“IT FROM bit.” This phrase, coined by physicist John Wheeler, encapsulates what a lot of physicists have come to believe: that tangible physical reality, the “it”, is ultimately made from information, or bits.

Concepts such as entropy in thermodynamics, a measure of disorder whose irresistible rise seems to characterise our universe, have long been known to be connected with information. More recently, some efforts to unify general relativity, the theory that describes space and time, with quantum mechanics, the theory that describes particles and matter, have homed in on information as a common language.

Inside knowledge: The biggest questions about facts, truth, lies and belief

Forget alternative facts. To get to the bottom of what we know and how we know we…