. >> and i'm scott shafer.tonight's show, a look back at the bay area's past, present and a glimpse of its future. we begin with an event that happened 100 years ago, the 1915 world's fair. as joshua johnson shows us, it helped transform san francisco into the kozcosmopolitan center that it is today. >> they called it the jewel city. it rose from the mud flats of san francisco's waterfront. a cosmopolitan wonderland built to last just ten months. one of the only vestiges of this lost city is this building, the palace of fine arts. but in 1915 this was just one of many grand palaces that lined the avenues of a 635-acre mini metropolis constructed to host the world's fair in the area known today as the marina district. the fair drew some 19 million people, mostly for the thrill of exploring displays and demonstrations that highlighted the progress of industry, technology, and culture over the centuries. >> if you pushed through the turnstiles, you'd find yourself directly in front of a 435-foot-tall stepped tower

scott shafer is here to discuss those questions with a former 49er a high school football coach, andinvestigative reporter with espn. >> joining me now to discuss football's concussion crisis are espn sportswriter mark fainaru-wada. he's co-author of "league of denial denial," which exposed the nfl's efforts to deny the long-term impacts of concussions. dwight hicks, a former all-pro defensive player who helped the san francisco 49ers win two super bowls. dwight is starring in a new play at the berkeley rep called "xs and os: a football love story." and patrick walsh, head football coach at serra high school. he forfeited a consolation game last month rather than risk injuries to his players. gentlemen, welcome all of you. >> thank you. >> mark, let me begin with you. the nfl said this week that concussions were down 25% this week -- this year compared to last year. does that mean, do you think, that the nfl's doing a better job of protecting its players? >> well, i'll say this at the start. i think my brother and i, we did the work together at espn, you know, we did a story a couple

. >> and i'm scott shafer.tonight's show, a look back at the bay area's past, present and a glimpse of its future. we begin with an event that happened 100 years ago, the 1915 world's fair. as joshua johnson shows us, it helped transform san francisco into the k

scott shafer is with computer scientist aaron schulman. >> aaron schulman welcome. >> thank you. >> inayman's terms tell us what you and your team discovered. >> so our smartphones today are filled with a lot of sensors. for instance a compass and gyroscope, et cetera. and what's interesting is most of those sensors require some sort of permission from the application that's using them. so if you download an application it will say hey i need the compass and that might reveal your location. but there's one sensor in particular that doesn't actually need that and it's sort of a little-talked about sensor which is the power sensor. which tracks the power consumption of your phone over time. >> so these apps potentially can access that? >> that's right. yeah. any app actually in the android store can access that. and that power sensor is a bit troubling, or can be because it might reveal something about your location. so for instance, when you're driving down a road, you're moving closer and farther away from cell towers. and the closer you are to a cell tower, the less power your phone c

scott shafer takes it from here. shafer: new and evolving surveillance technology -- what does it mean for police, prosecutors, and law-abiding citizens worried about their privacy? joining me to discuss the implications are mike sena, director of the northern california regional intelligence center david greene senior staff attorney at the electronic frontier foundation and jennifer granick civil liberties director at the stanford center for internet and society. well, let me begin with you, jennifer. we heard that sheriff's deputy from los angeles saying we're already being on-camera everywhere with atms and red-light cameras, fastrak. so what's the big deal? how is this different? granick: what's different is whether all that information is aggregated and one party -- in this case, the government -- can get ahold of all of that because it means that they know so much about us that was really something that was never recorded before or even was just recorded for specific purposes, and now it can be used for more ge