There is a bug in Skyrim that makes it impossible to defeat Alduin when you encounter him. This bug has existed for a while, but in case you are unaware of how to get around it, here are a few tips to help fix this glitch.
Here is the live feed from the 2013 Consumer Electronics Show (CES) presented by the Tech Podcast Network (TPN), which we are affiliated with. CES 2013 begins January 8th in Las Vegas, NV. Watch interviews and see various vendors from the show here.