I've recently heard of Planck Time.. I read that it is the minimum time interval that can EXIST. What exactly changes in time intervals that are less than Planck time? And if im not mistaken by the meaning of Planck Time; What is the reason that there is such a limit? For Example, the universal speed limit of light exists because you ll simply require infinite energy to accelerate an object enough to reach the speed of light, which is impossible. SO , in the case of Time, what infinite quantity is required to measure below Planck Time. ( I do realize that Im most likely mistaken about my understanding of Planck Time). And while you re at it , I ve also heard of Temperature limit, that objects cannot get hotter than that limit .. Or that physical laws change after that limit, again , why does such a limit exist in the first place? Please , enlighten me. Thanks in advance .