NTU College of Computing and Data Science (CCDS) latest news in 2026 puts a fundamental question in front of students: if AI can generate code, what should a computing graduate still know how to do? In November, the college hosted a high-profile discussion about world models and the future of AI; in October, two faculty members received EMNLP 2026 Best Paper Awards for language-model research. It also announced new academic research guidance and is preparing a 13 November workshop on computing education in the AI age. Applicants looking at NTU Computer Science, Data Science and Artificial Intelligence, Computer Engineering or Artificial Intelligence and Society should connect these developments to actual curriculum and admissions requirements.
The practical admission details come first. NTU publishes different 2027 undergraduate application windows for A-Level, polytechnic, IB, NUS High School and international qualifications. The college lists multiple four-year computing programmes, including Data Science and Artificial Intelligence, a degree offered jointly with NTU’s School of Physical and Mathematical Sciences. The right decision depends on the mathematical and technical demands, the student’s interests and the approved entry requirements. This independent eduKateSingapore guide was checked 11 November 2026.
Quick answers: NTU CCDS in November 2026
- 3 November talk, 6 November report: AI researcher Yann LeCun presented the case for world models beyond current language models; NTU faculty then published perspectives, including meaningful disagreements about language and reinforcement learning.
- 30 October report: CCDS professors Jordan Boyd-Graber and Luu Anh Tuan received both Best Paper Awards at EMNLP 2026, for work on human-versus-AI answering strategies and improvements to language-model computation.
- 28 October report: Associate Professor Stefano Albrecht published Becoming an AI Researcher, a book about doctoral research processes, integrity and developing useful problems, rather than a new undergraduate textbook.
- 13 November event: an International Workshop on Computing Education in the AI Age is scheduled at NTU. As of this article’s 11 November date, it has not yet happened.
- CCDS degrees: the official NTU admissions list includes Computer Science, Computer Engineering, Data Science and Artificial Intelligence and Artificial Intelligence and Society, plus defined double-degree and interdisciplinary options.
- 2027 admission windows: local polytechnic 1–21 February 2027; IB 15 October 2026–19 March 2027; Singapore A-Level results release–19 March 2027. Other groups differ.
- 2026/27 tuition: NTU lists S$8,300 annual subsidised tuition for eligible Singapore citizens in most standard undergraduate programmes, subject to programme exceptions and the correct cohort.
- Student advice: learn algorithms, mathematics, systems, data evaluation and ethical judgement rather than assuming prompt-writing alone is a computing degree.
What happened at NTU on 3 November 2026?
The college reported that Yann LeCun gave a lecture on “World Models: Enabling the Next AI Revolution” on 3 November 2026 at NTU. His argument, summarised by the university on 6 November, was that large language models have limitations when they try to acquire an understanding of the physical world from text alone.
LeCun argued that AI may need internal representations of how an environment works, allowing systems to anticipate outcomes and plan actions. Such systems are often called world models. A model of the world can help predict what may happen when an agent pushes an object, changes course or interacts with an environment.
That does not mean every world model has already achieved reliable human-like reasoning. Different research approaches use the term in different ways, and there is active disagreement over how they should be trained and combined with other methods.
The NTU CCDS report is unusually useful because it includes perspectives from faculty who did not simply repeat the speaker’s view. That is a strong example for students of how scientific ideas should be debated.
What is a world model?
Imagine a robot moving through a room. It sees a chair, a closed door and an obstacle. A simple navigation system might react to each sensor reading, while a more sophisticated system can build an internal representation of the space, predict how moving will change the scene and plan a route.
A world model may represent how objects move, how actions change the environment or how observations relate to hidden states. It can help a learning system choose actions more efficiently, but the quality of the prediction depends on the data, assumptions and model.
In realistic environments, the model may be wrong or incomplete. Sensors can fail; people may behave unpredictably; objects may not match expectations. Good agents need ways to recognise uncertainty and recover from mistakes.
The educational lesson is that intelligence involves more than generating plausible sentences. It also involves perception, action, feedback and the ability to test predictions.
Why did NTU faculty disagree about reinforcement learning?
In the 6 November account, Associate Professor Stefano Albrecht argued that reinforcement learning remains a fundamental principle for decision-making under uncertainty. A world model may describe an environment, but an agent still needs a method for choosing actions and learning which behaviours lead to desirable outcomes.
