Strings 2023 in Waterloo: A Week of Insight and Reflection

Since its foundation as a not-for-profit corporation devoted to theoretical physics, Perimeter Institute (PI) has organized several high-level activities. This institute has reached yet another milestone this year. For the first time in its history, PI had the honor of hosting an installment of Strings. This series of annual conferences brings together the entire string theory community and serves as a forum where we can update ourselves on the latest developments. Needless to say, it is the major conference in the field. As a first-time attendee, I was thrilled to be at the 33rd edition of this conference: Strings 2023.

After completing the registration and asking them to keep my suitcase, the very first activity at the beginning was breakfast (after a long and exhausting journey, there is nothing quite like the satisfaction of a well-deserved morning meal). Opening the conference, Robert Myers gave nice welcoming words and logistical remarks. Sabrina Pasterski subsequently took the floor, she was very glad to present Andrew Strominger, the first speaker of the morning. In a separate post, I will provide a summary of his talk, along with comments regarding the temperature of the boundary CFT3, and also shed light on a few other talks that I remember. Stay tuned! Anyway, if you are interested in the actual content of the talks, I suggest you have a look at the recordings here or view some of the slides here.

Participants shared time in well-organized leisure/social activities at the end of each day following the tradition in this annual conference. The game night took place on Monday and we had a selection of (board) games like Jenga, Dominion, Cards against humanity, etc. By the way, I didn’t know that Timber Tumble was another name for Jenga. I found the String Quiz prepared with the help of ChatGTP-4 exciting (and stressful at the same time). The game was hosted by Gaiotto. He brought four buzzers mimicking a typical fastest-finger game-show. Speaking of Gaiotto, it caught my attention that he was the only one who wore a facemask at the conference. The fastest team to buzz in by pressing their buzzer was allowed to give an answer, with negative points awarded for wrong answers. Some of the questions I can recall are: How many supersymmetries exist in 4D N=4 SYM?, What are baryons in string theory? What is the holographic dual of a Wilson loop?, What is the Cotton tensor? On Wednesday, we had an outstanding banquet dinner and the salmon I ordered was particularly tasty. We also enjoyed the memorial, moderated by Andrew Strominger, for Lars Brink, Stanley Deser, Jim Hartle, Valery Rubakov and Dennis Nemeschansky (stunning physicists who have recently passed) right there at Black Hole Bistro. Maldacena, using his cellphone, read the words about Lars Brink that had been prepared by (as far as I can remember) Michael Green who could not be there in person. During Witten's heartfelt speech, recounting stories and memories that celebrated the remarkable life of Stanley Deser, the weight of the occasion seemed to overwhelm him momentarily, causing him to pause. This pause served as a poignant moment, reminding everyone present that even powerful figures can be affected by the profound impact of loss. The memorial was followed by a graduation celebration for recently graduated, or expected to graduate in the next few months, PhDs. One of them was my friend Adolfo Holguin. The next day – on Thursday – we went to Waterloo Park East Field to play soccer. The other Thursday's recreational activity was going to Galaxy Cinemas at Conestoga Mall. As you may know, no recent movie has generated as much anticipation as Oppenheimer. So the organizers had the great idea of inviting us to see the movie. They provided us with transit passes (valid on all Grand River Transit and ION rapid transit light rail system) that we picked up at the registration desk. We did not need tickets, just showed up with our name badge to get into the theatre.

The organizers hosted a Town Hall on Thursday to discuss two topics: the formation and charges of a proposed Strings Planning Committee and a proposal to move the postdoc hiring deadline. This innovation is likely to be a feature of the installments of Strings to come as well. As David Gross said, some people have suspected the existence of some kind of cabal of old white men who run the Strings conference. That assertion is completely false. This series of conferences has been totally spontaneously driven by groups at institutes or universities who offered to host them. This initiative to raise the money and handle all the work is a good indicator of how healthy the community is. Certainly, given that there is no official organization that has any authority, it would not be a good sign if we had to go for a year or two without the Strings conference, or if we had two (competing) conferences in a single year dividing the community. Therefore, some of the seasoned members of the string theory community decided to organize an Ad Hoc Strings Planning committee. It currently consists of the following members: David Gross, Nathan Berkovits, Agnese Bissi, Stefan Fredenhagen, Igor Klebanov, Jeff Murugan, Rob Myers, Hirosi Ooguri, Eva Silverstein and Edward Witten, and you can find their proposal document here. Some participants were worried about the (lack of) geographical diversity of the Committee, dominated by people holding positions in Europe and the United States. These initial conditions could be a problem and it might take a long time to fix the situation. Nevertheless, as Ooguri explained, the Committee will come up with a process for elections and would like to welcome nominations for next year. What is more, any number of additional Committee members can be included. So, as the members rotate out, diversity will be enhanced even further. Finally, we were informed that a link to the Strings Planning Committee vote would be sent to us. During the closing session chaired by Ooguri on Friday, Sabrina was the Commissioner who announced the voting results, confirming the approval of the proposal. The last important thing I should add is that Strings 2024 and 2025 will likely be held at CERN and NYU Abu Dhabi respectively.

After the closing session, we had some time to interact and engage in informal conversations.

The most valuable words of knowledge and inspiration for me came from Maldacena, I believe. He shared with me some insights regarding non-planar corrections in relation to my work, I should write about that someday. Afterwards, I joined a group of participants to search for a suitable dining establishment at University Shop Plaza. On the way back, we met another group who were headed to Waterloo Park to see llamas. While there, Ooguri was approached by a llama. We speculated that the llama's interest might lie in learning string theory. On Saturday, I went back to the park and recorded this video of the geese. For lunch, I made the choice to indulge in Korean cuisine. The food was so good that I chose to have Korean food for my Sunday lunch as well. The restaurant's name is Seul Soul. I went there on both days, so if you ever find yourself in the vicinity, I recommend giving it a try. I didn't have time on this occasion, but next time I must find out if there is any Peruvian food place near PI.