01
Barrier 1 — Air Conduction
01 · Air masks everything.
At atmospheric pressure, air trapped in a micro-scale gap conducts heat so efficiently that it completely overwhelms any radiation-based signal. At our largest gap of 508 µm, air conduction exceeded radiation by 7 times. At our smallest gap of 8.5 µm, it exceeded radiation by 419 times.
Air-to-radiation ratio: 7× – 419× across all tested gaps
Our solution:
Reduce the air. Under partial vacuum (~38 Torr, roughly 5% of atmosphere),
the air-to-radiation ratio at 508 µm drops from 7:1 to 0.4:1 — radiation becomes dominant.
02
Barrier 2 — Mechanical Instability
02 · Gaps smaller than a human hair don't stay still.
A human hair is about 70 µm wide. We were trying to hold gaps as small as 8.5 µm — and keep them perfectly parallel. Our first design used screw clamping. Tilt at the micron scale means the gap varies enormously across the interface.
We rebuilt the entire apparatus around a different principle: position defined by geometry, not force.
Solution: Kinematic constraint — precision-machined guides define plate position
03
Barrier 3 — Environmental Drift
03 · The signal is smaller than the noise — unless you design around it.
Our thermoelectric sensors measure heat flux in millivolts. The rectification signal we were looking for was a fraction of a millivolt. Over a 9-hour overnight run, room temperature drifts.
We solved this with the ABBA bidirectional heating protocol and Allan deviation analysis.
ABBA + Allan deviation cancels 10–20× overestimation of precision
FALSE POSITIVE CALLOUT
We found a statistically significant result, and rejected it.
Midway through atmospheric testing, our through-gap metric produced η = 0.9883 —
a 1.17% apparent rectification signal with p = 0.0005. By conventional standards, that's significant.
Then we ran the first-principles analysis:
Heater temperature offset (steel vs glass)
4.4°C hotter
Predicted calibration artifact
1.2%
What we actually measured
1.17%
Match
within 0.03%
p = 0.0005 apparent signal → REJECTED via first-principles analysis
Statistical significance alone is not enough to claim a physical effect.
Barrier
Air conduction
Mechanical instability
Environmental drift
Measurement Impact
Masks radiation 7–419×
Gap variation ≈ signal noise
10–20× false precision
Our Solution
Partial vacuum (~38 Torr)
Kinematic constraint + Kapton shims
ABBA protocol + Allan deviation