A linear counterterm can be chosen so that the renormalized one-point function, or equivalently the chosen vacuum expectation value, is zero. This cancels attached tadpole diagrams in the perturbative expansion about that vacuum. In a massive six-dimensional cubic scalar field theory, the one-loop proper tadpole is ; without subtraction the stationary background shifts by at one-loop order. One must specify this convention when comparing reducible exchange diagrams or mass corrections.
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