Contemporary physics...a presentation of its basic principles

This book takes the reader from classical physics to the present situation or "contemporary physics" and shows how the laws of the conservation of matter and the conservation of energy are applied in physics, especially after it became known that matter converts to energy, and that energy has a mass that can be calculated from Einstein''s equation, and deals with new meanings of the concept Physics. Since many of the terms in this field enter the Arabic language for the first time, they have not settled in use. The translator has sought to use many terms and vocabulary without consensus on them. Perhaps their circulation will lead to their approval or modification for the better. This is a commendable attempt. Hopefully such terms will not be an obstacle in transmitting science to readers of Arabic.