1. LIGO-G020518-01-W Measuring Ripples in the Geometry of Space Fred Raab LIGO Hanford Observatory

2. LIGO-G020518-01-W LIGO: Portal to Spacetime2 John Wheeler’s Picture of General Relativity Theory

3. LIGO-G020518-01-W LIGO: Portal to Spacetime3 General Relativity: A Picture Worth a Thousand Words

4. LIGO-G020518-01-W LIGO: Portal to Spacetime4 The New Wrinkle on Equivalence Not only the path of matter, but even the path of light is affected by gravity from massive objects Einstein Cross Photo credit: NASA and ESA A massive object shifts apparent position of a star

5. LIGO-G020518-01-W LIGO: Portal to Spacetime5 Gravitational Waves Gravitational waves are ripples in space when it is stirred up by rapid motions of large concentrations of matter or energy Rendering of space stirred by two orbiting black holes:

6. LIGO-G020518-01-W How does LIGO detect spacetime vibrations?

7. LIGO-G020518-01-W LIGO: Portal to Spacetime7 Important Signature of Gravitational Waves Gravitational waves shrink space along one axis perpendicular to the wave direction as they stretch space along another axis perpendicular both to the shrink axis and to the wave direction.

8. LIGO-G020518-01-W LIGO: Portal to Spacetime8 Basic Signature of Gravitational Waves for All Detectors

9. LIGO-G020518-01-W LIGO: Portal to Spacetime9 Laser Beam Splitter End Mirror Screen Viewing Sketch of a Michelson Interferometer

10. LIGO-G020518-01-W LIGO: Portal to Spacetime10 Core Optics Suspension and Control Local sensors/actuators provide damping and control forces Mirror is balanced on 1/100 th inch diameter wire to 1/100 th degree of arc Optics suspended as simple pendulums

11. LIGO-G020518-01-W LIGO: Portal to Spacetime11 How Small is 10 -18 Meter? Wavelength of light, about 1 micron One meter, about 40 inches Human hair, about 100 microns LIGO sensitivity, 10 -18 meter Nuclear diameter, 10 -15 meter Atomic diameter, 10 -10 meter