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A Full Overview of Quantum Computing

Quantum computing gets a really bad rap for being very complicated, hard to understand, and challenging. For this exact reason many people don’t learn about quantum computing, which is a shame, because it is so awesome!😜

I like this quote from Neil Bohr a lot, which perfectly describes Quantum physics:

“If something is weird, it is an opportunity to expand your understanding”.

This is going to be a long article about everything quantum, so hold onto your hats and let’s dive in!

What is Quantum computing?

Well, in simplest terms, a Quantum computer uses the laws of Quantum physics to complete algorithms and solve problems.

What is Quantum physics?

Glad you asked! Quantum physics is the study of the tiniest parts that make up the universe…like protons, neutrons, electrons and photons. At this subatomic level, all laws of physics are broken and subatomic particles start having their own private party without following any of the rules that apply to other particles. We call these crazy parties that go on in the quantum world: ‘The Phenomena of Quantum physics.’

Some examples of these crazy phenomena are Quantum tunneling, superposition and entanglement.

Background Info

First lets go into some background information;

Classical computers (which is the phone in your hand or laptop on your desk) operate because of the micro-wires and circuits that carry all the information throughout the computer. If you have one wire in a computer with electricity and information flowing through it, the signal can either be on or off. Or any other binary state like true or false, yes or no, spin up or spin down or even 1 or 0. Now, this on/off state in a single wire is called a bit, which makes up the hardware in a classical computer, and is the smallest piece of information a computer can store.

Binary Code (bits)

Bits are in a state of being 1 or 0 at all times. These bits, these ones and zeros, are what make up every classical computer. Bits follow the Binary Number System, (you can read about HERE,) which is basically how any piece of information is represented by bits. For example, every letter/photo/sound correspondes to a series of ones and zeros. This is the basis for how classical computers function.

So, now that you have a little bit of knowledge about how your computer works, we can talk about quantum computers.

In a quantum computer…

Quantum computers also have bits, which we call quantum bits, or qubits. Just like classical computers, qubits can be in a state of either 0 or 1. But, the most exciting and mind blowing thing is that qubits can be in the superposition.

The state of a qubit representing multiple combinations of 0 and 1 at the same time is called superposition. In other words: qubits can simultaneously be 0 and 1 at the same time.

While classical bits are made of tiny transistors, a qubit can be anything that exhibits Quantum behavior, like an electron, an atom, or even a molecule (which all follow the laws of Quantum physics, verses the transistors in a classical computer which follow classical physics.)

This idea of superposition is very hard to wrap our heads around, so let me give an analogy: I can stand up and turn around in a circle to the right. Then I can turn around in a circle to the left. But it is impossible for me to turn around in both directions at the same time. This is exactly what qubits do, all the time.

You may be wondering how you measure or observe something that is in two states at once, how do you know if a qubit is a 1 or a 0? To explain this, let me use the famous Schrödinger’s Cat Thought Experiment, and then I will give you a little more insight into the science.

Schrödinger’s Cat Thought Experiment

I’m sure you’ve all heard some variation of this famous thought experiment: you put a cat in a box with some poisonous gas that has a fifty percent chance of releasing, thus killing the cat, and a fifty percent chance of doing nothing at all. Until we open the lid of the box, we don’t know if the cat will be dead or alive (but not both). If we repeat this experiment enough times, we will discover that half of the time the cat survives, and the other half of the time the cat dies.

The quantum mechanical interpretation of this is that before we look in the box, the cat is in a superposition of dead and alive, and the act of us looking forces nature to pick a state; either dead or alive.

So we can say with 100% certainty, “curiosity kills the cat”.

All jokes aside, the experiment has taught us so much about quantum superposition and what it is.

Now we know that quantum particles (anything found in nature, including particles in the human body!) can be in two states at once. We can leverage this phenomenum to our advantage when creating quantum algorithms and building quantum computers. Think about it: if you have a particle in the superposition, the number of possible outcomes or solutions skyrockets exponentially.

