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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I had an idea upon which John or the other astronomy hipsters might comment.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I noticed the masses of the merging black holes seemed to be remarkably even with each other, within a factor of 2:<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>First event, masses of 29 and 35<o:p></o:p></p><p class=MsoNormal>Second event, masses of 8 and 14<o:p></o:p></p><p class=MsoNormal>Third event, masses of 19 and 31<o:p></o:p></p><p class=MsoNormal>Fourth event, masses of 25 and 30<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Today a notion occurred to me: there is a reason why this might not be just a crazy coincidence or a characteristic of the LIGO instrument to detect only a certain class of mergers.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Consider any two black holes locked into mutual orbit. Always the smaller hole goes into a bigger orbit, so it travels faster and traverses more space. The pair attracts stuff, so gas and perhaps stars are devoured, but always the smaller black hole grows faster because of covering more ground: anything that falls inward toward the pair has a higher chance of being gobbled by the smaller black hole.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>This might explain why the four observations seen so far are mergers between black holes of almost the same mass.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>spike<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>