demonstration using the original Chris Wanstrath's PJAX in PHP
important part i found was using
($_SERVER["HTTP_X_PJAX"])pjax loads HTML from your server into the current page without a full reload. It's ajax with real permalinks, page titles, and a working back button that fully degrades.
pjax enhances the browsing experience - nothing more.
You can find the original demo on http://pjax.heroku.com/