Daniel look's through journal, talks to Desmond

Daniel Faraday flips through his journal about the island. I've included screens of each of the pages we see that mostly have formulas on them. We can see the page that says "If anything goes wrong, Desmond Hume will be constant" that we saw in "The Constant" last season. Also readable is the phrase "Solving Einstein's Equation." Daniel sees something in his journal that we do no see, but it makes him go back to the Swan station door and knock. Desmond emerges with a gun in the yellow suit like the one Kelvin wore. I think we can assume that since Desmond is wearing the suit, the time that they are in is before Desmond killed Kelvin so it's before flight 815 crashed on the island. Also, Desmond says that he's heard the knocking for 20 minutes, which means he could hear Sawyer knocking, but couldn't go outside to meet Sawyer because that would break the rules. Once again, confusing yet intriguing.

Daniel tells Desmond that he's special and that he needs to go to Oxford and find his mom. Why and how is Desmond special. Why can Daniel communicate with him in the past and have him remember it in the present? Alos, who is Daniel's mom and what does she know about the island? Daniel skips in time again before we hear her name. I have my theory about how she is, but I'd love to hear yours.