What Is a Quantum Computer? Impact on Businesses

01What Is a Quantum Computer?

All the computers we use, from phones to servers in data centers, process information in units called bits. Each bit is either 0 or 1, and computation happens through billions of bits changing rapidly.

Quantum computing, on the other hand, uses the rules of quantum mechanics, which govern the behavior of subatomic particles, for computation. The basic unit here is the qubit, and a qubit behaves fundamentally differently from a classical bit. This difference can open the way to computations that are practically impossible with classical methods for certain problems.

Let us clear up an important misunderstanding from the start: a quantum computer is not a faster version of today's computer. You do not need a quantum computer to read email, open a website or run accounting software, and you never will.

02What Is a Qubit and How Does It Differ from a Bit?

To understand what a qubit is, it is enough to know three concepts. They are deep topics in physics, but their logic can be explained simply.

Superposition

A classical bit is either 0 or 1. A qubit, until it is measured, can be in a state where 0 and 1 exist together with certain probabilities. This is called superposition. When a measurement is made, the qubit lands on a single result, 0 or 1.

Entanglement

Two or more qubits can be linked so that the state of one cannot be described independently of the other. This entanglement lets qubits together represent a much richer state space.

Interference

Quantum algorithms arrange probabilities so that they reinforce or cancel one another like waves. The probability of the right answer is raised and those of wrong answers are lowered. The power of a quantum computer comes not from trying every possibility one by one but from this interference pattern.

03What Is a Quantum Computer Used For?

The honest answer to what a quantum computer is for: it offers an advantage on problems with a certain mathematical structure. The areas researchers focus on most are these:

• Materials and chemistry simulation: The behavior of molecules is quantum by nature; it is a promising area for research into new drugs, batteries and catalysts.
• Optimization: Multivariable problems such as logistics routes, production planning and portfolio allocation are being studied; the practical advantage is still at the research stage.
• Code breaking: Shor's algorithm could break today's widely used public-key encryption methods on a sufficiently large, error-free quantum computer.
• Search problems: Grover's algorithm gives a square-root speedup on unstructured searches.
• Machine learning: The contribution of quantum methods to some learning problems is being researched, but results are still at an early stage.

04What Does a Realistic Timeline Say?

Today's quantum computers work, but they have serious limitations. Qubits are disturbed by the slightest influence from the environment; this is called decoherence. Many systems have to be kept at temperatures close to absolute zero, and computations carry an error margin.

That is why the industry's real goal is to build fault-tolerant quantum computers that correct their own errors. This requires many physical qubits to come together to form a single reliable logical qubit. Experts make different predictions about when this threshold will be reached; it is not possible to give a firm date.

The realistic picture is this: in the coming years quantum computing will move from research labs toward industry, and the first concrete benefits will probably appear in fields such as chemistry and materials science. It is not expected to directly change the daily operations of a small or medium-sized business in the short term.

05Quantum and the Encryption Risk

The most concrete side of quantum computing for businesses is security. Secure connections on the internet, digital signatures and many authentication methods rely on public-key cryptography such as RSA and elliptic curves. A sufficiently powerful quantum computer could break these methods.

That is not yet possible, but there are steps to take today. There is a risk called harvest now, decrypt later: an attacker can record encrypted data today and wait to decrypt it once quantum capability exists. For data that must stay confidential for many years, this is a serious matter.

The methods developed against this are called post-quantum cryptography. The US National Institute of Standards and Technology (NIST) has standardized new algorithms in this area; you can find the details on NIST's post-quantum cryptography page. We covered the subject in technical detail in our post-quantum cryptography article.

06How Do You Access Quantum Computing?

Buying a quantum computer is neither necessary nor practical for a business. Large cloud providers and research companies offer access over the cloud to quantum hardware. Developers can write small quantum circuits with open-source libraries and run them on real hardware or in a simulator.

This access model shows that quantum computing, like edge computing and the cloud, will be consumed as a service. For businesses it means this: instead of building the capability yourself, you will rent it when needed; the real value will lie in defining the problem correctly.

As the table shows, the two technologies are not rivals but complements. In the typical future scenario, classical systems will carry out most of the work and only suitable sub-problems will be sent to the quantum processor, much as graphics processors take on certain computations today.

07What Should Businesses Do Today?

Preparing for the quantum era starts with today's security and infrastructure hygiene. There is no need to panic, but the to-do list can be summarized like this:

1. Identify which data must stay confidential for many years.
2. Ask whether the software and providers you use keep their encryption methods up to date.
3. Apply server, SSL and library updates regularly; new algorithms will arrive with those updates.
4. Prefer a flexible software architecture in which the encryption method can be changed easily.
5. Do not forget today's real threats, such as ransomware attacks; for most businesses they are still the main risk.

08How Does Aurora See This Topic?

At Aurora Yazılım we make it a principle to recommend to businesses the technology that works for them today, without hyping the future. As we describe on our about us page, we have been developing web, e-commerce and sector software for years, and we run every new technology through that filter.

For most businesses today, quantum is not an investment topic but a topic of awareness. What needs doing today is an up-to-date and secure e-commerce infrastructure, a regularly maintained server, and a website monitored under speed and performance management. We described today's real threats in our ransomware guide.

If you want to build a current and sustainable architecture for your business's software needs, you can browse our industry-specific software solutions or consult our team through the contact page.