I have been invited to give a personal account of the early history of string theory. I have decided to interpret this as the period 1968-1985. After 1985 the subject began to receive widespread interest and acceptance,and has remained very active ever since. The talk will be divided into four sections.

I: The 1960s; 

II: The First String Theories; 

III: Gravity and Unification; 

IV: Anomalies and Their Cancellation. 

Works by me and my collaborators, especially André Neveu Neveu, Joël Scherk, Lars Brink, and Michael Green, will be emphasized. I will pause for questions at the end of each section.

The Heisenberg group is the simplest example of a noncommutative nilpotent Lie group. In this talk, we will explore how that noncommutativity affects geometry and analysis in the Heisenberg group. We will describe why good embeddings of $\mathbb{H}$ must be "bumpy" at many scales, how to study embeddings into $L_1$ by studying surfaces in $\mathbb{H}$, and how to construct a metric space which embeds into $L_1$ and $L_4$ but not in $L_2$. This talk is joint work with Assaf Naor.

Associative Memories like the famous Hopfield Network are elegant models for describing fully recurrent neural networks whose fundamental job is to store and retrieve information. However, despite their immense popularity in the '80s and '90s, Associative Memories have been mostly forgotten in today's AI landscape. In this talk I provide an approachable overview to Associative Memories, emphasizing modern formulations that reveal remarkable overlap with the fundamental operations of Diffusion Models and even Transformers.

Biological neurons are optimized through evolution to manage complex systems in dynamic, changing environments. This talk explores spiking neural networks (SNN) as a natural approach to handling complex spatiotemporal data. We present Adaptive SNN architecture that is able to efficiently handle dynamic multimodal inputs in unsupervised and reinforcement learning setups. We also showcase examples of real-world applications that have been enabled by this advanced signal recognition and control strategy.

Singular learning theory (SLT) suggests a correspondence between: structure of the data; internal algorithmic structure of a neural network; geometry of the loss landscape; and structure of the learning process. This provides a basis for developing tools & theory to interpret what neural networks learn and how they learn it. In this talk, we present an introduction to SLT, survey recent evidence for different parts of this correspondence, and sketch future directions and applications within AI safety & interpretability.

Geometric Phase in matter can be described in terms of fiber bundle holonomy. The complex order in a ferromagnetic system can lead to spontaneously broken symmetries with topological invariants. The Toric quantum error correction codes generated by entangled entropy can reveal the underlying topological order of a spin liquid.

Most social processes have mechanisms we do not understand, and unpredictable outcomes. Social status determination is an exception to this dismal social science record.  Evidence from multiple sources in England from 1600 to 2024 – extensive genealogies, and surname distributions – suggests the inheritance of status follows simple, stable rules throughout this period.  These rules are consistent with additive genetic determination of social status in the presence of strong genetic assortment in mating.

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Traditional tribal secret societies have been undertheorized in anthropology, yet they may have played a pivotal role in initiating the rapid acceleration of cultural complexity beginning in the Upper Paleolithic and continuing until today.  I suggest that secret societies constituted the first non-kinship based institutions in culture history and that they constituted good examples of  complex self-organizing adaptive cultural systems capable of overcoming the egalitarian constraints of the previous 2 million years.

Political epistemology is a growing subfield in the philosophical study of belief, knowledge, and justification. In this talk I explain the various types of questions and approaches within political epistemology, including inquiries into the rationality and irrationality of political beliefs, into psychological and sociological causes of political belief, institutional design from an epistemic perspective, and the putative political nature of epistemology itself.