algebraic geometry seminars

[beorchia at units.it]

Seminar on  "Cylinders through 5 Points"

speaker : dr. Matteo Gallet (RICAM Linz)

date: June 12, 2014

venue: 12.00,   seminar room, 3rd floor, Dipartimento di Matematica e  
Geoscienze, via Valerio 12 bis



Abstract : For 5 points in R^3, there exist in general 6 circular
cylinders passing through them (including complex solutions). Based on
computational experiments, Lichtblau conjectured in 2007 that if the
number of cylinders is infinite, then the 5 points are located on two
parallel lines. We give a proof of this conjecture without computers,
using classical invariant theory and a novel use of real structures of
algebraic varieties.


Seminar on  "The Genus of the Configuration Curve of a Kinematic Loop with
6 Revolute Joints (joint work with G. Hegedues, Z. Li, and H.-P.
Schröecker)"

speaker : prof. dr. Josef Schicho (RICAM Linz)

date: June 13, 2014

venue: 10.00,   seminar room, 3rd floor, Dipartimento di Matematica e  
Geoscienze, via Valerio 12bis



Abstract: We consider mechanisms consisting of 6 links cyclically
connected by rotational joints. In general, such linkages are not
movable. It is an open problem to characterize movable 6R linkages. In
this talk, we present a method that allows to give a sharp bound for
the genus of the set of motions, assuming that this set is a curve.

Everyone welcome.


Valentina Beorchia, PhD
Dipartimento di Matematica e Geoscienze
Universita' degli Studi di Trieste
Via Valerio 12/1
34127 Trieste, Italia

Stanza 236, II piano
e-mail: beorchia at units.it
tel. studio (++) 040 558 2656
tel. segreteria Dip.: (++)040 558 2635 oppure 2618
fax: (++) 040 558 2636

http://www.dmi.units.it/~beorchia/