Quantum Computing – The Basics, Qubits, and Possible Dangers

 

Quantum computing is a revolutionary field that combines the principles of quantum mechanics and computer science to create machines that can perform complex calculations exponentially faster than classical computers. The basic unit of quantum computing is the qubit, a quantum bit, that can represent both 0 and 1 at the same time. This unique property is known as superposition and is the key to the power of quantum computers.

What Are Qubits?

In classical computing, a bit is the smallest unit of information, represented as either a 0 or a 1. However, in quantum computing, a qubit can be in a state of both 0 and 1 at the same time, known as a superposition of states. This means that a qubit can store more information than a classical bit, as it can represent more than just two states.

A qubit can have any proportion or ratio of a 0 or a 1 at any given instant of time. This ratio may be represented using any 2-body quantum system such as a photon which will have some vertical or horizontal polarization.

In addition to superposition, qubits have another unique property known as entanglement. Entanglement is a phenomenon where two qubits become linked in such a way that the state of one qubit is dependent on the state of the other, even if great distances physically separate them. This property allows quantum computers to perform calculations that are practically impossible for classical computers.

How Do Qubits Store Data?

The amount of data that can be stored on qubits depends on the number of qubits used. For example, a single qubit can store two bits of information, as it can be in a superposition of two states. Similarly, two qubits can store four bits of information, as they can be in a superposition of four states, and so on. This exponential increase in storage capacity is what gives quantum computers their enormous computational power. In simpler terms, n qubits can store 2ⁿ values at the same time. Just to put this in perspective, only 20 qubits are needed to store over a million values at once. Even 500 qubits can store a staggering 3*10¹⁵⁰ values at the same time.

To read the qubits, they are simply observed. As a principle of quantum mechanics states, the qubit can be in any state until observed. To get a fixed value, the qubits can simply be observed. For example, a photon could be tested for its horizontal or vertical polarization and at that point, it will only return a 1 or 0 as convenient in computers.

Possible Dangers

Quantum computers pose a potential threat to encryption systems, as they can theoretically break encryption by brute force. Brute force is a method of trying every possible combination until the correct one is found, and with the enormous computational power of quantum computers, this process could be completed much faster than with classical computers.

For example, the RSA encryption system is widely used to secure online transactions and communication. It relies on the difficulty of factoring large numbers, a problem currently very difficult for classical computers. However, quantum computers could potentially solve this problem much faster, rendering the RSA encryption system vulnerable to attack.

Conclusion

Quantum computing is a fascinating and rapidly developing field that has the potential to revolutionize many industries, including finance, pharmaceuticals, and logistics. However, it also poses a potential threat to encryption systems, which are essential for maintaining security in many areas of our lives. As the development of quantum computers progresses, it will be important to address these potential dangers and ensure that security measures are in place to protect our data.