Theories with Memory

Dimensionally reduced supersymmetric theories retain a great deal of information regarding their higher dimensional origins. In superspace, this "memory" allows us to restore the action governing a reduced theory to that describing its higher-dimensional progenitor. We illustrate this by restoring four-dimensional N=4 Yang-Mills to its six-dimensional parent, N=(1,1) Yang-Mills. Supersymmetric truncation is introduced into this framework and used to obtain the N=1 action in six dimensions. We work in light-cone superspace, dealing exclusively with physical degrees of freedom.Comment: 18 pages, reference adde

Light-cone gravity in dS4_4

We derive a closed form expression for the light-cone Lagrangian describing pure gravity on a four-dimensional de Sitter background. We provide a perturbative expansion, of this Lagrangian, to cubic order in the fields.Comment: 11 page

Factorization of cubic vertices involving three different higher spin fields

We derive a class of cubic interaction vertices for three higher spin fields, with integer spins $\lambda_1$, $\lambda_2$, $\lambda_3$, by closing commutators of the Poincar\'e algebra in four-dimensional flat spacetime. We find that these vertices exhibit an interesting factorization property which allows us to identify off-shell perturbative relations between them.Comment: 7 page

Maximal supergravity and the quest for finiteness

We show that N = 8 supergravity may possess an even larger symmetry than previously believed. Such an enhanced symmetry is needed to explain why this theory of gravity exhibits ultraviolet behaviour reminiscent of the finite N = 4 Yang-Mills theory. We describe a series of three steps that leads us to this result.Comment: 7 pages, Honorable Mention - Gravity Research Foundation 201

Yang-Mills theories and quadratic forms

We show that the Hamiltonian of (N=1;d=10) super Yang-Mills can be expressed as a quadratic form in a very similar manner to that of the (N=4;d=4) theory. We find a similar quadratic form structure for pure Yang-Mills theory but this feature, in the non-supersymmetric case, seems to be unique to four dimensions. We discuss some consequences of this feature.Comment: 12 page