A deep neural network is a branch of machinelearning that is capable of learning and representingcomplex patterns from a dataset through interconnectedmultiple layers of neurons. This capability makes itapplicable in various fields, such as natural languageprocessing, image processing, and computer vision.Deep learning models show effective performance butface challenges such as complexity and resourcedemands. On the other hand, quantum machine learningalgorithms offer an alternative with potential efficiencycompared to their classical counterparts. This paperproposes a Quantum Recurrent Neural Network (QRNN)for natural language processing tasks, which classify textdata such as parts of speech, named entity recognition,and sentiment analysis. The proposed method utilizesparameterized quantum circuits that contain the tunableparameters. Our approach uses amplitude encodingto represent classical data into quantum states, partialmeasurement for label determination, and ancilla qubitsto transfer the information from the current state to thenext.
A deep neural network is a branch of machinelearning that is capable of learning and representingcomplex patterns from a dataset through interconnectedmultiple layers of neurons. This capability makes itapplicable in various fields, such as natural languageprocessing, image processing, and computer vision.Deep learning models show effective performance butface challenges such as complexity and resourcedemands. On the other hand, quantum machine learningalgorithms offer an alternative with potential efficiencycompared to their classical counterparts. This paperproposes a Quantum Recurrent Neural Network (QRNN)for natural language processing tasks, which classify textdata such as parts of speech, named entity recognition,and sentiment analysis. The proposed method utilizesparameterized quantum circuits that contain the tunableparameters. Our approach uses amplitude encodingto represent classical data into quantum states, partialmeasurement for label determination, and ancilla qubitsto transfer the information from the current state to thenext.
Recurrent neural networks are the foundation of many sequence-to-sequence models in machine learning, such as machine translation and speech synthesis. In contrast, applied quantum computing is in its infancy. Nevertheless there already exist quantum machine learning models such as variational quantum eigensolvers which have been used successfully e.g. in the context of energy minimization tasks. In this work we construct a quantum recurrent neural network (QRNN) with demonstrable performance on non-trivial tasks such as sequence learning and integer digit classification. The QRNN cell is built from parametrized quantum neurons, which, in conjunction with amplitude amplification, create a nonlinear activation of polynomials of its inputs and cell state, and allow the extraction of a probability distribution over predicted classes at each step. To study the model's performance, we provide an implementation in pytorch, which allows the relatively efficient optimization of parametrized quantum circuits with thousands of parameters. We establish a QRNN training setup by benchmarking optimization hyperparameters, and analyse suitable network topologies for simple memorisation and sequence prediction tasks from Elman's seminal paper (1990) on temporal structure learning. We then proceed to evaluate the QRNN on MNIST classification, both by feeding the QRNN each image pixel-by-pixel; and by utilising modern data augmentation as preprocessing step. Finally, we analyse to what extent the unitary nature of the network counteracts the vanishing gradient problem that plagues many existing quantum classifiers and classical RNNs.
The recent developments in the field of deep learning have made Natural Language Processing (NLP) quite useful, but there are still issues of the complexity of computation, energy consumption, and modeling of complex semantics. Representations and optimization techniques that are quantum enhanced are available in quantum computing and provide new possibilities. Hybrid Quantum Neural Networks (HQNNs) combine quantum computational concepts and classical neural networks, allowing the introduction of a new era in intelligent language processing. The chapter provides the basics of quantum computing and neural NLP models and looks at the hybrid methods of semantic representation and learning. The text classification, sentiment analysis, named entity recognition, and machine translation tasks that are fundamental to NLP are examined through a hybrid quantum-neural approach. Such methods as quantum data encoding, quantum feature extraction and hybrid training approaches are described and the issues associated with scalability, noise, and hardware limitations are discussed.
Quantum Natural Language Processing (QNLP) develops natural language processing (NLP) models for deployment on quantum computers. We explore feature and data prototype selection techniques to address challenges posed by encoding high dimensional features. Our study builds quantum circuit classifiers that includes classical feature pre-processing, quantum embedding and quantum model training. The quantum models are built on 4 or 6 qubits and the quantum neural network (QNN) uses the established bricklayer design. We compare the dependence of model performance (in terms of accuracy and F1 scores) on feature length, embedding gates and parameterized unitary design. We compare the performance of quantum machine learning models to classical convolution neural network model (CNN) on binary and multi-class classification tasks using two datasets of synthetic features and labels. The first is the ECP-CANDLE P3B3 dataset a corpus of synthetically generated cancer pathology reports. The second dataset is extracted from well-known benchmark dataset (MADELON) - features are generated with a combination of informative, repeated and uninformative features. Both datasets are used for binary classification and multi-class classification with 3 classes. We observe robust, accurate performance from all models on the binary classification tasks, but multiclass classification is a challenge for the quantum models-there is a notable decrease in accuracy when using 3 classes. Overall the performance is comparable in terms of recall and accuracy between QNNs and CNNs, even with large datasets. These results provide a point of comparison between quantum and classical models on real-world datasets.
