It’s called the Schumann Resonance and yes it’s a real thing. Considered to be 7.83 Hz but it can fluctuate based on variables such as solar flares.
https://image.gsfc.nasa.gov/poetry/ask/q768.html
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There is a lot of speculation as to what this could mean for humans and life on the planet. Some interesting thoughts in this article but again, speculation, there isn’t a lot of science yet on most of this. I do agree with this part, which is based in brain science. Our technology world is accelerating stress and disease. Time to hug a tree. 
It would seem then that our nervous system can be influenced by the earth’s electromagnetic field. Maybe that’s why being in nature has always been so restorative and healing. Disconnecting from a typical city setting by reducing our exposure to crowds, traffic, work, and routine life—and instead getting out in natural surroundings—can slow our brain waves down from the aggressive, vigilant, anxious, and impatient states that are seen in higher ranges of beta brain waves to more restorative alpha waves.
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What I have a problem with is when some people/companies try to capitalize on people’s ignorance with exaggerated claims in order to make a buck:
https://quwave.com/Resonances.html
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In the above article he suggests that the Schumann Resonance is the vibration that the ancient rishis of India called OM or AUM; the vibration of the cosmos! Close, maybe, but just our planet most likely. I think it’s possible that in deep meditation they could sense this vibration. Obviously, we can’t really hear it as it’s too low for our ears to detect, though there may be overtones of it that could possibly be audible at times.
Among other things. Yeah been away awhile. Decided to do a quick ‘flyby’ mission. I may get back into synchronous orbit soon. 
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