So if you have one qubit, there are 2 possible outcomes, if you have 4 qubits, there are 16 possible outcomes, and with 300 qubits, there are more possible outcomes then there are atoms in the universe, which is so freaking cool!

And now to answer the question that brought us to the Schrodinger’s Cat Thought Experiment: “How do you measure or observe something that is in two states at once?”

Well, as you saw in the experiment, the second we open the box to see what state the cat is in, nature collapses and we are left with either a dead cat or an alive cat. This is the same thing when we measure qubits. The second we observe or measure a qubit, we are forcing the qubit’s wave function to collapse, which leaves us with a binary state, 1 or 0, which we can easily measure.

Look at this awesome gif explaining superposition: when no-one is looking, the qubits are in a superposition of being 0 and 1 (or in the middle of 0 an 1), but the moment someone goes to measure or observe the qubit, it chooses either 0 or 1. So it is physically impossible as humans to observe/measure a qubit in the superposition.

Let me solidify why the superposition is so important: Our world, and nature, is quantum itself. This is why real-world quantum systems can’t be modeled on a classical computer. One example is if we give even our most powerful supercomputers the task to model Calcium Monofluoride (CaF), the supercomputer would be off by 70–200%! This makes even the world’s most powerful supercomputers useless. Our classical computers are so off when modeling these natural compounds because in nature, electrons are orbiting around the nucleus in a superposition state, something that’s impossible to depict on a classical computer. Quantum computers can easily solve this problem, since they themselves operate in superpositions. Do you now see how crazy powerful Quantum computers are?!?!?!

Quantum Tunneling

Another phenomenon in the quantum world in quantum tunneling.

Again, time for some background:

One of the big ideas in quantum physics is that light can behave as a particle AND as a wave.

First let’s define what a wave is in the quantum world.

A wave can be described as a disturbance that travels through a medium from one location to another location. To understand this, think of a wave as a slinky. When you stretch out a slinky, each coil spaces out creating it’s natural equilibrium state. Now imagine you shake one end of the slinky a fraction. Naturally the slinky will bob up and down because it was disturbed out of its equilibrium state, but in a matter of seconds it will return back to equilibrium. In physics we call this a pulse: a single disturbance through a medium from one location to another. Now imagine you repeatedly shake the slinky up and down. We would see a repeated disturbance moving throughout the slinky. This repeated disturbance is exactly what a wave, or a wave function, is.

Now let’s talk about particles.

Particles, unlike waves, cannot change states. You can’t jiggle a particle up and down and expect to create a disturbance. Particles are solid(ish) objects that keep their form and are constantly moving in tiny vibrations.

As you can see, waves and particles are so incredibly different. So how can light/electrons/protons be both? And how do we know if we’re observing a wave or a particle?

The answer to that question is: it depends. (No joke! Every Quantum physicist answers this question by saying “it depends”!)

It depends on the problem, when you observe a quantum particle, how you observe a quantum particle, and what their function is in your experiment.

I’m not going to get into the science behind how particles can behave as a particle and a wave, but the important thing to know is that quantum particles ARE both waves and particles (just like how quantum particles are 1 and 0 at the same time) they are also a wave and a particle at the same time.

Now using our new knowledge about wave functions and particles, lets see how this relates to Quantum Tunneling.

This moment calls for a thought experiment.

Let’s pretend that we have an electron that is trying to get over a potential barrier. In classical physics, we would have to give the electron enough kinetic energy to get over the barrier, and if there wasn’t enough energy, then the electron would roll back to where it was. (But of course since quantum mechanics is quantum mechanics, everything changes in the quantum world.)

Lets take that same electron with the same amount of kinetic energy as in the previous example, and let’s push the electron toward the potential barrier.

In quantum mechanics there is a chance that the electron particle will “turn into a wave” (I use those words in the loosest sense) and tunnel straight through the barrier, like in the picture below.

A Simple Drawing Of Quantum Tunneling

When objects in the quantum world tunnel through barriers, it is not interfering, harming or even touching the barrier. The quantum object just tunnels straight through. (Like Harry Potter tunneling through through the wall to catch the train to Hogwarts at platform 9 3/4.)

