Ian Taylor
Jul24-05, 04:42 PM
<jabberwocky><div class="vbmenu_control"><a href="jabberwocky:;" onClick="newWindow=window.open('','usenetCode','toolbar=no, location=no,scrollbars=yes,resizable=yes,status=no ,width=650,height=400'); newWindow.document.write('<HTML><HEAD><TITLE>Usenet ASCII</TITLE></HEAD><BODY topmargin=0 leftmargin=0 BGCOLOR=#F1F1F1><table border=0 width=625><td bgcolor=midnightblue><font color=#F1F1F1>This Usenet message\'s original ASCII form: </font></td></tr><tr><td width=449><br><br><font face=courier><UL><PRE>As I understand it, black holes have a temperature ascribed to them\nsince they can emit radiation (by virtue of the fact one particle of a\nvirtual pair spontaneously arising from the vacuum can "drop" into the\nhole whilst the other may escape). I can also see that for large,\nnon-rotating black holes, this process is probably sufficiently common\nfor the emitted radiation to be isotropic.\n\nHowever, for microscopic black holes, it seems much more likely to me\nthat the emitted particles are not distributed isotropically, For\nexample if a photon were to be emitted, it would have a certain\ndirection. This would imply a certain momentum being carried away which\npresumably has to be balanced by the black hole accelerating to a speed\nwhich gives the opposite momentum to the photon. During this\nacceleration, the black hole would be bathed in Unruh radiation. Is it\npossible then, instead of the microscopic black hole temperature\nincreasing without limit, for some kind of equilibrium to be achieved.\n(Or have I completely misunderstood what is going on here ?)\n\nIan Taylor\nhttp://www.iantaylor.org.uk/\n\n</UL></PRE></font></td></tr></table></BODY><HTML>');"> <IMG SRC=/images/buttons/ip.gif BORDER=0 ALIGN=CENTER ALT="View this Usenet post in original ASCII form"> View this Usenet post in original ASCII form </a></div><P></jabberwocky>As I understand it, black holes have a temperature ascribed to them
since they can emit radiation (by virtue of the fact one particle of a
virtual pair spontaneously arising from the vacuum can "drop" into the
hole whilst the other may escape). I can also see that for large,
non-rotating black holes, this process is probably sufficiently common
for the emitted radiation to be isotropic.
However, for microscopic black holes, it seems much more likely to me
that the emitted particles are not distributed isotropically, For
example if a photon were to be emitted, it would have a certain
direction. This would imply a certain momentum being carried away which
presumably has to be balanced by the black hole accelerating to a speed
which gives the opposite momentum to the photon. During this
acceleration, the black hole would be bathed in Unruh radiation. Is it
possible then, instead of the microscopic black hole temperature
increasing without limit, for some kind of equilibrium to be achieved.
(Or have I completely misunderstood what is going on here ?)
Ian Taylor
http://www.iantaylor.org.uk/
since they can emit radiation (by virtue of the fact one particle of a
virtual pair spontaneously arising from the vacuum can "drop" into the
hole whilst the other may escape). I can also see that for large,
non-rotating black holes, this process is probably sufficiently common
for the emitted radiation to be isotropic.
However, for microscopic black holes, it seems much more likely to me
that the emitted particles are not distributed isotropically, For
example if a photon were to be emitted, it would have a certain
direction. This would imply a certain momentum being carried away which
presumably has to be balanced by the black hole accelerating to a speed
which gives the opposite momentum to the photon. During this
acceleration, the black hole would be bathed in Unruh radiation. Is it
possible then, instead of the microscopic black hole temperature
increasing without limit, for some kind of equilibrium to be achieved.
(Or have I completely misunderstood what is going on here ?)
Ian Taylor
http://www.iantaylor.org.uk/