## Understanding Quantum Computing

Today, working machines exist to perform a small portion of the more significant tasks Quantum Computers might eventually do for us in the (not so far) future. These working prototypes of quantum computers may serve as the steppingstones for building the real thing.

Quantum computers will be a completely different mechanism than anything we humans have ever made and built throughout history. But what is Quantum Computing? Are there any real-world applications where Quantum Computers will be used? Let us explore a few details and understand **quantum computing** and how quantum computers can shape our future for the better.

Just like classical computers, quantum computers are meant to *solve real-world problems*. However, they manipulate data differently, making them a far more efficient machine than any computer in existence today. What sets quantum computers apart could be explained in a couple of *quantum mechanics principles* on which they operate, **superposition** and **entanglement**.

If it is correct, it signifies the end of physics as a science.

## Superposition

Superposition refers to any quantum object’s counterintuitive ability to exist in more than one “**state**” simultaneously. Take an electron, for instance, the different states it can simultaneously live in could be the lowest energy level and the first excited level in an atom. When ready for **superposition** of the two electrical states, an electron has a little probability of enjoying either of the *two conditions simultaneously*, and it cannot clearly be measured if it’s in the upper -, or lower state.

## Qubits, Superposition, and Quantum Speed-up

**Qubits** are the fundamental information component used in quantum computing. Classical computing uses *transistors as bits*, and they can be either **on** or **off**, as they correspond to the states of 0 and 1. In qubits like electrons, 0 and 1 refer to the two energy levels as described above. Qubits are not the same as the classical bits that must either be 0 or 1 because Qubits can **superpose with changing probabilities**, and that is what *quantum operations* take advantage of during computations.

Qubits are *quantum particles*, unlike electrical circuits, which are charged magnetically in a frigid environment – near-absolute **0K** or **-273.15 °C** temperature. It’s the temperature that keeps these particles in the superposition state and allows them to serve as both **0 (Zero)** and **1 (One)** in binary code simultaneously.

The ‘paradox’ is only a conflict between reality and your feeling of what reality `ought to be

Now, that’s where the *magic of quantum computing* happens. All the particles can assume indefinite states, resulting in something called the “**quantum speed-up**”.

Due to this quantum speed-up, every *qubit’s computing power increases exponentially*, and if enough qubits are packed into a computational device, almost any existing computing technology of today can be outrun.

Though an average user may not need more computing speed than they already have, researchers relying on processor power and computing time in processing Big Data and would appreciate something like the “Quantum Speed-up.”

## Entanglement

Entanglement refers to the phenomenon of creating and manipulating quantum entities in such a manner that they can only be described relating to other quantum entities. There are no individual entities in existence. It is tough to conceptualize entanglement when considering how it can persist over large distances. Once a member of some entangled pair is measured, it will instantly determine its partner’s measurements, which results in extreme speeds.

Quantum computers rely on this very concept between qubits and the probabilities linked with the superpositions for performing a series of operations, enhancing specific chances (the possibilities of the correct answers), and depressing the others, even to zero (the probabilities of the wrong answers).

Once the computation is complete, and the final measurement is performed, there is a maximum probability of getting the right answer. How quantum computers use entanglement and probabilities is something that sets them apart from classical computers.

The history of the universe is, in effect, a huge and ongoing quantum computation. The universe is a quantum computer.

## Why Quantum Computing?

The research in quantum computing aims at discovering a way of speeding up the process of executing long chains of computational instructions. This means of execution would exploit a commonly observed quantum mechanics phenomenon that does not seem to make much sense when written down.

Once this primary goal of quantum computing is achieved, and everything that the physicists are theoretically sure works in the real world, would undoubtedly revolutionize computing.

The mathematical problems that need days of calculations working on today’s supercomputers, and some that even cannot be solved now, would likely get an immediate solution.*Models of climate change, models of the immune system’s capability to destroy cancer cells, estimates on the possibilities of Earth-like planets in our observable galaxy,* and all other *most challenging problems* that we are faced with today might suddenly get results within an hour or so after program execution.

Yes, these results might not be the complete solution, but instead, they could give a probability table that points to the potential solutions. However, remember that even these probabilities are unattainable, using the best-performing supercomputers we have available to us.

