My question concerns PhD applications that are handled on a departmental level by graduate admissions committees, as is the case in the US, Canada and a few other places. Further, I am interested mainly in STEM fields, with a particular focus on engineering applications.
I wish to know if graduate admissions committees look at any information that may be available about the applicant, beyond what is provided in the application itself. For instance, if an applicant's CV lists a couple of papers (and maybe even provides arXiv links to those publications), would the committee go out of their way to take a brief look at the papers (if not otherwise submitted by the applicant)? How would this change if the paper has been peer-reviewed or not?
What about other materials that an applicant may have provided? If an applicant's webpage is listed on their CV, would the committee take a look at it? More generally, what about information that the applicant may not have even provided? Would a committee ever feel the need to independently go out of their way to obtain more information by, say, searching Google, or social media, or a LinkedIn profile? Is this even "ethical"?