CS G714: Theory of Computation

Spring 2008

Mailing list

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Tentative Calendar

The reading assignments list section numbers from the second edition of Sipser's text ([S]) and lecture numbers from Kozen's text ([K]).  The numbers within the parenthesis are the corresponding sections and chapters in the first edition.
 
 
 Week  Topic Problem Sets
Handouts
Reading
Jan 7
Administrivia
Introduction
The Church-Turing Thesis;
Variants of Turing machines
1 out Problem Set 1
POW 1
[S] 1, 2, 3.1-3.3
Jan 14
Decidability
Decidable problems concerning regular and context-free languages
The Halting Problem

POW 2
[S] 4.1-4.2
Jan 21
Reducibility
Reductions
Post's Correspondence Problem
1 due; 2 out Problem Set 2
POW 3
[S] 5.1-5.3
Jan 28
Time Complexity
Lower bounds for single-tape Turing machines
P and NP

POW 4
[S] 7.1-7.3
[K] 1
Feb 4
NP-Completeness
Poly-time reductions
Cook-Levin Theorem
2 due; 3 out
Sample Solutions to PS1
[S] 7.4-7.5
Feb 11
NP-Completeness reductions
Space Complexity

Savitch's Theorem

POW 5
[S] 8.1, 8.4
[K] 2-3
Feb 18
Space Complexity, contd.
Immerman-Szelepcsenyi Theorem
Logspace Computability
3 due; 4 out
Sample Solutions to PS2
POW 6
[S] 8.4-8.5
[K] 4-6
Feb 25
Space Complexity, contd.
PSPACE and PSPACE-completeness

Problem Set 4
POW 7 & 8
[S] 8.2-8.3, 10.2
[K] 8, 13, C
Mar 3
Spring Break

Sample Solutions to PS3


Mar 10
Alternation
Alternating Turing Machines
The Polynomial-Time Hierarchy
Hierarchy Theorems
Separation results
4 due
Midterm out
Midterm
[S] 9.1-9.2, 10.3
[K] 7, 9
Mar 17
Probabilistic Complexity
The class BPP
Midterm due
Sample Solutions to PS4
[S] 10.2
[K] 8, 13
Mar 24
Interactive Proof Systems
Graph nonisomorphism
IP = PSPACE
5 out
Problem Set 5
POW 9
[S] 10.4
[K] 15-17
Mar 31
Probabilistically checkable proofs (PCP)
Definition of the model
Hardness of approximation
5 due;6 out Midterm sample solutions

[K] 18-19
Apr 7
More on PCP
NP is subset of PCP(poly(n),1)
One-way functions and basic crypto

Problem Set 6
POW 10 & 11
[K] 19-20
[S] 10.6
Apr 14
Recursion Theorem and Applications
Decidability of Logical Theories
6 due
POW 12

[S] 6.1-6.2
[K] 21, 33-34
Apr 21
Finals week

Sample Solutions to PS5
Sample Solutions to PS6
Final
Sample Solutions to Final


 

Note: All handouts are in PDF.

Interactive Proofs and the PCP Theorem

The PCP Theorem and Hardness of Approximation
A course at University of Washington, V. Guruswami and R. O'Donnell, Autumn 2005

The PCP theorem by gap amplification
I. Dinur, JACM 2007

On Dinur's Proof of the PCP Theorem
J. Radhakrishnan and M. Sudan

Complexity Theory
Notes from course taught at University of Maryland, College Park, Jonathan Katz, Fall 2005