Seminar CGTA, 15.9.2009.

• 11. Septembar,  2009
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Sastanak CGTA seminara, utorak, 15. 9. 2009, 18:00 - 20:00, Matematički fakultet, sala 821, 5. sprat

Bruno Benedetti (TU Berlin): LOCALLY CONSTRUCTIBLE SPHERES

Locally constructible (LC) simplicial 3-spheres are the spheres obtainable from a tree of tetrahedra by repeatedly identifying two adjacent boundary triangles. This notion was introduced in 1995 by two physicists, who conjectured that all spheres are LC. (The problem is important for the convergence of models for 3D quantum gravity.) We solved the conjecture negatively, showing the existence of non-LC d-balls and d-spheres for each d > 2. We present a characterization of the LC property using classical notions in combinatorial topology. This is joint work with Günter Ziegler.

Očekujemo vrlo interesatno predavanje koje povezuje teoriju konveksnih politopa sa 3 i 4-dimenzionalnom topologijom.

Interdisciplinarnost teme kao i univerzalni značaj razmatranih objekata (konveksni politopi, triangulacije 3-sfera) čine predavanje posebno interesatnim za mlade matematičare.

Preprint vezan za predavanje se može naći na

http://xxx.lanl.gov/abs/0902.0436

 Predavanje će se održati u sali 821 na 5. spratu MF BGD.

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