Quantum computing is one of the first great technologies of the 21st century, but the details are still shrouded in mystery. I can explain conventional digital computing down to the electron in a MOSFET, and with this newsletter, I have made it my mission to do the same for quantum computing.

Welcome to the Quantum Edge newsletter. Here you will learn more than just: “quantum computing works because of superposition and entanglement.” The Quantum Edge newsletter will tell you what goes with superposition and entanglement and what those terms actually mean. Here you will read about the physics, chemistry, and all sciences that create the foundation for quantum computing. Join me in my quest to translate the mysteries of the quantum world to the language of the dinner table and the coffee shop.

In today’s newsletter: It’s time to start the discussion on quantum entanglement, the second quantum nonsensical.

According to Wikipedia, quantum entanglement is as follows:

“Quantum entanglement is the phenomenon wherein the quantum state of each particle in a group cannot be described independently of the state of the others, even when the particles are separated by a large distance.”

Entanglement, along with superposition is one of the two key quantum properties that make quantum computers work. Entanglement is used to construct quantum gates and enable quantum data movement. When two or more particles are entangled, action on one can be observed in the other(s).

A qubit in superposition is described, using a vector math formula (called “the wave function”), as a wave of probability that effectively contains more than one value. When the qubit is measured, the wave function collapses and one value that can be read as 0 or 1 is read from the qubit. Within the qubit, the 0 or 1 is carried by the spin state, which is either spin up or spin down. If the qubit is made of a photon, the value comes from the polarization state: vertical or horizontal.

Figure 1 has qubit A in superposition (Asp) and qubit B in superposition (Bsp). If qubits Asp and Bsp are entangled, and Asp is examined, the wave function of Asp will collapse. This will give us a fixed value in A, not in superposition. Bsp will collapse out of superposition at the same time. B will have the opposite value as the qubit A that we measured.

Note the direction of the arrows in the blue A and B qubits in figure 1. A is opposite from B. On top, A is spin down, with the center arrow pointing down and the rotation arrow clockwise. B on top is the opposite. If A is spin up, as on the bottom, B will be spin down.

For the purposes of quantum computing (as we know it today), both A and B will be located somewhere on the same quantum processing unit (QPU) chip. Entanglement and superposition are set up by hitting the qubits with microwave energy at a specific frequency and amplitude.

Amplitude is a word used in electronics to mean how powerful something is. Using the ocean as an analogy, small waves that only extend up from the surface a foot or two would have a small amplitude. They don’t have a lot of energy. Large, powerful waves can reach up to several tens of feet high. These have a large amplitude and carry a lot of energy.

Small packets of electromagnetic wave energy come in the form of photons. The microwave photons are absorbed by the qubit which sets the qubit’s behaviors.

Entangled qubits don’t have to be particles in a QPU. Scientists have created and observed entanglement in particles outside of a quantum computing setting at distances measuring in hundreds of miles.

In the world of physics, entanglement is called spooky and strange. But if you look to the real world, entanglement happens all around us. Let’s take a quick example. Call yourself person A. You share a bank account with a spouse, partner, parent, child, business co-owner, or such. Call them person B.

Now say you (A) are off in another city visiting a friend. B goes down to a car dealership and unbeknownst to you, buys a brand-new electric car. Your financial situation is suddenly changed. You didn’t know it was going to change, and you didn’t have any measure of influence on the change, but your situation suddenly changed. It happened to you the instant that B signed their name to the sales contract regardless of the distance between you and them. That is a real-world example of entanglement.

In that example, entanglement and its effects aren’t spooky at all. Annoying, perhaps, but not spooky. Of course, this is more of a full-size world analogy than an exact representation of quantum entanglement, but it should provoke thought on how an action, at a distance, performed on object A can have an immediate effect on object B, despite no knowledge or signaling passed between A and B.

No one knows. It has been proven to work, but the mechanism that allows it to work is still not understood. We can cause it, see it, and use it, but we don’t know how or why it works.

Joint bank accounts are not the only things that can affect other objects at a distance without a physical connection. Gravity and magnetism can effect change in an object at a distance. Both gravity and magnetism travel at the speed of light though and both involve kinetic or potential energy.

In the banking example, the effect on you is instant, though from a practical standpoint, it only affects you after the financial transaction has been recorded, entered into the computer, transferred here and there and cleared. A direct withdrawal of cash from the joint bank account would be faster in a real sense but also involves propagation delays due to computing and storing activity.

True quantum entanglement seems to be instant and not involve an exchange of energy or information.

More on this subject coming soon.

New to the Quantum Edge newsletter?

Thinking about re-reading it but want a more transportable format?

I’ve wrapped the first ten issues of The Quantum Edge newsletter into book form. The collection, called “The Quantum Computing Anthology, Volume 1”, is now available in Kindle and paperback on Amazon. The book collects newsletter issues 1 through 10 and has some additional material and edits for continuity and clarity.

Coming soon: Volume 2, collecting newsletter issues 11 though 20 is in the works. Look for it on Amazon soon.

In the meantime, you can order the Volume 1 Kindle or paperback editions on Amazon today: The Quantum Computing Anthology, Volume 1

Check your email box Thursday - probably. (Okay, some of these weekly issues have come out on Friday, or not at all. But, in a quantum world, how can you tell?)

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Positive Edge is the consulting arm of Duane Benson, Tech journalist, Futurist, Entrepreneur. Positive Edge is your conduit to decades of leading-edge technology development, management and communications expertise.