C-0007 Verified HIGH certainty
The quantum inequality constrains the Alcubierre bubble wall to at most about 10^2 v_b Planck lengths, roughly 1.6e-33 m at light speed — about 10^-18 of a proton radius.
Standing peer reviewed contested · bound · TRL 1 Assumes the Ford-Roman quantum inequality for a free massless scalar field in four-dimensional Minkowski spacetime, applied on a scale where the region can be treated as locally flat; a single quantised free scalar field; the bound is not established for arbitrary matter content; the piecewise-linear shape function S-0007 uses, whose slope is 1/Delta across the whole wall; the sampling-time choice t_0 = alpha * 2 Delta / (sqrt(3) v_b) with alpha << 1 Stops applying matter content or field states to which the Ford-Roman inequality has not been extended, and regimes where the local-flatness approximation used to import the flat-space inequality fails Computed in compute/quantum_inequality.py
What it rests on
E-0013 · S-0007 — The unphysical nature of "Warp Drive" · equation
…eglect the term involving 1-f(rho) to find Now as an example, if we let alpha = 1/10, then \Delta \leq 10^2 v_b L_{Planck} , where is the Planck length. Thus, unless v_b is extremely large, the wall thickness cannot…
EXACT · re-found in source
Attacks run against it
X-0016 SURVIVED unstated assumption · by straz
Attacked the coefficient: the 10^2 in Delta <= 10^2 v_b L_Planck is not a constant of nature. S-0007's own eq. 19 introduces the sampling-time parameter alpha with 0 < alpha << 1, and eq. 21 (E-0029, cited by hash) gives Delta <= (3/4)sqrt(3/pi) v_b/alpha^2 = 0.733/alpha^2 — the published 10^2 is alpha = 0.1. Swept alpha: at 0.01, a hundred-fold weaker sampling assumption, the bound loosens to ~7300 L_P and the 100 m bubble still requires 4.7e18 galaxy masses. The coefficient moves by two orders; the verdict moves by two orders and remains eighteen orders beyond absurd. The claim's wording ('at most about 10^2') plus its regime, which carries the sampling-time choice as an assumption, survive.