Why then is quantum tunneling useful or important?

  • Quantum tunneling is what gives quantum computers the potential to not only complete tasks exponentially faster, but to also complete tasks that classical computers couldn’t typically handle. (To reiterate, quantum tunneling happens at the speed of light, which is the main reason why quantum computers are so fast.)
  • Quantum tunneling is a necessary part of nuclear fusion
  • Quantum tunneling is what led to the invention of Quantum-tunneling Composite (QTC) which is found in mobile devices and is typically used as a switch.
  • By pairing Quantum tunneling and Quantum superposition we can take over the world!!!! Mwoa-ha-ha!! (I’m joking. Sort of.) With both quantum tunneling and superposition, we can create highly efficient and very quick quantum algorithms. By using these quantum algorithms, almost anything is possible on a quantum computer.

Okay, so that is a quick overview of quantum tunneling. Moving on to the next part, let’s take a look at quantum entanglement.

Quantum entanglement

FUN FACT <<<You will sometimes hear Quantum entanglement referred to as ‘Einstein’s Mistake’ since Einstein did not like the idea of entanglement and since researchers have proven that quantum entanglement breaks Einstein’s Theory Of Relativity. (Don’t tell Einstein!😂)>>>

The last big phenomenon in the quantum world is quantum entanglement.

Entangled Photons Of Light

Let’s say that we have two photons of light that are doing their thing, but then collide into each other. These two photons, photon A and photon B, are now entangled. Even though photon A and photon B are very far apart (since photons travel at a speed 670,616,629 miles/hour), when you go to measure photon A (let’s say that we measured the spin state, and it was spin up, which is the same as being 1), photon B, since the two photons are entangled, will take up a state relative to Photon A (for this example, spin down, which is the same thing as 0).

Pretty cool, right?!

This phenomenon could open up a whole new world of possibilities which we are now just beginning to discover. Some examples include:

  • Could be used to cut down the amount of time it takes to send information to qubits within a quantum computer.
  • Could be used for instant communication. (We could have billions of entangled particles all around the globe. Sending a message by harnessing these entangled particles could revolutionize communication!)
  • Quantum entanglement is a vital role in how quantum computers work.

The Parts Of A Quantum Computer

Here is a picture of a Quantum Computer with the shells taken off. Looks like something out of a sci-fi movie, right?! But it’s not out of a sci-fi movie, we already have dozens of Quantum computer hooked up to the cloud, with over 30 000 active users running over 1 billion experiments/simulations a day!

The five main parts of a quantum computer are:

An IBM Quantum Computer
  1. Shell. There are 5 shells covering a quantum computer, (like the one shell shown at the top of this picture), protecting it from light, noise, dust/dirt, and keeping the temperature very cold. Each of the 5 shells nestle together, acting like big blankets.
  2. Nerves. These are the cables (sometime referred to as “microwave lines”, since the wires in a quantum computer and a microwave are made up of the same substance), and they connect everything in a quantum computer, which carry signals to and from the qubits to carry out the function before returning the result.
  3. Skeleton. These are the circular gold plates separate cooling zones, (there are 3 plates, and the temperature gets colder the farther down you go). The bottom plate plunges to one-hundredth of a kelvin, which is hundreds of times as cold as outer space! (Kelvin is the unit of temperature that we measure the coldest things in the world with).
Closeup of the nerves (the wires),

4. Heart/mixing chamber. The very core of a Quantum computer is the mixing chamber. This is where liquid helium (helium 3 and helium 4) separate and evaporate, diffusing the heat, thus cooling down the temperature of the whole system. The metal rod basically just helps with the reduction of force applied to a qubit.

5. Brain. The brain (or QPU — Quantum Processing Unit-) is where all the magic happens! The QPU is a circular gold plate located at the very bottom of the computer which holds the silicon chip, which is the computer’s brain. The QPU runs all of the computational components to reach the solution for a problem. (Refer to the closeup of an IBM Quantum chip below.)

