Phantom without UV pathology

Abstract

We present a simple model in which the weak energy condition is violated for spatially homogeneous, slowly evolving fields. The excitations about Lorentz-violating background in Minkowski space do not contain ghosts, tachyons or superluminal modes at spatial momenta ranging from some low scale epsilon to the UV cutoff scale, while tachyons and possibly ghosts do exist at p^2 < epsilon^2. We show that in the absence of other matter, slow roll cosmological regime is possible; in this regime p+rho<0, and yet homogeneity and isotropy are not completely spoiled (at the expence of fine-tuning), since for given conformal momentum, the tachyon mode grows for short enough period of time.

19 pages. Several misprints corrected, several points clarified, several references added

References in corpus (18)

• 4D Gravity on a Brane in 5D Minkowski Space
• A Phantom Menace? Cosmological consequences of a dark energy component with super-negative equation of state
• Causality, Analyticity and an IR Obstruction to UV Completion
• Reconstruction of a scalar-tensor theory of gravity in an accelerating universe
• Braneworld models of dark energy
• The phantom menaced: constraints on low-energy effective ghosts
• Can dark energy evolve to the Phantom?
• The Cosmology of Generalized Modified Gravity Models
• Classical and Quantum Consistency of the DGP Model
• Null energy condition and superluminal propagation
• Lorentz-Violating Vector Fields Slow the Universe Down
• Crossing the Phantom Divide: Dark Energy Internal Degrees of Freedom
• How a brane cosmological constant can trick us into thinking that w < -1
• Can we be tricked into thinking that w is less than -1?
• Modified Gravity via Spontaneous Symmetry Breaking
• Instabilities and the null energy condition
• More about spontaneous Lorentz-violation and infrared modification of gravity
• Modified Gravitational Theory as an Alternative to Dark Energy and Dark Matter

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• The Viability of Phantom Dark Energy: A Brief Review
• Neutron stars in Einstein-aether theory
• Numerical simulations of gravitational collapse in Einstein-aether theory
• Black holes in the presence of dark energy
• Dynamics in Nonlocal Cosmological Models Derived from String Field Theory
• Non-local SFT Tachyon and Cosmology
• On the Null Energy Condition and Cosmology
• Cheng-Weyl Vector Field and its Cosmological Application
• UV stable, Lorentz-violating dark energy with transient phantom era
• Relaxation of the Cosmological Constant
• Consistent NEC-violation: towards creating a universe in the laboratory
• Cosmological perturbations in SFT inspired non-local scalar field models
• Localization of nonlocal cosmological models with quadratic potentials in the case of double roots
• Born Again Universe
• Inertial mechanism: dynamical mass as a source of particle creation
• Risking your NEC
• Universally Coupled Massive Gravity, II: Densitized Tetrad and Cotetrad Theories
• Cosmological Consequences of Domain Walls Biased by Quantum Gravity
• Self-accelerating solutions of scalar-tensor gravity
• Phantom dark energy with tachyonic instability: metric perturbations
• CMB anisotropy induced by tachyonic perturbations of dark energy
• Are we seeing the beginnings of Inflation?
• Phantom Dirac-Born-Infeld Dark Energy
• CMB Anomalies from Imperfect Dark Energy: Confrontation with the Data
• Possibility of cyclic Turnarounds In Brane-world Scenario: Phantom Energy Accretion onto Black Holes and its consequences
• Quantum Quintom Cosmology