Gravitational waves travel through time and space by propagating as ripples in the fabric of spacetime itself. According to Albert Einstein's theory of general relativity, massive objects deform the fabric of spacetime, creating a gravitational field. When these massive objects undergo certain types of acceleration or motion, such as orbiting each other or colliding, they emit gravitational waves.
Gravitational waves are disturbances in the curvature of spacetime that propagate outward from their source at the speed of light. As they travel, they cause spacetime to stretch and compress in a wave-like manner. This stretching and compressing of spacetime is what we perceive as the gravitational wave itself.
Unlike electromagnetic waves, which require a medium like air or a material to propagate through, gravitational waves can travel through the vacuum of space. They are not restricted by matter or electromagnetic fields and can traverse vast cosmic distances.
As gravitational waves pass through an observer, they cause local spacetime to expand and contract, resulting in a tiny oscillation or displacement of objects in their path. However, the effect of gravitational waves on matter is incredibly small, making their detection a technological challenge.
Gravitational wave detectors, such as the Laser Interferometer Gravitational-Wave Observatory (LIGO) and the Virgo interferometer, use precise measurements of laser light to detect the minute changes in distance caused by passing gravitational waves.
In summary, gravitational waves travel through time and space by deforming and propagating as ripples in the fabric of spacetime itself, causing local oscillations in matter as they pass through.