Reinforcement learning studies how actions, rewards and experiences can influence a system’s behaviour. The method has limitations and challenges, but it does not become irrelevant simply because world modelling improves.
Consider a robot deciding how to move an object. A world model may predict that pushing too hard causes the object to fall. The agent must still decide which action to take, balancing efficiency, safety and uncertainty. Planning and reinforcement learning can be complementary rather than mutually exclusive.
A student should see this scientific disagreement as useful evidence of an open research question, not as proof that one school of thought has already won.
Why did another NTU researcher defend language?
Professor Jordan Boyd-Graber argued that language remains an important way humans store knowledge and interact with one another. Current language models have limitations, yet language itself is central to human civilisation and communication.
This is another reason to avoid simplistic headlines such as “language models are finished”. A technology can have shortcomings and still remain useful for scientific and commercial tasks. A different model architecture may complement existing tools rather than replace them overnight.
In software development, natural-language instructions help people explain a problem, but reliable implementation still requires formal requirements, tests and reasoning. A student who understands both human communication and computational systems is better prepared than one who treats them as opposites.
What should a future Computer Science student conclude?
The most useful takeaway is that foundations outlast product names. A popular model architecture may change, but probability, optimisation, algorithms, systems and learning theory remain useful ways to evaluate new ideas.
A student should learn why an algorithm produces a result, how to test it, what data limitations matter and how to design a program that remains reliable when operating conditions change. These habits are valuable whether an employer uses language models, world models or a combination.
A strong computing education encourages students to ask what remains unknown. Scientific progress requires challenge and verification, not the ability to recite the most confident speaker’s opinion.
30 October: NTU CCDS wins two EMNLP Best Paper Awards
NTU’s 30 October report describes awards received by Professor Jordan Boyd-Graber and Associate Professor Luu Anh Tuan at the 2026 Conference on Empirical Methods in Natural Language Processing.
The first recognised work, “DiscoTrace: Representing and Comparing Answering Strategies of Humans and LLMs in Information-Seeking Question Answering”, investigates how people and language models approach questions. Rather than measuring only whether the final answer matches a reference, it considers the structure of an answering process.
The second recognised work, “Don’t Read Everything: A Curvature-Conditioned Query for Linear Attention”, examines a computational approach connected to how language models process information efficiently. The details are technical, but the central concern is important: how to use computational resources without losing the information needed for a task.
These are research achievements, not newly approved undergraduate modules. They illustrate areas where students may later participate in research if they meet the relevant prerequisites and selection requirements.
Why the answering process matters
A system can produce a correct-looking answer for the wrong reason. For example, it might guess a number that happens to match the reference without correctly interpreting the evidence. A method that examines the answering strategy can help researchers understand whether reasoning processes differ.
For a student, this is closely related to examination feedback. The final answer matters, but the steps taken to produce it can reveal stable understanding or a fragile shortcut.
Suppose two programs calculate the same output. One uses a tested algorithm with a clear justification; the other relies on a special case that breaks when the input changes. The result of one demonstration is insufficient to judge reliability.
The same principle applies when evaluating a chatbot. It should not be trusted solely because one sample response was persuasive.
Why computational efficiency matters
Modern AI systems can consume substantial computing power, electricity and memory. Methods that improve how models process context may lower cost or make applications more responsive, but any claimed efficiency improvement needs rigorous comparison.
A student should ask how the researchers measured the result, whether quality changed, what hardware was used and how performance behaved at different scales. A speed improvement on one benchmark is not universal proof of superior performance.
These questions connect computing to broader environmental and economic concerns. If an AI system requires more resources to achieve a small accuracy gain, organisations should consider whether the benefit justifies the cost.
28 October: a book about becoming an AI researcher
The NTU CCDS article from 28 October 2026 reports the publication of Becoming an AI Researcher: Practical Advice for Graduate Students by Associate Professor Stefano Albrecht, with Cambridge University Press.
The article explicitly says the book is not a technical AI textbook. Instead, it explores selecting research questions, conducting experiments, handling feedback, writing, academic integrity and professional development during a doctorate.
This is an important correction to a popular impression: research is not simply running an existing AI model and producing a colourful chart. A research contribution should address an important question, use a defensible method and explain what the results show and do not show.
Students considering postgraduate study should distinguish between learning existing knowledge and producing new knowledge. A PhD involves uncertain outcomes, sustained effort, peer review and the possibility that promising ideas fail.
