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Supersymmetric lattice models: Field theory correspondence, integrability, defects anddegeneracies

Fokkema, T.B.

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Citation for published version (APA):Fokkema, T. B. (2016). Supersymmetric lattice models: Field theory correspondence, integrability, defects anddegeneracies.

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Download date: 19 May 2020

Acknowledgements

I would like to thank the people that have been important to me along the roadto this thesis. Thinking back to the years that have past I will mention themchronologically. First I would like to thank Jean-Sebastien Caux, who hired meas a PhD student in september 2011. J.-S. thanks for your confidence in meand giving me the freedom to pursue my own interests. Our discussions ledtogether with Sebas Eliens to a publication which is not part of this thesis. Sebas,thanks a lot for the nice collaboration, we had many insightful discussions andwe learned a lot together. It took us some time to figure out the right questionsand answers and how to interpret the numerical results but it resulted in a verynice publication. At the same time I also learned a lot from discussions withJorn Mossel and Milosz Panfil on the GGE and form factors for the 1D bose gas,thank you for explaining and discussing so many things.

In the summer of 2013 I met Liza Huijse at the low-dimensional quantumcondensed matter workshop in Amsterdam and a few weeks later I joined aresearch project that Liza Huijse and Christian Hagendorf were working on. Thiswork led to our joined paper which is the subject of chapter 3 and 4 of this thesis.Liza, thanks a lot for the many Skype discussions and for making it possible tovisit you at the SITP in Stanford. You explain complex material very well, fromyou I learned about the supersymmetric lattice models that became the subjectof this thesis. You also taught me the basics of conformal field theory and sharedwith me your enthusiasm for these subjects. Christian, thanks for the many hourswe spend discussing, from you I learned very interesting aspects of the Betheansatz which became important in our paper. Thanks for your hospitality inLouvain-la-Neuve.

In the beginning of 2014 I was very interested in the Mk models and conformalfield theory and Kareljan Schoutens and I started to work on a project. Kareljanthen became my PhD supervisor. Kareljan, thanks a lot for suggesting veryinteresting research projects. It has been a great pleasure to work with you. Ourcollaboration went very well and the rest of this thesis (chapters 5, 6 and 7) isbased on our joint results. Kareljan, I am very glad that I have been able to learnso much from you. I also learned a lot from your perseverance and creativity.Many times our discussions lead directly to new ideas and insights which we couldbuilt further on. You have been a great supervisor! Thanks also for carefullyreading the manuscript of this thesis.

Besides the visits that I made to Stanford and Louvain-la-Neuve, I visitedFlorence and Oxford together with Kareljan. I would like to thank Fabian Esslerand Paul Fendley for their hospitality at the Rudolf Peierls Centre in Oxford andAndrea Cappelli for the hospitality at the INFN in Florence. The research in thisthesis also benefited from discussions with Paul Fendley, Ville Lahtenin, JasperStokman, Philippe Corboz and Bernard Nienhuis.

During my PhD I have attended a number of PhD schools. I always enjoyedthese schools a lot because of the opportunity to learn so many new things and

Acknowledgements

meet new people. I would like to thank Rembert Duine and Vincenzo Vitelli forthe organization of the DRSTP PhD schools. Two other schools where I havelearned a lot where the 2014 and 2015 editions of the Lectures on StatisticalField theories at the Galileo Galilei Institute for Theoretical Physics in Florence.Thanks to Andrea Cappelli, Filippo Colomo, Giuseppe Mussardo, Denis Bernardand Gesualdo Delfino for the organization!

I would like to thank my o�ce mates Sebas and Jacopo for the four pleasantyears together in the o�ce. And I would like to thank my other colleagues at theInstitute for Theoretical Physics of the UvA. Especially Bram, Rianne, Rogier,Shanna, Moos, Gyorgy, Ville, Enej, Omar, Davide and Michael. During my PhDI was a teaching assistant for four courses, I would like to thank Bernard Nienhuis,Ari Turner and Theo Nieuwenhuizen for the pleasant collaboration. I wouldalso like to acknowledge the supporting sta↵ of the IoP at the UvA, Yocklang,Anne-Marieke, Natalie, Fatima, Rita and Joost.

Vivian, it has been great to share with you the experiences along the pathtowards a PhD after our master studies in Utrecht. It was nice to share aroom with you at our common schools and conferences. I have been lucky thatthree other good friends, that moved abroad to pursue their PhDs, happenedto live in places that I visited for research. Renee and Thomas, thanks for thegood company during the times I was in Oxford and for letting me stay in yourapartment. Sander, it was great to be able to catch up during my visit to Stanfordand I hope to be able to meet more often again in the future.

Finally, I would like to thank Douwe, Maaike, Marieke, Eveline and Olof forthe support, company and the shared adventures.

187

Contributions to publicationsI would like to emphasise that the published works have been obtained in collab-oration with co-authors. Many hours of discussions and skype sessions have leadto these results. My main contributions to the publications have been

• [1] Relation of the dynamical supersymmetry Q� with Bethe ansatz. Ana-lytical and numerical checks on the action of the dynamical supercharges.Minor contributions to other parts of the article.

• [2] Contributed to all parts of the article and performed all the numericalcomputations.

• [3] Contributed to all parts of the article. Developed algorithm to automatizethe CFT calculations using Mathematica and used this for example to findthe exact two spinon eigenstates of H

2

. Also developed an algorithm whichmade it possible to find the rules which give the spin-content of spin-fullmulti-spinon states.

• [4] Contributed to all parts of this paper.

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