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Message: <blockquote data-quote="freyar" data-source="post: 6703506" data-attributes="member: 40227">Umbran gave a nice answer already, but as I thought of some things I wanted to say before I saw it, I'll go ahead and add them. <img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f609.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=";)" title="Wink    ;)"  data-smilie="2"data-shortname=";)" />There are really two ways to look at your question(s).  We can think about things in terms of classical "old-fashioned" physics, as if we'd never heard of quantum physics.  What is gravity like?  A good analogy is electricity and magnetism.  You can have static electric and magnetic fields.  If you have ever sprinkled iron filings around a magnet and watched them line up with the field, that's an example of a static magnetic field.  If you've ever seen someone hold on to a van de Graaf generator, their hair stands on end because of a static electric field.  Those fields are like the basically static gravitational field that holds us to earth or hold the earth in orbit around the sun (or, in relativistic terms, the static but curved spacetime).  On the other hand, electromagnetic waves are also familiar --- good classical examples include radio waves, which are created by moving charges.  Similarly, moving masses create gravity waves, which, yes, mean ripples in spacetime.As Umbran says, in quantum physics, everything is a wave and a particle, simultaneously.  When we think of a photon as a "particle" of light, we really mean it is a very tiny wave that moves at the speed of light.  Those radio waves I mentioned before are really conglomerations of lots and lots of individual photons.  Similarly, a gravity wave would be a conglomeration of lots and lots of gravitons particle/waves (we do have enough understanding of quantum gravity to say that --- they are a common feature of all quantum gravity theories I know of).  Those static fields, like the gravitational field of the earth or a star, are created by what we call "virtual particles."  These are really more little waves, but they're waves that don't look like waves moving at light speed.  They're more like localized ripples.  So the gravity of the earth that we feel is due to lots and lots of little graviton ripples.One other neat thing about gravity waves: like I said before, we're hoping to observe them from the collision and merger of black holes within the next few years.  The fun thing about these gravity waves is that their frequency is expected to be in the same range humans can hear.  So rather than having to plot things about the waves, you can just run the signal from the detector to a speaker and listen to the gravity waves (well, you'd want to take the experimental noise out first).  Black hole mergers should sound like a "chirp" that starts out a low pitch and goes to a high pitch over the course of a few seconds or less.  I've heard output from a number of simulations. <a href="http://www.einstein-online.info/spotlights/chirping_neutron_stars" target="_blank">This site</a> has some audio for you.  The LIGO experiment site also has some, but I'm having trouble getting that to play.</blockquote>

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