Entanglement – Quantums “spooky action at a distance” ? Well .. no.

The topic of quantum entanglement is an important thing to understand in quantum physics and important to know for quantum computing. In classical computing we work with definite values that are observed the same for however long they exist. In a quantum system the values are not in a defined state.

But what does that really mean ?

Albert Einstein used his colourful commentary when he called quantum entanglement “spooky action at a distance”. When I first started looking at quantum my brain almost broke because I was under the impression that 2 entangled particles were actually connected to each other in some way that when one changes the other changes instantaneously. Surely, this is how we will communicate over massive distances as this evolves. It’s like magic! It is spooky or uncanny but thats not quite how it works.

I know …. hold … keep going … your almost there !

So, whats happening?

When two particles are in an entangled state, there is no action that occurs, that is when one changes state it does not exert a change on the other, which would for example allow a message to be sent instantaneously.

What happens is that after changes occur in state to the 2 entangled particles, say one on earth and one on a satellite in orbit, if you then bring the data from both together, after the fact, there is an uncannily perfect correlation between them. They don’t have the same “value”, but their “values” is correlated. The act of observation causing a quantum wave collapse …. another topic I will cover later.

In my previous post we talked about superposition, well entanglement is a special form of that. It is in this ability of quantum systems to have these multiple states, that with certain types of problems we will ( it is thought ) have extra ability to solve them either at all or quicker, over using classical computing.

This 8 minute video from the Scientific American gives a good overview of the inner workings of a quantum computer.

Quantum Computing is good for certain types of problems, for example when your trying to find a needle in a haystack, this is where quantum computers shine…

Scientific American

If you have some more time you can listen to Neil DeGrasse Tyson and friends on the topic of quantum entanglement. It starts with an analogy to the wishing bone experiment, and is a nicely relaxed explanation and fun discussion. Just about 10 minutes in, Mr. DeGrasse Tyson has a classic penny drop moment, or does a great impression of someone having one… it’s probably the latter. Enjoy!

My Quantum challenge ?

It’s time to become a quantum developer. And yes I will update my linkedin profile to say that! 😉 I will endeavour to learn everything I can in the area of quantum development using IBM’s resources and its software libraries. Where possible I will share all the links out and you can follow along. My “beginners mind” is set and ready to go ( Shoshin) .

Shoshin : It’s the open-minded attitude of being ready to learn; without preconceived notions, judgement or bias.

To follow along then keep an eye out on my blog or follow me on linkedin https://www.linkedin.com/in/andrewpenrose/ where I will share the blog post links and updates.