Speaker
Description
We present the basis of dimension-eight operators associated to
universal theories. We first derive a complete list of independent
dimension-eight operators formed with the Standard Model bosonic
fields characteristic of such universal new physics
scenarios. Without imposing C nor P the basis contains 175 operators
- this is, the assumption of Universality reduces the number of
independent SMEFT coefficients at dimension eight from 44807 to 175.
89 of the 175 universal operators are included in the general
dimension-eight operator basis in the literature. The 86 additional
operators involve higher derivatives of the Standard Model bosonic
fields and can be rotated in favor of operators involving fermions
using the Standard Model equations of motion for the bosonic fields.
By doing so we obtain the allowed fermionic operators generated in this
class of models which we map into the corresponding 86 independent
combinations of operators in the dimension-eight basis of
arXiv:2005.00059.
