the are few and extremal cases ..to the case of traveling in time but more of the cases all those are hteorical ..not possible in reality but the case of the twins paradox is not one of them
Well let time be as it is! no existense is formed with utter perfection, it is not our mistakes in the past that we need to change to be better in the present or have a resentless future, the utter past is nothing but a childs birth; the source of our begining in tis life and the utter future lies in the absence of life. changing any does not change anything in between...ther are still the same features, the same calamities, they occour irrespective of our deeds, one might change the past to make a better future, whereas onother will go bak and undo that so his future can be better.the cycle will go on, limitless and ceaseless. if theres a change possible its in us,if hitles would have not done what he did the jews would have done that to the others coz they were emergining as the most powerful society, time can not be mended, but souls can be changed and thats all there is to make us content(which ofcourse is a broad term, but it also singnifies satisfaction caused due to lesser needs and relieves agony); there wil still be contradictions and it this that makes an equilibrium... people will contradict me and say we can never be content and the chain will triger agian...so lets just let things be, and lets just write history!! who wants to be embeded in the pages of history; well i do!! and i want my name echo across the coridors of time...too much to ask fr, is it?
"the past to change the worst" -- It's judged as worst at this moment (say current time) based on the happening of the "worst" in the past. If you can really change the worst in the past, you don't know whether it will be even worst when you see it in the current time again. A change of history should imply a change of current too. It is a new unknown then.
i would do either, everything happens for a reason it was meant to happen. No matter how bad. We can learn from the past and from those lessons learnt prepare for the future. The past helps us grow the future encourages growth.