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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> extropy-chat [mailto:extropy-chat-bounces@lists.extropy.org] <b>On Behalf Of </b>Tomaz Kristan<br><b>Sent:</b> Saturday, February 13, 2016 5:35 AM<br><b>To:</b> ExI chat list <extropy-chat@lists.extropy.org><br><b>Subject:</b> Re: [ExI] Gravitational Waves Detected By LIGO!<o:p></o:p></span></p><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>Anders,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><p class=MsoNormal><span style='color:#1F497D'>>…</span>How many super-massive black holes like our own Sagittarius A we have inside the 10^9 ly radius sphere around us? From one hundred million to one billion, there about. Each having mass of about 10 million Suns or 1 million small black holes.<o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#1F497D'>>…</span>How often do small black holes rain onto those big ones? I don't know, but at least 10^14 of them have already fallen, apparently. Otherwise we would not have so many so big supermassives. That is at least 10000 per year for the entire history after the Big Bang.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#1F497D'>>…</span>10000 per year, but LIGO does not hear that noise? But caught a much smaller collision?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='color:#1F497D'>>…</span>I find it difficult to believe this<span style='color:#1F497D'>… Tomaz</span><o:p></o:p></p><div><p class=MsoNormal><span style='color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Next time a black hole does drop into our own Sag A, we will detect it, assuming the detector is still around. That black hole has already cleaned up the area around it, so having something new fall in requires just exactly the right encounter between two stars farther out. There is no reason to think this happens very often.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>We can calculate and estimate it however, or better yet, create a simulation. We can use that trick I developed for GIMPS to estimate the time between the next similar event. I am taking good care of my health, hoping to live long enough to see the next one.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>spike<o:p></o:p></span></p></div></div></div></div></body></html>