Is there any research that shows this? I’m not aware of any. In fact there are social reasons people might stay up late. It is a mistake to ignore that.
They had this discussion in Iceland recently (which is on permanent DST; and with heavy population centers way north of Alaskan population centers) and health officials were pretty keen on moving to standard time precisely because teenagers have a hard time waking up so often before sunrise. Yes a big part of the year will always be before sunrise, however on standard that part is shorter.
Yes, a lot. It's well summarized here:
This research would need to show that blinds and artificial blue light would be sufficient to replace natural sunlight for setting the sleep rhythm to a healthy level. The existence of flux actually suggests the opposite is true, and people need software to prevent artificial blue light from disrupting the sleep rhythm.
So because we _can_ disregard the sun, we should? I have lights in my home, but the sun still shines in the windows in the morning and on my head while I walk to work. I'd rather have sane policy than worry about always having a portable SAD light available in the winter mornings.
And kids have been going to school in the dark for a long time already. Talk to the Alaskans who go to school in the dark for a lot of the year. If anything, this would push people to move to a year round school schedule so we can take a longer winter break during the darkest part of the year.