This thesis concerns sets of points in the finite projective space PG(n,q) that are combinatorially identical to quadrics. A quadric is the set of points of PG(n,q) whose coordinates satisfy a quadradic equation, and the term quadral is used in this thesis to mean a set of points with all the combinatorial properties of a quadric. Most of the thesis concerns the characterisation of certain sets of subspaces associated with quadrals. Characterisations are proved for the external lines of an oval cone in PG(3,q), of a non-singular quadric in PG(4,q), q even, and of a large class of cones in PG(n,q), q even. Characterisations are also proved for the planes meeting the non-singular quadric of PG(4,q) in a non-singular conic, and for the tangents and generator lines of this quadric for q odd. The second part of the thesis is concerned with the intersection of ovoids of PG(3,q). A new bound is proved on the number of points two ovoids can share, and configurations of secants and external lines that two ovoids can share are determined. The structure of ovoidal fibrations is discussed, and this is used to prove new results on the intersection of two ovoids sharing all of their tangents. / Thesis (Ph.D.) -- University of Adelaide, School of Mathematical Sciences, 2008

Thesis (PH. D)--University of Chicago, 1916. / "Private edition, distributed by the University of Chicago Libraries, Chicago, Illinois." "Reprinted from Giornale di matematiche di Battaglini Vol. LIV, 1916." Includes bibliographical references. Also available on the Internet. Also issued online.

Thesis (M. Phil.)--University of Hong Kong, 2001. / Includes bibliographical references (leaves 68-70).

Thesis (doctoral)--Friedrich-Wilhelms-Universität zu Berlin, 1926. / "Sonderabdruck aus: Zeitschrift für angewandte Mathematik und Mechanik, Bd. 6, 1926"--P. [1]. Vita. Includes bibliographical references.

Thesis (Ph. D.)--University of Chicago, 1903. / Life. "Reprinted from the Transactions of the American mathematical society, vol. 5, no. 3."

Thesis (Ph. D.)--University of Chicago, 1935. / Vita. Lithoprinted. "Private edition, distributed by the University of Chicago libraries, Chicago, Illinois."

Thesis--Université de Liege. / "Extrait des Mémoires de la Société royale des sciences de Liége, 3e série, tome 20."

Thesis (Ph. D.)--University of Oregon, 2003. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 106-108). Also available for download via the World Wide Web; free to University of Oregon users.

Using tropical methods, we study the problem of compactifying the moduli space of six general lines in the projective plane. In particular, we show that the log canonical compactification is Kapranov’s Chow quotient compactification. / text

abstract / Mathematics / Doctoral / Doctor of Philosophy