Decoding quantum reality - with Vlatko Vedral

For a physicist, all the world is information, with the Universe and its workings reflecting the ebb and flow of data. We ourselves are transient patterns of information, passing on the recipe for our basic forms to future generations via a four-letter digital code called DNA. In this talk, quantum physicist Vlatko Vedral delves into some of the deepest questions about the Universe, interpreting it in terms of information. He explains the nature of information, the concept of entropy, and how these ideas are rooted in thermodynamics. Discover the bizarre effects of quantum behaviour, such as 'entanglement'—what Einstein famously referred to as 'spooky action at a distance'. Vlatko also explores the leading-edge work on harnessing quantum effects in hyperfast quantum computers and discusses recent evidence suggesting that the weirdness of the quantum world, once thought to be limited to the tiniest scales, may extend into the macro world.

From his book Decoding Reality:

...An amazing issue to note is this. The above meditation in realizing emptiness is a very similar exercise to von Neumann’s number creation out of empty sets; it just goes in the exact opposite direction. Von Neumann went from an empty set into an infinite set of real numbers and here we started with macroscopic objects and deconstructed them to find that actually there is nothing behind them, they are based on randomness, on no prior information.

This is the darkness of reality! Anything that exists in this Universe, anything to which you can attribute any kind of reality, only exists by virtue of the mutual information it shares with other objects in the Universe. Underneath this, nothing else exists, nothing else has any underlying reality and hence there is no infinite regression. It just has to be this way, as otherwise we are asking a finite Universe to contain an infinite amount of information – and this is clearly not possible!

Following this logic, it’s more accurate to think of the evolution of the Universe as starting with all potential realities from which one reality simply emerges. From this initial state, which contains all possible subsequent futures, the first event occurs without any cause (i.e. a random event) and this gives us our first bit of information. So from all possible futures, now we have a smaller number of futures simply because the first event has occurred in a specific way and all subsequent events will have this event as their past. In this way mutual information is established between bits...

...So how does the act of observation allow one reality to emerge out of two or more realities? Quantum physics seems to imply that reality somehow emerges through interactions between observers and the observed...