Tjark Sievers

Hi, I'm Tjark. I study physics and do stuff with computers.

Mar 6, 2024 | Project Showcases


Docker | Flask | Python | TailwindCSS |

During my time working at the PHYSnet data centre, I developed a web application based on Flask to interface with a database containing data about devices we managed. Some Tasks using this database were giving out PCs, Laptops and monitors to research groups, handling taking these devices back and filling out everything needed by the university management when the devices are coming in. I managed to simplify many steps, for example automatically filling out the fields for hostnames with a specified naming scheme based on what hostnames are already given out or providing a simple interface to match inventory numbers given by the university management to the serial numbers of devices that were freshly delivered and then writing it into the database.

Feb 9, 2024 | Blog

Week 17 // 29.01. - 09.02.

in Study Blog

Its time for a another review of my time spent last semester! I had semester with some quite small units, mostly preparing talks or things with just a single lecture peer week. The module “Anthropogenic accidents” had a super long lecture, so I can understand the most time going into it. And all in all, its just half of the time I used for full lectures in the last semesters.

Feb 2, 2024 | Blog

Week 16 // 29.01. - 02.02.

in Study Blog

This was the last week of the semester, and with that the last semester of me having lectures at all. Everything that is left now is my master thesis. I’m starting that in April, next week I meet up with my supervisors to talk about the topic and see what I can do in preparation.

Jan 26, 2024 | Blog

Week 15 // 22.01. - 26.01.

in Study Blog

This week I got sick again… I sadly had to cancel my talk because of that, its a bit sad all the preparation was for nothing now, but I still learned a lot during it, so its all fine. Also I’m not dependent on the credits, so I could just tell the professor we dont need to find another date in the semester break to repeat it. But I played a lot of Stardew Valley while sick and also read a lot, that was super nice!

Jan 19, 2024 | Blog

Week 14 // 15.01. - 19.01.

in Study Blog

I held the second of three presentations for this semester, and it went super well! The topic was superconductivity in a bit more advanced way, my supervisor and I chose the topic because it will fit very neatly into my master project I’m starting this summer. The next two weeks will be about finishing up my last presentation and all the things from my other modules and then enjoy two months of pretty much nothing going on!

Jan 12, 2024 | Blog

Week 13 // 08.01. - 12.01.

in Study Blog

It was so so cold here last week. I was back in Uni and at work after the winter holidays and need to now finish up the last things for the two talks I still need to do. It wont be super stressful over January, but I’m still looking forward to February and having basically nothing going on before I start my master’s thesis.

Jan 7, 2024 | Project Showcases


DaisyUI | Hugo | TailwindCSS |


A clean Hugo theme with yellows and greens using TailwindCSS and DaisyUI components.

Jan 5, 2024 | Blog

Week 12 // 01.01. - 05.01.

in Study Blog

I really enjoyed the christmas break, I basically did nothing uni-related over the whole last 2 weeks. This weekend I’m starting to ramp up the work on my talks again, working through a lot of interesting physics (I get so much about superconductivity here!).

Dec 22, 2023 | Blog

Week 10 // 18.12. - 22.12.

in Study Blog

I had the first of my group seminar talks on Tuesday! It went super well, I really got amazing feedback. The talk was about a super interesting paper from July, a group at Harvard managed to design an experiment that produced anyons (those are particles that are neither fermions and bosons) with a freely adjustable statistical angle. I mostly went into the theory behind it (a paper from 2011 which is amazingly simple) and then some experimental results.

Dec 15, 2023 | Blog

Week 9 // 11.12. - 15.12.

in Study Blog

This week was all about preparing my presentations for the group seminar talks. It’s a lot of fun, really digging into some current papers, the science behind them and then trying to make a story out of that.

Dec 8, 2023 | Blog

Week 8 // 04.12. - 08.12.

in Study Blog

This week I was sick with Covid… In the beginning of the week it was quite bad, so I did not get around to do anything, but later in the week I already felt quite fine again, so I got to work through some content from Colemans book on superconductivity for one of my seminar talks.

Dec 1, 2023 | Blog

Week 7 // 27.11. - 01.12.

in Study Blog

I tried a new café on Tuesday. It is right next to the physics university campus and it serves some really nice coffee, so I will probably be there more often and do some work there.

