The Quintom scenario (derived from the words ''
quintessence'' and ''phantom'', as in
) is a hypothetical model of
dark energy
In physical cosmology and astronomy, dark energy is an unknown form of energy that affects the universe on the largest scales. The first observational evidence for its existence came from measurements of supernovas, which showed that the univ ...
.
Equation of State
In this scenario, the
equation of state
In physics, chemistry, and thermodynamics, an equation of state is a thermodynamic equation relating state variables, which describe the state of matter under a given set of physical conditions, such as pressure, volume, temperature, or intern ...
of the dark energy, relating its
pressure
Pressure (symbol: ''p'' or ''P'') is the force applied perpendicular to the surface of an object per unit area over which that force is distributed. Gauge pressure (also spelled ''gage'' pressure)The preferred spelling varies by country and e ...
and
energy density, can cross the boundary
associated with the cosmological constant. The boundary separates the phantom-energy-like behavior with
from the quintessence-like behavior with
. A
no-go theorem shows that this behavior requires at least two degrees of freedom for dark energy models involving ideal gases or scalar fields.
The Quintom scenario was applied in 2008 to produce a model of
inflationary cosmology
In physical cosmology, cosmic inflation, cosmological inflation, or just inflation, is a theory of exponential expansion of space in the early universe. The inflationary epoch lasted from seconds after the conjectured Big Bang singularit ...
with a
Big Bounce instead of a
Big Bang singularity.
References
External links
Dark Energy Constraints from the Cosmic Age and Supernova by Bo Feng, Xiulian Wang and Xinmin Zhang
Crossing the Phantom Divide by Martin Kunz and Domenico Sapone
Dark energy
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fr:Énergie fantôme
it:Energia fantasma