We study an infinite family of Massive Type IIA backgrounds that holographically describe the twisted compactification of N=(1,0) six-dimensional SCFTs to four dimensions. The analysis of the branes involved suggests a four dimensional linear quiver QFT, that deconstructs the theory in six dimensions. For the case in which the system reaches a strongly coupled fixed point, we calculate some observables that we compare with holographic results. Two quantities measuring the number of degrees of freedom for the flow across dimensions are studied.
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𝑉_{𝑢𝑏} is the smallest and least known of all CKM matrix elements; it's currently determined primarily through the exclusive process B \to \pi \ell \bar{
u}. I will present progress toward a lattice QCD determination of the 𝑉_{𝑢𝑏} matrix element from a novel transition -- the B \to \pi \pi \ell \bar{
u} process, where the π π system is in a P-wave and features the \rho(770) resonance as an enhancement. The calculation is performed an ensemble with 𝑁_𝑓=2+1 isotropic clover fermions wiht 𝐿≈3.6 fm and a pion mass of 320 MeV; for the b-quark we use the anisotropic clover action. After a brief overview of the theoretical framework, I will discuss some preliminary results.
I will discuss how cutting-edge amplitudes methods can be applied to the study of classical binary dynamics in general relativity relevant to gravitational wave physics. After a more general overview I will introduce the heavy mass effective field theory (HEFT) as an efficient implementation of these ideas to compute the classical deflection angle and waveforms in GR. I will also describe a novel version of the color-kinematics duality for amplitudes in HEFT and Yang-Mills and discuss its underlying kinematic Hopf algebra.
I will begin with a slow introduction to the amplituhedron, carefully explaining how to extract N=4 SYM amplitudes from it in detail. Then I will point out a couple of subtleties with the procedure in the literature, in particular showing that the lop amplituhedron is not a positive geometry as previously defined. We will thus extend the definition of positive geometries and further propose a more general mathematical space "weighted positive geometry". We will also discuss implications for the "deepest cut" of the amplitude.