Sabrina Pasterski is a theoretical physicist whose research addresses fundamental questions about gravity, quantum field theory, and the mathematical structures that connect them. Theoretical physicists use mathematical models to investigate how nature works, including in regimes that are difficult to probe directly through experiments. Pasterski’s work is associated with efforts to understand what happens to physical laws at very high energies and at the boundaries of spacetime, where familiar descriptions can reveal deeper patterns.

Several connected topics feature in this research. Scattering amplitudes are mathematical quantities used to calculate the likelihood of particles interacting or scattering; studying their structure can expose relationships that are not obvious in standard formulations. Asymptotic symmetries are transformations that preserve physical laws in the far-away regions of spacetime, such as the region approached by light traveling outward. Researchers examine how these symmetries relate to conservation laws and to the information carried by particles and fields. These ideas bring together methods from gravity and quantum field theory, rather than belonging exclusively to either subject.

Pasterski is also associated with celestial holography, a broader research program that explores whether processes in four-dimensional spacetime can be described using a theory on a two-dimensional celestial sphere. The sphere represents the directions from which incoming particles arrive or toward which outgoing particles travel. Holography, in this context, refers to the possibility that information about a higher-dimensional physical system can be encoded in a lower-dimensional description. Celestial holography is not a single theory created or owned by one researcher; it has developed through contributions by many physicists, including Pasterski and her collaborators. Its ideas remain under investigation, and researchers continue to test how useful the framework is, how it relates to established theories, and what physical insights it may provide. This makes the subject an evolving area of study, rather than a settled account of the universe.

The holographic principle is an idea about how physical information can be described, rather than a claim that the world is an image on a screen. In certain theoretical settings, a system with gravity in a volume of space can be mathematically equivalent to a theory defined on that space’s lower-dimensional boundary. The boundary description may encode the same physical content as the higher-dimensional account, despite using fewer dimensions. This possibility emerged from studies of black holes, whose entropy appears to scale with the area of an event horizon rather than the volume inside it. Such examples motivate researchers to ask whether spacetime and gravity can be understood through information organized in another form.

Celestial holography applies this broad perspective to particle physics in flat spacetime. Instead of describing a collision only in terms of particles moving through ordinary space and time, it reorganizes the collision’s outcomes as data associated with the celestial sphere. This sphere is the apparent sky surrounding an observer: directions on it indicate where incoming and outgoing particles travel. In the proposed framework, physical processes in the spacetime bulk are related to mathematical quantities arranged on this sphere. The change of viewpoint can make certain symmetries and relationships among particle interactions easier to investigate.

A central ingredient is the scattering amplitude, a quantity physicists use to calculate the likelihood of different outcomes when particles interact. Amplitudes can be transformed into a form suited to the celestial description, where particle energies and directions are represented in ways that resemble the data of a lower-dimensional theory. Researchers study whether these transformed amplitudes obey structures characteristic of a conformal field theory and what that might reveal about gravity and quantum physics. The correspondence remains a theoretical proposal under development, with important questions still open. It does not mean that the universe is literally projected onto a sky, nor that photographs of the astronomical sky contain a complete record of physical reality. Rather, celestial holography is a framework for translating and organizing scattering information, with the aim of uncovering equivalent descriptions of processes in flat spacetime.

Researchers find celestial holography promising because it offers a possible common language for questions that usually belong to separate areas of physics. Gravity describes spacetime and its large-scale geometry, quantum theory governs microscopic probabilities, and particle physics studies the interactions of elementary constituents. A framework that places these subjects in a shared setting could make their relationships easier to state and compare. This does not mean their longstanding tensions have been resolved. Rather, it gives researchers a way to organize concepts and ask whether structures familiar in one area have counterparts in another, especially in the study of scattering and gravity.

One important connection involves asymptotic symmetries: transformations that preserve relevant physical conditions near the far boundaries of spacetime. Although these boundaries lie far from the interaction region, their symmetries can constrain what scattering processes are allowed to do. In certain settings, such symmetry relations are connected to soft theorems, which describe how scattering amplitudes behave when an interaction emits a particle with very low energy. Studying the relationship may clarify why soft particles carry information about broader features of an interaction. It also offers a route for testing whether gravitational symmetries and particle-level calculations can be expressed in compatible terms.

Celestial observables provide another research opportunity by recasting scattering amplitudes—the quantities used to calculate outcomes of particle collisions—as data organized on the celestial sphere. This change of perspective may expose patterns that are less apparent in conventional descriptions, including links between symmetry, particle behavior, and spacetime geometry. Researchers can then investigate whether those patterns help connect ideas that have often been studied independently. The approach is not yet a complete account of quantum gravity, nor does a new representation automatically supply answers to foundational problems. Its potential value is more measured: it may provide useful structure for comparing theories, identifying fruitful questions, and guiding future calculations.

Celestial holography is an ambitious proposal for recasting gravitational scattering in terms of data defined at distant boundaries of spacetime. Its appeal depends on more than elegant analogies with familiar holographic ideas: researchers need a precise correspondence that maps physically meaningful observables across a broad range of settings and reproduces known results. At present, important formulations remain specialized or conjectural, and the relationship between asymptotic symmetries, scattering amplitudes, and boundary operators can depend on assumptions about the theory and its spacetime. Establishing where the construction applies, what information it preserves, and whether it extends beyond idealized cases is essential.

Mathematical consistency is equally important. A compelling framework must define its observables and symmetries unambiguously, explain how quantum corrections are handled, and demonstrate that calculations agree across independent methods. Questions about infrared divergences, boundary conditions, and realistic matter remain technically demanding. The approach also needs clearer links to measurable physics: scattering amplitudes are meaningful theoretical quantities, but connecting them to observations or distinctive signatures is not straightforward. Direct tests of quantum gravity may lie beyond current experimental reach, and much of this research is necessarily theoretical. That limitation does not invalidate the program, but it places a premium on testable consequences and transparent accounts of what evidence could support or challenge it.

Its significance should also be assessed alongside other quantum-gravity programs, including string theory, loop quantum gravity, and approaches based on quantum information. These frameworks address overlapping questions with different tools and assumptions; comparison requires specifying what celestial holography explains uniquely, where it offers calculational advantages, and how its claims relate to established results. Sabrina Pasterski’s work in this area has helped make these questions influential, but prominence is not itself proof of a breakthrough. The outlook is promising yet appropriately provisional: celestial holography may yield powerful insights into gravity and quantum field theory, while its long-term importance will depend on robust results that withstand scrutiny and clarify fundamental physical questions.