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COLOQUIOS DEL DEPARTAMENTO DE
FÍSICA<BR>
FCEyN -
UBA<BR><BR>
Charla, café y
masitas<BR> En
el <STRONG>Aula 9</STRONG>, 1er piso Pabellón
I.<BR>
Ciudad
Universitaria<BR><BR><BR> El
próximo jueves 2 de noviembre a las 14 hs</FONT>
<DIV><FONT face=Arial size=2><FONT face=Arial size=2></FONT></FONT> </DIV>
<DIV><FONT face=Arial size=2><FONT face="Times New Roman"><FONT
size=4><STRONG> </STRONG>
Conical diffraction: </FONT></FONT></FONT></DIV>
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Imaging Hamilton´s diabolical point</FONT><FONT
size=3> </FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial size=2><FONT face="Times New Roman"><FONT
size=3> </FONT></FONT><FONT
face=Arial size=2><FONT face="Times New Roman"><FONT
size=3><STRONG></STRONG></FONT></FONT></FONT></DIV>
<DIV><FONT face=Arial size=2><FONT face="Times New Roman"><FONT
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Michael Berry</FONT></FONT></FONT></DIV>
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Physics Department, Bristol University</SPAN></FONT></FONT></FONT>
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<DIV><FONT face="Times New Roman" size=3>RESUMEN:</FONT></DIV>
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face="Times New Roman"><?xml:namespace prefix = o ns =
"urn:schemas-microsoft-com:office:office" /><O:P><FONT size=3> </FONT>
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style="FONT-SIZE: 16pt; mso-bidi-font-size: 12.0pt"><FONT
face="Times New Roman"><FONT size=3><SPAN
style="FONT-SIZE: 16pt; COLOR: black; FONT-FAMILY: 'Times New Roman'; mso-ansi-language: ES; mso-fareast-font-family: 'Times New Roman'; mso-fareast-language: ES; mso-bidi-language: AR-SA; mso-bidi-font-size: 12.0pt"><FONT
size=3>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt" align=justify>The
transformation of a narrow beam into a hollow cone when incident along the
optic axis </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt" align=justify>of a
biaxial crystal, predicted by Hamilton in 1832, created a sensation when
observed by </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt" align=justify>Lloyd
soon afterwards. It was the prototype of the conical intersections now popular
in quantum </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt"
align=justify>chemistry. But the fine structure of the light cone contains many
subtle features, slowly revealed </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt" align=justify>by
experiment, whose definitive explanation, involving new mathematical
asymptotics, has been </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt"
align=justify>achieved only recently, along with definitive experimental test of
the theory. Radically different </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt"
align=justify>phenomena, being intensively studied now, arise when chirality and
absorption are incorporated </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt" align=justify>in
addition to biaxiality.</P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt"
align=justify> </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt"></FONT><FONT
face=Arial
size=2>-------------------------------------------------------------------------------------------------</FONT></P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt"><FONT face=Arial
size=2></FONT> </P>
<P class=MsoBlockText style="MARGIN: 0cm 22.2pt 0pt 23.25pt"><FONT face=Arial
size=2>Los
esperamos!</FONT></SPAN></FONT></FONT></SPAN></FONT></O:P></FONT></SPAN><SPAN
style="mso-ansi-language: ES"><SPAN lang=ES-MX
style="FONT-SIZE: 11pt; mso-ansi-language: ES-MX"><SPAN lang=ES-MX
style="FONT-SIZE: 16pt; mso-ansi-language: ES-MX; mso-bidi-font-size: 11.0pt"><SPAN
lang=ES-AR
style="mso-ansi-language: ES-AR"></P></DIV></DIV></SPAN></SPAN></SPAN></SPAN></FONT></FONT></FONT></FONT></DIV></BODY></HTML>