Equation 15 · From Origins to Frontier: A History of Stochastic Thermodynamics and Complex Systems
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Symbol k_B
is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
Symbol T
T is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
subscript
The lower label selects a particular version, component, or indexed member of the quantity. For example, x₀ and xₜ can be values at different positions.
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That same year, Shoichi Toyabe, Sagawa, Ueda, Eiro Muneyuki, and Masaki Sano built and ran the device, reporting “Experimental Demonstration of Information-to-Energy Conversion and Validation of the Generalized Jarzynski Equality” in Nature Physics [ 8 ] . Their apparatus used a single colloidal particle on a spiral-staircase-shaped potential created by a rotating electric field; real-time feedback, triggered by measuring which way the particle had diffused, allowed the particle to climb the staircase using only thermal fluctuations and the information gained by observation, extracting free energy in excess of the direct work performed on it and confirming the Sagawa-Ueda generalized…
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That same year, Shoichi Toyabe, Sagawa, Ueda, Eiro Muneyuki, and Masaki Sano built and ran the device, reporting “Experimental Demonstration of Information-to-Energy Conversion and Validation of the Generalized Jarzynski Equality” in Nature Physics [ 8 ] . Their apparatus used a single colloidal particle on a spiral-staircase-shaped potential created by a rotating electric field; real-time feedback, triggered by measuring which way the particle had diffused, allowed the particle to climb the staircase using only thermal fluctuations and the information gained by observation, extracting free energy in excess of the direct work performed on it and confirming the Sagawa-Ueda generalized equality quantitatively. Eighty-one years after Szilard’s paper, his single-particle information engine existed as hardware, not just as a page of algebra, and it ran close enough to the Szilard limit that its measured information-to-energy conversion could be directly compared to T 2 per bit.
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