Math 320, Spring 2015

Topics Covered in Each Lecture

 

 

Lecture Number

Date

Content

Corresponding Reading material

1

Feb. 10 Vector spaces over real and complex numbers, examples Fn, F, and F[x]; uniqueness of the zero vector and additive inverse of a vector, 0.v=0, a.0=0, (-1).v=-v; subspace, examples  Pages 1-14 of Axler

2

Feb. 12 Sum and direct sum of subspaces, characterization theorems for direct sum; span of a subset, Span(A) is the smallest subspace containing A.  Pages 14-22 of Axler

3

Feb. 17 Finite- and infinite-dimensional vector spaces, linear-independence  Pages 22-27 of Axler

4

Feb. 24 Basis of a vector space, reduction of spanning lists to a bases, the extension of linearly independent lists to bases, and existence of bases in a finite-dimensional vector space, the dimension of a finite-dimensional vector space  Pages 27-31 of Axler

5

Feb. 26 Properties of the dimension of a finite-dimensional vector space, its subspaces, and their sum; linear maps, their domain and range, examples Pages 31-39 of Axler

6

Mar. 03 Linear maps belonging to L(Fn,F); Image and inverse image of subspaces under linear maps, range and null space, characterinzation of 1-to-1 linear maps using their null space, dimension theorem and some of its applications Pages 39-47 of Axler

Quiz 1

Mar. 04    

7

Mar. 05 Matrix representations of a linear map, summation and scalar multiplication of matrices, vector space of m × n matrices, multiplication of matrices; invertible linear maps and isomorphic vector spaces Pages 48-55 of Axler

8

Mar. 10 Isomorphism as an equivalence relation, classification of finite-dimensional vector spaces, Theorem: For a finite-dimensional vector space V and linear operators L:V->V with domain V, one-to-oneness is equivalent to ontoness. Ismorphism between L (V,W) and Mat(m,n,F) where n=dim(V) and m=dim(W); Motivation for eigenvalue problem, invariant subspaces, one-dim invariant subspaces, eigenvalues and eigenvectors of a linear operator. Pages 55-58 & 75-77 of Axler

9

Mar. 12 Invariant subspaces associated with the eigenvalues of a linear map, geometric multiplicity of eigenvalues,  linear independence of a list of eigenvectors with distinct eigenvalues, dimension as the upper bound on the number of eigenvalues, linear maps with as many distinct eigenvalues as the dimension, characterization of eigenvalues a of a linear map A in terms of non-invertibility of A-a I, the point spectrum, the existence of eigenvalues for linear maps acting in a finite-dimensional complex vector space Pages 78-82 & 87-90 of Axler

Quiz 2

Mar. 13    

10

Mar. 17 Upper-triangular matrices and matrix representation of linear maps acting in a finite-dimensional vector space Pages 83-87 of Axler

11

Mar. 18 Extra Lecture: Inner-product spaces, norm and distance defined by an inner product, unit and orthogonal vectors, orthonormal subsets of an inner-product space, Pythagorean theorem and Cauchy-Schwarz inequality Pages 97-104 of Axler

12

Mar. 19 Triangular inequality, orthonormal lists and bases, Gram-Schmidt process, existence of orthonormal bases, upper-triangular matrix representation of a linear operator in an orthonormal basis. Pages 105-111 of Axler

13

Mar. 24 Pre-Exam Review Session  

14

Mar. 26 Projection operators acting in a vector space V and the associated direct sum decompositions of V, orthogonal complement of a subspace of V and the associated direct-sum decomposition of V Pages 111-112 of Axler

Exam 1

Mar. 28    

15

Mar. 31 Orthogonal projection operators and orthogonal direct sum decompositions, dual space of a vector space, the one-to-one correspondence between dual vector and vectors in a finite-dimensional inner-product space that is realized by the inner product (Riesz Lemma) Pages 112-118 of Axler

16

Apr. 01 Extra Lecture: The adjoint of a linear operator, its properties, and matrix representations. Pages 118-121 of Axler

17

Apr. 02 The relation between the null space and range of a linear operator with those of its adjoint; Self-adjoint operators and the reality of their eigenvalues, Lemma on expressing <Tu,w> in terms of <Tv,v> for 4 specific choices of v for complex inner-product spaces, the polarization formula, the characterization of self-adjoint operators acting in a complex inner-product space in terms of the reality of <Tv,v> for all v; A sufficient condition for a self-adjoint operator acting in a real inner-product spaces to be zero, the polarization formula for the inner products on a real vector space Pages 120 & 127-130 of Axler

Spring Break

     

18

Apr. 14 Normal operators and their characterization, the properties of the eigenvectors of a normal operator, the complex spectral theorem for normal operators in finite dimensions Pages 130-134 of Axler

19

Apr. 16 Statement of the spectral theorem in terms of orthogonal projection operators, the spectral representation of normal and self-adjoint operators, functions of normal and self-adjoint operators See for example Hoffman and Kunze pages 335-337

Quiz 3

Apr. 17    

20

Apr. 21 Positive operators and their spectral representation, the existence of a unique positive square of a positive operator, isometries of an inner-product space and their basic properties Pages 144-150 of Axler

21

Apr. 22 Extra Lecture: Spectral theorem for isometries (unitary operators) acting in a finite-dimensional complex inner-product space; the relationship between isometries and self-adjoint operators, Matrix representation of isometries in orthonormal bases, the unitary matrices; Polar and singular-value decompositions Pages 150-157 of Axler

22

Apr. 28 Generalized eigenvectors, null space and range of powers of a linear operator acting in a finite-dimensional vector space, nilpotent operators, the algebraic multiplicity of eigenvalues and their equivalence to the number of time an eigenvalue appears as the diagonal entries of any upper-triangular representation of the operator Pages 163-172 of Axler

23

Apr. 29 Extra Lecture: A characterization theorem for diagonalizable operators; Characteristic polynomial, the Cayley-Hamilton Theorem, and its application in computing large powers of square matrices; Direct sum decomposition of a vector space into the subspaces of generalized eigenvectors of a linear operator Pages 172-175 of Axler

24

May 05 Review and Problem Session  

Quiz 4

May 07    

25

May 12 Upper-triangular matrix representation of nilpotent operators, block-diagonal upper-triangular matrix representation of linear operators acting in a complex vector space, construction of square roots of I+N and T where N is nilpotent and T is invertible; minimal polynomial of a linear operator Pages 175-179 of Axler

26

May 13 Extra Lecture: Properties of the minimal polynomial of a linear operator Pages 180-182 of Axler

27

May 14 Jordan form of a Nilpotent operator, Jordan canonical form of a general linear operator Pages 183-187 of Axler

Exam 2

May 18    

Make-up Exam

May 25    

Note: The pages from the textbook listed above may not include some of the subjects covered in the lectures.