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Equation 61 · Part 2 · A Horizon Is a Toll Booth, Not a Loophole

Symbol r_s

r→rs=2GM/c2r\to r_s=2GM/c^2
rsr_s

What this part means

rsr_s is part of the quantity the equation computes from the expression on the right.

Its job in the formula

rsr_s is part of the quantity the equation computes from the expression on the right.

The passage around this formula

As r→\to rsr_s=2GM/c2c^2 , f→\to0 and a(r)→\to∞\infty : holding station arbitrarily close to a horizon costs arbitrarily large continuous thrust, sourced from arbitrarily large continuous energy expenditure, which is exactly the situation Unruh’s original analysis and the long literature it produced treat as the flip side of a diverging local temperature for an accelerated or static near-horizon observer [ 9 , 12 ] .

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Sources cited in the article section

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