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https://www.askamathematician.com/2013/01/qhow-do-lenses-that-concentrate-light-not-violate-the-second-law-of-thermodynamics-if-you-use-a-magnifying-glass-to-burn-ants-arent-you-making-a-point-hotter-than-the-ambient-temperature-without/ https://www.askamathematician.com/2013/01/qhow-do-lenses-tha... https://scienceblogs.com/builtonfacts/2010/05/27/solar-heat-thermodynamics-pt-2 https://scienceblogs.com/builtonfacts/2010/05/27/solar-heat-...