What is Quantum Machine Learning?

Parth Shukla 11 Jul, 2024
7 min read


Machine learning is one of the trending topics in the current industry and business scenarios, where almost all companies and businesses want to integrate machine learning applications into their working mechanisms and work environments. It is growing daily, and its application is enhancing time by time, where many scientists and students are working on the research of the same.

Quantum computing has been a hot topic recently and has more comprehensive applications than regular classical computers. This article will discuss quantum machine learning, which integrates Quantum algorithms and machine learning. We will discuss its working, application, and some of the advantages and disadvantages associated with it. This article will help one to understand the new topic and will help to plan and learn accordingly.So at the end of this article you will get complete understanding about the quantum computing and machine learning.

Before directly jumping to the concept, let us discuss quantum computing first.

Learning Objectives

This article will help one to:

  • To understand the core idea behind quantum computing
  • Difference between the three types
  • How it works?
  • Applications of the machine learning
  • Answer interview questions related to quantum machine learning

This article was published as a part of the Data Science Blogathon.

What is Quantum Computing?

Quantum computing is a branch of computer science that uses the quantum physics concepts to solve problems and statements that regular or classical computers can’t solve. Like the bits in the classical computers, the quantum computer uses qubits capable of solving complex problems and passing the information to each other.


Here, qubits surpass standard bits found in classical computers in terms of sophistication and data storage capabilities. Additionally, qubits can be conceptualized as specific waves in Quantum algorithms physics responsible for containing and transmitting information and data.

It is better to compare classical and quantum machine learning to get a clear idea. However, before comparing them, let us compare normal programming and machine learning.

Quantum Advantage in Machine Learning

  • Enhanced Optimization: Quantum algorithms can solve certain optimization problems, such as finding the global minimum of a complex function, more efficiently than classical algorithms.
  • Improved Pattern Recognition: Quantum systems can exploit quantum mechanical phenomena, like superposition and entanglement, to identify patterns in data more accurately and efficiently.
  • Enhanced Simulation and Modeling: Quantum computers can simulate complex quantum systems, which is crucial for applications like material science, drug discovery, and climate modeling.
  • Faster Data Processing: For some data processing and Machine learning models applications, like database searches and machine learning model training, quantum algorithms may provide appreciable speedups.

Challenges and Limitations

  • Hardware Limitations: Current quantum computers are still in the early stages of development and face challenges such as limited qubit count, error rates, and scalability.
  • Algorithm Development: Designing efficient quantum machine learning algorithms that can outperform classical methods is an active area of research.
  • Data Availability: The successful application of quantum machine learning often requires access to large, high-quality datasets, which can be a limitation in certain domains.
  • Integration with Classical Systems: Integrating quantum ML with traditional computing systems and existing infrastructure is an ongoing challenge.

The possible uses of quantum machine learning models are anticipated to grow as quantum technology develops further, providing fresh chances for improved problem-solving and creative solutions in a range of fields and sectors.

Types of Quantum Machine Learning

Quantum machine learning combines quantum algorithms and machine learning techniques to improve the speed and accuracy of learning from data. It uses quantum physics and quantum computers to enhance the capabilities of machine learning. There are different types of quantum machine learning, such as:

Quantum Neural Networks (QNN)

These are neural networks that operate on quantum logic gates and qubits, which are the basic units of quantum information. QNNs can leverage quantum phenomena such as superposition and entanglement, enabling qubits to simultaneously exist in multiple states and exhibit correlation with each other. QNNs can perform faster and more efficient learning than classical neural networks.

Quantum Support Vector Machines (QSVM)

These are support vector machine learning models that use quantum algorithms to find the optimal hyperplane that separates the data points into different classes. QSVMs can use quantum speedup and quantum parallelism, which enable quantum computers to perform multiple operations simultaneously and solve complex problems faster than classical computers.

Quantum Reinforcement Learning (QRL)

These are reinforcement learning algorithms that use quantum agents and quantum environments to learn optimal policies and actions. QRL can use quantum resources and quantum feedback, which provide quantum agents with more information and better rewards than classical agents.

Applications of Quantum Computing

1. More Faster Algorithms

With the help of quantum computing, we can make the algorithm’s training on more enormous datasets faster and more efficient. The QML algorithms can be super faster compared to classical machine learning where qubits will play major role.

2. Solving Complex Data Patterns

Quantum computing can assist in solving complex data patterns that cannot be addressed by classical machine learning and deep learning algorithms. Very complicated datasets where data correlations and patterns are not recognisable and solvable, the QML can make it possible.

