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<div align="center"><big> <b><big><br>
</big></b></big></div>
<div align="center"><big><b><big>Welcome to the 2021 Fall talks
of ODTU-Bilkent Algebraic Geometry Seminars</big></b></big><b><br>
</b><b> </b><b> </b></div>
<b> </b>
<div align="center"><i>since 2000</i><br>
<b> </b> </div>
<div align="center"><b> </b><b> </b><b><b>=================================================================</b>
</b><br>
<b> </b><br>
This week the <a
href="http://www.bilkent.edu.tr/%7Esertoz/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>
<br>
<b>=================================================================</b></div>
<div align="center"><br>
<br>
<div align="center"><b><img
src="cid:part1.8eA60Rno.VpxHq0eV@bilkent.edu.tr" alt=""
class=""> </b><font size="-1"><i> </i></font></div>
<div align="center"><font size="-1"><i>Paul Gauguin
(1848-1903)<br>
</i></font></div>
<div align="left"><br>
<b><b><font color="#ff0000">Speaker:<font color="#000000">
Oğuzhan Yürük</font></font></b></b></div>
<div align="left"><b><b><font color="#ff0000">Affiliation: <font
color="#000000">TU-Berlin</font><br>
Title:<font color="#000000"> Nonnegativity of the
polynomials supported on circuits<br>
</font><br>
</font></b></b></div>
</div>
<div align="left"><b><b><font color="#ff0000">Abstract:</font></b></b><font
color="#ff0000"><font color="#000000"> A real multivariate
polynomial is called nonnegative if its evaluation at any
given point in R^n is nonnegative. Checking the
nonnegativity of a real polynomial is a not only a
mathematically challenging task, but also is an effective
tool both for mathematics and for sciences. Often one uses
nonnegativity certificates in order to tackle this
problem, i.e., easily verifiable conditions that imply the
nonnegativity for a large class of polynomials. The
typical nonnegativity certificates usually make use of the
fact that a polynomial is nonnegative if it is a sum of
squares of polynomials (SOS polynomial), however not every
nonnegative polynomial is of this form. In the first part
this talk, we focus on a relatively new nonnegativity
certificate based on the arithmetic and geometric means
(AM-GM) inequality, and we elaborate on the fact that this
class of polynomials neither contains nor is contained in
the class of SOS polynomials. Unlike the SOS certificates,
one is only interested in the exponents that show up in
the support while working with AM-GM certificates. In
particular, this gives us a framework to write sufficient
symbolic conditions for the nonnegativity of a given
sparse polynomial in terms of its coefficients. We utilize
the aforementioned AM-GM framework in the second part of
the talk, and present an application to a particular
problem from the chemical reaction networks theory. <br>
</font></font></div>
<div align="left"><font color="#ff0000"><font color="#000000"><br>
</font></font></div>
<div align="left"><font color="#ff0000"><font color="#000000"><b><font
color="#ff0000">Date:<font color="#000000"> 15 October
2021</font></font></b>, Friday</font></font><br>
</div>
<div align="left"><font color="#ff0000"><font color="#000000"><b>
<font color="#ff0000">Time: </font>15:40</b><br>
<b><font color="#ff0000">Place: </font></b><font
color="#ff0000"><font color="#000000"><b>Zoom<br>
</b></font></font></font></font></div>
<div align="left"><font color="#ff0000"><font color="#000000"><font
color="#ff0000"><font color="#000000"><b><br>
</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"
moz-do-not-send="true">sertoz@bilkent.edu.tr</a>.</b></b></font></font></font></font></p>
</blockquote>
<p><font color="#ff0000"><font color="#000000"><font
color="#ff0000"><font color="#000000"><b> </b></font></font></font></font></p>
<div align="left"><br>
</div>
<div align="left">Please bring your own tea and cookies and
self-serve at the convenience of your own home! 😁<span
class="gmail-moz-smiley-s1"></span></div>
<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<br>
<font color="#ff0000"><font color="#000000"><b><font
color="#ff0000"> </font></b></font></font></div>
<pre class="gmail-moz-signature" cols="72">----------------------------------------------------------------------------
Ali Sinan Sertöz
Bilkent University, Department of Mathematics, 06800 Ankara, Turkey
Office: (90)-(312) - 290 1490
Department: (90)-(312) - 266 4377
Fax: (90)-(312) - 290 1797
e-mail: <a class="gmail-moz-txt-link-abbreviated moz-txt-link-freetext" href="mailto:sertoz@bilkent.edu.tr" moz-do-not-send="true">sertoz@bilkent.edu.tr</a>
Web: <a href="http://sertoz.bilkent.edu.tr" moz-do-not-send="true">sertoz.bilkent.edu.tr</a>
----------------------------------------------------------------------------</pre>
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