Quantum computing with its capacity to compute multiple possibilities at once, and perform some kinds of calculations almost instantly is one leading edge. The integration of QCs and DL undoubtedly represent one such transformative means for improving Natural Language Processing (NLP). By combining the two, this uses quantum principles of superposition and entanglement to make computation faster regarding human language comprehension limitations in classical computing. Deep learning models, specifically neural networks have already made significant improvements over NLP tasks like language translations, sentiment analysis and text generation. Nevertheless, these models also face scalability and computational efficiency issues with huge volumes of data. Quantum computing offers a solution to all this by reducing the time exponentially that it takes to fetch large amounts of language data and running deep learning algorithms. This paper investigates the opportunities that integrating quantum computing and deep learning into NLP practices might unlock. We drafted the fundamentals of quantum computing and why it is a need over classical computing, where we discussed on how quantum beneficial for data processing & optimization of an algorithm. We then explore applications of quantum enhanced deep learning for NLP, with a focus on the impact that training and inference can have on model performance. We demonstrate the utility of this integration by integrating our four SQDs to showcase improvements on diverse NLP tasks through a series of experiments and case studies. We also demonstrate that hybrid quantum-classical approaches allow the combination of traditional ML and quantum-enhanced models, achieving state-of-the-art performance with respect to effectiveness, scalability and precision
Computational methods in drug discovery significantly reduce both time and experimental costs. Nonetheless, certain computational tasks in drug discovery can be daunting with classical computing techniques which can be potentially overcome using quantum computing. A crucial task within this domain involves the functional classification of proteins. However, a challenge lies in adequately representing lengthy protein sequences given the limited number of qubits available in existing noisy quantum computers. We show that protein sequences can be thought of as sentences in natural language processing and can be parsed using the existing Quantum Natural Language framework into parameterized quantum circuits of reasonable qubits, which can be trained to solve various protein-related machine-learning problems. We classify proteins based on their sub-cellular locations—a pivotal task in bioinformatics that is key to understanding biological processes and disease mechanisms. Leveraging the quantum-enhanced processing capabilities, we demonstrate that Quantum Tensor Networks (QTN) can effectively handle the complexity and diversity of protein sequences. We present a detailed methodology that adapts QTN architectures to the nuanced requirements of protein data, supported by comprehensive experimental results. We demonstrate two distinct QTNs, inspired by classical recurrent neural networks (RNN) and convolutional neural networks (CNN), to solve the binary classification task mentioned above. Our top-performing quantum model has achieved a 94% accuracy rate, which is comparable to the performance of a classical model that uses the ESM2 protein language model embeddings. It’s noteworthy that the ESM2 model is extremely large, containing 8 million parameters in its smallest configuration, whereas our best quantum model requires only around 800 parameters. We demonstrate that these hybrid models exhibit promising performance, showcasing their potential to compete with classical models of similar complexity.
Computational methods in drug discovery significantly reduce both time and experimental costs. Nonetheless, certain computational tasks in drug discovery can be daunting with classical computing techniques which can be potentially overcome using quantum computing. A crucial task within this domain involves the functional classification of proteins. However, a challenge lies in adequately representing lengthy protein sequences given the limited number of qubits available in existing noisy quantum computers. We show that protein sequences can be thought of as sentences in natural language processing and can be parsed using the existing Quantum Natural Language framework into parameterized quantum circuits of reasonable qubits, which can be trained to solve various proteinrelated machine-learning problems. We classify proteins based on their sub-cellular locations—a pivotal task in bioinformatics that is key to understanding biological processes and disease mechanisms. Leveraging the quantum-enhanced processing capabilities, we demonstrate that Quantum Tensor Networks (QTN) can effectively handle the complexity and diversity of protein sequences. We present a detailed methodology that adapts QTN architectures to the nuanced requirements of protein data, supported by comprehensive experimental results. We demonstrate two distinct QTNs, inspired by classical recurrent neural networks (RNN) and convolutional neural networks (CNN), to solve the binary classification task mentioned above. Our top-performing quantum model has achieved a 94% accuracy rate, which is comparable to the performance of a classical model that uses the ESM2 protein language model embeddings. It’s noteworthy that the ESM2 model is extremely large, containing 8 million parameters in its smallest configuration, whereas our best quantum model requires only around 800 parameters. We demonstrate that these hybrid models exhibit promising performance, showcasing their potential to compete with classical models of similar complexity.