How Gravitational Waves Stretch Spacetime

Have you ever wondered how invisible events in the deepest parts of the universe can actually push and pull on things here on Earth? Imagine spacetime as a flexible rubber sheet stretched across the cosmos holding every planet and star. Now imagine placing two heavy bowling balls representing black holes onto our rubber sheet and spinning them around each other in a circle. As these massive objects accelerate through space, they create disturbances that ripple outward across the fabric in every direction.

To understand what these waves actually do, watch the grid squares as the ripples wash over them. The passing wave does not push things along its path, but instead alternately stretches and compresses the space it travels through. This sideways stretching and squeezing is called the plus polarization mode. There is also a second way these waves deform space known as the cross polarization mode.

Tilted at a 45° angle. Scientists built giant instruments called laser interpherometers, often referred to as LIGO, which use light bouncing down two long perpendicular tunnels to measure changes in distance. Suppose the wave stretches a distance of 1 meter by a tiny fraction known scientifically as 10 to the power of -21. That means the change in length is so unimaginably small that a distance equal to the distance to the nearest star changes by less than the width of a single atom.

That tiny signal was successfully measured for the first time by human detectors, confirming Einstein's century old prediction. By listening to these ripples, you can now hear the invisible collisions of the universe happening all around us. Generate your own educational videos for free at eduvids. app.

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