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The Dark Energy Regulated by Emergent Conformal Symmetry

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 نشر من قبل Yongsung Yoon
 تاريخ النشر 2013
  مجال البحث فيزياء
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 تأليف Yongsung Yoon




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We have found a mechanism which regulates the dark energy in our universe. With an emergent conformal symmetry, the dark energy density is regulated to the order of a conformal anomaly parameter in the conformally coupled gravity. In the late time cosmological evolution, we have obtained a set of exact cosmological equations which deviate from the Friedmann equations significantly. Based on the recent observational cosmic expansion data, it is shown that the dark energy density is about 1/4 of the matter density at present, which is quite smaller than determined by General Relativity. The jerk parameter at present is also determined as a definite value 0.47.



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