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Visuals: Unit 3

Animations

Eot-Wash Pendulum Data
Eot-Wash Pendulum Data
The data from the first Eot-Wash Pendulum showed that the inverse square law held true down to a distance of 1/5th of a millimeter, or 200 microns.
Eot-Wash Torsion Balance
Eot-Wash Torsion Balance
The Eot-Wash Group redesigned the classic torsion balance, dramatically increasing its precision and pushing the boundaries of what could be measured.
Theory of Extra Dimensions
Extra Dimensions
One possible scenario offered by theorists to explain the apparent weakness of gravity is that the universe is made up of more than three spatial dimensions.
Gravitational Attraction in Torsion Balance
Gravitational Attraction in Torsion Balance
The gravitational force between the pendulum and the attractor depends on the position of the holes.
When a gravitational wave reaches the interferometer, it will shrink one arm and stretch the other arm causing the laser beams t
LIGO Interferometer and Constructive Interference
When a gravitational wave reaches the interferometer, it will shrink one arm and stretch the other arm causing the laser beams to be slightly out of phase.
An interferometer splits a laser beam and then recombined it. If the waves are perfectly out of phase they cancel each other out
LIGO Interferometer and Destructive Interference
An interferometer splits a laser beam and then recombined it. If the waves are perfectly out of phase they cancel each other out—a phenomenon called "destructive interference."
LIGO Yardstick: This yardstick is among the most accurate in the world.
LIGO Yardstick
This laser yardstick will be used to detect miniscule, fleeting changes in its overall measured length as gravitational waves sweep over it.
Measuring Gravity with Laser Light
Measuring Gravity with Laser Light
To measure how strong gravity is between the two discs, laser light is bounced off the mirrors above the top pendulum disc.

Photographs

man on the moon, cube reflectors,
Apollo Mission Corner Cubes
Apollo mission astronauts deploy corner cube reflectors.
Bar Detector
Bar Detector
Nautilus cryogenic antenna at the Laboratori Nazionali di Frascati, Italy.
LIGO
LIGO Observatory
Aerial view of the LIGO Observatory at Hanford, Washington.
star forming region of the small magellanic cloud
Star-Forming Region
Hubble Space Telescope image of a star-forming region in the Small Magellanic Cloud.
As gas falls into this supermassive black hole, it emits x-rays.
Supermassive Black Hole
As gas falls into this supermassive black hole, it emits x-rays.
Torsion balance
Torsion Pendulum to Measure UFF
Torsion pendulum to test the universality of free fall.
Newton and Einstein portraits
Two Influential Scientists: Newton and Einstein
Portraits of Sir Isaac Newton (left) and Albert Einstein (right).

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Graphics

The apparent equivalence between gravity and acceleration.
Acceleration and Gravity
A person in an accelerating rocket feels the same downward pull as a person on Earth feels from gravity.
Bending of light in an accelerating rocket.
Bending of Light
Bending of light in an accelerating rocket.
Graph of binary pulsar decay
Binary Pulsar Decay
Orbital period of the binary neutron star system PSR 1913+15 measured from 1975 to 2000.
Causal Dynamical Triangulation builds the spacetime in which we live from tiny triangles.
Causal Dynamical Triangulation
Causal Dynamical Triangulation builds the spacetime in which we live from tiny triangles.
The Michelson interferometer now finds application in a 21st century experiment: the search for gravitational waves. The diagram
Classic Michelson Interferometer
The Michelson interferometer now finds application in a 21st century experiment: the search for gravitational waves. The diagram shows the original version of the instrument.
Triangles on curved surfaces
Curved Spacetime
Triangles on curved surfaces.
Comparison of Shielding Forces.
Electrostatic and Gravitational Shielding
Comparison of the shielding of electrostatic and gravitational forces.
graph of experimental limits on inverse square law violations.
Experimental Limits on ISL Violations
Experimental limits on the universality of free fall.
Grace Mission map
GRACE Mission
GRACE mission gravity map of the Earth.
gravity force of two spheres
Gravitational Attraction
Gravitational attraction between two spheres causes a tiny change in their positions.
Distortion of space from a gravitational wave
Gravitational Waves
Distortion of space from a gravitational wave.
Helium atom
Helium Atom
Mass of a helium atom is not equal to the sum of its constituent parts.
LISA satellites
LISA Satellites
Artist's conception of the LISA satellites in space.
loop quantum gravity
Loop Quantum Gravity
Visualization of a stage in the quantum evolution of geometry, according to Loop Quantum Gravity.
Law of universal gravitation force diagram.
Newton's Law of Universal Gravitation
Law of universal gravitation force diagram.
Short distance gravity test
Short-Distance Gravity Test
Torsion pendulum to test the inverse square law of gravity at sub-millimeter distances.
Simulations of structure formation in the universe show the influence of gravity and dark energy
Structure in the Universe
Simulations of structure formation in the universe show the influence of gravity and dark energy.
Tidal Water Level Plot.
Tidal Water Level
Plot of the tidal Water Level (WL) at Port Townsend, Washington.
Schematic of a torsion balance to measure the gravitational constant, G
Torsion Balance to Measure G
Schematic of a torsion balance to measure the gravitational constant, G.
twin paradox graph
Twin Paradox
Time dilation/twin "paradox."
uniform gravitational field
Uniform Gravitational Field
Equality of gravitational and inertial mass.