A Crack in the Line

Today I picked up the novel A Crack in the Line by Michael Lawrence at the library. I haven't started reading it yet, but i have been thinking about the description on the inside cover.

The mystery has begun Alaric It's been two years since his mother died in a terrible train crash, and Alaric's life continues to unravel. He and his father are barely on speaking terms, and Withern Rise, their Victorian mansion, is in shambles. Trapped at home during a blizzard, Alaric stumbles into a parallel world; a reality in which his mother is still alive. There's only one problem ... someone else is living his life. Naia Naia tries not to dwell on the horrible accident two years ago that nearly took her mother away. Now that life with her parents in Withern Rise has returned to normal, Naia thinks the worst is behind her. But during a freak snowstorm she's confronted by a stranger. Why does this boy look like her? Why does he have the same thoughts? The same memories? Who is he? Alaric's and Naia's discovery of each other sets off an electrifying chain of events. And as their lives - and lifelines - entwine, the two teenagers uncover a truth with the power to rearrange, or even erase, their very existence.

I mean, what if we really do have a parallel world? That would be so cool. Would we ever be able to find it even if we did? If it was like the parallel world in this book, would one of the world's be opposite from the other except for the personality of the one person, ourselves? And if we discovered our other body and our lives started to "entwine", would we be able to "rearrange, or even erase, our very existence"? This is like a chain that made me think there may be many alternate worlds, but how will we ever know the truth unless somehow, some miracle happens, and we do discover an alternate world?