It doesn’t.
I downloaded both the Obama certificate and your photoshop. The distortion around the letters in yours is very different from that in the Obama certificate.
The distortion in your photoshop is much closer to the samples I created on my own machine using Appleworks Paint and typing on a textured background. The distorion in the Obama certificate is much closer to that in the scanned jpg of a university transcript I zoomed in on.
Then you are obviously a troll sent here form the Obama campaign.
/s