To see open hosted preprints and journal articles follow the inSPIRE link in the sidebar, or click here.
My group’s web page is hosted at http://fancyphysics.org, where you can find my recent grant proposals here.
Big Questions:
 What unifies our physical predictions?
 How does the relatively calm macroscopic universe survive and emerge from the violent quantum fluctuations of its underlying microphysics?
 How do classical notions of space and time emerge from fundamental principles, and what governs their evolution?
 How are should our classical understanding of space and time be modified to build intuition of underlying quantum reality?
 How might our current understanding of quantum mechanics need to evolve to resolve answers to the above questions?
Broad projects:
 Double copy unification of relativistic quantum field theories.
 Double copy relevance for classical predictions in perturbative gravity.
 Predictivity question re: pointlike quantum field theories of gravity. (Are all QFT of gravity effective out of necessity?)
 Relevance of fieldtheory doublecopy to ultrasoft properties of string theory. (See Ztheory.)
 Effective field theory of large scale structure (EFTofLSS)
 \(\alpha\)Attractor Inflationary models.
Research highlights:
 Discovered the colorkinematic duality in gauge theories and the associated doublecopy structure of tree and multiloop gravity theory amplitudes. Importance: Striking clarification of the intimacy between gauge and gravity theories, redundancy present in both, changing the way we calculate in and think about these theories. (For a textbook introduction can now see Anthony Zee’s Quantum Field Theory in a Nutshell, 2nd Ed., Chapter N.4. For popular science account see May 2012 cover story of Scientific American.)
_{ with: Bern, Johansson. }  Discovered the \((n3)!\) basis (“BCJ” basis) of gaugetheory treelevel amplitudes. Importance: Led to proofs of explicit treelevel gaugegravity amplitudelevel relations (KLT) in field theory, subsequent discovery of analogous structure in string theory led to closed form stringKLT expressions and allorder expressions for string treeamplitudes.
_{with: Bern, Johansson. }  Established, through explicit calculation, that the high energy behavior of \({\cal N}=8\) maximal supergravity, contrary to popular opinion, is much better than expected – matching the known finite maximal gauge theory – through 4 loops as of now. Importance: If finite to all orders it is because of an unrecognized symmetry or mechanism whose apprehension will teach something very new about gravity.
_{ with: Bern, Dixon, Kososwer, Roiban, Johansson. }  Established the predictive impact of certain anomalies relevant to \({\cal N}\le4\) supergravity theories, and perhaps more strikingly their underlying doublecopy origins. Importance: There is mounting evidence to suggest that failure of predictivity for pure supergravity theories in fourdimensions are directly related to these anomalies, which * do not exist for \({\cal N}>5\) supergravity theories.*
_{with: Kallosh, Roiban, Tseytlin.}  Established the effective field theory of cosmological largescale structure. Importance: opens up a rigorous new way to analytically study largescale structure taking into account the nonlinearity of smallscale perturbations with telling agreement between numerical simulations and analytic theory.
_{with: Foreman, Green, Hertzberg, Senatore.}  Discovered a systematic, theoryindependent, approach to unitaritybased multiloop perturbative quantization  Method of Maximal Cuts. Importance: Establishes hierarchy of relevance of \(S\)matrix information for a given theory. Trivialized unitarity statesums for theories whose spectra are truncations of \({\cal N}=4\) super YangMills^{1} in 4D to just tracking glue around MHVvertex graphs.
_{with: Bern, Dixon, Kosower, Roiban, Johansson.}  Established covariant prescriptions for deforming nonlinear dualityinvariant theories. Importance: demonstration of freedom to introduce counterterms to theories protected by dualityinvariance, may be relevant to UV questions in gravity.
_{with: Broedel, Ferrara, Kallosh, Roiban}  Established Ztheory as the effective bicolored scalar theory which encodes all the \(\alpha'\) corrections of the openstring, and thus encodes all the ultrasoft UV behavior. Importance: Scalars theories are technically much simpler to analyze. Ztheory amplitudes offer a fascinating laboratory to study the emergence of stringybehavior in a new and technically much simpler context.
_{ with: Mafra and Schlotterer}

So, also, theories that are orbifolds of \({\cal N}=8\) supergravity. ↩