I haven't seen anyone mention the EPR (Einstein Podolski Rosen) paper. It's one of the most influential papers to modern physics, having essentially laid out an

I haven't seen anyone mention the EPR (Einstein Podolski Rosen) paper. It's one of the most influential papers to modern physics, having essentially laid out an opposition to how quantum theory works. Leading to Bell's inequalities and their later experimental verification (which essentially proved the EPR argument "wrong"). It is very clearly written does not contain any maths and can be understood by a non expert (IMO) definitely worth a read.