Nov 24, 2023 | Blog

Week 6 // 20.11. - 24.11.

in Study Blog

This week I worked through more theory for the talks in the group seminars I’m attending. The one on Dec 6th is already coming very close, but I’m slowly getting a grip of Mott insulators. Also I spent a lot of time working on a project for work. Its a website for distributing hardware to the research groups and I just got a lot into polishing the UI, using tailwindcss. Its a lot of fun, just seeing how I can make things look nice and uniform across the website.

Nov 17, 2023 | Blog

Week 5 // 13.11. - 17.11.

in Study Blog

Last Sunday I played a big board game. Like, a BIG one - 12 straight hours of Twilight Imperium 4 with the Prophecy of Kings expansion. It was a lot of fun, and I’m very down to playing again with the group some time. Also all my talk preparations ramp up, and it’s really satisfying to see how the pieces click together and that apparently I know quite a bit in correlated electron physics by now.

Nov 14, 2023 | Blog

Hopes and Expectations

in Master Thesis in Sweden

Erasmus |

Currently, I am picking up the first materials to work into the theory of what my thesis will be about. As I am doing that, I am thinking about what I hope to get out of the work on my thesis. It might be a good idea to write down these hopes and expectations, check in again at a later time and see what turns out true. Research with results In my bachelor’s thesis I worked with a software package that is used the research group to produce a lot of interesting results, but I myself did not get to a point where I produced data I could analyse and say what happens there, even with the input data already provided by the group.

Nov 10, 2023 | Blog

Week 4 // 06.11. - 10.11.

in Study Blog

This Wednesday I went to a symposium on occasion of the Hamburger Prize for theoretical physics, which was awarded to Edward Witten this year. The talks went way over my head for the most part, as they focused on string theory and mathematical physics in general. I also went to the award ceremony, which was a lot of fun! Also I noticed I probably need to get a suit, I was very lost on what to wear for it.

Oct 20, 2023 | Blog

Week 1 // 16.10. - 20.10.

in Study Blog

This semester is the last one before my master thesis, and all I gotta do are some credits in elective courses. I chose a lecture about anthropogenic accidents and one about working with data. I also have some presentations in group seminars, I thought this might be a good use of my time, just really getting into some specific topics and practicing my presentation skills a bit.

Oct 19, 2023 | Blog


in nolopot - A Computational Physics Project

Python |

This is the first post in a series of blog posts is about nolopot, a software package that started in a physics lecture I attended in 2022. Currently it can be found on Gitlab. It was a project I did together with another person in the course, and after the course finished I took the code we had so far and build the current infrastructure of testing and deployment around it.

Oct 8, 2023 | Blog

Finding a Project and Applying for Erasmus Funding

in Master Thesis in Sweden

Erasmus |

Next year, I will spend 4 months in Sweden for the research phase of my master’s thesis. This post goes over some organisational details, the process of getting support at my home university in Hamburg, getting the funding for it via Eramus and finding a research group and project.

Oct 1, 2023 | Project Showcases


Computational Physics | Python |


Python package to calculate bound states and (someday) scattering for non-local potentials. Mostly a testing ground for workflows, packages, tools and coding practices.

Sep 13, 2023 | Blog

Time tracking review

in Study Blog

It’s now quite a lot after the end of the semester and all my exams, I thought I might do another review of how I spent my time studying this semester. First of all, just the time in the semester: So I worked about equally in all modules. Interestingly, the module where I spent the most time was one where we just had one lecture per week. So I noticed here that interest decides so much what I spend my time on, on a week-to-week basis, and that things will fill the time I give to them.

Jul 7, 2023 | Blog

Week 14 // 03.07. - 07.07.

in Study Blog

This week I worked a lot, mostly on pushing forward my backlog of older lectures I didnt yet work through, in preparation for the upcoming exams. I did make some progress, but I also didnt quite prioritise resting as much as I wanted, so I worked quite a few evenings and it was a bit draining all in all. But we finally got around to doing a board game night on Friday, that was a lot of fun!

Jun 23, 2023 | Blog

Week 12 // 19.06. - 23.06.

in Study Blog

I was still on vacation in the beginning of the week, so I didn’t do a lot beyond a watching the lectures on Monday and preparing the exercise sheet for topology. I somehow really got myself into stress about exams now, that dominated the last few days a bit. They are still a bit away, but still, getting stressed about preparation there.

