MAT315H1S: Introduction to Number Theory
Winter 2021
University of Toronto


I.    Instructor and Teaching Assistants

Course Instructor

Name: Stephen Kudla

Email: [email protected]

Office Hours: W 8-9pm


TA’s

Name: Enrique Nunez-Lon-wo

Email: [email protected]

Office Hours: = tutorial hours


Name: Georgios Papas

Email: [email protected]

Office Hours: = tutorial hours


Name: Shuyang Shen

Email: [email protected]

Office Hours: =tutorial hours


Name: Artane Siad

Email: [email protected]

Office Hours: = tutorial hours


II.    Course Overview

Course Description

Introduction to Number Theory

Elementary topics in number theory: arithmetic functions; polynomials over the residue classes modulo m, characters on the residue classes modulo m; quadratic reciprocity law, representation of numbers as sums of squares.


Prerequisites

(MAT223H1/MATA23H3/MAT223H5/MAT240H1/MAT240H5, MAT235Y1/MAT235Y5/(MATB41H3, MATB42H3)/MAT237Y1/(MATB41H3, MATB42H3, MATB43H3)/MAT237Y5,MAT246H1/CSC236H1/CSC240H1)/MAT157Y1/MAT157Y5/MAT247H1/MAT247H5


Course Objectives

This course will provide a basic knowledge of elementary number theory, a subject that is important in many areas of mathematics, computer science, cryptography and security, and elsewhere. We will cover material from Chapters 1—7 of the text by Jones and Jones and will pick up some additional material to be covered in handouts. The main topics are the following:

1. divisors, Euclidean algorithm, gcd(a,b), lcm(a,b).

2. primes, factorization, Prime Number Theorem (statement), Fermat and Mersenne primes,

3. modular arithmetic, congruences, Chinese Remainder Theorem,

4. computing powers and roots mod m, intro to RSA

4. arithmetic mod p for p a prime, Fermat's little Theorem, Wilson's Theorem, primality testing, pseudo-primes and Carmichael numbers

5. (\Z/n\Z)^x, the Euler \phi function, \phi(n).

6. structure of (\Z/p^e\Z)^x, primitive roots

7. quadratic congruences, quadratic reciprocity, Legendre symbol

Additional topics as time permits selected from:

-- the Riemann zeta function, Euler product, Riemann hypothesis,

-- irrational and transcendental numbers, Liouville numbers

-- the abc conjecture.


Textbooks/ Course Reading


Required Textbook:

G. Jones and J. M. Jones, Elementary Number Theory, Springer, ISBN-13:978-3540761976.

(An ebook version of this text is available.)


Additional references:

(These books are not required but are nice sources of additional material and perspectives.)

J. Silverman, A Friendly Introduction to Number Theory, Pearson, 4th ed., 2012, ISBN-13:978-0321816191.

A.Granville, Number Theory Revealed: An Introduction, Amer. Math. Soc., 2019.

K. Rosen, Elementary Number Theory, 6th ed., Addison Wesley, ISBN-13:978-0321500318.


Course Website: The address for Quercus course site is: https://q.utoronto.ca/courses/201925


How this course is organized:

Each week there will be three 1 hour lectures: MWF, 10:10—11:00. [All times are Toronto times.]

Each student should enroll in a tutorial section.


Due to the Covid-19 pandemic, all components of the course will be delivered online synchronously on BB Collaborate. A link will be provided through the Quercus course site.

Lectures will be recorded and posted on the Quercus course site following each class.

Additional material will be posted on the Quercus course site.


Tutorials will start the week of Jan 11th and will be synchronous, so students will be expected to attend the tutorial at the scheduled time for their registered section.

The course was originally scheduled in a combined live classroom/online format. Now that it is running online only, the lecture sections 0101 (previously classroom) and 9101 are now the same.


Similarly, for the tutorials, so that there are now 6 tutorial sections:

W11-12: 0101 = 9101, W11-12: 0102 = 9102, W12-1: 0201 = 9201,

F11-12: 0301 = 9301, F12-1: 0401 = 9401, F1-2: 0501 = 9501.


There will be two Midterm Exams, one during week 5 and one during week 10.

There will be weekly homework. These assignments will be posted after the Monday lecture and will be collected on Crowdmark before the start of lecture the following Monday (i.e., due at 10:00am).

Please note: No late homework will be accepted.


Technical Requirements

In order to participate in this course, students will be required to have:

•    Reliable internet access. It is recommended that students have a high speed broadband connection (LAN, Cable, or DSL) with a minimum download speed of 5 Mbps.

•    A computer satisfying the minimum technical requirements (https://www.viceprovoststudents.utoronto.ca/covid-19/tech-requirements-online-learning/)

Other recommended items include headphones, microphone, webcam, and a tablet or printer.

If you are facing financial hardship, you are encouraged to contact your college or divisional registrar (https://future.utoronto.ca/current-students/registrars/) to apply for an emergency bursary.


III.    Evaluation/ Grading Scheme

Mark Breakdown

Homework Assignments 40%

Term Test 1 15%

Term Test 2 15%

Final Assessment 30%


Homework Assignments

There will be 10 homework assignments, of which the three with lowest grades will be dropped.

(Late submissions will receive a mark of zero.).

The due dates will be at 10am sharp on the Mondays of weeks 2 – 5, weeks 6—10, and week 12.


Midterm Tests

There will be two Midterm tests which will be available for 24 hours to allow a reasonable window for students in all time zones to write.


