# Quantum Computing – The Computing Technology of Tomorrow

Quantum Computing is a subject that can boggle even the most genius minds!!! It deals with topics that are considered science fiction by normal people like **parallel universes, multiverse theory**, etc. In fact, it sounds more like the next Marvel Dr. Strange movie and less like an actual technology!!!

But Quantum Computing is very real. It is a computing technology based on the laws of **Quantum Physics**, which deals with the behavior of energy and matter at the quantum level (That’s the atomic level!). And a fully functional Quantum Computer would be able to perform multiple calculations simultaneously which would increase its speed a million times more than even the most powerful supercomputers today! In fact, Quantum Computing could change entire industries in the future like Healthcare, Finance, Telecommunications, Cybersecurity, etc. with its insane capabilities. And that is why this article focuses on **Quantum Computing and its Potential Applications in the Future.**

But before going into the future, let’s go into the past. **So what was the beginning of Quantum Computing?** It all started with physicist Max Planck in 1900 when he discovered the energy quanta, which are tiny little packets of energy at the subatomic level that can behave as both waves and particles depending on their environment at the time. This discovery became the basis of the Quantum Theory which earned Max Planck a Nobel Prize in Physics (Yup, it was that important!) and also led to the start of Quantum Computing.

An interpretation of the Quantum Theory is that if an object such as an electron or a photon can potentially exist in multiple states then there are a series of parallel universes for that object with each possible state of the object corresponding to a parallel universe. This is known as the **Many-Worlds Interpretation** or multiverse theory which is supported by many scientists including Stephen Hawking.

But we still haven’t addressed the all-important question…**What is Quantum Computing?** So let’s get to that now.

### What is Quantum Computing?

The computer (that includes a phone!) you are using to read this article is a prime example of classical computing. Now modern classical computing methods work on chips that process all the data using just a bit with two possible states **0 and 1.** Even the most complex problems or algorithms you see in classical computing is understood by the computer by breaking it down into 0 and 1. However, there are some problems that are so huge or complex that it is impossible to solve them with even the most powerful classical computers on Earth!!!

That’s where Quantum Computing comes in! Universal Quantum Computers use the unit **qubits** (quantum bits) instead of bits. A qubit could be an electron in which the 2 different states are the **upward spin or downward spin** of an electron or even a photon, in which the 2 different states are the vertical polarization and the horizontal polarization. Now, in Classical Computing, a bit has to be in a single state, either 0 or 1. But in Quantum Computing a qubit can be in both states (0 and 1) simultaneously, a property that is called **Superposition**. Only when the qubit is actually measured, it has to decide whether it is 0 or 1. This can be understood as a flipped coin, that can heads and tails simultaneously. Only when it lands on your hand, then it is clearly heads or tails.

**For example:** If there are 4 bits, then these bits together can represent 2^4=16 values in total but they can only hold 1 of these 16 values at a time. But if there are 4 qubits, then these qubits together can hold of these 16 values simultaneously! That’s the magic of Quantum Computing!!!

Another important property of Quantum Computing is **Entanglement.** Qubits that have interacted at some point are entangled in pairs. So if the state of one qubit in this pair is known, suppose its upward spin state, then the state of the other qubit is automatically and simultaneously in the downward spin state. Entanglement among 2 qubits is valid no matter the distance between them, as long as they are in isolated conditions. This amazing phenomenon does not have an explanation yet and it was even called **“spooky action at a distance”** by Einstein!!!

### What is Quantum Supremacy?

What would be the use of a Quantum Computer if it could not be at least better than Classical Computers? This is where **Quantum Supremacy** comes in. Basically, Quantum Supremacy is the proven ability of a Quantum Computer to solve problems that Classical Computers practically cannot solve. The race to build the most powerful quantum computers that could attain Quantum Supremacy has been going on since the late 1990s. However, Quantum Supremacy is still a hypothetical situation that no company has been able to achieve yet.

In March 2018, Google had claimed that its 72-qubit quantum computer chip Bristlecone might be able to confirm Quantum Supremacy in the future. But Alibaba refuted these claims by using multiple classical servers to simulate the working of Bristlecone and achieve the same result. Since a Classical Computer could solve the same problem, this meant Google’s Bristlecone had not yet achieved Quantum Supremacy.

But that was not the end of this Quantum Computing war! Now again in October 2019, Google claimed in the journal Nature that their latest quantum processor Sycamore had executed a random number generation problem in 200 seconds which would take Summit from IBM approximately **10, 000 years**. But IBM refused this conclusion by saying that Summit could perform this task in **2.5 days** by various performance enhancements that Google had not considered in their research.

So basically, in current times Google is making claims of Quantum Supremacy while various companies are refuting these claims. There is no clear consensus on whether Quantum Supremacy has been achieved and various tech companies like **Google, IBM, D-Wave Systems, Alibaba**, etc. are in the race to be the first!!!

### What are the Potential Applications of Quantum Computing?

Quantum Computing might be the future of the tech world! According to **Vern Brownell, CEO of D-Wave Systems** which is a Canadian Quantum Computing company “We’re at the dawn of this quantum computing age. We believe we’re right on the cusp of providing capabilities you can’t get with classical computing. In almost every discipline you’ll see these types of computers make this kind of impact.”

In fact, there are many possible applications of Quantum Computers across various fields. Let’s see some of these now:

**1. Healthcare: **Want a medicine tailored to your unique DNA structure and genomes? This could potentially be possible using Quantum Computing. Studying the complete DNA of an organism requires a large amount of computational power and storage space which is quite difficult to accomplish using Classical Computing. However, Quantum Computing would make this process much easier allowing us to understand individual DNA at a much deeper level and also cure many genetic diseases.

**2. Finance: **Finance involves market prediction in order to make more money! Now there are many algorithms that use multiple probabilities and assumptions to calculate the future market trends. Quantum Computers can be immensely helpful in this scenario as they can eliminate the blind spots and errors in the data which leads to wrong financial forecasts (And thus a loss of money!)

**3. Cybersecurity: **Do you know that the insane speed of Quantum Computers could be used to crack the cryptographic codes that keep our messages and sensitive data a secret? But at the same time, Quantum Computers could also be used to protect the data from hacking using Quantum Encryption. It involves sending photons over long distances using the Entanglement Principle to secure the data.

**4. Agriculture: **Fertilizers are very important in Agriculture!!! And they are made primarily of Ammonia. But did you know that we still use a technique from the 1900s to create Ammonia which requires extreme pressure and heat? And no new process for creating Ammonia has been discovered as there are millions of possible catalyst combinations to try. Solving this problem on a Classical Computer may take ages but this can easily and speedily be done on a Quantum Computer.

**5. Artificial Intelligence: **Artificial Intelligence is interesting on its own and Quantum Computing could make it almost magically diverse. Complex algorithms could be created on Quantum Computers that may be able to map out trillions of neurons in the human brain and contribute hugely in the field of neural networks. Also, Quantum Computing could be used in combination with ML to create IoT devices that are deeply interconnected with insanely complicated cybersecurity protocols.

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