IBM Quantum Chip

The shell, nerves, skeleton, heart/mixing chamber and brain are the main parts of a quantum computer. Of course there are many other very important elements, like the Qubit Signal Amplifier, which despite it’s fancy name, is only a refrigeration device for the qubits as they initially enter the computer, and the Cryoperm shield which protects the qubits as they travel throughout the computer from electromagnetic radiation, in order to preserve the quality of each qubit, just to name a few other parts.

The Three Different Kinds Of Quantum Computers

There are three different types of quantum computers: Quantum Annealing, Analog Quantum, and Universal Quantum.

Quantum Annealing

Quantum Annealing is the least powerful and most restrictive of all three quantum computers. It can only handle certain functions and equations, and are generally used for smaller projects. We also don’t have any proof that a Quantum Annealing is faster than a classical computer. On the positive side, Quantum Annealing is the easiest quantum computer to build, and is good for solving optimization (Ex: finding the lowest energy level) and sampling problems (Ex: trying all the possible configurations of something at once).

Analog Quantum

Analog Quantum Computing is more advanced than Quantum Annealing. Analog Quantum Computers are harder to build than Quantum Annealers, but they can solve much greater and more complex problems. Most companies that use Analog Quantum Computers (like Rigetti, IBM and Google) use Analog computers because of their computational powers and reliability. Analog computers have between 50 to 100 qubits, and Google has demonstrated that it’s 54 qubit Analog quantum computer could solve a problem in only minutes, what would take a classical computer 10,000 years! (this is described as Quantum Supremacy, the moment when a quantum computer can solve a problem quicker than a classical computer.)

Universal Quantum

This is the be-all-end-all for quantum computing. The “holy-grail” of quantum computing. Tech giants like Riggeti, IBM and Google are now in somewhat of a race to see who will build the world’s first Universal Quantum computer. The Universal Quantum computer is the largest and most powerful quantum computer, but in turn, it is the hardest and most complicated to build. Current estimates point in the direction of 100,000 qubits in one machine. Timelines for building the world’s first universal quantum computer point around 10–20 years…so we’re still a far way out.

How a Quantum Computer Works

The following steps outline how the main parts of a quantum computer work together to solve a problem.

Sourced from IBM. A simple Qiskit circuit model.
  • Create a Quantum Circuit Model, which is basically a diagram describing a quantum algorithm (a road map) built mainly of quantum logic gates . A very simple diagram of a Quantum circuit model is shown to the left.
  • Connect your computer to a cloud platform (Ex: IBM uses Qiskit, Rigetti uses PennyLane or Strawberry Fields, and Xanadu uses Strawberry Fields with some cross-Python, Google uses Cirq). These cloud platforms are quantum circuits that tech companies designed to make it easier for everyday computer programers to use (programing a circuit model is VERY difficult and tedious). These companies have gotten to the point where all you need to know is a coding language (usually Python), and once connected to the cloud, you can code away!
  • “Let the magic happen”. The next step is just letting the quantum computer do it’s thing (the Circuit Model is already programed to carry out these steps).The quantum gate sends out microwave pulses and instructions through the nerves of the quantum computer to the computer hardware/chip, telling it to execute the quantum gates and return the answer in classical bits.
  • Returning the answer to the cloud is the next step. The superconducting electrons travel down through the nerves and to the brain of the quantum computer, through the cord that the quantum computer is plugged into the electrical outlet with, and then to the cloud, where the answer is returned in classical bits, to your computer.

Quantum Tech Giants

Who is leading the pack in this mad race to the quantum computing finish line? Well, there are many key contestants, and other smaller ones as well. let’s check out these quantum race contestants:

IMB Q ~ IBM Quantum is arguably leading the pack in the quantum race. IBM Q has already paired up with Mercedes-Benz in creating new electric vehicles that can dominate that are carbon neutral by 2030. The largest factor that is holding electric cars back right now is that we don’t know what goes on inside a battery. Sure we know how to make batteries, but we don’t know what goes on in a molecular level inside the battery while it’s working. There is no supercomputer on the planet that can accurately simulate what goes on in the battery. Having this information is the only way that we can improve electric vehicles. You know what this problem calls for (*drum roll, please!*)…Quantum Computers! IBM Q is working on creating more efficient and effective batteries that will soon dominate the planet, and hopefully help save our planet.