A useful research habit for undergraduates
Before writing code, state the problem precisely. Who needs the solution, and why does the problem matter? What has already been tried? What evidence would show an improvement?
Then write down the baseline and evaluation method. If you propose a new chatbot for student support, compare it with an existing process using measures such as correctness, response time, accessibility and escalation safety. Do not change the evaluation halfway through simply to make the model look successful.
This habit helps undergraduate capstones and school science projects as well as doctoral research. It is the difference between looking impressive and producing interpretable evidence.
13 November: computing education workshop is still upcoming
The NTU workshop listing schedules the International Workshop on Computing Education in the AI Age for 13 November 2026, from 9am to 5pm at NTU’s Tan Chin Tuan Lecture Theatre.
At this guide’s editorial time of 11 November, the event has not yet occurred. This page does not attribute fabricated remarks or outcomes to its speakers. The listed agenda addresses how universities, polytechnics and other institutions should teach programming and software engineering as AI systems generate increasing amounts of code.
The programme includes keynote talks, panels and interactive showcases, with intended audiences covering educators, researchers, students and professional practitioners. Readers interested in attending should verify current registration, eligibility and any fees on the event page.
The workshop raises a problem that also concerns secondary-school families: how should learners demonstrate their own understanding when a tool can generate plausible answers quickly?
The difference between using AI and understanding computing
Using an AI tool can be helpful when the task is to identify possibilities, explain an error or compare approaches. However, a student who copies a generated program without understanding it may have difficulty repairing it or recognising an unsafe assumption.
A meaningful assessment can ask a student to explain why an algorithm works, test its boundary conditions and defend a design decision. The tool may accelerate part of the process, but the student must remain accountable for the result.
The goal should be neither to pretend AI does not exist nor to declare foundational learning obsolete. Students need to understand what automation can do and what reliable engineering still requires.
NTU CCDS Connect 2026: fundamentals over hype
A 9 June 2026 CCDS Connect article reported discussions among faculty, students and alumni about the enduring importance of computing fundamentals.
The central message is clear: as AI tools automate more routine coding, graduates need stronger architectural thinking, problem formulation, testing, design and understanding of the principles behind a system. They may also need to work across different professional fields.
This is relevant to applicants who assume that the best computing degree is the one promising the greatest amount of prompt engineering. A university education should provide the ability to evaluate the next generation of tools rather than depend on a particular product.
A student should still learn to program. But coding practice is a route to understanding abstractions and software behaviour, not the whole purpose of Computer Science.
Which NTU CCDS undergraduate degrees are available?
NTU’s College of Computing and Data Science programme list includes the following full-time options:
- Bachelor of Computing (Honours) in Computer Science.
- Bachelor of Computing (Honours) in Computer Engineering.
- Bachelor of Computing (Honours) in Data Science and Artificial Intelligence (DSAI).
- Bachelor of Computing (Honours) in Artificial Intelligence and Society.
- Defined double-degree combinations with Business or Economics and a route linking Accountancy and Data Science and Artificial Intelligence.
- Other interdisciplinary and joint degrees, plus a separate part-time Bachelor of Technology in Computing with its own admission criteria.
The list represents programme categories. Details can change between intakes, and some routes have additional requirements. A double degree is not automatically available to every applicant who selects a single degree.
Computer Science
Computer Science examines algorithms, software design, systems, data structures, networks and the logic of computation. Students can later apply those foundations in AI, security, software engineering, databases and other fields.
A student who enjoys problem solving at the level of algorithms and program architecture may find this direction suitable. But they should be prepared for mathematical and theoretical work as well as code.
Computer Engineering
Computer Engineering connects computing with hardware, digital systems, embedded devices and the interaction between software and physical equipment. A student may need to understand electronics, processors, sensors and communication as well as programming.
It can be a strong fit for someone who wants to build machines or digital systems where software must interact reliably with the physical world. It is not merely a different name for a general Computer Science degree.
Data Science and Artificial Intelligence
NTU describes its DSAI degree as a four-year direct-honours programme, jointly offered by CCDS and the School of Physical and Mathematical Sciences. It combines statistics, computing, machine learning, advanced analytics, projects and responsible AI.
A strong Mathematics background is especially relevant. A student who enjoys extracting meaning from complicated data and understands that prediction can fail may appreciate the blend of statistics and software.
The degree’s published career examples include data engineering, AI, analytics and related technical roles. Those are examples of possible pathways, not guaranteed job placements.
