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What is Quantum Computing?

What is Quantum Computing?

Quantum Computing is a form of computing that takes advantage of quantum mechanics to process information exponentially faster than classical computers.

Classical computers use classical bits which can consist of either a 0 or a 1 to encode information.Quantum computers,on the other hand,qubits, like photons,atoms, ions, etc. to encode information into 2 distinguishable quantum states .

Now you may be thinking, what’s the benefit of using qubits over classical bits? The answer lies in the ability of qubits to behave quantumly, specifically the quantum phenomena of superposition and entanglement.




Lov Grover created this algorithm to solve the problem of an unstructured search. It can find the unique input to a black box function that produces a particular output value, using just O(sqrt N) evaluation of the function, N being the function’s domain.

Shor’s algorithm is by far one of the most famous quantum algorithms of all time, as it can factor integers in polynomial time. It was invented in 1994 by Peter Shor to solve the problem of finding the prime factors of a given number, N .

An algorithm is essentially a series of steps to solve a problem. However, these steps are limited by the hardware on which the algorithm is being run on.

the experience/knowledge needed. But, if we gave these instructions to a kindergartner, they would be very lost and wouldn’t arrive at an answer. There would probably just be scribbles on the page.

Certain algorithms take much longer on classical computers that obey the laws of macro physics because their hardware may not be able to carry out some of the steps efficiently.

The Bernstein-Vazirani Algorithm was invented by Ethan Bernstein and Umesh Vazirani in 1992. It is a restricted version of the Deutsch–Jozsa algorithm.

Unlike the previous quantum algorithms mentioned, Grover’s algorithm only provides a quadratic speedup in evaluation time for unstructured searches, compared to their exponential speedup. Still, the amplitude amplification trick employed in Grover’s algorithm is extremely useful when trying to ob...

Entanglement is when a pair or group of quantum systems are strongly correlated, giving them the ability to be perfectly in unison, no matter how far apart they are. This means that quantum computers only need to measure 1 qubit and to figure out the value of the other qubit in the pair instantan...

Now imagine if you could find out what the secret number is in one try, no matter its size. That’s exactly what running the Bernstein-Vazirani algorithm on a quantum computer allows you to do.

However, this scenario is unlikely to happen in the near future because we still have a lot more progress to make in lowering quantum noise and quantum decoherence in current quantum computers.

Simon’s problem was one of the first computational problems to prove that a quantum algorithm could solve a problem exponentially faster than a classical algorithm.

The Deutsch-Jozsa Algorithm was to showcase how quantum algorithms can be exponentially faster than any possible deterministic classical algorithm.

When a quantum system is in superposition, it can be a 0 or a 1 or a combination of both, at the same time. This allows a quantum computer to process information at a significantly higher rate than classical computers.

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