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Equation 93 · Part 3 · A Horizon Is a Toll Booth, Not a Loophole

subscript

kBTln⁡2k_BT\ln2
subscript

What this part means

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.

Its job in the formula

A subscript distinguishes a version, component, step, or member of a quantity. It does not automatically mean multiplication.

The passage around this formula

Everything above concerns N⊥N_\perp[Γ\Gamma] , a bound on unitary orthogonalizations, which cost no minimum heat in principle: a sequence of reversible gates can in principle run adiabatically, with no thermodynamic floor at all beyond the ordinary Levitin-Toffoli rate. Reading out a result, however, generally requires erasing or resetting some register, and that step is bound by a different and independent piece of physics, Landauer’s principle: erasing one bit at local temperature T costs at least kBk_BTln⁡\ln2 of dissipated heat [ 6 ] , made precise with finite-size corrections by Reeb and Wolf [ 7 ] . This bound does not care about horizons at all except through whatever value T takes locally —…

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Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

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Sources cited in the surrounding passage

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