Artificial Intelligence and Society
NTU lists Artificial Intelligence and Society as an undergraduate computing degree. The title signals attention to the interaction between technical systems and society, but the official curriculum determines the exact subjects and mathematical demands.
Students should not assume it is a nontechnical humanities programme merely because it contains the word “Society”. Equally, a student interested in public policy or human behaviour should examine whether the degree’s balance of computing and social analysis fits their goals.
Part-time Bachelor of Technology in Computing
The college’s programme list includes a part-time computing route for eligible working adults. Its qualifications, age and work-experience rules differ from those of full-time undergraduate applicants.
An adult learner should inspect the exact programme description and whether the work-study structure is compatible with employment. The eduKate NTU BTech admissions guide owns the detailed route rather than repeating it in a news digest.
How to choose between NTU Computer Science and DSAI
A student who likes programming and general software design may value Computer Science’s broader computing foundations. Someone who enjoys statistics, probability and model building may prefer DSAI. A hardware-focused student could investigate Computer Engineering.
Do not make the choice by asking which degree has the higher salary in a single survey year. Read the compulsory mathematics and computing curriculum, internship arrangements and capstones. Compare the kinds of projects you want to build and the subject areas you enjoy enough to study intensively.
A student can also investigate how to specialise after admission. Some programmes permit electives, minors or second majors subject to requirements. However, programme flexibility does not mean every combination is possible.
A practical comparison exercise
Write down a problem you genuinely want to solve. For example, “How can buses arrive more reliably when demand changes?” A Computer Science approach may emphasise robust scheduling systems and algorithms. A DSAI approach may emphasise demand prediction, uncertainty and data pipelines. A Computer Engineering approach may involve connected sensors and on-board systems.
All three could be useful. The best choice depends on which part you want to understand deeply. A student should learn the overlap rather than assume the disciplines are in competition.
Then check whether the actual NTU curricula and faculty opportunities support that particular interest. The illustration does not imply that any one degree guarantees work with a transit operator.
NTU CCDS admissions for Academic Year 2027
NTU’s official admissions page lists separate application windows by qualification. For AY2027, the key listed periods are:
- Singapore-Cambridge GCE A-Level: from the 2027 A-Level results release until 19 March 2027.
- Local polytechnic diploma: 1 February to 21 February 2027.
- International Baccalaureate Diploma: 15 October 2026 to 19 March 2027.
- NUS High School Diploma: 1 December 2026 to 20 January 2027.
- Other international qualifications: dates vary, including routes beginning 15 October 2026, with their own deadlines.
The official portal may include additional document deadlines and qualification-specific conditions. Applicants must also check the minimum subject requirements for their chosen degree. A strong interest in AI is not an academic prerequisite waiver.
A-Level applicants: check the revised UAS and Mathematics requirements
NTU explains how its University Admission Score (UAS) is calculated for different A-Level examination cohorts. For applicants who sat A-Levels in 2025 or later, the new calculation uses three H2 content subjects and General Paper, with certain other subjects considered when they improve the score; Project Work has a separate pass requirement.
This should not be confused with the rules applied to older A-Level cohorts. The correct policy matters when someone compares past grades with current admissions.
Computing applicants should identify degree-specific Mathematics requirements and other subject conditions. A programme’s cutoff or indicative profile from an earlier exercise is not a guarantee for the next one. Applicants should follow NTU’s official admissions documents.
Polytechnic applicants: diploma relevance and mathematics
A local diploma graduate should check whether the degree accepts the diploma and what additional conditions apply. A project portfolio may help explain interest, but the university decides academic eligibility.
Some ICT diplomas provide extensive software experience but less advanced mathematics. A prospective DSAI student should assess readiness for probability, statistics, calculus and computational theory. Where gaps exist, early revision can improve the university transition.
If advanced standing or exemptions are available, the student should wait for formal assessment instead of assuming a shortened course duration.
IB and international applicants
Applicants should match their specific qualification to NTU’s correct route, which may involve tests, transcript requirements or different deadlines. Do not copy the A-Level closing date into an international-qualification application without verifying it.
Always submit through NTU’s official admissions process. The university says it does not engage third-party agents to enrol undergraduates. Any promise to secure an NTU place for a payment should be treated with caution.
Tuition and financial aid: what does NTU Computing cost?
NTU’s 2026 entering-cohort tuition table lists S$8,300 annually for eligible Singapore citizen entrants in most standard undergraduate programmes. Specific degree categories may have different fees, and students with other citizenship or subsidy statuses face different rates.
