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%\usepackage{hyperref} 
\usepackage{makeidx}
\makeindex
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‎\setlatintextfont[Scale=1 ]{Times New Roman}‎
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\theoremstyle{definition}
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\begin{document}
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\chapter{ماده‌ی تاریک در کیهان شناسی}
‎ \newpage‎
‎\pagenumbering{arabic}