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wolram
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I have been reading up on GR and for the life of me i can not understand how GWs travel through or distort space time, do they distort ST or do they travel with space time?
wolram said:do they distort ST or do they travel with space time?
Why should they?wolram said:Thank Syan, peter, i can now imagine how GWs travel, but why do they not just fall into the nearest gravity well, the nearest star?
wolram said:why do they not just fall into the nearest gravity well, the nearest star?
wolram said:As far as i under stand it gravity is a property of space time, so gravity waves( being a table cloth would be dragged down a hole in the table)
Chronos said:It is still an open question if gravity has gravity. The stress energy tensor is unclear on that point. I would say ... I have no idea.
Chronos said:It is still an open question if gravity has gravity. The stress energy tensor is unclear on that point. I would say ...
martinbn said:what is the definition of gravitational waves?
PeterDonis said:The usual definition uses linearized GR, so that the metric is written as ##g_{ab} = \eta_{ab} + h_{ab}##, and then writes the vacuum EFE in terms of this metric, throwing away terms quadratic or higher in ##h_{ab}##, and shows that ##h_{ab}## satisfies a wave equation.
martinbn said:Are you saying that the definition is: if a space-time (vacuum) have a metric that (locally) can be written in the way above and the ##h_{ab}## satisfies a wave equation, then we say that there are gravitational waves in the space-time?
martinbn said:It seems that your phrasing says that this holds for every spacetime, does that mean that it includes the trivial solution i.e. no waves.
Gravitational radiation, also known as gravitational waves, is a form of energy that is emitted by accelerating masses. It is a prediction of Einstein's theory of general relativity, and it is thought to be generated by massive objects such as black holes and neutron stars.
Gravitational radiation causes ripples in the fabric of space-time, similar to how a stone creates ripples in a pond when it is thrown in. These ripples, or waves, travel through space at the speed of light, stretching and squeezing space as they pass through.
Scientists use specialized instruments called interferometers, such as the Laser Interferometer Gravitational-Wave Observatory (LIGO), to detect gravitational waves. These instruments measure tiny changes in the distance between objects caused by the passing of a gravitational wave.
Studying gravitational radiation can give us insight into some of the most extreme and mysterious phenomena in the universe, such as black holes and the early moments of the Big Bang. It can also help us better understand the nature of space-time and the fundamental laws of physics.
While the study of gravitational radiation is primarily driven by scientific curiosity, there are potential practical applications. For example, gravitational wave detectors could be used in the future to improve our ability to accurately measure time and distance, as well as to monitor for potential cosmic events, such as collisions between neutron stars.