3. Develop Advanced Algorithms

Quantum computing, with the integration of machine learning can help build and design more advanced machine learning algorithms. Advanced algorithms integrated with quantum computing can solve more problems in less times with greater accuracies.

4. Advancement in Reinforcement Learning

Reinforcement learning stands to benefit significantly from the incorporation of quantum computing concepts. Novel concepts within reinforcement learning can be developed and enhanced through quantum machine learning utilizing qubits.

5. Advanced Computer Vision

Quantum machine learning can also help advance the computer vision application and make the existing deep learning algorithms quicker and more efficient. With the help of quantum machine learning, we can develop more advanced and accurate image segmentation and processing applications.

Classical Programs vs. Machine Learning

As we might think that machine learning is the same as classical programming, it is wrong. In classical programming, the input is taken, preprocessed, and then directed to the output is given. Here we have pre-defined functions and rules where we take the information, apply functions and regulations to it, and whatever result we get, we display it as an output of the program.

ML is very different from classical programming, where the input is first divided into two parts, training and testing. Then the training data is fed to the ML program where no pre-defined function exists in the rules. The model learns from the training data autonomously, and after training, it undergoes testing with the actual values from the testing data. The loss function aids in identifying the errors and mistakes made by our model.

As we saw that machine learning is entirely different than the classical programming, now let us compare.

Machine Learning vs. Quantum Machine Learning

As we discussed that machine learning is a set of program that takes the data as input, preprocess it, and learn from it. Then, the testing data is used to evaluate the model, and the model’s loss is calculated.

Quantum Machine Learning

We take the ideas of atoms and molecules from quantum physics and train the model on training data rather than the bits level. In quantum ML, we utilize qubits, which are far more advanced than regular bits. We also test the model on the testing data after its training, calculate the loss function, and try to minimize the same.

What Exactly is Quantum Machine Learning?

Now as we have an idea about classical programming, machine learning, and quantum computing, it is the best time to learn about QML. This process entails integrating classical machine learning with quantum computing, leveraging quantum computing to apply ML concepts and techniques instead of relying solely on classical computing and programs.

Quantum Machine Learning

As the standard or classical computer works with bits with either the value 0 or 1, the same quantum computers have qubits or quantum bits, which also store the data. Still, it leverages the principle of superposition, which means that, unlike the classical bits, the qubit can be in multiple states simultaneously.

To understand the principle of superposition, let us take an example. We have a coin. We toss it, and now it can give us a tail or a head. Before launching the cos’s or while the coin is flipping in the air, we can’t say it’s in a heads or tails state. That means it is partially in heads and tails, according to the person’s view. Here, we refer to the principle known as the superposition of the coin, where the coin can exist in multiple states simultaneously.


This article discussed quantum machine learning and how it differs from classical programming and machine learning. This article will help one understand the concept, its core idea, and how it can be helpful in the future.

Hope you like the article and get understanding about the quantum machine learning and its applications its impacts, also about the quantum computing and machine learning.

Key Takeaways

  • In classical programming, we just take the input, process it and display the output with the help of pre-defined functions.
  • Machine learning is an advanced approach to classical programming where the model learns from the data and results from an output.
  • In QML, we use ML with quantum computing concepts, where we employ qubits instead of bits to train the model.
  • QML can help in making the existing algorithms faster, developing new algorithms, and solving more complex algorithms.

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Frequently Asked Questions?

Q1. Is quantum machine learning the future?

A. Quantum machine learning holds significant potential for solving complex problems that classical computers struggle with. While still in its early stages, it has the potential to revolutionize certain areas of machine learning and optimization. However, its widespread adoption as the future of machine learning depends on further advancements in quantum technology and algorithms.

Q2. Can quantum computing be used for machine learning?

A. Yes, quantum computing can be used for machine learning tasks. Quantum computers have the potential to perform certain calculations exponentially faster than classical computers, which could lead to advancements in training complex models, optimization problems, and pattern recognition tasks.

Q3. Who is the father of quantum machine learning?

A. The term “quantum machine learning” does not have a single father figure, as it is a field that has evolved from the intersection of quantum computing and machine learning. However, some prominent researchers and pioneers in this field include Seth Lloyd, Peter Wittek, and Maria Schuld.

Q4. What is the future of quantum machine learning?

A. QML: quantum computing meets machine learning. It’s like having a super-powered brain for super-tough problems. Future looks bright, but building the hardware and training the brain are still works in progress.

Parth Shukla 11 Jul, 2024

UG (PE) @PDEU | 25+ Published Articles on Data Science | Data Science Intern & Freelancer | Amazon ML Summer School '22 | AI/ML/DL Enthusiast | Reach Out @portfolio.parthshukla.live

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