Midterm Test 1 will be on February 10, 7pm ET to February 11 7pm ET

Midterm Test 2 will be on March 24, 7pm ET to March 25, 7pm ET


Final Assessment

The final assessment will be held during the final assessment period in April 2021 and will be scheduled by the registrar. Information about the format will be provided during the Winter semester.


IV.    Course Policies

Policy on Missed Term Work

As flexibility for missed or late homework assignments has been built into the marking scheme, late and missed assignments will not be accepted for any reason.

Please note that Verification of Illness forms (also known as a “doctor’s note”) are temporarily not required. Students who are absent for any reason (e.g., COVID, cold, flu and other illness or injury, family situation) and who require consideration for missed academic work should report their absence through the online absence declaration. The declaration is available on ACORN under the Profile and Settings menu.

If you miss a term test or the final assessment, then you must inform your course Instructor within 72 hours of the test. No exceptions. If your request is approved, you may receive an accommodation in the form of a re-weighting of your assessments.


Email Policy

Should you have a question that is not answered on the course site (please check there first!) please note that all communications with the Course Instructor or TA’s must be sent from your official utoronto email address, with the course number included in the subject line. If these instructions are not followed, your email may not receive a response.


V.    Institutional Policies and Support

Academic Integrity

All suspected cases of academic dishonesty will be investigated following procedures outlined in the Code of Behaviour on Academic Matters (https://governingcouncil.utoronto.ca/secretariat/policies/code-behaviour-academic-matters-july-1-2019). If you have questions or concerns about what constitutes appropriate academic behaviour or appropriate research and citation methods, please reach out to your Course Instructor. Note that you are expected to seek out additional information on academic integrity from me or from other institutional resources (for example, the University of Toronto website on Academic Integrity http://academicintegrity.utoronto.ca/).


Copyright

This course, including your participation, will be recorded on video and will be available to students in the course for viewing remotely and after each session.

Course videos and materials belong to your instructor, the University, and/or other sources depending on the specific facts of each situation and are protected by copyright. Do not download, copy, or share any course or student materials or videos without the explicit permission of the instructor.

For questions about the recording and use of videos in which you appear, please contact your instructor.


Accessibility

The University provides academic accommodations for students with disabilities in accordance with the terms of the Ontario Human Rights Code. This occurs through a collaborative process that acknowledges a collective obligation to develop an accessible learning environment that both meets the needs of students and preserves the essential academic requirements of the University’s courses and programs.

Students with diverse learning styles and needs are welcome in this course. If you have a disability that may require accommodations, please feel free to approach your Course Instructor and/or the Accessibility Services office as soon as possible. The sooner you let us know your needs the quicker we can assist you in achieving your learning goals in this course.


Link to Accessibility Services website: https://studentlife.utoronto.ca/department/accessibility-services/


Equity, Diversity and Inclusion

The University of Toronto is committed to equity, human rights and respect for diversity. All members of the learning environment in this course should strive to create an atmosphere of mutual respect where all members of our community can express themselves, engage with each other, and respect one another’s differences. U of T does not condone discrimination or harassment against any persons or communities.

Services and Support


Other Academic and Personal Supports

• Writing Centre https://writing.utoronto.ca/writing-centres/arts-and-science/

• U of T Libraries https://onesearch.library.utoronto.ca/

• Feeling Distressed? https://studentlife.utoronto.ca/task/support-when-you-feel-distressed/

• Academic Success Centre https://studentlife.utoronto.ca/department/academic-success/

• College/Faculty Registrars https://future.utoronto.ca/current-students/registrars/


VI.    Schedule of Lectures

Here is a tentative weekly schedule of topics.
Week 1
          Chapter 1: 1.1 -1.3, Appendix A
          Introduction, primes, Fibonacci numbers, induction
          gcd’s and lcm’s, Euclidean algorithm
          linear Diophantine equations

Week 2 HW1 due
          Chapter 2: 2.1-2.2
          Prime factorization, p=4k+3, twin primes

          Zeckendorf’s theorem

Week 3 HW2 due
          Chapter 2: 2.3-2.4
          prime number theorem, Fermat and Mersenne primes
          Primality testing and factorization

Week 4 HW3 due
          Chapter 3: 3.1-3.4
          Congruences, [a]_n
          Linear congruences, Chinese remainder theorem

Week 5 HW4 due
          Midterm 1
          Chapter 3: 3.4, Chapter 4: 4.1
          Fermat’s little theorem, non-linear congruences
Reading Week

Week 6 HW5 due
          Chapter 4: 4.2Primality testing, pseudo-primes base 2, pseudo-primes base a,
          Carmichael numbers, Miller’s test

Week 7 HW6 due
          Chapter 4: 4.3, Chapter 5: 5.1-5.2
          Congruences modulo prime powers, Euler’s phi-function

Week 8 HW7 due
          Chapter 6: 6.1-6.4, Appendix B
          Units, primitive roots

Week 9 HW8 due
          Chapter 5: 5.3, Chapter 6: 6.5 and 6.7
          RSA and cryptography

Week 10 HW9 due
          Midterm2
          Chapter 7: 7.2-7.4
          Quadratic reciprocity, Legendre symbol

Week 11
          Selected topics, as time permits
          Fermat’s last theorem, abc conjecture

Week 12 HW10 due
          Selected topics, as time permits
          Transcendental numbers, Liouville numbers
          review