Jun 23, 2023 | Blog

Week 13 // 26.06. - 30.06.

in Study Blog

A typical symptom of me getting really unhealthily stressed out about uni work are a lot of logged time entries in the evening, and mostly short ones. This means I don’t try go get rest in the evenings, but always try to push myself further. And last week that was definitely the case. For next week I want to commit to using my evenings to rest, and use my days a bit better, just to get out of this mindset that I could always do more.

Jun 16, 2023 | Blog

Week 11 // 12.06. - 16.06.

in Study Blog

This week I took Tuesday completely off to spend time with my family. Regardless I managed to get through every lecture and a good part of my assigned exercise sheets. Not a lot more happened this week, except that I sat outside for watching a lecture from my backlog, hopefully I can do that more often!

Jun 9, 2023 | Blog

Week 10 // 05.06. - 09.06.

in Study Blog

Currently there is a lot to do at my workplace, because all the deliveries of new devices are coming in, so I need to put them all into inventory, which took up a lot of time. Because of that, I still feel behind on study materials for the exams, but I still can follow the content of all lectures and also still at least some of my exercise sheets, so its mostly a thing of “if I did those things I would have a more chill time before the exams” and not a “I’m absolutely not following this at the moment” like it was last semester at some times.

Jun 2, 2023 | Blog

Week 9 // 29.05. - 02.06.

in Study Blog

This week wasn’t that exceptional, I am kind of slacking in many aspects right now, but I can still follow most of the contents of my lectures. What I really need to get on with is preparing study sets for all my lectures. They are the foundation for my exam preparation and I’m quite behind right now. As such I wanted to show a bit how I use Goodnotes study sets.

May 28, 2023 | Project Showcases

Docker |


This website and its deployment process are available publicly on Gitlab. Deployment is done via Gitlab CI, using Docker containers to separate the different services running on the server. All the pages can be found under pages in respective directories. Each page has its own docker-compose.yml file, these are added in the .gitlab-ci.yml to be deployed. All pages get deployed on every commit to main. Current pages under the domain:

May 26, 2023 | Blog

Week 8 // 22.05. - 26.05.

in Study Blog

This week I mostly did work on the exercises in Quantum Technologies outside of visiting my usual lectures. Except for that I didn’t do a lot of work on lectures, so my backlog on lectures grew a bit. I need to start working on that, so that I have some study material already in place. I’m using Goodnotes study sets for the first time this semester, it’s very nice to be able to directly create index cards from my notes.

May 23, 2023 | Project Showcases


Hugo |


A Hugo theme forked from HugoTeX, strongly tailored to my requirements.

May 19, 2023 | Blog

Week 7 // 15.05. - 19.05.

in Study Blog

I got a lot of stuff done last week, im surprisingly up to date on all of my lectures, and also got through the most important exercises for the week, which is pretty nice all around. But furthermore, I still got to spend a lot of time with my girlfriend, who visited me. We had a lot of study dates over the week, but were also able to do some fun stuff, and it makes me so happy that on the one hand the workload this semester is way more chill and on the other hand that I have way more self awareness about how I learn best and what I need to do to follow my lectures.

May 12, 2023 | Blog

Week 6 // 8.05. - 12.05.

in Study Blog

Last week was a bit all over the place, just had little time frames to work on exercises and lectures, but that was quite fine, because the next week is a holiday week at our university, so I have a bit more time to finish all exercises then. I missed my two quantum computer lectures, one because my bus was super late and the second one because there was a introductory tutorial about polarisation given by the last winner of the Hamburger prize for theoretical physics, Nicola Spaldin.

May 5, 2023 | Blog

Week 5 // 1.05. - 5.05.

in Study Blog

I slacked a bit on an assignment I have for next Monday, so a bit of last minute work needed to go into that sadly. Otherwise I’m pretty up to date working on the Quantum Computing lecture, as well as on the Topology lecture (which is pretty exciting, last semester I was full on packed with just the exercises and couldn’t even work on lecture revision). Next week is another normal week of lectures, after that we have a week of vacation, so I’m gonna try to get all of the time sensitive stuff done next week, so I can have the free week as free as possible.

Apr 28, 2023 | Blog

Week 4 // 24.04. - 28.04.

in Study Blog

This week I really noticed how much more chill my week is compared to last semester. I didn’t sleep that well most nights, so wasn’t as motivated most days, and still stayed on top of almost all lectures and exercise sheets. Much of that is just learning from last semester how much time I really have and what helps me most studying for things and what is just unnecessary work. Once I have my workflow figured out for all lectures, I’m gonna share my process in more detail.

