Why Do Cans of Diet Coke Float and Coke Don't?

In any event, initially, this floating problem seems like something that breaks physics because both cans are the exact same size and contain exactly the same amount of liquid. Of course, anyone who’s ever taken a physics class at some point probably knows what makes a given object float in the first place, in the simplest possible sense, is that an object will float provided it displaces an amount of liquid (or sufficiently dense gas) that weighs more than itself.