Beskjeder
Dear all, this is our last week of lectures and the plan is to
Thursday:
Repetition from last week and wrapping up discussion of the CCD approach
Introducing a diagrammatic approach
How to write your own coupled-cluster theory code, pairing model example (follow-up from second midterm)
Coupled cluster theory, singles and doubles excitations, diagrammatic expansion
Friday:
Coupled cluster theory for singles and doubles excitations using a diagrammatic derivation
Summary of course and discussion of final oral exam
Lecture material: Lecture notes and Shavitt and Bartlett chapters 9 and 10. See also slides at?https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/pub/week48/pdf/cc.pdf and this week's slides at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/pub/week48/ipynb/week48.ipynb
Best wishes to you all,
Morten
Dear all, here are our plans for week 47, November 17-21
Thursday:
a. Derivation of coupled cluster equations for doubles only
Friday:
a. Derivation of doubles excitation equation with diagrammatic expansion
b. Applications to the pairing model from the second midterm
c. Discussion and work on the second midterm
Lecture material: Lecture notes (these notes at https://github.com/ManyBodyPhysics/FYS4480/tree/master/doc/pub/week47) and chapter 9 of Shavitt and Bartlett, in particular sections 9-1-9.3
Best wishes to you all and good luck with the second midterm
Morten
First midterm, with deadline October 20
Here's the first midterm, we will discuss it during the exercise sessions and partly during the lectures on Friday October 10.
The link is at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/FirstMidterm2025.pdf
Best wishes.
Dear all, we hope this week started the best possible for all of you.
Here are some updates for this week (week 35). On Thursday we plan to finalize the calculations of expectation values for fermionic systems. Parts of this material is covered by the lectures from last week, see for example the slides from last week at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/pub/week34/pdf/week34.pdf (from with Ground state energy as header).
Thereafter (Friday most likely), we move into our first encounter of second quantization. The material is covered by this week's slides at for example https://manybodyphysics.github.io/FYS4480/doc/pub/week35/html/week35-bs.html or as a pdf file at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/pub/week35/pdf/week35.pdf
Our second exercise set, to be discussed on Friday is available at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/ExercisesWeek35.pdf...
Dear all, welcome back to FYS4480/9480.
This week we aim at discussing the following topics:
-Thursday: Second quantization, operators in second quantization and diagrammatic representation. Discussion of Wick's theorem
-Friday: Second quantization and Wick's theorem
Lecture Material and reading suggestions: slides from https://manybodyphysics.github.io/FYS4480/doc/pub/week36/pdf/week36.pdf, handwritten notes and Szabo and Ostlund sections 2.3 and 2.4. The material on Wick's theorem is covered by the whiteboard notes to be discussed on Thursday and Friday.
The third exercise set is at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/ExercisesWeek36.pdf
The solution to the exercises from week 35 are at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exe...
Dear all, welcome back to FYS4480/9480.
This week we will use the lecture on Thursday to summarize our discussions on Wick's theorem, with examples and discussions of the exercise set this week. We will also introduce a new reference vacuum state and the so-called particle-hole formalism, widely used in condensed matter physics, materials science, quantum chemistry and nuclear physics. This topic continues on Friday.
For Wick's theorem, chapters 3 and 4 of Shavitt and Bartlett is an ok read. idem for the particle-hole formalism.
Lecture Material: slides from https://manybodyphysics.github.io/FYS4480/doc/pub/week37/pdf/week37.pdf.
Fourth exercise set at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/ExercisesWeek37.pdf
The solution to the exercises from week 36 are at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/AnswersWeek36.pdf
Best wishes to you all,
Morten
Dear all, welcome back to FYS4480/9480. First, please excuse me for sending this mail late, I simply forgot to send yesterday.
I have also made some changes to the schedule from last week. I decided that instead of making a video of the particle-hole formalism, I opted for a regular lecture today instead. Also, I have posted (see link below) solution to the exercises from last week. They contain also a discussion of the parts of the exercises this week (exercise 1). Exercise 2 will be discussed during the lectures today and tomorrow.
The plan this week is thus to
Thursday: Discussion of particle-hole formalism with examples and diagrammatic representation.
Friday: Full configuration interaction theory
Lecture Material: These slides and chapters 3 and 4 of Shavitt and Bartlett covers most of the material discussed this week.
Fifth exercise set at https://github.com/ManyBodyPhysics/FYS...
