On Tue, Oct 29, 2024 at 11:31 AM Alan Grayson <[email protected]> wrote:
*>> 2000 RPMs is a trivially slow **angular frequency, and as I said the > radiated power is proportional to the fourth power of the **angular > frequency; so one revolution per 24 hours would be SUPER **trivially > slow.* > > > *>I see. So the spinning baseball is sort-of a model for the spinning > Earth. Without doing too much work, what's your best estimate for the time > the Earth completely evaporates due to energy lost due to rotation? AG * > *The Earth won't evaporate it's just that the rotation around its axis will slow down, it would certainly take far longer than the age of the universe to be detectable but it's difficult to calculate exactly how long because it depends on slight irregularities, if the Earth was a perfect homogeneous sphere it wouldn't radiate at all from rotating around its axis, but perfect spheres don't exist, although it would still radiate due to its rotation around the sun.* *The Earth also generates gravitational waves due to its orbit around the sun, somebody did calculate that but it turns out to only amount to about 200 watts of energy, so it would take about a billion trillion years before Earth's orbit decayed noticeably from that. However this effect can be important if instead of talking about the Earth we're talking about two Black Holes or Neutron Stars that are several times the mass of the sun and are moving close to the speed of light in an orbit only about a thousand miles across, then a gravitational detector such as LIGO can detect those waves even if they're coming from the other side of the observable universe. In fact, in the last fifth of a second before two rotating Black Holes collide they can radiate about 100 times more energy in the form of gravitational waves than all the stars in the observable universe radiate in the form of light combined. * * John K Clark See what's on my new list at Extropolis <https://groups.google.com/g/extropolis>* /qz -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion visit https://groups.google.com/d/msgid/everything-list/CAJPayv2RovsRy4NmqWtRdmDvWppksSmw76zp3d1fkW%2BA8FF44Q%40mail.gmail.com.
