Howling:Interfering With Personal Timeline

So it's stated many times by The Doctor (The most glaring and recent example being the episode Fathers' Day in the original reboot) that interfering with one's own personal timeline will have disastrous consequences, cancel out history, et cetera. This is supposedly supported by The Eleventh Doctor in Big Band/The Pandorica Opens, when the two versions of the doctor's sonic screwdriver spark when held near each other due to "temporal friction"; i.e., the paradox of two identical objects being at the same point in space and time, but at different points on the object's timeline. So why is it that, when Rose touched the other version of herself in Fathers' Day, a great catastrophe occurred, but the Doctor is visibly seen to embrace his past/future self, exchange words, and all the rest when he uses the vortex manipulator to sneak away and wire up the Pandorica without the timeline negating like it did prior?110.175.4.178 12:10, September 17, 2011 (UTC)

Also, Amy touches her younger self in this episode too. 110.175.4.178 12:10, September 17, 2011 (UTC)
 * What you have to recognise not all interference in a personal timeline is the same, you have to look at it in context. First I'm going to pull up a classic series example: In Mawdryn Undead two Brigadier's met each other and gave off the same energy that the sonic screwdriver gave off when it touched itself in The Big Bang. This is due to the Blinovitch Limitation Effect and in both cases despite two selves from the same timeline meeting the timeline looped around, eg. the meeting didn't cancel out the future because that future version used to be the past version that meet itself. On numerous cases the Doctor has came into contact with himself, why it hasn't effected him has never been explained but I would guess it has something to do with the fact he's a time lord. And on Father's Day, Rose changed the timeline and caused a grandfather paradox as opposed to an ontological paradox as mentioned with the Brigadier, the Doctor and the sonic screwdiver. The vastly different nature of the paradox allowed the Reapers in; despite to the fact that history was being re-written around them the baby Rose was still the same Rose as adult Rose which caused the Blinovitch Limitation Effect however due to the Reaper's presence the energy was syphoned off to allow another one to get through. And as for kid Amy and adult Amy touching in The Big Bang, they were two different Amy's from two different time lines one from where the universe existed and one from a collapsing universe. Like I said at the beginning you have to take into account the circumstances when it happens. The Light6 13:04, September 17, 2011 (UTC)