Senior Nuclear Theorist Body Physics; m​/f​/d

Lead the nuclear theory behind a new approach to fusion energy.

At Snap Fusion, we are pursuing a bold mission: developing a fundamentally new approach to controlled fusion energy.

Parts of our roadmap rest on questions of low-energy nuclear physics. Some of these have clear answers in the literature; others turn out, on close reading, to be less settled than they first appear. Knowing which is which matters to us, because it shapes what we build and what we test.

We are therefore establishing an in-house nuclear theory effort, and we are looking for a senior few-body theorist to lead it. Your job will be to decide which of our questions current theory can actually answer, to answer those at a standard that would hold up to expert review, and to say plainly where the uncertainties lay.

This is an unusual setting for a theorist, in a good way: the questions are concrete, the team is small, and your conclusions will be acted on.

You will work directly with the founders as theory lead. Your responsibilities may include:

• Leading theory projects from problem definition to a clear recommendation
• Judging which questions current nuclear theory can answer, and with what uncertainty
• Carrying out and supervising few-body scattering and reaction calculations
• Setting the benchmarks and cross-checks against which results are accepted
• Working with our computational physics lead on the numerical implementation of the methods you specify
• Reviewing theoretical and experimental claims that bear on our roadmap
• Building collaborations with academic groups, including for independent confirmation of key results
• Helping the rest of the team understand the physics behind your conclusions

Your assessments will directly inform Snap Fusion's technology roadmap.

You will probably hold a PhD in theoretical nuclear physics or a closely related field, with research experience beyond it. Ideal candidates will have strong experience in several of the following areas:

Nuclear theory

• Quantum scattering and reaction theory
• Few-body or ab initio methods
• Realistic nuclear interactions
• Resonances, thresholds, and continuum physics
• Low-energy charged-particle reactions
• Fusion cross sections and astrophysical S-factors

Scientific leadership. You should be comfortable:

• Running a research program with milestones and honest go/no-go decisions
• Saying that a question cannot be answered with current theory, when it cannot
• Writing clearly for readers who are not few-body specialists
• Reviewing other people's derivations, and having your own reviewed

Like most few-body theorists, you will have done a good deal of numerical work, and that experience will be valuable here. But this is a physics role first: we have a computational physics lead, and implementation is a collaboration rather than the core of your job.

Industry experience is not required.

Experience with any of the following is a plus:

• Light-nuclei reaction calculations
• R-matrix or related continuum methods
• Nuclear astrophysics
• Benchmark comparisons between methods or codes
• Close collaboration with experimentalists
• Refereeing and reviewing
• Teaching or mentoring

You may be a great fit if:

• You like physics questions with practical consequences
• You would rather establish a modest result firmly than a striking one loosely
• You are comfortable saying “we don't know yet” and explaining why
• You enjoy making difficult material clear to colleagues from other fields
• You want to see your work used

This role suits someone who wants to keep doing serious theory while seeing it put to use.

The questions you settle will feed into research in:

• Fusion energy
• Scientific discovery
• Advanced simulation
• AI for Physics
• Quantum technologies

You will work alongside physicists and engineers on problems where careful theory has direct consequences. The work is early, the questions are real, and the standard is high.