The rapid evolution of neutron-star astronomy in recent years is for the first time giving us empirical access to the physics of the cores of neutron-stars, the internal structure of which is determined by the equation of state (EoS) of strongly interacting matter. In this talk I demonstrate in a general and analytic way how high-density information about EoS of strongly interacting matter...
During inflation, quantum field fluctuations are placed in squeezed states which undergo quantum-to-classical transitions on super-Hubble scales, in the sense that the non-commutative parts of the fields then become small compared to their anti-commutative parts. An effective theory for the physics of the long-wavelength parts of quantum scalar fields in the super-Hubble regime is the...
In recent years a covariant 1/c-expansion of general relativity, known as non-relativistic gravity, has been developed. This new expansion has many interesting prospects but much is still unknown about it. One thing that remains unclear is what connection, if any, it has to the post-Newtonian approximation. So far, Non-relativistic gravity is believed to be a more general approximation that...
I will discuss how the geometry of the asymptotic infinities of 4-dimensional Minkowski spacetime is captured by homogeneous spaces of the Poincaré group. In addition to the blowups of spatial (Spi) and timelike (Ti) infinities a la Ashtekar-Hansen, which are (pseudo-)carrollian geometries, this construction naturally leads to a novel space Ni that fibers over scri and is equipped with a...
Motivated by higher spin scattering amplitudes in gravity, we review and compare the interactions of higher spin fields in different formalisms
Effective field theory (EFT) is a theory-agnostic approach to understanding how high-energy phenomena would manifest in our low-energy universe. It is an expansion in higher-dimension operators built out of light fields with unknown coefficients. These coefficients can either be constrained through experiment or by demanding consistency with theoretical expectations, such as causal wave...
Ultracompact objects with photonspheres are known to mimic many observational features of black holes. It has been suggested that anomalous tidal heating or the presence of resonances in gravitational-wave signals would be a clear imprint of a surface or the absence of a horizon. Such claims and studies are all based on a frequency-domain analysis, assuming stationarity. In this talk, we will...
Assuming any massless free-fields with spin higher than 1/2 are constructed by scalar fields (spin-0) and Dirac-Weyl fields (spin-1/2), we introduce a map between spin-2 massless free-fields (gravity fields) and Dirac-Weyl fields in spinor formalism, then associated Dirac-Weyl spinors that can live in certain spacetime are identified. Regarding them as basic units, other higher spin massless...
Quantum scattering amplitudes for massive matter have received new attention in connection to classical calculations relevant to gravitational-wave physics. Amplitude methods and insights are now employed for precision computations of observables needed for describing the gravitational dynamics of bound massive objects such as black holes. An important direction is the inclusion of spin...
The worldline quantum field theory (WQFT) formalism describes classical gravitational observables including spin effects up to quadratic order in the multipole expansion, and including finite-size corrections. The theory enjoys an N=2 worldline supersymmetry between spin and position degrees of freedom. Recently we have used the WQFT to compute gravitational observables at third...
