no a person can not get ptsd from researching the 9/11 event ...the diagnostics specifically state in reference to the media....

Experiencing repeated or extreme exposure to aversive details of the traumatic event(s); this does not apply to exposure through media such as television, movies, or pictures....

in other words anything that has been publicized in some way.

in order to be diagnosed with PTSD a person must have some direct (witnessing or personally going through) or indirect (knowing a close family member or close friend has been through) the trauma.

this is just one out of 8 diagnostic criteria that must be met to be diagnosed with PTSD now.

thats not saying a person cant cause their self to have ....Anxiety ...symptoms. I know many people who search the internet and cause their self to have anxiety, nightmares over what they have read or seen.