In the past 20-25 years, our development towards computers is at an exponential rate
Today, the CPU in our phone is much faster than those of computers 10 years ago
But humanity’s technological development in Silicon is going to reach a physical limit because of quantum effects.
And that’s one of the major reasons for developing a different form of computational power, which is “quantum computer”.
So, let’s go ahead and discuss everything related to Quantum Computing in today’s video of DiscoverZen.
A quantum computer harnesses some of the almost-mystical phenomena of quantum mechanics to deliver huge leaps forward in processing power.
Quantum machines promise to outstrip even the most capable of today’s—and tomorrow’s—supercomputers.
They won’t wipe out conventional computers, though.
Using a classical machine will still be the easiest and most economical solution for tackling most problems.
But quantum computers promise to power exciting advances in various fields, from materials science to pharmaceuticals research.
Companies are already experimenting with them to develop things like lighter and more powerful batteries for electric cars, and to help create novel drugs.
Today's computers use bits - a stream of electrical or optical pulses representing 1s or 0s.
Everything from your tweets and e-mails to your Spotify songs and YouTube videos are essentially long strings of these binary digits.
Quantum computers, on the other hand, use qubits, which are typically subatomic particles such as electrons or photons.
Generating and managing qubits is a scientific and engineering challenge.
Some companies, such as IBM, Google, and Rigetti Computing, use superconducting circuits cooled to temperatures colder than deep space.
Others, like IonQ, trap individual atoms in electromagnetic fields on a silicon chip in ultra-high-vacuum chambers.
In both cases, the goal is to isolate the qubits in a controlled quantum state.
Qubits have some quirky quantum properties that mean a connected group of them can provide way more processing power than the same number of binary bits.
One of those properties is known as superposition and another is called entanglement.
So what is superposition?
Qubits can represent numerous possible combinations of 1 and 0 at the same time, that is, an ability of a quantum system to be in multiple states at the same time.
And this is superposition.
To put qubits into superposition, researchers manipulate them using precision lasers or microwave beams.
Thanks to this counterintuitive phenomenon, a quantum computer with several qubits in superposition can crunch through a vast number of potential outcomes simultaneously.
The final result of a calculation emerges only once the qubits are measured, which immediately causes their quantum state to “collapse” to either 1 or 0.
Now, what about entanglement?
As they also possess a significant performance improvement in quantum computers.
Here’s an explanation: If the pairs of qubits are “entangled,” it means that the two members of a pair exist in a single quantum state.
Changing the state of one of the qubits will instantaneously change the state of the other one in a predictable way.
This works even if they are separated by light-years.
Currently, qubits based on a particle’s spin direction must be positioned about 15 nanometers apart — any more, and their entanglement fails.
But quantum engineer Andrea Morello of the University of New South Wales in Australia and his colleagues now claim to have designed qubits that can be separated by up to 500 nanometers.
Nobody really knows quite how or why entanglement works.
It even baffled Einstein, who famously described it as “spooky action at a distance.”
But it’s key to the power of quantum computers.
In a conventional computer, doubling the number of bits doubles its processing power.
And thanks to entanglement, adding extra qubits to a quantum machine produces an exponential increase in its number-crunching ability.
So that’s a good thing.
The bad thing is that quantum machines are way more error-prone than classical computers because of decoherence.
Decoherence is a phenomenon where the interaction of qubits with their environment in ways that cause their quantum behavior to decay and ultimately disappear.
Their quantum state is extremely fragile.
The slightest vibration or change in temperature—disturbances, known as “noise” in quantum theory—can cause them to tumble out of superposition before their job has been properly done.
That’s why researchers do their best to protect qubits from the outside world in those supercooled fridges and vacuum chambers.
But despite their efforts, noise still causes lots of errors to creep into calculations.
Smart quantum algorithms can compensate for some of these, and adding more qubits also helps.
However, it will likely take thousands of standard qubits to create a single, highly reliable one, known as a “logical” qubit.
And because of so many variables involved in the quantum world, researchers haven’t been able to generate more than 128 standard qubits In theory, a 300-qubit quantum computer could perform more calculations at once than there are atoms in the observable universe.
And Big tech giants like IBM promised a 1000-qubit computer by 2023.
Currently, the most common quantum computer which is tested by most big companies has just shy of 53 qubits.
So, what are some of the useful things a Quantum Computer can do?
While the power of quantum computing is impressive, it does not mean that existing software simply runs a billion times faster.
Rather, quantum computers have certain types of problems that they are good at solving, and those which they aren’t.
A primary application for quantum computing is artificial intelligence (AI).
AI is based on the principle of learning from experience, becoming more accurate as feedback is given until the computer program appears to exhibit “intelligence.”
This feedback is based on calculating the probabilities for many possible choices, therefore AI is an ideal candidate for quantum computation.
It promises to disrupt every industry, from automotive to medicine, and it’s been said AI will be to the twenty-first century what electricity was to the twentieth.
For example, Lockheed Martin plans to use its D-Wave quantum computer to test autopilot software that is currently too complex for classical computers, and Google is using a quantum computer to design software that can distinguish cars from landmarks.
We have already reached the point where AI is creating more AI, and so its importance will rapidly escalate.
Another application can be precision modeling of molecular interactions, finding the optimum configurations for chemical reactions.
Such “quantum chemistry” is so complex that only the simplest molecules can be analyzed by today’s digital computers.
Chemical reactions are quantum in nature as they form highly entangled quantum superposition states.
But fully-developed quantum computers would not have any difficulty evaluating even the most complex processes.
Google has already made forays in this field by simulating the energy of hydrogen molecules.
The implication of this is more efficient products, from solar cells to pharmaceutical drugs, and especially fertilizer production.
Since fertilizer accounts for 2 percent of global energy usage, the consequences for energy and the environment would be profound.
Another important use of quantum computers can be in Cryptography.
Most online security currently depends on the difficulty of factoring large numbers into primes.
While this can presently be accomplished by using digital computers to search through every possible factor, the immense time required makes “cracking the code” expensive and impractical.
Quantum computers can perform such factoring exponentially more efficiently than digital computers, meaning such security methods will soon become obsolete.
Any form of encryption will be a cakewalk for quantum computers to go over, but if we can try and encrypt using Quantum computers by some new techniques, it can be beneficial for any form of online security.
Now let’s look at some of the recent development towards Quantum computing.
A team of researchers from multiple institutions in China claim to have achieved quantum supremacy (or quantum advantage) with their quantum computer called ‘Jiuzhang’, which was able to complete a task 100 trillion times faster than the world’s fastest supercomputers.
The race to build the first quantum computer capable of achieving quantum advantage has been heated in recent years, with Google claiming a success in 2019 when its prototype completed a calculation in minutes that its researchers estimated would have taken a supercomputer 10,000 years.
That met the definition for quantum advantage — the moment a quantum computer carries out a task that would be otherwise impossible for a conventional computer.
The Chinese quantum computer makes its calculations (limited to particular questions about the behavior of light particles) using optical circuits.
Google's device, Sycamore, uses superconducting materials on a chip and more nearly resembles the basic structure of classical computers.
Neither would be particularly useful on its own as a computer, and the Chinese device was built to solve just one type of problem.
Now, in theory, we can say that this Chinese quantum computing is way out of the league but since it’s designed to solve one thing only, we aren’t quite convinced that it will be claimed as the Fastest Quantum Computer.
So, this is all about the basics of Quantum Computers.
Now let’s discuss “What if we built a Time Travel machine?”
Well, that sounds like a different video to speculate and investigate on DiscoverZen.