Historian: Oxford Dictionaries named "post-truth" as the 2016 international word of the year [link]. We take a hard line on "truth" by saying that you can only find "truth" in logic and mathematics and in religion — everything else is far too messy for "truth" to apply.
Physicist: We can take that hard line, but we can not change the way people use "truth" especially scientists. When the American Association for the Advancement of Science [link] Uses "scientific truth," what does this mean? This means science can give us trustworthy evidence [link], sometimes so trustworthy that there is no reasonable doubt. But, in a post-truth world, trustworthy evidence carries no weight.