hole imager with a resolution one million times Hubble will observe the effects Einstein predicted. X-ray emission from close to the event horizon provides a powerful probe.
Observe the Big Bang • Detect the gravitational waves from the earliest moments after the Big Bang. • Provides a direct view of the formation of space and time. • Big Bang Observer will also detect mergers of neutron stars and black holes, giving the rate of expansion of the universe through time.
The Story of “Beyond Einstein” • Science is an endless frontier • Einstein changed our way of thinking about the universe, but we are going beyond that. • Science is a search for answers • Nature of science inquiry • Science as a process and as a human endeavor. • When we do not know the answers, we work on phrasing the questions. • We push the envelope of what we know. • We push the envelope of our technology.
The 21st Century How did the Universe begin? Does time have beginning & an end? Does space have edges? The questions are as old as human curiosity. But the answers have always seemed beyond the reach of science. . . until now!
Einstein Probes Three focused missions, each designed to address a single high priority science question: • Dark Energy Probe • Determine amount of dark energy, and whether it changes. • Ex. Search for large numbers of Type Ia supernovae. • Inflation Probe • Map polarization of Microwave Background to search for signature of gravitational waves from the Big Bang. • Black Hole Finder Probe • Take census of black holes in the universe • Ex. Use wide-field X-ray telescope