عنوان البحث(Papers / Research Title)
Dark Matter and Dark Energy
الناشر \ المحرر \ الكاتب (Author / Editor / Publisher)
احمد محمود عبد اللطيف الخفاجي
Citation Information
احمد,محمود,عبد,اللطيف,الخفاجي ,Dark Matter and Dark Energy , Time 6/11/2011 3:58:59 PM : كلية العلوم
وصف الابستركت (Abstract)
ما هو أصل الكون؟ ومتى بدا؟ وما هو مصيره؟
الوصف الكامل (Full Abstract)
The beginning before 13.7 billion yeas
The Planck era was extremely brief—just 10-43 secondsDuring this period, all four forces of the universe—gravity, electromagnetic energy, and the weak and strong nuclear forces—were theoretically equal to one another, implying that there may have been just one unified force. The Planck era was extremely unstable, with the four forces quickly evolving into their current forms, starting with gravity and then the strong nuclear force (what binds protons and neutrons together in the nucleus of an atom), the weak nuclear force (associated with radioactive decay, it is some 100 times weaker than the strong force), and finally electromagnetic energy. It took some 200 million years for gravity to begin coalescing these free-floating atoms into the primordial gas out of which the first stars and galaxies would emerge. Over billions of years, such early stars and galaxies phased through their lifecycle, using up their nuclear fuel and collapsing in on themselves.The sun around which the earth and the solar system rotate is one of these later generation stars, formed roughly five billion years ago.
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