Abstract: | The wide diversity of cosmic explosion arise from a variety of complex physical phenomena. Each one of these cosmic fireworks, be it supernovae, gamma ray burst, stellar collisions or tidal disruptions is different in nature, but many of them also share many similarities. In recent years the field of cosmic explosions began to be filled with a zoo of peculiar explosions ranging in orders of magnitude in brightness and time-length. I will discuss the strongly debated progenitors of such cosmic explosions, the main processes involved in their actual production, their major implications for the evolution of the universe, and I will touch upon the many open questions which they raise. In particular I will explain how do the regular seemingly delicate but shining life of stars eventually lead to their violent explosive death; how close symbiotic relations between companion stars which exchange materials between them end up in a blasting breakout of a ball of fire. If time permit, I will explore the realm of stellar dynamics where stars can clash and collide in small chaotic systems and in dense stellar clusters, and explain how lighter stars are shredded by more massive ones, or even by monstrous supermassive black holes in galactic nuclei. Beside their magnificent role in lighting up our night sky, cosmic explosions have major implications for the overall evolution of the universe and our understanding of it, and play a key-role in the build-up of the basic elements needed for life. I will briefly discuss how they shape the environments of galaxies through a network of feedback processes between star formation and stellar death, and I'll review how explosive thermonuclear burning in these explosion synthesize the heavy elements which compose most of Earth and and thriving living environment in which we live today. |