The ever-emerging field of computer science has led us to the early age of quantum computing. Considering it a major evolution in computer science, quantum computing brings an extraordinary ability to process data and information. While the current generation of computers is sufficiently filling the requirement, this field is now about to open a wide room for computing at a quantum level.

Quantum computing is also said to be a big threat to blockchain and cryptocurrency security. So what is the buzz around quantum computing, and what risk is it creating for blockchains? Let’s understand all about it in this article.

## What is Quantum Computing?

Quantum computing is a new field of processing information using the principles of quantum mechanics. It stands to exceed the computational power billions of times faster than the current generation of computers.

The capability of quantum computers is far beyond the classic computers or even supercomputers currently available. For instance, an experiment from Google revealed that its early-developed quantum computer performed a complex computation in just 200 seconds, which would take thousands of years for normal computers.

The core difference between a normal computer and a quantum computer is their computational capability. All the normal computers used at home and in offices use ‘bits’ as data storage units and involve binary code for reading and writing information. The information and data are managed using two states, 0 and 1, which both are used to send high and low voltage signals for producing output.

Quantum computers, on the other hand, store information in quantum bits, aka ‘qubits.’ While a normal computer involves just 0 and 1, as in yes or no conditions, qubits are floating point states with tree-like states. This enables producing output way faster and in massive quantity that is not achievable by normal computers.

## How Quantum Computing Functions?

The functionality of quantum computers is based on two aspects of quantum physics: Superposition and entanglement.

**Superposition**: It is a principle of quantum computing that allows qubits to store information in a combined form of 0 and 1 rather than traditional computing, which stores either 0 or 1 at a time. This enables the sequential storing of information in a single state.

**Entanglement: **The entanglement enables qubits to be connected with others. In this realm, the state of one qubit can influence other qubits’ states without any distance limit. This improves and leads information processing speed to new heights.

Both these novel principles enable quantum computers to reach a certain computational capacity that normal computers can not.

## Blockchain Vs. Quantum Computing

While the premise of quantum computing is to expand computational capabilities beyond imagination, it poses an apparent risk for the existing blockchain and cryptocurrency industry. Several studies have proved that quantum computers can easily break encryption used in blockchain. So, will it completely erase the existence of blockchain and cryptocurrency? Let’s understand.

### Is Quantum Computing a Threat to Blockchain Security?

As a superior computational system, quantum computing can decrypt the RSA encryption to secure Bitcoin and other blockchain networks. This compromises the security of Bitcoin transactions and could even allow changes to the transferred information.

Google’s experiment revealed that quantum computing could take fewer minutes to execute a complex process. It poses risks for blockchain security which will be outdated after the emergence of quantum computers. The quantum computer used by Google in that test was also an initial development, and the actual system could be even more powerful.

Following are some examples of how quantum computing could risk blockchain security;

**Breaking Encryption**

Most of the blockchain uses RSA (Rivests-Shamir-Adlemad) or ECC (Elliptic Curve Cryptography) encryption algorithms, which are vulnerable to quantum commuting. Unlike normal computers, which are used to build these encryption protocols, quantum computers could easily achieve its counter using high-speed computation.

**Private Key Exploring**

The improved computing capacity will make it easy to guess private keys just by finding public keys. Despite several quadrillions variations of the private keys in the ECDSA (Elliptic Curve Digital Signature Algorithm) directory, finding a private key for a specific public key will take hours or even minutes.

**Blockchain 51% Attack**

Quantum computing could help in achieving significantly higher hash power for creating blocks. This would open a window for frequent 51% attacks on existing blockchains. Quantum computers could also bring unfair advantages for miners or validators in producing blocks more frequently than others.

**Centralization**

One of the core values of blockchain technology is decentralization. Quantum computers are capable of taking over most of the hash power of a blockchain network and can control the blockchain as one entity. This also puts the blockchain network at risk of being modified, allowing double spending and other illegitimate activities.

