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<div align="center"><big><b><big>Welcome to the 2025
Spring talks of ODTU-Bilkent Algebraic Geometry
Seminars</big></b></big><b><br>
</b></div>
<div align="center"><i>since 2000</i><br>
</div>
<div align="center"><b><b>=================================================================</b></b><br>
<br>
This week the <a
href="http://www.bilkent.edu.tr/~sertoz/agseminar.htm"
target="_blank" moz-do-not-send="true">ODTU-Bilkent
Algebraic Geometry Seminar</a> is <b>online</b><br>
<br>
<i><font color="#ff00ff">This talk will begin at <u><b>15:40</b></u><u> (GMT+3)</u></font></i><br>
<a
href="https://www.timeanddate.com/worldclock/fixedtime.html?msg=ODT%C3%9C-Bilkent+Algebraic+Geometry+Seminar&iso=20250425T1540&p1=19&ah=1"
target="_blank" moz-do-not-send="true">Please check
your time difference between Ankara and your city here</a><br>
<b>=================================================================<br>
<br>
</b></div>
<div align="center">
<div align="center"><img
src="cid:part1.0NuMvmsJ.JAGyfXPe@bilkent.edu.tr"
alt="" width="724" height="404" class=""></div>
</div>
<div align="center"><br>
</div>
<div align="center"><i>Vincent van Gogh (1853-1890)<br>
On the morning of 29 July 1890 Tuesday he was working
on this painting. Later that day, in a field near
Auvers, Vincent shot himself in the chest with a
revolver. He died two days later, with his brother
Theo at his bedside. <br>
This painting is now on exhibition in the Van Gogh
Museum in Amsterdam.</i></div>
<div align="center"><i><br>
</i></div>
<div align="center"><i><br>
</i>
<div align="left"><b><b><font color="#ff0000">Speaker:
<font color="#000000"><a
href="https://avesis.metu.edu.tr/hsuluyer"
moz-do-not-send="true">Hasan Suluyer</a></font></font></b><b><font
color="#ff0000"><font color="#000000"> <br>
</font></font></b></b><b><b><font
color="#ff0000">Affiliation: </font><i>ODTÜ</i></b></b></div>
<div align="left"><b><b><i><br>
</i></b></b></div>
<div align="left"><b><b><font color="#ff0000"> Title: <font
color="#000000">Pencils of Conic-Line Curves<br>
</font></font></b><b><font color="#ff0000"><font
color="#000000"><br>
</font></font></b></b></div>
</div>
<div align="left"><b><b><font color="#ff0000">Abstract: </font></b></b>A
pencil is a line in the projective space of complex
homogeneous polynomials of some degree d > 2. The
number m of curves whose irreducible components are only
lines in some pencils of degree d curves plays an
important role for the existence of special line
arrangements, which are called (m,d)-nets. It was proved
that the number m, independent of d, cannot exceed 4 for
an (m,d)-net. When the degree of each irreducible
component of a curve is at most 2, this curve is called
a conic-line curve and it is a union of lines or
irreducible conics in the complex projective plane. Our
main goal is to find an upper bound on the number m of
such curves in pencils in CP^2 with the number of
concurrent lines in these pencils.<br>
<br>
In this talk, we study the restrictions on the number m
of conic-line curves in special pencils. The most
general result we obtain is the relation between upper
bounds on m and the number of concurrent lines in these
pencils. We construct a one-parameter family of pencils
such that each pencil in the family contains exactly 4
conic-line curves.<b><b><font color="#ff0000"><br>
<br>
</font></b></b></div>
<div align="left"><br>
</div>
<div align="left"><font color="#ff0000"><font
color="#000000"><b><font color="#ff0000">Date:<font
color="#000000"> 25 April 2025</font></font></b>,
<b>Friday</b></font></font><br>
</div>
<div align="left"><font color="#ff0000"><font
color="#000000"><b><font color="#ff0000">Time: </font>15:40 <i>(GMT+3)</i></b><br>
<b><font color="#ff0000">Place: </font></b><font
color="#ff0000"><font color="#000000"><b>Zoom</b></font></font></font></font></div>
<blockquote>
<p><font color="#ff0000"><font color="#000000"><font
color="#ff0000"><font color="#000000"><b><b
style="color:rgb(51,51,51);font-family:arial,verdana,sans-serif;font-size:14px">One
day before the seminar, an announcement
with the Zoom meeting link will be sent to
those who registered with Sertöz.<br>
</b></b></font></font></font></font></p>
<p><font color="#ff0000"><font color="#000000"><font
color="#ff0000"><font color="#000000"><b><b
style="color:rgb(51,51,51);font-family:arial,verdana,sans-serif;font-size:14px">If
you have registered before for one of the
previous talks, there is no need to
register again; you will automatically
receive a link for this talk too.<br>
</b></b></font></font></font></font></p>
<p><font color="#ff0000"><font color="#000000"><font
color="#ff0000"><font color="#000000"><b><b
style="color:rgb(51,51,51);font-family:arial,verdana,sans-serif;font-size:14px">If
you have not registered before, please
contact him at <a
href="mailto:sertoz@bilkent.edu.tr?subject=Zoom%20Seminar%20Address%20Request"
target="_blank" moz-do-not-send="true">sertoz@bilkent.edu.tr</a>.</b></b></font></font></font></font></p>
</blockquote>
<div align="left"><br>
</div>
<div align="left">You are most cordially invited to
attend.</div>
<div align="left"><br>
</div>
<div align="left">Ali Sinan Sertöz</div>
<div align="left"><br>
</div>
<div align="center">
<div align="center"><b><font color="#0080c0"><i><b><font
color="#0080c0"><i>This seminar series is
organized by a joint team from ODTÜ and
Bilkent<br>
<br>
Alexander Degtyarev (Bilkent)<br>
Ali Sinan Sertöz (Bilkent) contact person<br>
Ali Ulaş Özgür Kişisel (ODTÜ)<br>
Yıldıray Ozan (ODTÜ)<br>
</i></font></b></i></font></b></div>
</div>
<br>
<hr>
<pre cols="72">----------------------------------------------------------------------------
Ali Sinan Sertöz
Bilkent University, Department of Mathematics, 06800 Ankara, Türkiye
Office: (90)-(312) - 290 1490
Department: (90)-(312) - 266 4377
Fax: (90)-(312) - 290 1797
e-mail: <a href="mailto:sertoz@bilkent.edu.tr" target="_blank"
class="gmail-moz-txt-link-freetext moz-txt-link-freetext"
moz-do-not-send="true">sertoz@bilkent.edu.tr</a>
Web: <a href="http://sertoz.bilkent.edu.tr" target="_blank"
moz-do-not-send="true">sertoz.bilkent.edu.tr</a>
----------------------------------------------------------------------------</pre>
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