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There isn't exactly a mathematical relationship, but there is a physical one. It is the gravitational compression that causes the increase in temperature in the core of the gas cloud that becomes a star. When the temperature reaches a critical value (in the millions of Kelvin range), hydrogen fusion can occur. This is because the temperature is great enough ...


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I wonder if your number 48% comes from the typical Carnot efficiency of a heat engine - see for example a detailed description at http://www.visionofearth.org/industry/fusion/how-do-we-turn-nuclear-fusion-energy-into-electricity/ When you want to use heat to create electricity, you typically convert the heat into motion (for example by rotating a turbine, ...


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The motivation for pursuing fusion is clear, but there are currently several main physics and engineering challenges: Confinement time: An operational reactor requires a long energy confinement time, $\tau_E$. An empirical scaling law for confinement time has been found to depend on the size of the tokamak as $\tau_E \propto R^{2.04} a^{1.04}$, where $R$ ...


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Elements heavier than iron are produced mainly by neutron-capture inside stars, although there are other more minor contributors (cosmic ray spallation, radioactive decay or even the collision of neutron stars). Neutron capture can occur rapidly (the r-process) and occurs mostly inside supernova explosions. The free neutrons are created by electron capture ...


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Very high temperature, on the order of 10 keV, is needed for fusion reactions to start to happen at appreciable rates. However, in magnetic fusion devices (tokamak, stellarator) the transport of heat across the plasma (due to plasma turbulence) causes heat losses. Making the system larger allows increasing the heating power (due to fusion reactions, plasma ...


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I personally doubt that the Compact Fusion Reactor as presented by Lockheed Martin last week can work, but I haven't seen enough information to be certain. And to some extent, you never know until you try. (As I understand it, they only have a very early prototype, I mean try as in a full scale prototype.) What I think I can say with certainty, is that it ...


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The comments basically answer the question. Another answer is found on HyperPhysics by Rod Nave: While magnetic confinement seeks to extend the time that ions spend close to each other in order to facilitate fusion, the inertial confinement strategy seeks to fuse nuclei so fast that they don't have time to move apart. Directed onto a tiny ...


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Oh, but we do! I'm assuming you mean using the fields to simply collide particles with each other, right? Then that's already being done. For example, take this neat little machine: http://en.wikipedia.org/wiki/Fusor This one runs on the exact same principle you described (though I'm not quite familiar with the inner workings of the LHC). For energy ...


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The energy per proton at the LHC is much larger than what is needed for fusion, protons break up into their constituents easily at this energy and fly away after they interact. In a fusion reactor, one wants the particles to stay within the reactor volume such that the released energy can be transferred to other deuterium/tritium nuclei which then can ...



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