Phys 401, Fall 2018
Topics Covered in Each Lecture
Lecture Number |
Date |
Content |
Corresponding Reading material |
1 |
Sep. 18 |
Review of Classical mechanics (CM): States, observables, and measurement in CM, Newtonian formulation of classical dynamics, conservative forces, one-dimensional gravitation fall, energy conservation |
Pages 75-76 of Shankar |
2 |
Sep. 20 |
Lagrangian formulation of CM, action functional & the least action principle, Derivation of the Euler-Lagrange equation from least action principle in one dimension, Application to standard Lagrangian |
Pages 77-83 of Shankar |
3 |
Sep. 25 |
Euler-Lagrange equations in n
dimensions, from Cartesian to generalized coordinates, application to simple
pendulum, the central forces in two dimension, conservation of angular
momentum; Symmetry in CM and Nöther’s theorem,
translational symmetry and momentum conservation, rotational symmetry and
angular momentum conservation, time-translation symmetry and conservation of
energy |
- |
4 |
Sep. 27 |
Hamiltonian formulation of CM,
the states and phase space of a classical system in Hamiltonian formulation,
Hamilton’s equations of motion, observables in Hamiltonians formulation of
CM, rate of change of the value of an observable, Poisson bracket and its
properties, fixing states and making the observables dynamical |
Pages 86-92 of Shankar |
5 |
Oct. 02 |
Canonical transformations:
Definition, characterization, an example, infinitesimal canonical
transformation and their generator, symmetries and Nöther’s
theorem in Hamiltonians formulation of CM |
Pages 92-104 of Shankar |
6 |
Oct. 04 |
Review of linear algebra: Complex vector spaces, subspaces,
span, finite-dimensional vector spaces, linear independence, (algebraic or
Hamel) basis, dimension of a finite-dimensional vector space, linear
operators, their domain and range, vector-space isomorphisms |
Pages 1-7 of Shankar |
7 |
Oct. 09 |
The unique representation theorem, classification of
finite-dimensional complex vector spaces using their dimension, the dual
space of a vector space and the dual basis, matrix representation of elements
of a finite-dimensional vector space and its dual |
- |
8 |
Oct. 11 |
The Euclidean inner product on C^n,
inner product and complex inner-product spaces, examples of inner-product
spaces, L^2-inner product on the space of continuous functions defined in an
interval, unit and orthogonal elements and subsets of an inner-product space,
orthonormal subsets and bases, the matrix representation of vectors and
linear operators in an orthonormal basis, the existence of orthonormal bases
for a finite-dimensional vector spaces (Gram-Schmidt process) |
Pages 7-16 of Shankar |
- |
Oct. 13 |
Exam 1 |
|
9 |
Oct. 16 |
Riesz lemma
(Representation Theorem) in finite-dimensions and Dirac’s bra-ket notation, matrix representation of linear operators
acting in a finite-dimensional inner product space, matrix representation in
an orthonormal basis; Unitary operators mapping an inner product space onto
another, inverse of a unitary operator, unitary equivalent inner product
spaces, characterization of unitary operators as isomorphisms
mapping orthonormal bases to orthonormal bases. |
Pages
16-29 of Shankar |
10 |
Oct. 18 |
The matrix representation of unitary operators in an
orthonormal basis, the unitary matrices and unitary groups U(n), Symmetric
operators, Hermitian (self-adjoint) operators in
finite-dimensions, the matrix representation of Hermitian operators in an
orthonormal basis and Hermitian matrices, the adjoint
of a linear operator mapping a finite-dimensional inner-product space V to V,
properties of the adjoint. |
Pages
16-29 of Shankar |
11 |
Oct. 23 |
Hermitian and unitary operators represented by diagonal
matrices in an orthonormal basis, properties of the eigenvalues and
eigenvectors of Hermitian and unitary operators, normal operators, statement
of the spectral theorem for normal operators in finite-dimensions, spectral
representation of a normal operator, Hermitian (unitary) operators as normal
operators with real (unimodular) eigenvalues,
change of bases and orthogonalization of the matrix
representation of a normal operator. |
Pages
30-43 of Shankar |
12 |
Oct. 25 |
Application of the spectral theorem for a Hermitian
operator acting in C2,
Degenerate eigenvalues, degeneracy subspaces, the associated projection
operators and the orthogonal direct-sum decomposition of the inner-product
space |
Pages
30-43 of Shankar |
13 |
Oct. 30 |
The existence of a basis consisting of eigenvectors of a
pair of commuting Hermitian operators in finite dimensions, functions of a
normal operator acting in a finite-dimensional inner-product space, unitary
operators as functions of Hermitian operators |
Pages
43-46 of Shankar |
14 |
Nov. 01 |
Convergence of sequences in an inner-product space V,
closure of a subset of V, limit of a function f
mapping V to an inner-product space W, continuity of f
at a point of its domain, continuous functions f:V->W, derivative of a
function g:R->V, Cauchy sequences and the definition of a Hilbert space;
Postulates of QM for systems with a finite-dimensional state space: Basic
postulate: Representation of quantum systems by a Hilbert space and a
Hermitian operator, Kinematical aspects: (Pure) States, state space,
observables, and projection axiom |
Pages
116-127 of Shankar |
15 |
Nov. 06 |
Review of the projection axiom, outcomes of a measurement
and their probabilities, the expectation value and uncertainty in measuring
an observable, the relation between reality of the spectrum of a linear
operator and its Hermiticity, the proof that zero
uncertainty is achieved only and only by the eigenstates, Instantaneous repetition of a measurement, Application for
a system with a 3-dimensional Hilbert space and an observable with two
eigenvalues. |
Pages
127-129 of Shankar |
16 |
Nov. 08 |
Compatible observables; Dynamical Aspects of QM: The
time-dependent Schrödinger equation, the invariance of the inner product of
two evolving states, the time-evolution operator and its unitarity. |
