Hacker News
The Failure of the Thermodynamics of Computation (2010)
svnt
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2012 — Bérut et al. (Nature) — They used a single colloidal silica bead (2 μm) trapped in a double-well potential created by a focused laser. By modulating the potential to erase the bit, they showed that mean dissipated heat saturates at the Landauer bound (k_B T ln 2) in the limit of long erasure cycles.
https://www.physics.rutgers.edu/~morozov/677_f2017/Physics_6...
2014 — Jun et al. (PRL) — A higher-precision follow-up using 200 nm fluorescent particles in an electrokinetic feedback trap. Same basic physics, tighter error bars.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4795654/
2016 — Hong et al. (Science Advances) — First test on actual digital memory hardware. Used arrays of sub-100 nm single-domain Permalloy nanomagnets and measured energy dissipation during adiabatic bit erasure using magneto-optic Kerr effect magnetometry. The measured dissipation was consistent with the Landauer limit within 2 standard deviations using the actual the basis of magnetic storage.
https://www.science.org/doi/10.1126/sciadv.1501492
2018 — Guadenzi et al. (Nature Physics) — Opens with:
The erasure of a bit of information is an irreversible operation whose minimal entropy production of kB ln 2 is set by the Landauer limit1. This limit has been verified in a variety of classical systems, including particles in traps2,3 and nanomagnets4. Here, we extend it to the quantum realm by using a crystal of molecular nanomagnets as a quantum spin memory and showing that its erasure is still governed by the Landauer principle.
https://www.nature.com/articles/s41567-018-0070-7
The Landauer limit is not conjecture.
svantana
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smitty1e
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The objection seems to be the "free lunch" assumptions being made about shrinkability.
"What Is TANSTAAFL?" https://youtu.be/ZrZUe7R44eA?si=oK2H1L9ha1zQhDOh
debatem1
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ogogmad
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I am pretty ignorant of this field.