However, some experts predict that it will take up to two decades for quantum computing to be fully functional. In the meantime, Bitcoin and blockchain technology will be more advanced in terms of security. Several privacy-preserving innovations, such as zk-SNARKs, have already been launched for blockchain security, and they are frequently updated with newer advancements. In addition, the cost of operating quantum computing to decrypt blockchain might be so high that even riches could not afford it.

## How Quantum Computing and Blockchain Intersect

The above-mentioned negative aspects of Quantum computing are disastrous for blockchain, but it could also introduce ground-breaking improvements. Both these technologies are emerging in the field of data science. Quantum computing is setting a foundation for newer innovations, while blockchain is an application of DLT technology.

The intersection of both could craft various novel data applications such as Quantum Blockchain. Let’s explore some potential solutions that blockchain and quantum computing could bring to the table.

### Quantum Blockchain

Several developers are currently researching the idea of quantum blockchains. This novel concept of blockchain will use quantum mechanics for data protection and security. The function of entanglement in quantum computing will enable quantum blockchains to reach a new level of immutability. These blockchains will have the typical features of a decentralized, encrypted, and secured DLT while inheriting the fundamental functionalities of quantum computing.

### Quantum Cryptography

Currently, the cryptography method uses random selections of integers in the key generation process. Such a randomization technique has its limitations and is inefficient in customized use cases. Quantum computing could take it to the next level with its advanced computational capabilities.

### Quantum Key Distribution

The current blockchains can be updated with the quantum key distribution method, where any attempt to read the encrypted key results in state disruption. This method of encrypting keys involves quantum computing, which unlocks generational advancements in transferring information. It could significantly improve the security of both parties when exchanging keys.

The above-listed points are just a glance into the future of blockchain and quantum computing. This combination could go far beyond that and bring numerous advantages by enhancing blockchain technology from its fundamentals.

## How to Reduce the Impact of Quantum Computing on Blockchain?

Quantum computing can severely impact the security of blockchain and cryptocurrency. Even the first generation of Quantum computers could solve the encryption of current blockchain networks like Bitcoin and Ethereum.

However, as this new-age technology has yet to come into existence, steps must be taken to reduce its impact on blockchain security. Some of them are as follows;

**Quantum Resistant Algorithms**

Implementing lattice and hash-based cryptographic algorithms would prevent blockchain from quantum computer attacks. Blockchain companies and service providers could experiment with advanced security measures to face potential attacks from quantum computing.

**Quantum Cryptography Models**

Blockchain applications developed using quantum cryptography would provide a layer of security to cryptocurrencies. A novel example is Quantum Key Distribution (QKD), which uses quantum computing for private and public key distribution.

**Quantum Blockchain Development**

The development of Quantum blockchain will use quantum cryptography at its core. This novel development will not only protect against threats of quantum attacks but open a new security primitive for blockchain.

## Final Words

Whenever a new technology enters the market, it is heavily criticized based on negative and sometimes even positive impacts. The field of quantum computing has a brighter side than it is considered a threat to the blockchain industry. This evolutionary field stands a chance to reshape how data and information work in every aspect.

By putting the overprotective throughs of quantum computing and blockchain in place, its safe and successful integration could benefit different sectors. Quantum computing could also enable a deeper dive into subjects – such as medicine, physics, or engineering – to understand and improve its applicability.

## FAQs

**Can quantum computing solve cryptography? **

It’s too early to think about such an incident, but a bad actor with sufficient quantum computing capacity could solve the cryptography.

**Is it possible to hack blockchain using quantum computing?**

Currently, it seems possible, but until the final implementation of quantum computing happens, blockchain security will be advanced and updated to counter quantum attacks.

**What is quantum blockchain? **

The quantum blockchain is the application created by combining blockchain and quantum computing features. It is a novel concept of storing and processing data using a safe, secure, and efficient method.