Quantum Natural Language Processing (QNLP) is a burgeoning field that merges artificial intelligence (AI) and quantum computing. The rise of quantum computers and large language models (LLMs) has elevated the status of natural language processing (NLP), leading to new AI model applications, improvements, and challenges. QNLP has seen early experiments using techniques like word embeddings, sequential models, attention, and grammatical parsing. Quantum theory has also contributed to the understanding of uncertainty and intelligence in AI systems. The application of quantum theory in language operations offers new forms of mathematical modeling, computation, and communication.
What is Quantum Natural Language Processing (QNLP) and its Current State?
Quantum Natural Language Processing (QNLP) is a rapidly evolving field that combines the advancements in artificial intelligence (AI) and quantum computing. The availability of quantum computers and the development of large language models (LLMs) have significantly raised the profile of natural language processing (NLP). This has led to AI models being deployed in new ways, leading to improvements and efficiencies, but also mistakes and concerns. As a result, there is a high demand for improvements in AI, with a renewed focus on reliability and trust.
QNLP has seen several early proposals and experiments, with techniques such as word embeddings, sequential models, attention, and grammatical parsing being used in quantum language processing. A new quantum design for the basic task of text encoding, which represents a string of characters in memory, has been introduced. This design has not been addressed in detail before, and it represents a significant advancement in the field.
Quantum theory has also contributed to the challenging questions of “What is uncertainty?” and “What is intelligence?” These questions are taking on fresh urgency with artificial systems. The paper also considers some of the ways facts are conceptualized and presented in language. In particular, it argues that the problem of hallucinations arises through a basic misunderstanding: language expresses any number of plausible hypotheses, only a few of which become actual. This distinction is ignored in classical mechanics but is present in quantum mechanics.
How is Quantum Theory Applied in Language Operations?
Quantum theory offers new forms of mathematical modeling, computation, and communication. Mathematical models for language operations, motivated explicitly by quantum theory, have been used in information retrieval, logic and disambiguation, and language composition. Similar models have been developed in many social sciences and demonstrated successful results over classical alternatives long before any such models were implemented and run on quantum computers.
More abstractly, entire classes of quantum machine learning (ML) models have been theoretically shown to have more expressive power than comparable classical models. Running basic NLP algorithms on quantum has become possible only in the last few years, with early-stage results reported by several researchers.
What are the Basics of Quantum Computing in the NISQ Era?
In early 2024, quantum computers are real and in regular use, and quantum runtime is offered as-a-service by many companies via the internet cloud. The development process involves specifying a register of qubits and saying what logic gates and measurements should be performed on these qubits.
The key features that distinguish quantum from classical computers are superposition and entanglement. Superposition can be realized in a single qubit, the state α0β1 is a superposition of the states 0 and 1, where α and β are complex numbers.
How is Quantum Computing Applied in Language Processing?
The paper provides a detailed example of how quantum gates and circuits might be used for representing the sequences of characters that make natural language texts. This gives a glimpse of some of the wonder and some of the challenges of quantum computing. The main body of the paper surveys ways in which other aspects of language processing have already been modeled on quantum computers, including embedding vectors, sequences, attention, and grammatical structure.
Finally, the paper discusses the challenges of choosing and distinguishing between the hypothetical and the actual. This has taken on fresh urgency in AI systems for fact-checking to avoid mistaking hallucinations for assertions. The paper notes that language models are designed to produce both hypothetical and actual statements, and that quantum mechanics is a better starting point than classical mechanics for modeling this.
What are the Future Directions for QNLP?
The paper serves as an introduction to the landscape of QNLP for those interested in language processing and quantum computing. It provides a snapshot of where quantum NLP has got to at this stage of the NISQ era. The challenges and opportunities in the field are also discussed, with a focus on the need for improved reliability and trust in AI systems. The paper also highlights the potential of quantum mechanics as a better starting point than classical mechanics for modeling the distinction between hypothetical and actual statements in language.
Publication details: “Natural Language, AI, and Quantum Computing in 2024: Research
Ingredients and Directions in QNLP”
Publication Date: 2024-03-28
Authors: Dominic Widdows, Willie Aboumrad, Dohun Kim, Sayonee Ray, et al.
Source: arXiv (Cornell University)
DOI: https://doi.org/10.48550/arxiv.2403.19758