IBM Q has over 20 quantum computers all over the world, running one billion executions a day on the IBM cloud. This technology is opened up so that anyone from anywhere on the planet can use this technology. You can start coding a quantum computer right now using IBM’s quantum programming language, Quiskit.

D-Wave ~ D-Wave is probably the most well known quantum company, since it is leading the world in the development and delivery of quantum hardware and quantum systems. D-Wave is also well known for being very easy to start programming on using Leap. While D-Wave isn’t solving real-world problems like IBM Q, D-Wave has over 100 quantum researches, working on creator better, more efficient and reliable quantum computers. D-Wave just announced a 5000 qubit system to be available in mid 2020! That is 50 times larger and more efficient than the quantum computers we are using now!

Rigetti ~ Rigetti takes a slightly different approach to Quantum computing, by designing quantum computers with superconducting qubits. What this means is that Regetti harnesses the power of entanglement to join qubits together, filter them through a race-track-like-grove in the quantum chip, and cool them down to a very low temperature. After this process, you have superconducting qubits which are about 100 times more powerful than regular qubits!

In 2014 Regetti opened a QxBranch which is a data analysis and quantum computing software company. This branch of Regetti was created to expand capabilities of quantum computers, and train elite experts to design better quantum computers.

Xanadu ~ Xanadu is quite different then any of the companies I have mentioned about. Xanadu’s Quantum computers use silicon photonic chips which work much differently than regular quantum chips (watch a video of Xanadu’s quantum chip in action here.

Xanadu is also the first company dedicated to quantum machine learning, which pairs quantum computing with artificial intelligence using PennyLane. Xanadu is known for really educating the public, by putting on webinars, hackathons, and many tutorials.

Google ~ of course Google didn’t want to be left out of the loop, so Google created Cirq. Google holds many records for quantum computing, like how Google’s 54 qubit quantum computer was able to preform a calculation in 200 seconds that would have taken the world’s most powerful supercomputer 10,000 years! Google’s new goal is to build a fully functioning universal quantum computer by 2029 (*excited emoji*). Google Quantum computing doesn’t get as much publicity as IBM Q and Xanadu, but Google has already made 1 big breakthrough in quantum computing, so my bet is that Google is just waiting to pounce.

Obstacles Facing Quantum Computers

Everything in life has obstacles…and this is especially true with quantum computers. We have come so far in 20 short years, but we still have a way to go. Here are the key obstacles that Quantum computers face:

  • Decoherence — A really big problem with Quantum computers is decoherence, which happens when qubits are exposed to “environmental factors” (noise, dust/dirt, wind, or temperature). Qubits are ultra sensitive, and will lose their power and ability to function if exposed to environmental factors, causing errors in the calculation and result. This is why when you see a picture of a quantum computer, it looks like a big white cylinder (the “cylinder” that you see is actually 5 nestled cages protecting the actual quantum computer.), or something like the picture below, which is the massive refrigerator for the quantum computer.
D-Wave Quantum Computer in refrigerator
  • Extremely cold temperature — Another big obstacle with Quantum computing is the extremely cold temperature that Quantum computers require. Heat is the enemy of Quantum computers, because it creates error in the qubits and messes up the calculations. This is why quantum computers are kept in large refrigerators that keep the temperature at absolute zero/one hundredth of a kelvin(which is -273°c).
  • Low malleability — the wire used to make the nerves in a quantum computer are quite rigid and hard, making it very difficult to work with. The whole process of building a quantum computer becomes more expensive, more difficult and more time consuming since the wires are so hard to work with, making mass production and manufacturing incredibly difficult.
  • Quantum computer are “too good” — you may think that being “too good” is not an obstacle, but when it comes to encryption, quantum computers are definitely “too good”. Peter Shor developed Shor’s algorithm in 1994 which can break very large numbers down into primes. That doesn’t sound very exciting at first, but most online security systems like banking and encryption, rely on the principle of taking a very large number and breaking it down into it’s prime factors. These problems (called ‘NP’ problems which break very large numbers down into primes.) would take billions of years to solve on a classical computer, but only a couple hours on a quantum computer. And that isn’t good, because we could accidently break the RSA code by just putting a Quantum computer on the web. “Whoops!”

