Invariance

-Galileo's invariance as OTL

Electrodynamic invariance

Liang's theory of gravity

-when French attempt to film earth from a satellite (Rocketry > ^31e0fe) fails because it "misses", inspires people to determine why

-though France keeps hush-hush about its intentions to spy on Germany

-soon afterwards, work begins on establishing a gravitational theory of invariance

-with Liang Jao-ming being man who does it