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Mohamad Reza Setare

Mohamad Reza Setare

Academic rank: Professor
ORCID:
Education: PhD.
ScopusId: 7003669033
Faculty: Faculty of Science
Address:
Phone: 08716660075

Research

Title
Emergence and expansion of cosmic space as due to M0-branes
Type
JournalPaper
Keywords
brane ; M- theory ; cosmic space
Year
2015
Journal EUROPEAN PHYSICAL JOURNAL C
DOI
Researchers Alireza Sepehri ، Mohamad Reza Setare ، Salvatore Capozziello

Abstract

Recently, Padmanabhan ( arXiv: 1206.4916 [hepth] ) discussed that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region causes the accelerated expansion of the universe. The main question arising is: what is the origin of this inequality between the surface degrees of freedom and the bulk degrees of freedom? We answer this question in M-theory. In our model, first M0-branes are compactified on one circle and N D0-branes are created. Then N D0-branes join each other, grow, and form one D5-branes. Next, the D5-brane is compactified on two circles and our universe’s D3-brane, two D1-branes and some extra energies are produced. After that, one of the D1-branes, which is closer to the universe’s brane, gives its energy into it, and this leads to an increase in the difference between the numbers of degrees of freedom and the occurring inflation era. With the disappearance of this D1-brane, the number of degrees of freedom of boundary surface and bulk region become equal and inflation ends. At this stage, extra energies that are produced due to the compactification cause an expansion of the universe and deceleration epoch. Finally, another D1-brane dissolves in our universe’s brane, leads to an inequality between degrees of freedom, and there occurs a new phase of acceleration.