A new game named Quantum Conundrum is making its debut at PAX 2011, and Valve fans may want to take note. The first-person physics-based puzzle game comes from the mind of Kim Swift, whose student project Narbacular Drop became the building blocks for the original Portal. Swift left Valve to head up a project at Airtight Games, and Quantum Conundrum definitely shows its roots.

GameSpot previews the title, which takes place in an ostentatious mansion and has you solve puzzles with an Interdimensional Shift Device, or IDS. You can shift between dimensions, which is the primary conceit of the game's puzzles. You place rifts to access items in other dimensions, like the "fluffy" dimension that makes a too-heavy safe much easier to carry. You'll also run into lasers, a giant robot-puppy named Dolli, and other realities like the slow-mo dimension and reverse-gravity dimension -- the effects of which should be fairly obvious.

The story is a quirky romp through the mansion as a kid dropped off at the house of his rich uncle, Professor Fitz Quadwrangle. After an explosion rocks the mansion, Fits goes missing and the kid takes up the IDS to find him.

The game is said to last 4-6 hours, and will be a downloadable title on PC, PlayStation Network, and Xbox Live Arcade in early 2012.