Lactate uptake by the liver is diminished with metformin administration because lactate is a substrate for hepatic gluconeogenesis , a process that metformin inhibits. In healthy individuals, this slight excess is cleared by other mechanisms (including uptake by unimpaired kidneys), and no significant elevation in blood levels of lactate occurs.  Given impaired kidney function, clearance of metformin and lactate is reduced, increasing levels of both, and possibly causing lactic acid buildup. Because metformin decreases liver uptake of lactate, any condition that may precipitate lactic acidosis is a contraindication. Common causes include alcoholism (due to depletion of NAD+ stores), heart failure and respiratory disease (due to inadequate tissue oxygenation); the most common cause is kidney disease. 
This is just one explanation, there are countless ways to frame this logically without involving Cern. While I admit that past states of spacetime may very well decay or deteriorate just like the deteriorating material that we use to define them, I have to assume that this is very much an unlikely reality given the considerable number of more logical, scientific evidence driven possibilities. Even if such decay did occur, to credit humans with creating it is, I must say – quite absurd, laughable even. For the record, if you understand the basic idea of the anecdote here, then I’d be happy to provide the actual science behind it. The actual theory in it’s literal form is completely neurologically based, but i figured an anecdote would do a better job of conveying the basic idea than to rattle off a bunch of terms and concepts that most of the public doesn’t understand.
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