Symbol Δ r
Δ r is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
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[ 11 ] . Setting equal to a demanding but realistic dilution-refrigerator base temperature of 10\, and solving for the required clearance gives r2.810^{-14}\, — a few nuclear radii from the horizon. For a supermassive hole, in other words, the ambient Hawking bath stays colder than any laboratory cryostat until the processor is closer to the horizon than an atomic nucleus, twenty-odd orders of magnitude closer than the point at which the support-acceleration bill already becomes unpayable. Cooling is a genuine, non-negotiable line item — it is what ties this construction to horizon thermodynamics at all — but for this mass scale it is not…
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Symbol m
m is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.
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Equation 76 · Evolutionary Physics
A Horizon Is a Toll Booth, Not a Loophole
This mathematical expression combines the displayed quantities; its precise role follows from the surrounding article text.
[ 11 ] . Setting equal to a demanding but realistic dilution-refrigerator base temperature of 10\, and solving for the required clearance gives r2.810^{-14}\, — a few nuclear radii from the horizon. For a supermassive hole, in other words, the ambient Hawking bath stays colder than any laboratory cryostat until the processor is closer to the horizon than an atomic nucleus, twenty-odd orders of magnitude closer than the point at which the support-acceleration bill already becomes unpayable. Cooling is a genuine, non-negotiable line item — it is what ties this construction to horizon thermodynamics at all — but for this mass scale it is not…
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