Apr 21, 2023 | Blog

Week 3 // 17.04. - 21.04.

in Study Blog

This week was the first Uni week in a normal routine. And it’s really a good routine, with a some more stressful days and also rest days in between. Mondays I have two lectures (Quantum Computing and Quantum Technologies 2) and one exercise class, the first one starting 10, with loads of time in between to work on exercises. Tuesdays I actually have no lectures, so I use the time to sleep in a bit, sit in the library and work on exercise sheets.

Apr 14, 2023 | Blog

Week 2 // 10.04. - 14.04.

in Study Blog

Unfortunately I caught a mean cold at the new years party I attended, so I spent the last few days sick in bed. Still did a bit of Uni work, submitted two exercises for the Computational physics class and worked through some exercise problems and lectures for the quantum field theory class. All in all quite satisfied with everything I was able to do despite the circumstances. Also thankful to have some (forced) resting time, as the whole of January will be quite stressful.

Feb 3, 2023 | Blog

Week 16 // 30.01. - 03.02.

in Study Blog

During this semester I tracked all my time I spent either studying or working at my job at the our physics departments data centre (additionally there is a category for study breaks, which encompasses breaks in pomodoro cycles). The Computational physics lecture was by far the most time consuming, as I tried to solve the exercise every week and I needed to finish everything during the semester for the final grade.

Jan 27, 2023 | Blog

Week 15 // 23.01. - 27.01.

in Study Blog

This was now the second to last week of the semester, so all lectures are slowly coming to a close. Its quite satisfying to have many strings coming together in those final topics, thats what theoretical physics is all about for me, building up a system of tools and then seeing how they operate together to formulate and solve physical problems. Next week the final project presentation for the Computational Physics class, which is a significant part of the final grade.

Jan 20, 2023 | Blog

Week 14 // 16.01. - 20.01. //

in Study Blog

The start of this week was very stressful, as I needed to finish a quite intense exercise sheet for the QFT in correlated many-particle systems until Thursday, which additionally got roadblocked because we finished most of the topics we needed on Wednesday, so there effectively was only one day to do all of that. I also ran the slides of the project presentation for the Computational Physics by our lecturer, and she was quite pleased with it already.

Jan 13, 2023 | Blog

Week 13 // 09.01. - 13.01.

in Study Blog

The end of the semester is rapidly coming closer. I’m wrapping up the Computational Physics class with the last exercises and the final plots I need for the project presentation. The QFT in correlated many-particle systems course will be finished with an oral exam, I’m not really worried about that as I already went through most of the course work in another course last semester. So the only written exam will be Quantum Field Theory, which I will take near the end of march.

Jan 6, 2023 | Blog

Week 12 // 02.01. - 06.01.

in Study Blog

Unfortunately I caught a mean cold at the new years party I attended, so I spent the last few days sick in bed. Still did a bit of Uni work, submitted two exercises for the Computational physics class and worked through some exercise problems and lectures for the quantum field theory class. All in all quite satisfied with everything I was able to do despite the circumstances. Also thankful to have some (forced) resting time, as the whole of January will be quite stressful.

Dec 23, 2022 | Blog

Week 10 // 19.12. - 23.12.

in Study Blog

This week I once again worked a lot on the Computational Physics exercises. I made good progress on them, now I have to do debugging on some of them, but I will definitely finish all the outstanding exercises over Christmas break. Another goal for the Christmas break is to get on with the parts of Quantum Field Theory I didnt get yet (it’s mostly the part dealing with perturbation theory and the basics of Spin 1/2 fields), as that will probably be the important for getting the rest of the lecture (as well as being important for the exam).

Dec 23, 2022 | Blog

Week 11 // 26.12. - 30.12.

in Study Blog

I had a good few days with my family over christmas, still did a little bit of uni work, because I always get a bit uneasy when I have this stark contrast of going from a super high stress situation to doing nothing. Was mostly working through some old lectures. All in all I would say I’m pretty good on course for the things I want to finish during the Christmas break, will evaluate that next week.

