[HN Gopher] Landauer's Principle ___________________________________________________________________ Landauer's Principle Author : layer8 Score : 25 points Date : 2023-05-27 19:04 UTC (1 days ago) (HTM) web link (en.wikipedia.org) (TXT) w3m dump (en.wikipedia.org) | sgdpk wrote: | Inspired by this, in my PhD we actually used a quantum computer | to do classical logic to investigate if that can lead to energy | savings [1]. Quantum machines are (in principle) reversible, so | they may avoid Landauer's principle. | | However, there are subtle energy costs that you can hit before | getting to Landauer's. The most interesting to me is that the | qubits can become entangled with the wires that control them! | This reduces the quality of information, and one way around it is | to use a lot of energy [2]. | | [1] https://arxiv.org/abs/2210.10470 | | [2] | https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.89... | sneak wrote: | If I understand this correctly, this puts an upper bound on the | computational ability of a Dyson sphere surrounding a star. | _a_a_a_ wrote: | dyson spheres compute? | icegreentea2 wrote: | They don't have to. You can interpret the original comment as | "puts an upper bound on the computational ability of a Dyson | sphere if it dedicated all captured energy to computation". | surprisetalk wrote: | ELI5: there's a lower bound on the physical heat required to | erase one bit of information | | It's cool because it creates a relation between pure math | (information) and physics (entropy). | | Maxwell's Daemon is useful context. In short, it's a thought | experiment about trying to "cheat" 2nd law of thermodynamics, and | Landauer's Principle pops up as a computational speed limit of | sorts. | | [1] https://en.wikipedia.org/wiki/Maxwell%27s_demon | avmich wrote: | How reversible computing is related to it? | cleansingfire wrote: | Reversible computing cannot lose information or energy. No | dissipation allowed. | williamjackson wrote: | As a kid I always wondered where the name "Maxwell's Maniac" | came from. | | https://gamicus.fandom.com/wiki/Maxwell%27s_Maniac ___________________________________________________________________ (page generated 2023-05-28 23:00 UTC)