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In this talk I will primarily focus on how recent experiments strongly constrain the possible pairing symmetry in superconducting twisted bilayer graphene(TBG). After providing a short but self-contained introduction to pairing symmetry which arguably is the most important characterization of a superconductor, I will discuss experimental evidence that strongly suggests that superconductivity in TBG descends from a spin valley locked normal state with broken spin rotation symmetry. Consequently, we get an admixture of singlet and triplet pairing. I shall discuss how the observation of the spectacular phenomenon of nematicity in the superconducting phase further constrains the orbital part of the pair wave function to be either a p-wave or a d-wave. On a different note, I will introduce a new way of thinking about pairing symmetry in general, that we have recently developed, which allows us to establish a connection between pairing symmetry and the fermionic projective symmetry group(PSG). The PSG in turn controls important properties like the presence/ absence of a Majorana zero mode bound to the core of an Abrikosov vortex in the superconductor.
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