Someone might see it, someone might not. Paper does not biodegrade in an anaerobic land fill and indeed archaeologists dig up old latrines looking for papers such as newspapers tossed in. It's unlikely that anyone would look for it and therefore it's unlikely to ever be seen but it will last far longer than you will.

no ones going to go through the garbage, it gets put into a big hole in the middle of no where.

It's buried-(If you don't want the "living world" to see your art, 'destroy it in pieces' & you'll be fine.)

Eventually it will decinigrate overtime unless it gets burned first. It depends on the trash place

No, it gets incinerated or dumped in a landfill where it will naturally biodegrade with time.

I'm an artist and I accidentally threw away "sensitive material" and don't want anyone to see what I've been working on (nothing bad, I just don't want my ideas stollen). Anyway, it's in the garbage truck gone forever. So what exactly happens to thrown away paper? Do people look at it?