Gravitational waves

Definition

Gravitational waves are ripples in spacetime caused by accelerating masses, predicted by Einstein's General Theory of Relativity. They propagate at the speed of light and can be detected by their effect on the distance between objects.

5 Must Know Facts For Your Next Test

1. Gravitational waves were first directly detected by LIGO in 2015 from a collision of two black holes.
2. They carry energy away from their source in the form of gravitational radiation.
3. The amplitude and frequency of gravitational waves can provide information about their sources, such as merging black holes or neutron stars.
4. Gravitational waves have two polarizations: plus (+) and cross (×).
5. They are extremely weak, requiring highly sensitive instruments like interferometers to detect them.

Review Questions

• What event led to the first direct detection of gravitational waves?
• How do gravitational waves interact with matter as they pass through it?
• What are the two polarizations of gravitational waves?

Related terms

General Relativity: A theory of gravitation developed by Albert Einstein which describes gravity as a property of the curvature of spacetime caused by mass and energy.

Interferometer: A device that uses the interference of light waves to measure small distances or changes in distance with high precision, crucial for detecting gravitational waves.

Black Hole Merger: An astronomical event where two black holes spiral inward and merge, often producing detectable gravitational waves.