KentuckyFC writes "Network theorists have always simulated the spread of information through the internet using the same models epidemiologists use to study the spread of disease. Now Chinese scientists say this isn't quite right--it's easy to infect everybody you meet with a disease but it's much harder to inform all your contacts of a particular piece of information. So they've redone the conventional network simulations assuming that people only ever transmit messages to a certain fraction of their friends. And their results throw up a surprise. In these models, there are always individuals or clusters of individuals who are unreachable. These people never receive the information and make up a kind of underclass who eke out an information-poor existence in a few dark corners of the network. That has implications for organizations aiming to spread ideas who will have to think more carefully about how to reach people in these dark corners. That includes marketers and advertisers hoping to sell products and services but also agencies hoping to spread different kinds of messages such as safety-related information. It also raises the interesting prospect of individuals seeking out the dark corners of the internet, perhaps to preserve their privacy or perhaps for more nefarious reasons."