Quantum computing is a complex technique for performing parallel computations, using the physics that govern subatomic particles to replace the simpler transistors in today’s computers.
Quantum computers compute using qubits, the computing units that can be turned on or off or any value in between, rather than the qubits in traditional computers that are on or off, one or zero. The ability of qubits to live in a state in between – called superposition – adds a powerful ability to the computing equation, making quantum computers outperform some types of mathematics.
What does a Quantum Computer do?
With qubits, quantum computers can navigate computations that take longer than classical computers — if they can finish them.
For example, computers today use eight bits to represent any number between the 0 and 255. Thanks to features like superposition, the quantum computer can use eight qubits to represent every number between 0 and 255 at once.
It’s a feature like a parallelism in computing: all possibilities are computed simultaneously rather than sequentially, which provides tremendous acceleration.
So, while classical computer steps through long division calculations one by one to analyze a vast number, the quantum computer can get the answer in one step bubble!
This means that quantum computers can recreate entire fields, such as cryptography, by analyzing today’s impossibly large numbers.
Significant role for small simulations
It could just be the beginning. Some experts believe that quantum computers will push the boundaries that now hamper simulations in chemistry, materials science, and anything that involves worlds built on the Nanoscale building blocks of quantum mechanics.
Quantum computers can extend the life of semiconductors by helping engineers create more accurate simulations of the quantum effects they are beginning to find in today’s smallest transistors.
Experts say that quantum computers will not eventually replace classical computers but rather complement them. Some speculate that quantum computers will be used as accelerators just as GPUs speed up today’s computers.
How does quantum computing work?
Don’t expect to build your quantum computer like a DIY computer with parts scanned from discount boxes at your local electronics store.
The range of systems in operation today typically requires cooling that creates working environments north of absolute zero. In addition, they need arctic computing to handle the fragile quantum states that power these systems.
In a sign of how difficult it is to build a quantum computer, one of the prototypes suspends an atom between two lasers to create a qubit. Try it in your home workshop!
Quantum computing takes the Nano scale of Hercules’s muscles to create entanglement. This occurs when two or more qubits exist in a single quantum state, a state sometimes measured in electromagnetic waves that are no more than one millimeter wide.
Ramp up that wave with a lot of energy hair, and you’ll lose tangles, overlays, or both. The result is a tumultuous state called DE coherence, which in quantum computing is the equivalent of the blue screen of death.
What are the prospects for quantum computing?
Many companies like Alibaba, Google, Honeywell, IBM, IonQ, and Xanadu are working on early versions of quantum computers today.
Today they offer dozens of qubits. But qubits can be noisy, which sometimes makes them unreliable. Systems need tens or hundreds of the thousands of qubits to handle real-world problems reliably.
Experts believe that it may be two decades before we reach the era of high precision when quantum computers are beneficial.
Why do we want it?
The promise of developing a quantum computer complex enough to implement the Shor algorithm for large numbers was the primary impetus for the development of the field of quantum computation. To create a broader view of quantum computers, it is essential to understand that they will likely provide massive acceleration for only specific types of problems. Researchers are working to understand the relevant issues for quantum acceleration processes and develop algorithms to demonstrate them. Overall, quantum computers are believed to be of great help in solving problems related to optimization, which play vital roles in everything from defense to financial trading.
There are also many applications of qubit systems that are not related to computing or simulation and constitute active areas of research but are outside the scope of this overview.
Two of the most prominent areas are
- Quantum sensing and metrology take advantage of the extreme sensitivity of qubits to the environment to achieve sensing beyond the classical limit of shot noise.
- Quantum networks and communications may lead to revolutionary ways of exchanging information.