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In the present paper, we revisit gravitational theories which are invariant under TDiffs-transverse (volume-preserving) diffeomorphisms and global scale transformations. It is known that these theories can be rewritten in an equivalent diffeomorphism-invar ...
We discuss how nonrelativistic spacetime symmetries can be gauged in the context of the coset construction. We consider theories invariant under the centrally extended Galilei algebra as well as the Lifshitz one, and we investigate under what conditions th ...
The reciprocity between form and force diagrams in 2D graphic statics makes it possible to manipulate the form diagram while directly evaluating the redistribution of the forces within the force diagram. Conversely, after modifying the force diagram, the c ...
We study the renormalization group flow in strongly interacting field theories in the fermion sector corresponding to the transition from theories without a Lorentz invariance at high energies to theories with an approximate Lorentz invariance in the infra ...
Spontaneous symmetry breaking with necessity leads to the presence of Goldstone field(s). In the case of scale or conformal symmetries the corresponding Goldstone mode is called the dilaton. Consistently coupling a system to the dilaton poses certain diffi ...
We classify condensed matter systems in terms of the spacetime symmetries they spontaneously break. In particular, we characterize condensed matter itself as any state in a Poincare-invariant theory that spontaneously breaks Lorentz boosts while preserving ...
In this note we show that given a conformally invariant theory in flat space-time, it is not always possible to couple it to gravity in a Weyl invariant way. (C) 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY li ...
The Galilei group involves mass as a central charge. We show that the associated superselection rule is incompatible with the observed phenomenology of superfluid helium 4: this is recovered only under the assumption that mass is spontaneou.519 broken. Thi ...
Spatial compactification on R(3)xS(L)(1), at small S-1-size L often leads to a calculable vacuum structure, where various "topological molecules" are responsible for confinement and the realization of the center and discrete chiral symmetries. Within this ...
We study the geometrical properties of scale-invariant two-field models of inflation. In particular, we show that when the field-derivative space in the Einstein frame is maximally symmetric during inflation, the inflationary predictions can be universal a ...
