Do you know a SCIENTIFIC THEORY that was falsified years later?

On which bit?

Phlogiston, the theory of what caused fire and rust before oxygen was discovered.

The fact that GR, not QM needs to be modified. I think (not exactly sure on the details) that twistor theory is his attempt to find a geometric view of QM.

it's pretty long-winded and i'm not sure how i'd go about drawing it on here (it shoud be in your physics book). But simply put - waves diffract when put through narrow gaps. double slit interference is when you put it through 2 narrow gaps. the light projected through the gaps are shone onto a screen. now where the waves from the 2 gaps cause a trough and a peak to meet destructive interference happens causing a black colour to appear on the screen. and where a trough and trough/ peak or peak meet constructive interference happens so we see the colour of the light on the screen. by putting the light through 2 slits we can see a pattern of black-colour-black-colour which shows that the light is interefering with itself the way waves do.