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Effective Field Theory


About this course on Effective Field Theory

The course described below will start September 16, 2014.

8.EFTx is an online version of MIT's graduate Effective Field Theory course. The course follows the MIT on-campus class 8.851 as it was given by Professor Iain Stewart in the Fall of 2013, and includes his video lectures, resource material on various effective theories, and a series of problems to facilitate learning the material. Anyone can register for the online version of the course, and students at MIT or Harvard can also register for 8.S851 for course credit.

Effective field theory (EFT) provides a fundamental framework to describe physical systems with quantum field theory. In this course you will learn both how to construct EFTs and how to apply them in a variety of situations. We will cover the majority of the common tools that are used by different effective field theories. In particular: identifying degrees of freedom and symmetries, formulating power counting expansions (both dimensional and non-dimenstional), field redefinitions, bottom-up and top-down effective theories, fine-tuned effective theories, matching and Wilson coefficients, reparameterization invariance, and various examples of advanced renormalization group techniques. Examples of effective theories we will cover are the Standard Model as an effective field theory, integrating out the massive W, Z, Higgs, and top, chiral perturbation theory, non-relativistic effective field theories including those with a large scattering length, static sources and Heavy Quark Effective Theory (HQET), and a theory for collider physics, the Soft-Collinear Effective Theory (SCET).

Course Flow

Since this is an advanced graduate physics course, you will find that self motivation and interaction with others is essential to learning the material. The purpose of the online course is to set you up with a foundation, to teach you to speak the language of EFT, and to connect you with other students and researchers that are interested in learning or broadening their exposure to this subject. Each week you will complete automatically graded homework problems to test your understanding and to help you master the material. You are expected to discuss the homework with other people in the class, but your online responses must be done individually. To facilitate these interactions there will be a forum for student-to-student discussions, with threads to cover different topics, and moderators with experience in this field. Student learning and discussions will also be prompted by questions posed after each lecture topic.

There will be no tests or final exam, but at the end of the course each student will give a 30 minute presentation on an EFT topic of their choosing. The subject of effective field theory is rich and diverse, and far broader than we will be able to cover in a single course. The presentations will create an opportunity for you to learn about additional subjects beyond those in lecture from your fellow students. To facilitate this learning opportunity, each student will be required to watch and grade eight presentations from among their fellow students. Of these eight, you will view 5 presentations that will be chosen for you, and you will view at least 3 more that you choose yourself from among the available topics.

Since this is a graduate course we anticipate that learning the subject, and having the 8.EFTx materials available as an online resource will be more valuable to most of you than obtaining a grade. Therefore anyone who registers for the course will be able to retain access to the course materials after the course has ended. Since some of you may find a grade useful, we will compute a grade for everyone by using a combination of homework problems (50%) and your final research presentation project (50%). For many of the course elements you may work at your own pace. The presentation project will be due December 16th. For those following the suggested schedule there is a one-week break over the Christmas & New Years holiday, and two homework problems that are due in January.


In addressing the material in this course we will assume familiarity with Quantum Field Theory, at the level of Peskin & Schroeder or Srednicki, such as might be obtained from having taken a graduate course on this subject. In particular we will assume knowledge of abelian and nonabelian gauge theories, constructing Lagrangians, renormalization, dimensional regularization, and the calculation of observables like cross sections. At the start of the course a review will be provided for material on the renormalization group and for material outlining the Standard Model of particle and nuclear physics as a quantum field theory.

MIT students are expected to spend 12 hours per week on 8.EFTx, and if you have the necessary background knowledge, we estimate that it will also take you 12 hours per week to do well.

Course staff

Iain Stewart

Professor Stewart is a Professor of Physics in the Physics Department of MIT. He got his PhD in Theoretical Physics at Caltech in 1999, and joined the Physics faculty at MIT in 2003. Beyond creating this graduate course on Effective Field Theory, he has also taught a graduate class in Quantum Field Theory, and undergraduate classes in Advanced Classical Mechanics and Quantum Mechanics. His research specializes in designing and using Effective Field Theory to describe physics at collider experiments like the Large Hadron Collider, B-factories, fixed-target experiments, and e+e- colliders. He is a former Sloan Fellow, a Fellow of the Alexander von Humboldt Foundation, and was elected a Fellow of the American Physical Society in 2013.



Saif Rayyan

Saif Rayyan is a lecturer in the Physics Department and the Concourse Program at MIT. He received his Ph.D. in theoretical particle physics from Virginia Tech before switching his interests to teaching and to physics education research. He moved to MIT as a postdoc working with the RELATE group (Research in Learning, Assessing and Tutoring Effectively). Now, in addition to teaching introductory physics, Saif is working on the development of courses on edX, and trying to find the best practices in using online platforms to help students learn.


Daniel Kolodrubetz

Daniel Kolodrubetz earned his BSc in physics from Caltech in 2011. Since then, he has been a PhD candidate at MIT where he studies aspects of collider physics from an effective theory perspective.



Evangelos Sfakianakis

Evangelos Sfakianakis earned his Diploma in Electrical and Computer Engineering from the National Technical University of Athens in 2007 before coming to MIT to pursue a PhD in theoretical physics. As of Fall 2014 he will be a Fortner Postdoctoral Fellow at the University of Illinois at Urbana-Champaign. His research so far focuses on the early universe, ranging from inflationary perturbations to the formation and evolution of oscillons.


Frequently Asked Questions

What do I have to buy in order to participate in the course?

Nothing. All edX courses are free. The lectures, homework, and lecture notes are all available online.

Will certificates be awarded?

Yes. Online learners who achieve a passing grade in 8.EFTx will earn for free a certificate of mastery. These certificates will indicate you have successfully completed the course, but will not include a specific grade. Certificates will be issued by edX under the name of MITx.

What textbook do I need for the course?

In 8.EFTx readings will be mainly from a latex version of the lecture notes and freely available online arXiv research articles. Occasionally additional reading from commonly available quantum field theory textbooks will be suggested to supplement these free sources.

When can I watch the lectures?

You can watch the lectures any time at your leisure.

Can I register to the class after the start date has passed?

Yes, you can register at any time between the start date and the end date. To obtain the certificate, however, you will have to get at least 60% of the total available points for the class.

I don't have the prerequisites. Can I still take the course?

We do not check students for prerequisites, so you are certainly allowed to try. However, 8.EFTx does depend on previous experience with algebra and trigonometry and with some calculus. If you do not know these subjects before taking the class, you will have to learn them over the semester.

Other questions

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If you have any questions about 8.EFTx that are not answered in this FAQ, please ask them in the discussion forum.

  1. Course Number

  2. Classes Start

  3. Classes End

  4. Estimated Effort

    12 hours per week
  5. Requirements

    A graduate course on Quantum Field Theory.