The curvaton is a hypothetical
elementary particle
In particle physics, an elementary particle or fundamental particle is a subatomic particle that is not composed of other particles. The Standard Model presently recognizes seventeen distinct particles—twelve fermions and five bosons. As a c ...
which mediates a
scalar field
In mathematics and physics, a scalar field is a function associating a single number to each point in a region of space – possibly physical space. The scalar may either be a pure mathematical number ( dimensionless) or a scalar physical ...
in early universe
cosmology
Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe, the cosmos. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', with the meaning of "a speaking of the wo ...
. It can generate fluctuations during
inflation
In economics, inflation is an increase in the average price of goods and services in terms of money. This increase is measured using a price index, typically a consumer price index (CPI). When the general price level rises, each unit of curre ...
, but does not itself drive inflation, instead it generates curvature perturbations at late times after the
inflaton field
The inflaton field is a hypothetical scalar field that is conjectured to have driven cosmic inflation in the very early universe.
The field, originally postulated by Alan Guth, provides a mechanism by which a period of rapid expansion from 10 ...
has decayed and the decay products have redshifted away, when the curvaton is the dominant component of the energy density. It is used to generate a flat spectrum of CMB perturbations in models of inflation where the potential is otherwise too steep or in alternatives to inflation like the pre-Big Bang scenario.
The model was proposed by three groups shortly after one another in 2001:
Kari Enqvist
Kari-Pekka Enqvist (born February 16, 1954, in Lahti, Finland) is a professor of cosmology in the Department of Physical Sciences at the University of Helsinki. Enqvist was awarded his PhD in theoretical physics in 1983.
Enqvist is the chairman ...
and Martin S. Sloth (Sep, 2001),
David Wands
David Wands is professor of cosmology at the Institute of Cosmology and Gravitation, in the University of Portsmouth.
He was educated at Dr Challoner's Grammar School, Amersham, and Gonville and Caius College, Cambridge, where he read Natural S ...
and
David H. Lyth
Professor David Lyth (21 June 1940) is a researcher in particle cosmology at the University of Lancaster. He has published over 165 papers as well as two books on early universe cosmology and cosmological inflation.
Research
He is noted for his wo ...
(Oct, 2001), Takeo Moroi and Tomo Takahashi (Oct, 2001).
See also
*
Expansion of the universe
The expansion of the universe is the increase in proper length, distance between Gravitational binding energy, gravitationally unbound parts of the observable universe with time. It is an intrinsic and extrinsic properties (philosophy), intrins ...
*
Hubble's law
Hubble's law, also known as the Hubble–Lemaître law, is the observation in physical cosmology that galaxies are moving away from Earth at speeds proportional to their distance. In other words, the farther a galaxy is from the Earth, the faste ...
*
Big Bang
The Big Bang is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models based on the Big Bang concept explain a broad range of phenomena, including th ...
*
Cosmological constant
In cosmology, the cosmological constant (usually denoted by the Greek capital letter lambda: ), alternatively called Einstein's cosmological constant,
is a coefficient that Albert Einstein initially added to his field equations of general rel ...
*
Inflaton
The inflaton field is a hypothetical scalar field that is conjectured to have driven cosmic inflation in the very early universe.
The field, originally postulated by Alan Guth, provides a mechanism by which a period of rapid expansion from 1 ...
*
Cosmological perturbation theory
In physical cosmology, cosmological perturbation theory is the theory by which the ''evolution of structure'' is understood in the Big Bang model. Cosmological perturbation theory may be broken into two categories: Newtonian or general relativist ...
*
Structure formation
In physical cosmology, structure formation describes the creation of galaxies, galaxy clusters, and larger structures starting from small fluctuations in mass density resulting from processes that created matter. The universe, as is now known from ...
*
Kari Enqvist
Kari-Pekka Enqvist (born February 16, 1954, in Lahti, Finland) is a professor of cosmology in the Department of Physical Sciences at the University of Helsinki. Enqvist was awarded his PhD in theoretical physics in 1983.
Enqvist is the chairman ...
*
David Wands
David Wands is professor of cosmology at the Institute of Cosmology and Gravitation, in the University of Portsmouth.
He was educated at Dr Challoner's Grammar School, Amersham, and Gonville and Caius College, Cambridge, where he read Natural S ...
*
David H. Lyth
Professor David Lyth (21 June 1940) is a researcher in particle cosmology at the University of Lancaster. He has published over 165 papers as well as two books on early universe cosmology and cosmological inflation.
Research
He is noted for his wo ...
Notes
Physical cosmology
Inflation (cosmology)
Hypothetical elementary particles
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