Effective Field Theories (EFTs) allow us to describe low energy physics without knowing the specific UV completion. This comes at the cost of having free parameters (Wilson coefficients) whose values encode the UV physics, but are not constraint from a standard EFT point of view. It is well known that some values can lead to unphysical properties of these theories. In this talk, I will present a low energy technique to put bounds on these coefficients by requiring causal propagation. I will show how these bounds can be obtained in flat space and then move on to how apply these techniques in cosmological spacetimes. Throughout the talk I will present bounds on scalar and photon EFTs.

In this talk I will introduce the double copy construction that allows us to write gravitational scattering amplitudes as the "square" of gauge theory ones. I will show how the standard construction can be generalized to include massive mediators and how this relationship can also be observed for classical solutions in coordinate space as well as for cohomology class representatives in twistor space. Throughout the talk I will focus on the example of Topologically Massive Theories.

The double copy in its original form allows us to obtain scattering amplitudes of gravity as the "square" of those of Yang Mills. I will explain how this squaring procedure works and how this relationship has been extended to classical solutions. I will also briefly mentioned how the double copy relationship can be extended to scalar effective field theories. [please email a.held@imperial.ac.uk for zoom link or password]