These are a few of my favorite things…

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These are a few of my favorite things. Black Holes and stretched space Eclipse Cruise 2009. What is a black hole?. A massive spacetime curvature singularity, Surrounded by an event horizon. (a point or ring of infinite density and tidal acceleration) - PowerPoint PPT Presentation

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  • These are a few of my favorite thingsBlack Holes and stretched spaceEclipse Cruise 2009

  • What is a black hole?A massive spacetime curvature singularity,

    Surrounded by an event horizon(a point or ring of infinite density and tidal acceleration)

    (a spacetime boundary between causally disconnected regions of the universe)

  • i was considering how within night's loose sack a star's nibbling in-fin -i- tes- i -mal- ly devoursdarkness the hungry star which will e . -ven tu- al -ly jiggle the bait of dawn and be jerkedintoeternity. when over my head a shooting star Burs(t into a stale shriek like an alarm-clock)

    -- e.e. cummings

    But what is a black hole REALLY?

  • What happens at the event horizon?Be careful where you cross (Euna Lee and Laura Ling, Korea, AP photo)

  • Can matter escape from a BH?Quantum tunneling produces a Particle-Antiparticle pair from the vacuum!

    http://superstringtheory.com/blackh/blackh3.htmlOnly by dissolving into Hawking radiation!

  • Black holes in NatureThe afterlife of giant starsBlack hole masses 3-15 solar masses

    Giant sinkholes in galaxy centersBlack hole masses million to billion solar masses

  • How we find black holes (and neutron stars): X-rays!RossiX-Ray TimingExplorersatellite,launched 1995

  • How do black holes emit X-rays?

    Rotating gas disk with frictional heating

    Artistic conception movie 1

    Artistic conception movie 2

  • How can we prove these are the BH of Einsteins theory?

    Measure the gravitational waves emitted as two black holes merge.Artistic conception 3

  • Prediction of gravitational waves from black hole merger

    Centrella et al, 2008

  • How to describe gravitational wavesOscillating tides Stretching of space

  • What causes the tides?Why are there two high tides daily?

  • A good try, but wrongEarths movement causes the oceans to slosh like water in a bathtub

    Galileo Galilei, 1622

  • Waving SpaceSimulated drum headDan Russell, Kettering U.Cross-section of space fabricoutside a pair of orbiting black holes

  • How to measure this stretching?

  • Replace rings of particles by 4 swinging mirrorsLaser InterferometerWeiss and Drever, 1970s

  • Global network of detectorsLIGOLIGOLISAVIRGOTAMAGEOAIGO

  • LIGO: Laser Interferometer Gravitational-wave ObservatoryLAWA4 km4 km

  • Why so complicated?

    Must measure changes in mirror positions to within 1/1000 diameter of a proton!

    LIGO has succeeded in reaching this goal and now has to observe patiently for gravitational waves.

    When will they discover gravitational waves?

    EB prediction: 2014 or sooner

  • Ultimate successNew Instruments, New Field, the Unexpected

  • Additional Credits and InformationCredits:Rossi X-Ray Timing Explorer figure courtesy NASA/Goddard Space Flight CenterLIGO and other gravitational wave images courtesy Nergis Mavalvala

    Books:The Fabric of the Cosmos, Brian GreeneThe Elegant Universe, Brian GreeneBlack Holes and Time Warps: Einsteins Outrageous Legacy, Kip S. Thorne (more advanced)

  • What causes the tides?Why are there two high tides daily?

  • Gravity weakens with distance

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