John F. Donoghue

Learn More
I describe the treatment of gravity as a quantum effective field theory. This allows a natural separation of the (known) low energy quantum effects from the (unknown) high energy contributions. Within this framework, gravity is a well behaved quantum field theory at ordinary energies. In studying the class of quantum corrections at low energy , the dominant(More)
In theories in which different regions of the universe can have different values of the the physical parameters, we would naturally find ourselves in a region which has parameters favorable for life. We explore the range of anthropically allowed values of the mass parameter in the Higgs potential, µ 2. For µ 2 < 0, the requirement that complex elements be(More)
We treat general relativity as an effective field theory, obtaining the full nonanalytic component of the scattering matrix potential to one-loop order. The lowest order vertex rules for the resulting effective field theory are presented and the one-loop diagrams which yield the leading nonrelativistic post-Newtonian and quantum corrections to the(More)
One of the puzzles of the Standard Model is why the mass parameter which determines the scale of the Weak interactions is closer to the scale of Quantum Chromodymanics (QCD) than to the Grand Unification or Planck scales. We discuss a novel approach to this problem which is possible in theories in which different regions of the universe can have different(More)
We examine the corrections to the lowest order gravitational interactions of massive particles arising from gravitational radiative corrections. We show how the masslessness of the graviton and the gravitational self interactions imply the presence of nonanalytic pieces ∼ −q 2 , ∼ q 2 ln −q 2 , etc. in the form factors of the energy-momentum tensor and that(More)
We use effective field theory techniques to examine the quantum corrections to the gravitational metrics of charged particles, with and without spin. In momentum space the masslessness of the photon implies the presence of nonanalytic pieces ∼ −q 2 , q 2 log −q 2 , etc. in the form factors of the energy-momentum tensor. We show how the former reproduces the(More)
A nonlinear dynamic model of the terminal voltagecurrent (V-I) characteristics of a mercury arc lamp operating at various power levels which can be used in the computer design of lamp ballast circuits is described. An experimental and efficient computational procedure is developed which determines the values for six model constants that cause the model to(More)