## Possible Applications of Quantum Computers

So, are there any real-world applications of quantum computers? What purpose can quantum computers serve, and whom will they benefit? Well, here are some possible applications of quantum computers.

### Navigation

Today’s GPS systems can’t work everywhere, especially underwater. Quantum computers need atoms to be super-cooled and suspended in a particularly sensitive state. Based on this, scientists are working to develop a quantum accelerometer that could give very accurate movement and positioning data.

In this regard, a great initiative was taken by “*France’s Laboratoire de Photonique Numérique et Nanosciences*”, where they tried to build a unique **hybrid component** that pairs a classical and a **quantum accelerometer** and then applies a *high-pass filter* for eliminating the classical data, leaving behind the quantum data only.

As a result, a highly accurate quantum compass is achieved, which eliminates the *scale factor drifts* and bias commonly linked to *gyroscopic components*. Quantum Accelerometers use highly sensitive atom interferometry to measure acceleration along a horizontal axis with applications in navigation without the use of orbital satellites.

### Pharmaceuticals

There has been much research around tackling diseases like *Alzheimer’s* and several *Sclerosis* where scientists have been able to take advantage of software that models *artificial antibodies* and their behavior at a molecular level.

A neuroscience firm named “**Biogen**” started partnering last year with a quantum computing research firm that goes by the name “**1QBit**” and an IT consultancy to come up with a new model of molecular simulation that could run on classical platforms and also on quantum platforms of today and the future.

### Seismology

The same extreme sensitivity of atoms used for navigation could be exploited to detect gas and oil deposits and any related seismic activity. Quantum computers could effectively detect activity in areas where the conventional sensors haven’t explored anything to date. *Quantum gravimeters* can detect the existence of objects hidden deep under the surface by measuring any disturbance in the *gravitational field*. Making this type of device practical and portable would be invaluable to the early detection and prediction of tsunamis and other seismic events.

### Machine Learning

There have been many machine learning algorithms written and thoroughly tested both on paper and in simulators. Some of those algorithms will be used practically on quantum computers once their capacity can handle thousands of Qubits - ever in the future.

The proponents of quantum systems believe that these systems may be capable of learning patterns of different states in massive, concurrent waves instead of successive and sequential scans.

Conventional mathematics can circumscribe various possible quantum outcomes, in the form of vectors in a wild configurational space. Still, it cannot simulate how these outcomes will be achieved.

### Encryption and Decryption

The reason why encryption codes are too hard to break even for the modern-day classical computers is that they are based on factoring huge **prime numbers** and require way too much time to be isolated through “brute force”.

A quantum computer would be able to isolate and spot such factors within a few moments. As a result, the RSA encoding system would effectively become obsolete. In 1994, the first quantum algorithm was devised for factoring different values, and it has already been successfully tested by the experimenters who build low-qubit quantum machines. However, it’s been tested in relatively small quantities.

Once the large-qubit quantum systems are built successfully, they might be able to knock down the entire public key cryptography in use today.

When it comes to encryption, some believe the **Quantum Key Distribution** holds the theoretical hope, at least, that the *quantum keys* will replace the types of public, - and private keys used for encrypting communications today. Theoretically, the encrypted message will be destroyed immediately in case a third party attempts to break encryption.

One must remember, however, that the **QKD** theory is still based on assumptions, which have not yet been tested in a real-world setting. According to this assumption, the values produced with entangled qubits are also entangled and show the quantum effects everywhere they go.

## Conclusion

Quantum computers have the potential to *revolutionize the world of computation* by solving some types of classically intractable problems. While there isn’t any quantum computer built sophisticated enough to date that could perform calculations that can’t be performed on a classical computer (except for the time to solution constraint), significant progress has been made in this field. Some small start-ups and large companies today have functional non-error-corrected quantum computers that work with a few tens of qubits. The general public can even access some of these computers through the cloud. Furthermore, *quantum simulators* have also made strides in various fields ranging from many-body physics to molecular energetic.

In the future, when sophisticated quantum computers are built, the applications of quantum computing could extend to a large number of disciplines and will undoubtedly revolutionize them.