Healthcare · The edge of physics
Thoracic/bladder fluid-shift trending (NeRF tissue-water imaging)
People wish WiFi could watch fluid building up inside the lungs or bladder.
Not claimed
We publish what we will not claim — that is how you can trust the rest.
Why the physics says no
WiFi waves only reach a centimetre or two into the human body before fading away, so changes deep inside the chest or bladder are simply too faint to read. We would rather tell you that than pretend.
In the physics: Body water content dominates tissue permittivity (water eps_r~80); accumulating lung/interstitial fluid or a filling bladder raises the localized eps_r and alters through-body path attenuation and scattering at that anatomical delay bin, exactly what the field-reconstruction stage is built to map.
Reviewer's verdict: Penetration depth in high-water tissue at 2.4/5GHz is only ~1-3cm; after two-way tissue loss, deep thoracic/bladder fluid changes are far below the CSI noise floor. Commodity WiFi cannot image internal organ water content - the claimed internal-eps_r observable does not survive body attenuation.