Our Future with Quantum Computing

Quantum computers are great at solving problems with limited inputs and almost infinite possibilities/answers. An example of this kind of problem would be an encryption code, where one very large number is the input, and there are infinite possibilities that could all be possible outputs. Another example of this kind of problem is trying to track the longest possible distance from two cities. The input is the map data, road distances, etc., and the output is just one number- the longest distance. These kinds of problems are actually impossible for a classical computer to solve, but with a Quantum computer these problems could be solved in a matter of hours.

Now lets take a look at the real-world problems that Quantum computing can solve.

  • Molecule simulation — remember how earlier in this article I mentioned how it is impossible for classical computers to accurately simulate anything found in nature? Well, this is what quantum computers are literally made for! Since Quantum computers operate from qubits themselves (which is what most elements of nature are made of), Quantum computers can precisely model the chemical buildup, traits, properties, etc., of a molecule! We have never been able to do this before, so we could discover new information about the universe that NOBODY KNEW EXISTED!!!
  • Drug discovery — it takes on average 10–50 years for a new medicine to complete the journey from research to customers. That is a heck of a long time! Now let’s throw Quantum computers into the mix, and BOOM!, the whole process is done in a couple hours! Quantum computers provide us with more contextual information, allowing us to see the chemical build of molecules, bonding between molecules and chemical reactions in the body, providing clear insight for us, so all we have to do is manufacture the drug. How freaking cool is that?!
  • Boosting Artificial Intelligence training — a highly discussed topic right now is the possibility of pairing Quantum computing with AI to maximize efficiency and yield the results we would like. AI operates on large datasets, which can be very difficult to come up with, and just as hard to program. There is lots of room for error and inaccuracy. Quantum computers can reverse this by enlarging and enriching datasets, and simplifying them, making it easier to program. We might even get to the point where quantum computers can program a robot for us! (But we’re still a ways away from that.)
  • Instant and very accurate weather tracking — every year there are thousands of hurricanes, tsunamis, extreme heat waves and other extreme weather events, resulting in thousands of lives lost and billions of dollars in damage. Now imagine if there was a technology that could accurately predict extreme weather, sooner in advance, so people and governments could better prepare. That would be right out of a sci-fi movie, right? Wrong. That is Quantum computing! Quantum computing has the potential to improve numerical methods to improve tracking, and handle huge amounts of variables (most things in nature are variables, but especially weather. Ex: there is a 50% chance of rain today, but a 23% chance of it being sunny in the evening.), and since qubits are literally a variable themselves (“I have a 50% chance of being a 1, and a 50% chance of being a 0”), quantum computers could literally revolutionize the way we forecast weather. We can use this same idea on a local scale for weather stations and accurate predictions.
Inside Google’s Quantum Computing Lab 2018
  • Gene analysis — Quantum algorithms can easily classify genomic data, and determine if a test sample comes from a disease (and then classify which disease), and it can depict the different molecules in any given sample. This process is very similar to how Quantum computers can aid in molecule simulation. By pairing quantum computing with machine learning, it is possible to have a completely accurate diagram of DNA, molecules, and particles in the human body and animals, and then we could break those molecules and particles down to see each molecule/particle is made of! A highly discussed topic now is how we can simulate a coffee molecule to see exactly how coffee effects the brain and the human body, which has never been done before.
  • Finance industry — you may be surprised to hear that even the finance industry will benefit from Quantum computing. Specifically in fraud detection, which relies largely on pattern recognition and data processing. As great as classical computers are, they can only handle so much, making it possible for hackers and scammers to break into the system. Quantum computers can help detect fraud early on and significantly increase the speed of analysis thanks to their amazing computing capabilities and speed.
  • Very efficient cyber security based on quantum algorithms — although I did mention that Quantum computers can break the RSA code, if we organize our data differently and code our important information in quantum algorithms, then pair our quantum computers with blockchain, and you have a fool-proof system that is virtually impossible to hack into or break.

