Oscillating scalar fields in extended quintessence
نویسندگان
چکیده
منابع مشابه
Quintessence without scalar fields
The issues of quintessence and cosmic acceleration can be discussed in the framework of theories which do not include necessarily scalar fields. It is possible to define pressure and energy density for new components considering effective theories derived from fundamental physics like the extended theories of gravity or simply generalizing the state equation of matter. Exact accelerated expandi...
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Observations indicate that dark energy constitutes a substantial fraction of our Universe [1, 2, 3, 4, 5]. The range of possible candidates includes a cosmological constant and more flexible some form of dark energy with time dependent equation of state, called quintessence [6]. Commonly, realizations of quintessence scenarios feature a light scalar field [7, 8, 9]. The evolution of the scalar ...
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ژورنال
عنوان ژورنال: Physical Review D
سال: 2018
ISSN: 2470-0010,2470-0029
DOI: 10.1103/physrevd.97.023530