Sara G. Miller wrote this article for the Scientific American in 2016, right after the second presidential debate between Donald Trump and Hillary Clinton. During that debate Trump stood very close up behind Clinton while she was speaking, Sara writes about the psychology of what happens.
It turns out we lack control over our emotions when someone gets too close, its an automatic, instinctual brain response and it comes from a more primal basic survival mechanism that we share with all sorts of animals from insects to monkeys.
Sara explains a model of personal space bubbles (first identified by American Anthropologist Edward Hall) that describes the space around a person. The first bubble is considered ‘intimate space’ its about 46cms from the body – and its normally reserved for the people we are closest to (family and friends). The second space that is about 1m is ‘personal space’ for friends and acquaintances. The third bubble is ‘social space’ which extends from 1.2 to 3.7m and is for new acquaintances and meeting strangers. The last bubble is the space beyond/
Read the full article its fascinating, on Scientific American (it was published on 13th October 2016)