Pretty cool, huh?! And the list doesn’t just stop there, Quantum computers can show patterns in the stock market, help with the accuracy of mass manufacturing (for example, a computer chip which takes several hours for a human and has lots of room for error), and even translate an extremely long document in a foreign language in seconds. So the options are incredibly vast!

Here is a quote from Richard Feynman, who was instrumental in the formation of quantum physics, that sums up the future of Quantum computing:

“Accurate modeling has applications for engineering, medicine, energy production and much more. Quantum computers can keep up with the (true) complexity of nature. We could model the world/reality for the first time.”

TL; DR (Too Long Didn’t Read)

  • Classical computers operate using bits, which is the smallest piece of information a computer can hold. These bits can be either 1 or 0.
  • Quantum computers operate using quantum bits, qubits, which can be 1 or 0 as well, but they can also be 1 and 0 at the same time (explained more below).
  • Quantum computers harness the weird laws of quantum physics to solve problems. Some of these ‘weird laws’ include:
  1. Superposition ~ the reason why Quantum computers are so powerful is because a qubit can be in a state of 1 and 0 at the same time. This means that the possible combinations of a problem goes up exponentially.
  2. Quantum Entanglement ~ when two particles touch each other and are now in a state relative to each other
  3. Quantum tunneling ~ when a qubit ‘turns into a wave’ because of the wave/particle duality, and tunnels straight through a barrier without having to travel over the barrier.
  • There are 5 main parts that make up a quantum computer: the shell (the ‘cages’ that protect quantum computers from natural elements), the nerves (the microwave wires that the qubits travel through), the skeleton (the gold plates and physical material that makes up the computer), the heart/mixing chamber (where liquid helium 3 and 4 evaporate, an important process for a quantum computer), and the brain (the quantum chip located at the bottom of the computer which is where the signals are sent out to the qubits and where the ‘magic happens’.)
  • There are 3 different kinds of quantum computers: Quantum Annealer (which isn’t proven to be any quicker/more efficient than a classical computer), an Analog Quantum Computer (which is what most quantum companies use now. They are powerful and can solve problems much quicker than classical computers), and a Universal Quantum Computer (the be-all-end-all of quantum computing is creating a Universal Quantum computer which companies are working on now (about 10–20 years out). A universal quantum computer would be made of 10 times the amount of qubits we are making our quantum computers with now, and that would mean that it would be unbelievably powerful.)
  • The tech giants in quantum computing are IBM Q, Regetti, Xanadu, Google and D-Wave.
  • Some obstacles facing quantum computers are that quantum computers are ultra sensitive (can’t be exposed to light, noise, dirt/sand, etc.), quantum computers need to be kept at temperatures just below 0 kelvin (which is hundreds of times colder than outer space), and the problem that quantum computers could crack the RSA code.
We have no clue what a caffeine molecule looks like, so we don’t know how exactly caffeine effects the brain. A quantum computer could accurately and precisely simulate a caffeine molecule that is much more accurate then the chemical formula above.
  • In the future Quantum computers can accurately simulate molecules which lead to much quicker drug discovery, accurate weather tracking/prediction, aid in AI training, finance, and very efficient security.
  • You can start using a quantum computer NOW with Quiskit, PennyLane, Cirq or Leap.


You now have a pretty good full overview of quantum computing. You have dipped your toe into the quantum computing world, and, if I did my job correctly, you have learnt a lot, and are inspired to learn more.

So CONGRATS on learning more about quantum computing!🎉

Until next time,

peace out!

(p.s. — some resources for further learning about Quantum computing:




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Rachel Lee

I’m a 16 y/o biotech lover, podcaster and ultra runner using biotech to improve agricultural productivity in Africa.