Dear all and welcome back to a new week with FYS4480/9480. The plans this week are
Thursday:
Discussion of Full configuration interaction (FCI) theoryDiagrammatic representation of FCILipkin model as an example of applications of FCI theory&nbs...
Dear all, welcome back to FYS4480/9480.
This week, and the two coming ones, we will spend time on mean-field theories, starting with Hartree-Fock theory and then moving to density functional theory. The plan this week is to
Topics to be covered
Thursday:
a. Deriving the Hartree-Fock equations
b. Efficient ways of implementing the Hartree-Fock algorithm
Friday:
a. Stability of Hartree-Fock equations and Thouless' theorem
Lecture Material: These slides attached here and Szabo and Ostlund, sections 3.1-3.4
Seventh exercise set at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/ExercisesWeek40.pdf
Best wishes to you all,
Morten
Dear all, welcome back to FYS4480/9480. This week we plan to
Thursday:
Stability of Hartree-Fock theory, wrapping up discussions from lecture October 3, see slides from last week
The homogeneous electron gas in three dimensions
-Hartree-Fock solution and ground state energy
Friday:
Calculating the ground state energy of the electron gas
Discussion of first midterm
Lecture Material: These slides (see the attached pdf-file) and handwritten notes
First midterm set at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/FirstMidterm2...
Dear all, welcome back to FYS4480/9480.
The plans this week are to first finalize our discussions of the homogeneous electron gas in three dimensions by calculating the Hartree-Fock ground state energy. After this long detour we will get an expression for the energy which is a function of the density of the system. This serves as one of the starting points for density functional theory (which we discuss later today and partly tomorrow) and is known as the local density approximation.
Some of the derivation are not included in the slides for this week and will be presented during the lectures.
Else, we will use parts of Friday's lecture to discuss and work on the first midterm.
The plans are with, with link to the lecture notes https://github.com/ManyBodyPhysics/FYS4480/tree/master/doc/...
Dear all, first, a great thank you to everybody for heroic efforts with the first midterm. It has been a pleasure to read through them. Feedback is planned for the end of next week. Let me also now if it is ok if we schedule the second midterm for the first half of november, that is sometime during the week which starts with November 10, with a tentative deadline around November 17 (Monday) or 18 (or later that week). That way we avoid overlapping with the second project in FYS-STK and potential exams in other courses (some start around November 25). Each midterm counts 30% of the final grade.
Our last lecture with summary etc is planned to be November 28. We should also start planning the final oral exam (which counts 40% of the final grade). Since we are quite many, we will need two full days (45 mins per candidate). I know that FYS4170 has a scheduled exam on Dec 19. We could then opt for December 15 and 16, with the 15th reserved for th...
Dear all, we hope you are all doing well. The plan this week is
Thursday:
a. Time-independent perturbation theory
b. Examples of contributions to perturbation theory (whiteboard notes)
Friday:
a. Examples of contributions to perturbation theory (whiteboard notes)
Lecture Material: Shavitt and Bartlett chapter 4-6
Eight exercise set at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/ExercisesWeek44.pdf
Best wishes to you all,
Morten
Dear all, welcome back to FYS4480/9480. We hope this week has started the best possible way for you all.
This week we will continue our discussion of many-body perturbation theory and emphasize diagram rules and how to calculate higher contributions. In addition we will also discuss the so-called diagram theorem, which is a very important theorem for several many-body methods, such many-body perturbation theory, coupled cluster theory and Green's function theory. The plan this week is
Thursday:
a. Time-independent perturbation theory: examples of contributions in perturbation theory and diagrammatic representations
b. Diagram rules and their derivations
Friday:
a. Diagram examples
b. Linked diagram theorem
Note: Friday's lecture is a recording only, since I will be attending an all-day workshop, https://www.jus.uio.no/ifp/english/about/organization/nrccl/events/2025/xxxx-nordic-con...
Dear all, a warm welcome to everybody.
Our first lecture is Thursday August 21 at 1215pm in room F?257 in the Physics building. All lectures will be recorded and if you cannot attend physically, the zoom link is https://uio.zoom.us/my/mortenhj
All educational material pertinent to the course is at the GitHub
https://github.com/ManyBodyPhysics/FYS4480
and this week's material is at
https://github.com/ManyBodyPhysics/FYS4480/tree/master/doc/pub/week34
The first exercise set is at https://github.com/ManyBodyPhysics/FYS4480/blob/master/doc/Exercises/2025/ExercisesWeek34.pdf
We look much forward to meet you all, best wishes