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<font style="font-family:Arial,Helvetica,sans-serif" size="3" color="black"><span dir="ltr" style="font-size:12pt; background-color:white">Dear all,<br>
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On Tuesday 15 November <span style="white-space:nowrap">Turker Biyikoglu </span>will give a talk in the Bilkent Algebra seminar.<br>
The title of his talk is<br>
"Castelnuovo-Mumford Regularity of Graphs<span style="white-space:nowrap"><font size="2"><span style="font-size:10pt"></span></font></span>".<br>
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Abstract:<br>
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<font style="font-family:Arial,Helvetica,sans-serif; font-size:12pt" size="3" color="black"><span dir="ltr" style="background-color:white">Castelnuovo-Mumford Regularity (simply regularity) measures the complexity of an object (e.g. ideal, module or sheaf)
in algebraic geometry, commutative algebra and discrete geometry. <br>
In general, very little is known even in the case of square-free monomial ideals. By Stanley-Reisner theory, we can associate a simplicial complex to every square-free ideal, and such a simplicial complex can be regarded as an independence of a hypergraph.
Regularity of a simplicial complex can be reformulated by the well-known Hochester's formula.
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If the generating monomials of a square-free ideal are quadratic, then the corresponding simplicial complex is the independence complex of a graph, and such an ideal is known as the edge ideal of the resulting graph.
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<br>
I will mainly talk about the regularity of edge ideals, and present our graph theoretical approach to the regularity. I shall present some graph invariants and structural properties that are related to the regularity.
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<span class="gmail-im">(This is a joint work with Yusuf Civan, Suleyman Demirel University)
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Time: 15.40,<br>
Place: Mathematics Department Seminar Room SA-141.</span></font>
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<p><span style="font-family: Arial,Helvetica,sans-serif;">Best regards,<br>
</span></p>
<p><span style="font-family: Arial,Helvetica,sans-serif;"><br>
</span></p>
<p><span style="font-family: Arial,Helvetica,sans-serif;">Anargyros Katsampekis</span><br>
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