The International Congress of Mathematicians (ICM) is where mathematicians come to present groundbreaking research and to receive the highest honors in the field, including the Fields Medals. Held every four years, this flagship event will return to an in-person format in July 2026, when it will be based in Philadelphia. This is the first time in four decades that the United States has hosted the ICM. Over 6,000 participants are expected. With philanthropic funding from Sloan and other foundations, the American Mathematical Society will ensure broad global representation by providing travel support to 658 mathematicians who, because they come from under-resourced  communities and countries, would not be able to attend otherwise. Outreach plans include mathematical exhibits and events designed for the public generally and for young people in particular. By lowering barriers to participation, this grant will enable broader engagement with mathematics and with mathematicians from around the world. 

Funds from this grant support research by Patrick Oakes and Jordan Beach, both Professors in the Department of Cell and Molecular Physiology at Loyola University Chicago, to better understand how a cell’s energy supply is linked to the mechanical forces it generates—an important gap in our understanding of how cells regulate energy resources to coordinate basic functions such as movement, division, and changes in shape. Oakes, Beach, and their team will use Sloan funding to measure how cellular ATP levels (the primary form of usable energy in cells) relate to force generation by the actomyosin cytoskeleton, an intracellular protein network that drives contraction and is a key player in cell division and motion. The work will be done using live cells, with experiments that both increase and decrease ATP  availability to see how the actomyosin skeleton responds, as well as with experiments that stimulate cytoskeletal activity to see how cellular ATP levels and other major energy-consuming processes respond. The project will also examine these relationships at finer spatial scales inside cells. Using imaging-based metabolic sensors and force-measurement methods, the research team will map and quantify where ATP is higher or lower inside the cell and compare those patterns with where contractile forces are generated. They will also field a series of experiments where ATP levels are manipulated in localized regions while observing the behavior of the corresponding section of the cytoskeletal network. If successful, the project will produce quantitative measurements describing how cellular energy availability and mechanical force generation influence one another at both whole-cell and subcellular scales, along with datasets and analysis that can help clarify how cells regulate mechanical behavior.

Funds from this grant provide continuing support for efforts by researchers at JILA/University of Colorado, Boulder to build advanced instrumentation capable of detecting new fundamental particles through precision measurement of the distortions these particles cause to the distribution of electric charge in an electron. A team led by JILA Fellows Eric Cornell and Jun Ye will use laboratory-generated electric fields to trap and hold molecular ions, which can then be measured to detect deformations in their electrical charge. Held still, ions can be monitored for thousands of times longer than if they were in motion, thereby increasing the probability of a successful detection of a charge-distorting particle. Prior efforts using this technique by Cornell and Ye have successfully yielded a new upper limit on EDM measurement in 2023. Using Sloan funds, the team seeks to improve upon their prior, successful efforts in several ways. First, they will switch from hafnium fluoride (HfF+) to thorium fluoride ions (ThF+) as the primary ion used for detection. This will result in greater sensitivity, as thorium is known to be more sensitive to the sorts of electrical distortions the group is attempting to measure. Second, Cornell and Ye will work to boost the ‘coherence time’ of the molecules in their experiment. This represents the time interval during which the molecules remain in well-defined, laser-prepared energy states that are useful for an eEDM measurement. Finally, the group will experiment with a number of approaches that promise to boost the number of ions that can be measured at one time from a few thousand to a few hundred thousand. Taken together, the improvements are expected to increase the sensitivity of their prior measurement by a factor of 4.  In parallel, Cornell and Ye will study the systematic errors associated with their trapped-molecules approach to EDM measurement with a focus on determining the root causes of systematic errors they encounter as well as determining the factors that affect the magnitude of those errors.

As the expansion of data centers across the United States raises questions about the adequacy of the country’s existing energy supply and infrastructure, many large data centers have begun to consider nuclear power as a potential source of low-carbon electricity. In particular, one proposed solution to meeting the electricity demand growth from data centers is to co-locate this infrastructure with nuclear power generation, whether that be existing nuclear power plants or next-generation nuclear power sources.This grant supports an interdisciplinary research team among scholars based at the University of Michigan, Massachusetts Institute of Technology, and Pittsburgh Technical to assess how data centers and nuclear power generation be co-located. Following an initial landscaping overview, the team will conduct five case studies to identify current and future locations for data center buildout and quantify their associated electricity demand, analyzing technical, economic, legal, regulatory, and safety dimensions. They will also study alternative business models to assess the viability of co-locating data centers and nuclear power generation. They will also study public responses to the co-location of nuclear power and data centers alongside various legal and safety implications of data center and nuclear power co-location, and they will draw on the expertise of an Advisory Committee to inform the case study site selection and research process.

This grant supports experiments to assess whether “xenobiotic nucleic acids” (XNAs)—DNA/RNA-like polymers not found in nature—could serve as alternative carriers of genetic information, with implications for understanding possible early-life chemistries and for building simplified synthetic cells. A team led by Lijun Zhou at the University of Pennsylvania will use Sloan funding to characterize how efficiently and how accurately a specific class of XNA polymers (NP-DNA and NP-RNA) can be copied from a template without the use of enzymes. The work will measure copying speed and error rates across a diverse range of XNA sequences and varying environmental conditions (such as pH, temperature, and ion concentrations). The team will also investigate how the addition of reactivity-enhancing biomolecules affects copying speed and fidelity and whether and how genetic information could be transferred between the two types of polymers. In addition, the project team will run laboratory evolution experiments to determine whether these XNAs can undergo Darwinian evolution to expand their functionality, focusing on evolving XNA sequences that can catalyze useful reactions, such as joining short XNA strands together.

Despite advancements in clean energy generation, fossil fuels continue to play an important role in the energy system, especially when it comes to providing back-up power generation and ensuring household-level energy security. However, there is limited understanding of how fossil fuels are utilized at the household level to bolster energy resiliency, as well as how natural gas infrastructure is expanding as new homes are connected to the gas grid.Researchers from Arizona State University, Temple University, and University of Pennsylvania, in collaboration with experts at M Cubed Consulting, will map the growth and persistence of natural gas, back-up generation, and deliverable fuel networks across the United States, using permitting information, economic data, and remote sensing information to better understand patterns of adoption for these power sources. The team will also conduct qualitative interviews with industry members to examine the structure and organization of back-up power fossil fuel networks. To complement this analysis, they will undertake two detailed case studies in Phoenix, Arizona and Central Pennsylvania to explore in-depth how such back-up power fossil fuel utilization plays out at the household level in different regions of the country.