Fall 2025 MAT 550: Introduction to Probability
ScheduleMW 3:30am-4:50pm Physics P127
InstructorRobert Hough
Office hoursTh 7-8 in MLC, F 9am-11pm in Math Tower 4-107.
Description Introduction to probability theory: independence, laws of large numbers, central limit theorems, martingales, Markov chains, and a selection of other topics such as ergodic theory, Brownian motion, random walks on graphs and groups, percolation, mixing times, randomized algorithms.
TextbookRick Durrett. Probability: theory and examples. Cambridge University Press. 5th Edition.
Supplementary TextbooksAlon and Spencer. The probabilistic method. John Wiley and Sons (2016).
Morters and Peres. Brownian Motion. Cambridge University Press (2010).
GradingThe course grade is based upon the written homework. The problem numbers are from Durrett.

Syllabus/schedule (subject to change)
Mon 8/251. Random variables and integration Durrett 1.1-1.5
Wed 8/272. Expected value, Carathéodory extension theorem Durrett 1.6-1.7, A.1
Mon 9/1 No class - Labor day
Wed 9/33. Kolmogorov extension theorem Durrett A.2-A.5
Mon 9/84. Weak law, Borel-Cantelli Durrett 2.1-2.3
Wed 9/105. Strong law Durrett 2.4-2.7
Mon 9/156. Characteristic functions Durrett 3.1-3.3
Wed 9/177. Central limit theorem, local limit theorem Durrett 3.4-3.6
Mon 9/228. Poisson process, stable laws Durrett 3.7-3.10
Wed 9/249. MartingalesDurrett 4.1-4.3
Mon 9/2910. Convergence of martingales, Doob's inequality Durrett 4.4-4.6
Wed 10/111. Backwards martingales, optional stopping theorem Durrett 4.7-4.9
Mon 10/612. The probabilistic method, 2nd moment methodAlon and Spencer, Chaps 2,4,5
Wed 10/813. Correlation inequalities, Azuma's inequality, Chernoff's inequality Alon and Spencer, Chaps 6,7,A
Mon 10/13 No class - Fall Break
Wed 10/1514. Markov chains, recurrenceDurrett 5.1-5.3
Mon 10/2015. Stationary measure, asymptotic behaviorsDurrett 5.4-5.6
Wed 10/2216. Tail behaviors Durrett 5.7-5.8
Mon 10/2717. Birkhoff ergodic theorem Durrett 6.1-6.3
Wed 10/2918. Subadditive ergodic theorem Durrett 6.4-6.5
Mon 11/319. Construction of Brownian motion Durrett 7.1, Morters and Peres 1.1-1.4
Wed 11/520. Strong Markov property Durrett 7.2-7.3, Morters and Peres 2.1-2.4
Mon 11/1021. Martingales, Itô's formula Durrett 7.5-7.6
Wed 11/1222. Harmonic functions, Dirichlet problem, occupation measureMorters and Peres 3.1-3.4
Mon 11/1723. Hausdorff dimension, mass distribution principle Morters and Peres 4.1-4.4
Wed 11/1924. Donsker's theorem, CLT for martingales and stationary sequencesDurrett 8.1-8.3
Mon 11/2425. Brownian bridge, law of iterated logarithm Durrett 8.4-8.5
Wed 11/26 No class - Thanksgiving
Mon 12/126. Heat equation, Feynman-Kac formulaDurrett 9.1-9.4
Wed 12/327. Occupation times, Schrödinger equation, local timeDurrett 9.5-9.8, Morters and Peres 6.1-6.2
Mon 12/828. Ray-Knight Theorem, equilibrium measure Morters and Peres 6.3-6.4, 8.1-8.2

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