Editing Cosmic inflation (section)

===Reheating===
Inflation is a period of supercooled expansion, when the temperature drops by a factor of 100,000 or so. (The exact drop is model-dependent, but in the first models it was typically from {{10^|27}}&nbsp;K down to {{10^|22}}&nbsp;K.<ref name=Guth-1982-NuffWksh>
{{cite conference
 |last=Guth |first=Alan
 |date=21 June – 9 July 1982
 |title=Phase transitions in the very early universe
 |editor1-last=Gibbons |editor1-first=G.W.
 |editor2-last=Hawking |editor2-first=S.  |editor2-link=Stephen Hawking
 |editor3-last=Siklos  |editor3-first=S.T.C. 
 |edition=illustrated, reprint
 |conference=The Very Early Universe: Proceedings of the Nuffield Workshop, [[Cambridge University|Cambridge]]
 |place=Cambridge, UK
 |publisher=[[Cambridge University Press|Cambridge U.P.]]
 |publication-date=29 March 1985
 |orig-year=1st ed. 1983
 |isbn=9780521316774
 |oclc=14137101
}} {{ISBN|0-521-31677-4}}
</ref>) This relatively low temperature is maintained during the inflationary phase. When inflation ends, the temperature returns to the pre-inflationary temperature; this is called ''reheating'' or thermalization because the large potential energy of the inflaton field decays into particles and fills the Universe with [[Standard Model]] particles, including [[electromagnetic radiation]], starting the [[radiation-dominated era|radiation dominated phase]] of the Universe. Because the nature of the inflaton field is not known, this process is still poorly understood, although it is believed to take place through a [[parametric oscillator|parametric resonance]].<ref>
See {{harvp|Kolb|Turner|1988}} or {{harvp|Mukhanov|2005}}.
</ref><ref>
{{cite journal
 |first1=Lev     |last1=Kofman
 |first2=Andrei  |last2=Linde
 |first3=Alexei  |last3=Starobinsky
 |year=1994
 |title=Reheating after inflation
 |journal=[[Physical Review Letters]]
 |volume=73  |issue=5  |pages=3195–3198
 |bibcode=1986CQGra...3..811K  |pmid=10057315
 |arxiv=hep-th/9405187  |s2cid=250890807
 |doi=10.1088/0264-9381/3/5/011
}}
</ref>