What we've done so far

Monday August 26th
  • Overview
  • mxn matrices correspond 1:1 to linear transformations R^n -> R^m. In particular this is why matrix multiplication is associative.
  • Friday August 30th Fields, vector spaces (as having binary, unary, and nullary operations). One thing slightly wrong, correcting it a homework question.
    Wednesday September 4th Subspaces, definition of independence/spanning/basis in terms of the natural map from F^n being 1:1/onto/both.
    Friday September 6th If I is independent, and S (finite) spans, then we can find a basis containing I, and inside I union S. Many many corollaries.
    Monday September 9th Exchange property for bases, therefore they all have the same size.
    Wednesday September 11th Nullity plus rank theorem, examples of 2x2 invertible matrices.
    Friday September 13th Systems of linear equations, Lights Out
    Monday September 16th Hom(V,W), which Curtis calls L(V,W). Dual spaces.
    Wednesday September 18th Quotient spaces.
    Friday September 20th More quotient spaces, and a little bit on cohomology of graphs (special topic).
    Monday September 23rd Direct sums of spaces and maps.
    Wednesday September 25th Double duals, dual bases, transposes.
    Friday September 27th Pairings between two vector spaces, and the relation to dual spaces. Cokernels. Duality exchanges 1:1ness and ontoness.
    Monday and Wednesday September 30th, October 2nd Review for midterm #1.
    Friday October 4th Midterm #1.
    Monday October 7th Properties of determinant. Repeated rows gives 0 => switching rows negates. Reverse implication also true, as long as 1+1 isn't 0.
    Wednesday October 9th Proof that there exists a unique function "det" with the given properties.
    Friday October 11th Eigenvalues. Algebraically closed fields.
    Monday October 14th Induced maps on quotient spaces by T-invariant subspaces. Every matrix can be upper triangularized (over an algebraically closed field). Generalized eigenspaces.
    Wednesday October 16th V is the direct sum of its generalized eigenspaces.
    Friday October 18th Nilpotent matrices. Statement of Jordan Canonical Form. Viewing a nilpotent matrix as people walking off a cliff in a bunch of independent queues.
    Monday October 21st More JCF: another construction of the good basis for nilpotent transformations. Uniqueness of JCF.
    Wednesday October 23rd Yet more JCF. Every transformation is the sum of a diagonalizable and a commuting nilpotent part.
    Friday October 25th Side topic: finitely generated modules over (certain) rings. The classification of finite abelian groups.
    Monday October 28st Bilinear forms. Gram matrices. How Gram matrices change under change of basis.
    Wednesday October 30th Hints on the homework. Diagonalizable matrices are those that satisfy squarefree polynomials. "Nondegeneracy" of bilinear forms.
    Friday November 1st Bilinear forms and perps.
    M, W, F, W November 4th, 6th, 8th, 13th Reviewing for, taking, and going over the midterm.
    Friday November 15th Yet another proof of the decomposition into generalized eigenspaces. Splitting spaces with a symmetric bilinear form into their radical and a nondegenerate space.
    Monday November 18th Sylvester's Law of Inertia: bilinear forms over real or complex spaces have orthogonal bases that are almost normal -- the norms can be taken to be 0, 1, or -1.
    Wednesday November 20th The Clever™ algorithm for web searches. See the original paper, in PostScript, or in PDF.
    Friday November 22nd Introducing tensors.