Military conflict in which the contenders mobilize all of their civilian and military resources in order to obtain a complete victory. It is distinguished from the partial commitment of lives and resources in limited war. The modern concept of total war is traced to Carl von Clausewitz, who stressed the importance of crushing the adversary's forces in battle and described wars as tending constantly to escalate in violence toward a theoretical absolute. The classic 20th-century work is Erich Ludendorff's The Total War (1935). World Wars I and II are usually regarded as total wars. After World War II, especially during the Cold War, the prospect of an all-out nuclear war made the major powers reluctant to engage in full-scale international warfare or allow their client states to do so.
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Complete reflection of a ray of light in a medium such as water or glass, from the surrounding surfaces back into the medium. It occurs when the angle of incidence is greater than a certain limiting angle, called the critical angle. In general, it takes place at the boundary between two transparent media when a ray of light in a medium of higher index of refraction approaches another medium of lower index of refraction at more than the critical angle. At all angles less than the critical angle, both reflection and refraction occur. Total internal reflection is responsible for rainbows, atmospheric halos, the sparkle of a diamond, and the path of light through optical fibres.
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