Dec 16, 2022 | Blog

Week 9 // 12.12. - 16.12.

in Study Blog

This week I wasn’t really at uni much. Monday I was still away for a trip with some friends visiting the childhood home of one of them, mostly for seeing the Christmas market there, Thursday I was at a concert and drove over visiting some other friends on Friday. Additionally one of my professors had covid, tested negative on a rapid test, still had symptoms and decided that was enough to go to uni, so I decided to just skip that lecture to avoid getting infected that way right before Christmas.

Dec 9, 2022 | Blog

Week 8 // 5.12. - 9.12.

in Study Blog

I’m noticing how much I am in need of a break in the semester, to catch up on some assignments and content as well as just having some time for time where I don’t need to get up super early every day. So very happy that I only have two weeks left until winter break. This week got very stressful in the end, with the next exercise sheet for QFT in correlated many-particle systems which got uploaded Thursday and is due Wednesday next week.

Dec 2, 2022 | Blog

Week 7 // 28.11. - 2.12.

in Study Blog

It’s getting very christmassy around here. Discovered I will be starting my days with a cute slogan due to my advent calendar. I am a bit behind on one exercise in my Computational Physics class, I have some weird bugs there and I just cant seem to get my program to converge to the right values. At the moment I ignore that a bit and work on the next assignment, because the exercises will be collected at the end of the semester, so I can just work on the next ones for now and use the christmas holidays to work on that one a bit.

Nov 25, 2022 | Blog

Week 6 // 21.11. - 25.11.

in Study Blog

It’s suddenly getting very cold here, so im packing myself into layers of warm clothes. This also means Christmas markets are opening, so I already strolled a bit, getting into the mood. All the lights are really a great part of winter here! The two lectures about Quantum Field Theory (one in the context of high energy physics, one in the context of condensed matter physics) have so many similarities in terms of what the strategies are dealing with interactions in the respective theories.

Nov 18, 2022 | Blog

Week 5 // 14.11. - 18.11.

in Study Blog

Looking back, I did a lot of coding this week, which me very happy. Im making good progress on the project for the computational physics class (will go into more detail into what exactly I’m doing once I have some results to show). This also means I neglected my other classes a bit, so I need to work on that today for a bit, especially the Quantum Field Theory exercise sheet, did not start anything on there yet.

Nov 11, 2022 | Blog

Week 4 // 7.11. - 11.11.

in Study Blog

I was quite happy with myself this week. Got back into preparing oatmeal two times a week, which gives me a something to eat in the morning as well as the afternoon and makes me feel so much better compared to going hungry or buying snacks somewhere on campus. I had to make my first project report for the Computational Physics class, the professor was pretty happy with that! My next task there is to understand numeric integration via Gaussian quadrature, I still need to do that this weekend.

Nov 4, 2022 | Blog

Week 3 // 31.10. - 04.11.

in Study Blog

I saw Cavetown this week! I noticed how much I already am back in a rhythm that works for me, because last weeks there were some points that broke that routine and consequently threw me out of some good habits I picked up before (like, I had to leave earlier one day, so I didn’t prepare my overnight oats, but then because of that I didn’t have them for the next day where I would have needed them).

Oct 28, 2022 | Blog

Week 2 // 24.10. - 28.10.

in Study Blog

Second week was a bit more chaotic than the last one, but I’m slowly finding a rhythm that works well for this semester. I have to do quite a bit of work this weekend, because I had some other stuff going on on Thursday and Friday, but it was wholly worth it! Next week the term projects for the computational physics will be distributed. That is definitely the course I expect to get the most practical experience out of, so I’m looking forward to getting an interesting project to work on during the semester.

Oct 21, 2022 | Blog

Week 1 // 17.10. - 21.10.

in Study Blog

Got back into things pretty well, I would say. This is my first (proper) semester in graduate studies, so there are some changes I need to get used to: smaller lectures, English as the main course language (which is not my mother tongue), way more independent choice of courses, just to name a few. I’m very happy to see my friend group from my undergraduate studies again and suffer through exercise sheets with them.

Jul 2, 2022 | Project Showcases

Bachelor Thesis

Computational Physics | DFT | Thesis |


In summary, my bachelor project was about a software package used in the research group and how to best run it on our local compute cluster. When I started my bachelor project, the group of Professor Wehling was starting pretty fresh at the university. The project we ended up on was to look at Quantum Espresso, evaluating how it runs best on our local compute cluster Quantum Espresso is a software package implementing Density Functional Theory (DFT), which is a very successful method to calculate electronic properties of materials.