So, an over-view of Arther and Ayşe’s double or 2 slit experiment in association with the T’s is something like this…

… 2 slits in the first wall. Fire particles at it. Some go through and hit the back wall to create 2 stripes of impact impressions.

So, particles pass through the slits and form 2 stripes on the back wall screen. This is called particle behaviour.

For further explanation,

here are three different 2 slit experiment presentations:

https://www.youtube.com/watch?v=hB_2Qd5xNvE

https://www.youtube.com/watch?v=A9tKncAdlHQ

https://www.youtube.com/watch?v=DfPeprQ7oGc

p.189