String Photini at the LHC (2009)
Arvanitaki, Asimina, Craig, Nathaniel, Dimopoulos, Savas, Dubovsky, Sergei, March-Russell, John
String theories with topologically complex compactification manifolds suggest the simultaneous presence of many unbroken U(1)'s without any light matter charged under them. The gauge bosons...
Signatures of a Graviton Mass in the Cosmic Microwave Background (2009)
Dubovsky, Sergei, Flauger, Raphael, Starobinsky, Alexei, Tkachev, Igor
There exist consistent low energy effective field theories describing gravity in the Higgs phase that allow the coexistence of massive gravitons and the conventional 1/r potential of gravity. In an...
Arvanitaki, Asimina, Dimopoulos, Savas, Dubovsky, Sergei, Kaloper, Nemanja, March-Russell, John
String theory suggests the simultaneous presence of many ultralight axions possibly populating each decade of mass down to the Hubble scale 10^-33eV. Conversely the presence of such a plenitude of...
Decaying Dark Matter as a Probe of Unification and TeV Spectroscopy (2009)
Arvanitaki, Asimina, Dimopoulos, Savas, Dubovsky, Sergei, Graham, Peter W., Harnik, Roni, Rajendran, Surjeet
In supersymmetric unified theories the dark matter particle can decay, just like the proton, through grand unified interactions with a lifetime of order of 10^{26} sec. Its decay products can be...
The Volume of the Universe after Inflation and de Sitter Entropy (2008)
Dubovsky, Sergei, Senatore, Leonardo, Villadoro, Giovanni
We calculate the probability distribution for the volume of the Universe after slow-roll inflation both in the eternal and in the non-eternal regime. Far from the eternal regime the probability...
Astrophysical Probes of Unification (2008)
Arvanitaki, Asimina, Dimopoulos, Savas, Dubovsky, Sergei, Graham, Peter W., Harnik, Roni, Rajendran, Surjeet
Traditional ideas for testing unification involve searching for the decay of the proton and its branching modes. We point out that several astrophysical experiments are now reaching sensitivities...
Superluminal Travel Made Possible (in two dimensions) (2008)
Dubovsky, Sergei, Sibiryakov, Sergey
We argue that superluminal signal propagation is possible in consistent Poincare invariant quantum field theories in two space-time dimensions, provided spatial parity is broken. This happens due to...
Superluminal Travel Made Possible (in two dimensions) (2008)
Dubovsky, Sergei, Sibiryakov, Sergey
We argue that superluminal signal propagation is possible in consistent Poincare invariant quantum field theories in two space-time dimensions, provided spatial parity is broken. This happens due to...
The Phase Transition to Eternal Inflation (2008)
Creminelli, Paolo, Dubovsky, Sergei, Nicolis, Alberto, Senatore, Leonardo, Zaldarriaga, Matias
For slow-roll inflation we study the phase transition to the eternal regime. Starting from a finite inflationary volume, we consider the volume of the universe at reheating as order parameter. We...
(No) Eternal Inflation and Precision Higgs Physics (2008)
Arkani-Hamed, Nima, Dubovsky, Sergei, Senatore, Leonardo, Villadoro, Giovanni
Even if nothing but a light Higgs is observed at the LHC, suggesting that the Standard Model is unmodified up to scales far above the weak scale, Higgs physics can yield surprises of fundamental...
Microcausality in Curved Space-Time (2007)
Dubovsky, Sergei, Nicolis, Alberto, Trincherini, Enrico, Villadoro, Giovanni
It is well known that in Lorentz invariant quantum field theories in flat space the commutator of space-like separated local operators vanishes (microcausality). We provide two different arguments...
Bumpy black holes from spontaneous Lorentz violation (2007)
Dubovsky, Sergei, Tinyakov, Peter, Zaldarriaga, Matias
We consider black holes in Lorentz violating theories of massive gravity. We argue that in these theories black hole solutions are no longer universal and exhibit a large number of hairs. If they...
A Measure of de Sitter Entropy and Eternal Inflation (2007)
Arkani-Hamed, Nima, Dubovsky, Sergei, Nicolis, Alberto, Trincherini, Enrico, Villadoro, Giovanni
We show that in any model of non-eternal inflation satisfying the null energy condition, the area of the de Sitter horizon increases by at least one Planck unit in each inflationary e-folding. This...
Quantum Horizons of the Standard Model Landscape (2007)
Arkani-Hamed, Nima, Dubovsky, Sergei, Nicolis, Alberto, Villadoro, Giovanni
The long-distance effective field theory of our Universe--the Standard Model coupled to gravity--has a unique 4D vacuum, but we show that it also has a landscape of lower-dimensional vacua, with the...
Causality, Analyticity and an IR Obstruction to UV Completion (2006)
Adams, Allan, Arkani-Hamed, Nima, Dubovsky, Sergei, Nicolis, Alberto, Rattazzi, Riccardo
We argue that certain apparently consistent low-energy effective field theories described by local, Lorentz-invariant Lagrangians, secretly exhibit macroscopic non-locality and cannot be embedded in...