Page
129-131 & 145-146 of Shankar |
- |
Nov. 12 |
Exam 2 |
|
17 |
Nov. 13 |
Basic properties of time-evolution operator for
time-independent Hamiltonian operators, time-evolution operator for a
time-independent Hamiltonian operator, stationary states, computation of
expectation values of spin observables for a two-level system. |
Page
145-147 of Shankar |
18 |
Nov. 15 |
The Dyson series for the evolution operator of
time-dependent Hamiltonians, time-ordering operation, quantum dynamics in the
Heisenberg picture, Heisenberg-picture observables, the Heisenberg equation
and its correspondence with Hamilton’s equations of motion, Dirac’s classical
to quantum correspondence, the antisymmetry,
linearity, Jacobi identity, and Leibnitz rule property of the commutator. |
Pages
71-75 & 80-84 of Sakurai’s “Modern Quantum Mechanics” |
19 |
Nov. 20 |
Dirac’s canonical quantization prescription, the canonical commutation relations; The vector space of classical observables with the Poisson bracket and the vector space of anti-Hermitian operators with (iħ)-1 time the commutator as Lie algebras, The definition of a Lie algebra, generators of finite-dimensional Lie algebras and its structure constants, representations of a Lie algebra, faithful and unitary representations, the Heisenberg Algebra hd. The proof that hd does not have a finite-dimensional faithful unitary representations. |
- |
20 |
Nov. 22 |
Schauder bases of
an infinite-dimensional inner-product space, separable inner-product spaces,
orthonormal Schauder bases of an
infinite-dimensional separable inner product space, the Hilbert space of
square-summable sequences (l2) as the
principal example of an infinite dimensional separable Hilbert space, the
uniqueness theorem for infinite dimensional separable Hilbert spaces,
Representing the Heisenberg Algebra h1 in l2
, space of square-integrable functions L2(D)
where D is an interval of real numbers, Representing the Heisenberg Algebra h1 in L2(R): The position and momentum operators. |
- |
21 |
Nov. 27 |
The domains of the operators X, K, and P, he proof that they
are are symmetric operators; Adjoint
of a linear operator in infinite dimensions, the distinction between the
notions of symmetric operator and Hermitian (self-adjoint)
operator; spectrum of Hermitian and unitary operators as the set of
approximate eigenvalues, the point and continuous spectrum of a Hermitian or
unitary operator, the evaluation map and the spectral problem for X, the
Dirac delta function as “generalized eigefunctions”
of X, their completeness and orthonormality
relations, position basis, spectral representation of X and functions of X;
The spectral problem for K, the orthonormality and
completeness relation for the “generalized eigrnfunctions”
of K, spectral representation of K and functions of K. |
Pages
57-70 of Shankar |
22 |
Nov. 29 |
Spectral theorem for Hermitian and unitary operators acting
in an infinite-dimensional Hilbert space, the resolution of identity and the
spectral representation of Hermitian and unitary operators, the measurement
axiom for quantum system with an infinite-dimensional Hilbert space, the
probability of the outcome of a measurement of an observable, its expectation
value and uncertainty, the probability density; the measurement of position
and momentum operators, the position and momentum wave functions, probability
density of localization in space. |
Pages
67-70 of Shankar |
23 |
Dec. 04 |
Superposition principle, the position and momentum
representation of observables, quantization of a free particle moving on a
straight line, the factor-ordering problem, the system defined by the
simplest factor-ordering for the Hamiltonian of a free particle moving on a
straight line, the spectrum and (generalized) eigenfunctions
of the Hamiltonian operator H=P2/2m. |
Pages
151-152 of Shankar |
24 |
Dec. 06 |
Time evolution of the eigenstates of the Hamiltonian for a
free particle, their position wave function and
plane waves, the position wave function for a general evolving state:
calculation of the propagator for the free particle. Evolution of a free
particle with an initial Gaussian position wave function, the time-dependent
Schrödinger equation in position representation for a particle interacting
with possibly time-dependent vector and scalar potentials in one dimension,
the time-independent Schrödinger and the spectrum of the Hamiltonian operator |
Pages
152-157 of Shankar |
- |
Dec. 08 |
Exam 3 |
|
25 |
Dec. 11 |
Interpreting superposition of definite momentum states of
the free particle using the standard Bohr/Copenhagen interpretation and
Everett’s many world interpretation; Particle in an infinite potential well
in one dimension: Classical dynamics, quantization and the Hamiltonian
operator, solution of the time-independent Schrödinger equation, the Hilbert
space, energy spectrum, energy eigenfunctions, and
propagator; Differences between the classical and quantum behavior: Existence
of a discrete set of possible outcomes of energy measurements, resistance of
the quantum particle to be squeezed into a narrow infinite potential well |
Pages
157-164 of Shankar |
26 |
Dec. 13 |
Particle in a half infinite – half finite square potential
barrier: Determination of the energy spectrum (point and continuous spectra)
and energy eigenstates, physical interpretation of the generalized eigenfunctions associated with points of the continuous
spectrum as scatting states, calculation of the reflection amplitude and the
scattering phase shift |
- |
27 |
Dec. 18 |
Finite rectangular barrier potential, scattering solutions,
reflection and transmission amplitudes, transfer matrix, tunneling |
- |
28 |
Dec. 20 |
Cauchy-Schwartz inequality and the Heisenberg uncertainty
principle, the minimum uncertainty (quasi-classical) states as eigenstates of
a non-Hermitian operator, states with minimal product of position and
momentum uncertainties in one dimension |
Pages
16-17 & 237-241 of Shankar |
Note: The pages from the textbook listed above may not include some of the subjects covered in the lectures.