Does the Earth produces measurable gravity waves? Does the Earth exhibit measurable gravity waves? Note: I'm not asking about gravitational waves.
Some recent experiments looking at low-frequency (3$\times 10^{-5}$Hz) accelerometer data are showing some features that might be explained by this. The signal that I and others have measured shows a signal at least 10 to 15 dB above the noise floor that appears to change somewhat based on local geology as determined between measurements in Japan, Hawaii, and the continental US.
Any insight into crustal gravity waves with a period of roughly 9 hours, or other phenomena that might result in reproducible signals like this in accelerometers is appreciated.
Any suggestions for further analysis that might differentiate among different possible explanations is also welcome!
Edit: This answer refers to the first version of this question which asked about &quot;gravitational waves&quot;.
Typically, the term &quot;gravitational wave&quot; is reserved for distortions (&quot;strain&quot;) in spacetime, in accordance with General Relativity. Gravitational waves are a property of spacetime and can thus propagate in empty space. In contrast, what you measure here are simply seismic waves, such as pressure waves propagating through Earth and your setup. In fact, seismic waves are the limiting noise that prevents gravitational wave detectors such as aLIGO to measure at lower frequencies, see e.g. this paper for a discussion and plots.