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What is Quantum Computing? How does a quantum computer work?

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The drive to solve problems faster and more efficiently is never going to stop, and this has led to the enhancements in existing technologies as well as invention several new ones. This hunger, combined with the competitive spirit of scientific research, has led humankind to a new era, the era of Quantum computing.

Quantum computers and quantum computing are technical and complicated as they sound. Quantum computers have been in development for an extended period but have never found practical usage. Scientists believe these technological marvels to be significantly faster than your conventional desktop or even the existing supercomputers. But how do quantum computers work? Read ahead to know all about quantum computing.

How do Quantum Computers work?

Quantum Computers work by performing calculations on the probability of an object’s state before it is even measured. Classic computers work on performing operations on 0 or 1 — the binary states. These 0 or 1 are the definite positions of the physical states. quantum computers can calculate much more data than classic computers using this probability of the state of an object.

Just like modern computing required bits to process data, Quantum computing requires qubits to process and analyse data. Qubit is the quantum state of the object, which is the undefined property of the object before it is detected. These properties include the spin of electrons or the states of a coin when tossed or the polarisation of the photon.

These quantum states of the object can look random but are inter-related or entangled. The superpositions are mathematically relatable to the result, and by putting the quantum states into unique algorithms, we can make advancements in the fields never touched before.

Quantum computers can help solve complex mathematical equations, improve machine learning techniques, producing better security codes and even tackle more complex scenarios.

D-Wave 128-qubit Quantum chipset | Photo by D-Wave Systems via Wikipedia Commons

Because of the potential of processing data at a very high speed and ability to solve complex equations, there are different tech giants such as D-Wave Systems, IBM and Google, that are claiming to be very close to achieving quantum supremacy.

Quantum supremacy is showcasing that a programmable quantum device can solve a problem that classical computers practically cannot within a viable time.

Also read: What is Vsync and should you turn it on or not?

The Race for Quantum Computing

D-Wave Systems is one of the leading Quantum computer manufacturers, and have been producing, selling and setting up quantum computers at various organisation worldwide such as the University of Southern California, Google, NASA and Los Alamos National Lab. D-Wave has already produced a 2048 qubit quantum computer and has announced a much bigger quantum computer.

The company has announced its fifth generation, a 5000-qubit quantum computer that will release in mid-2020. D-Wave has named it Advantage, which uses the company’s latest Pegasus topology that provides better and higher connectivity. This helps in solving more complex problems than before.

In the same year, on October 23, 2019, Google announced that they had achieved Quantum Supremacy. The company said that they have successfully solved a problem that would take a considerable amount of time, even on the most powerful supercomputer available today. Using a quantum computer named Sycamore, researchers at Google performed random circuit sampling. Random circuit sampling is a sequence of random operation done on qubits.

After performing all operations multiple times, they measured the values of the qubits. The researchers received a number distribution close to random but were still interrelated because of quantum effects. Performing all these operations on the most powerful computing platform available will take around 10,000 years, while Sycamore took 200 seconds to complete the operation and all calculations according to the team.

“With the first quantum computation that cannot reasonably be emulated on a classical computer, we have opened up a new realm of computing to be explored”, wrote Google researchers John Martinis and Sergio Boixo in a Google AI blog.

But does this stop here?

IBM Q Dilution Refrigerator | Photo by Graham Carlow for IBM Research via Flickr

Even before Google announced quantum supremacy, IBM published a report on October 21, 2019, in which the tech giant claimed that the calculations by 53 and 54 qubits Symacore circuits can be done using the classic algorithms and within a couple of days.

IBM has also been working on its quantum computer, which has now been available on the cloud by IBM. The company has named it IBM Q System One, and organisations can pay and reserve their time on the machine.

Major businesses and companies such as Goldman Sachs, Samsung, JPMorgan Chase & Co. among other big-wigs, are investing their time and wealth in System One to see how quantum computing can be used in real-life scenarios. IBM has been developing and increasing the number of qubits in IBM Q since May 2016, when it was first launched.

There has been a lot of development in this field, but we still haven’t reached the stage where we can put this technology into daily-life use. There are a lot of areas in which your laptop is much powerful and efficient than quantum computers.

What’s ahead?

Even with the continuous developments and advancements, practical quantum computers are a thing of the future. It will take at least a decade — if not more — for them to replace the computers we are using. To fit enough number of qubits that can solve any problem thrown at it will take years in development.

But if we develop a practical quantum computer, it can track down any information available, decode all the security measures of any platform, mine cryptocurrency with no hassle, and search for a piece of information in a million database within seconds. The possibilities are endless and might even be beyond our imaginations, but the technology needs to evolve, and only time will tell what it has to offer.

Also read: TPU vs GPU vs CPU

Akshit Kansal

Akshit Kansal

A BTech student whose interest lies in automobiles, tech, music, coding and badminton.