Efficiency
In nuclear reactions, typically only a small fraction of the total mass-energy is converted into heat, light, radiation and motion, into a form which can be used. When an atom fissions, it loses only about 0.1% of its mass, and in a bomb or reactor not all the atoms can fission. In a fission based atomic bomb, the efficiency Nuclear weapon designs are physical, chemical, and engineering arrangements that cause the physics package of a nuclear weapon to detonate. There are three basic design types. In all three, the explosive energy of deployed devices has been derived primarily from nuclear fission, not fusion is only 40%, so only 40% of the fissionable atoms actually fission, and only 0.04% of the total mass appears as energy in the end. In nuclear fusion, more of the mass is released as usable energy, roughly 0.3%. But in a fusion bomb (see nuclear weapon yield The explosive yield of a nuclear weapon is the amount of energy that is discharged when a nuclear weapon is detonated, expressed usually in the equivalent mass of trinitrotoluene , either in kilotons (thousands of tons of TNT) or megatons (millions of tons of TNT), but sometimes also in terajoules (1 kiloton of TNT = 4.184 TJ). Because the precise), the bomb mass is partly casing and non-reacting components, so that again only about 0.03% of the total mass is released as usable energy.
In theory, it should be possible to convert all the mass in matter into heat and light, but none of the theoretically known methods are practical. One way to convert all rest-mass into usable energy is to annihilate matter with antimatter In particle physics, antimatter is the extension of the concept of the antiparticle to matter, where antimatter is composed of antiparticles in the same way that normal matter is composed of particles. For example, an antielectron and an antiproton (a proton with a negative charge) could form an antihydrogen atom in the same way that an electron. But antimatter is rare in our universe The baryon asymmetry problem in physics refers to the apparent fact that there is an imbalance in baryonic matter and antibaryonic matter in the universe. Neither the standard model of particle physics, nor the theory of general relativity provide an obvious explanation for why this should be so; and it is a natural assumption that the universe be, and must be made first. Making the antimatter requires more energy than would be released.
Since most of the mass of ordinary objects is in protons and neutrons, in order to convert all the mass in ordinary matter to useful energy, the protons and neutrons must be converted to lighter particles. In the standard model of particle physics The Standard Model of particle physics is a theory of three of the four known fundamental interactions and the elementary particles that take part in these interactions. These particles make up all visible matter in the universe. The standard model is a gauge theory of the electroweak and strong interactions with the gauge group SU×SU(2)×U(1), the number of protons plus neutrons In particle physics, the baryon number is an approximate conserved quantum number of a system. It is defined as: is nearly exactly conserved. Still, Gerardus 't Hooft Gerardus 't Hooft (born July 5, 1946, Den Helder) is a professor in theoretical physics at Utrecht University, the Netherlands. He shared the 1999 Nobel Prize in Physics with Martinus J. G. Veltman "for elucidating the quantum structure of electroweak interactions". Asteroid 9491 Thooft is named in his honor; he has written a showed that there is a process which will convert protons and neutrons to antielectrons and neutrinos.[17] This is the weak SU(2) instanton An instanton or pseudoparticle is a notion appearing in theoretical and mathematical physics. Mathematically, a Yang-Mills instanton is a self-dual or anti-self-dual connection in a principal bundle over a four-dimensional Riemannian manifold that plays the role of physical space-time in nonabelian gauge theory. Instantons are topologically proposed by Belavin Polyakov Schwarz and Tyupkin.[18] This process, can in principle convert all the mass of matter into neutrinos and usable energy, but it is normally extraordinarily slow. Later it became clear that this process will happen at a fast rate at very high temperatures,[19] since then instanton-like configurations will be copiously produced from thermal fluctuations Statistical mechanics is the application of probability theory, which includes mathematical tools for dealing with large populations, to the field of mechanics, which is concerned with the motion of particles or objects when subjected to a force. It provides a framework for relating the microscopic properties of individual atoms and molecules to. The temperature required is so high that it would only have been reached shortly after the big bang The Big Bang is the cosmological model of the initial conditions and subsequent development of the universe that is supported by the most comprehensive and accurate explanations from current scientific evidence and observation. As used by cosmologists, the term Big Bang generally refers to the idea that the universe has expanded from a primordial.
Many extensions of the standard model contain magnetic monopoles, and in some models of grand unification Thus far, physicists have been able to merge electromagnetism and the weak nuclear force into the electroweak force, and work is being done to merge electroweak and quantum chromodynamics into a QCD-electroweak interaction sometimes called the electrostrong force. Beyond grand unification, there is also speculation that it may be possible to merge, these monopoles catalyze proton decay, a process known as the Callan-Rubakov effect.[20] This process would be an efficient mass-energy conversion at ordinary temperatures, but it requires making monopoles and anti-monopoles first. The energy required to produce monopoles is believed to be enormous, but magnetic charge is conserved, so that the lightest monopole is stable. All these properties are deduced in theoretical models--- magnetic monopoles have never been observed, nor have they been produced in any experiment so far.
The third known method of total mass–energy conversion is using gravity, specifically black holes. Stephen Hawking Stephen William Hawking, CH, CBE, FRS, FRSA is a British theoretical physicist. Hawking is the Lucasian Professor of Mathematics at the University of Cambridge (but intends to retire from this post in 2009), a Fellow of Gonville and Caius College, Cambridge and the distinguished research chair at Waterloo's Perimeter Institute for Theoretical theorized[21] that black holes radiate thermally with no regard to how they are formed. So it is theoretically possible to throw matter into a black hole and use the emitted heat to generate power. According to the theory of Hawking radiation Hawking radiation is a thermal radiation with a black body spectrum predicted to be emitted by black holes due to quantum effects. It is named after the physicist Stephen Hawking who provided the theoretical argument for its existence in 1974, and sometimes also after the physicist Jacob Bekenstein who predicted that black holes should have a, however, the black hole used will radiate at a higher rate the smaller it is, producing usable powers at only small black hole masses, where usable may for example be something greater than the local background radiation. It is also worth noting that the ambient irradiated power would change with the mass of the black hole, increasing as the mass of the black hole decreases, or decreasing as the mass increases, at a rate where power is proportional to the inverse square of the mass. In a "practical" scenario, mass and energy could be dumped into the black hole to regulate this growth, or keep its size, and thus power output, near constant.
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