# Richard Nally, Pappalardo Fellow

**Name**: Richard Nally**Title**: Pappalardo Fellow in Physics: 2024-2027**Email**: rnally@mit.edu**Phone**: (954) 850-3317**Office**: MIT Department of Physics

77 Massachusetts Avenue, 6C-409

Cambridge, MA 02139

Related Links:

Pappalardo Fellowships in Physics

## Area of Physics

## Research Interests

Richard Nally’s research is centered on string theory and its compactifications to four dimensions. String theory is defined in ten dimensions. To connect this theory to our familiar four dimensions, we take six of the ten dimensions to be compact, and the shape of the compact dimensions determines the physics in the four large dimensions. In the best-studied framework for these compactifications, we take the compact dimensions to be a special type of shape called a Calabi-Yau manifold. Richard’s research concerns these shapes and the physics of their compactifications.

A fundamental fact about our universe is that its expansion is accelerating. The leading proposal for how to realize this behavior in a string compactification was made by Kachru, Kallosh, Linde, and Trivedi (KKLT) in 2003, but an actual example of their proposed mechanism remained elusive for twenty years. In recent work, Richard and his collaborators constructed the first completely explicit examples of string compactifications realizing the KKLT mechanism for obtaining an accelerating universe in string theory. This work will be the starting point for Richard’s future research activities.

In addition to his work on constructing realistic solutions of string theory, Richard is also interested in connections between string theory and mathematics. In particular, he has worked extensively on relating special solutions of string theory to number theory, and has established physical criteria for the modularity of certain Calabi-Yau manifolds.

## Biographical Sketch

Richard was born and raised in Fort Lauderdale, Florida. He went to Brown University for college, where he received an ScB in Mathematical Physics. While at Brown, he pursued research in both experimental and theoretical aspects of Large Hadron Collider physics, under the mentorship of Profs. Meenakshi Narain and Chung-I Tan, respectively.

After Brown, Richard proceeded to get his PhD from Stanford University. Working with Prof. Shamit Kachru, Richard explored connections between string theory and number theory, and in particular worked to understand the role number theoretic objects called modular forms play in string theory. He additionally pursued projects in holography and aspects of theoretical condensed matter research.

From Stanford, Richard was awarded a Klarman Fellowship to pursue postdoctoral research at Cornell University. At Cornell, he worked with Prof. Liam McAllister to study explicit string compactifications and their physics. This productive collaboration led to the construction of the first-ever de Sitter vacua in Calabi-Yau compactifications of string theory.

Outside of physics, Richard is passionate about coffee, fashion, and cooking.

## Selected Publications

- L. McAllister, J. Moritz, R. Nally and A. Schachner, Candidate de Sitter Vacua, 2406.13751.
- N. Gendler, N. MacFadden, L. McAllister, J. Moritz, R. Nally, A. Schachner et al., Counting

Calabi-Yau Threefolds, 2310.06820.

- S. Kachru, R. Nally and W. Yang, Supersymmetric Flux Compactifications and Calabi-Yau

Modularity, 2001.06022.

- S. Kachru, R. Nally and W. Yang, Flux Modularity, F-Theory, and Rational Models,

2010.07285.

- R. Nally, Exact Half-BPS Black Hole Entropies in CHL Models from Rademacher Series, JHEP 01 (2019) 060, [1803.10775].