The exact cost for a CCDS student must be checked against the degree and entry cohort. Do not automatically apply the fee shown for Nanyang Business School or Medicine. A student entering in 2027 must confirm the future entering-cohort table rather than treat AY2026 as a binding quote.
A four-year illustration at S$8,300 annually would be S$33,200 in tuition if the correct cohort fee remained fixed through four normal years, before miscellaneous charges and living costs. This is not an individual offer or proof of all-inclusive expenses.
Budget for transport, food, devices, housing if relevant and any optional overseas activities. A university student may also incur costs from project materials or specialist equipment; programme guidance should be checked.
Scholarships and bursaries
NTU publishes different scholarships, grants, bursaries and loans. Eligibility can depend on citizenship, household need, academic performance, programme and other conditions.
An announced AI research award or college partnership is not the same as a scholarship for every undergraduate. Build a base budget using confirmed resources, then update it after a formal financial-aid offer.
Loans are financing and carry repayment terms; non-repayable support has different rules. The eduKate university aid guide owns the broader comparison.
What kind of learning makes a graduate useful in the AI era?
Consider three stages: understanding the problem, building a system, and evaluating its consequences. A student who skips the first may create elegant software nobody needs. A student who skips the second may understand a problem but not be able to implement a solution. A student who skips the third may release something unreliable or unsafe.
An undergraduate should therefore develop mathematical reasoning, programming, testing, data literacy and communication. Security and ethics should not be treated as optional moral decoration. They determine whether people can trust the result.
AI tools are useful for practice when they explain concepts, suggest edge cases or help compare designs. But a student should be able to reconstruct an important piece of reasoning independently and recognise when a response is wrong.
The most durable skill may be the habit of questioning an apparently successful answer.
Example: using AI to plan bus routes
Suppose a model suggests a new bus route that reduces travel time in simulation. Before deploying it, planners must ask whether the data represents school holidays and rainy days, whether accessibility needs are considered, and whether reducing average travel time makes a small group much worse off.
A model of demand could be inaccurate in new developments where historical data is sparse. The planning team may need new observations, consultation and an evaluation of trade-offs.
This shows how computing, geography, mathematics and social responsibility meet in a practical problem. It also explains why disagreement among AI researchers can be healthy: different methods reveal different aspects of uncertainty.
Career planning: not every student should pursue AI research
Some students enjoy theoretical AI and may later study a PhD. Others prefer software products, cybersecurity, systems engineering or data pipelines. Each direction is valuable when it solves real problems well.
A student interested in research should expect sustained reading, experiments, criticism and uncertainty. Someone interested in software engineering should expect requirements, design, collaboration and maintenance. A security specialist may need to investigate failures and explain risk to nontechnical teams.
Job titles and technologies change. A 2026 employer’s favourite framework may be less relevant in 2030. The university’s task is to develop people who can learn new tools and assess them. Students should take responsibility for project work and internships rather than assume a degree name alone produces employability.
What do the 2026 research awards tell employers?
An award can show that a research contribution was recognised by peers under particular criteria. It does not mean the approach is universally best for every application. Employers still need to test whether a method is appropriate for their operational constraints.
Similarly, a student who participates in a research project should be prepared to explain their actual contribution. Working in a prestigious lab is less informative than being able to discuss the hypothesis, method, evidence and failure modes.
Student life, research opportunities and campus culture
CCDS publishes student projects, research experiences, club initiatives and alumni stories through its news and events hub. These can help applicants discover a range of interests, from AI agents and visualisation to accessibility and sustainability.
Some opportunities are competitive or require technical prerequisites. A college profile of one exceptional student is not a promise that every freshman can enter the same research group. Students should investigate eligibility, time commitments and whether they prefer research, entrepreneurship or industry projects.
For families, practical matters include distance to NTU’s main campus, the weekly class schedule, transport, residential options and the availability of academic support. University life can be demanding, and consistent learning habits matter as much as high-profile competitions.
A good student community allows learners to collaborate, ask questions and recover from mistakes rather than hiding uncertainty.
Full Subject-Based Banding and the path to CCDS
Full Subject-Based Banding allows Singapore secondary students to take subjects at G1, G2 or G3 levels as appropriate. Those are secondary subject levels, not direct NTU degree admission categories.
A teenager may later pursue suitable A-Level, polytechnic, IB or other eligible routes. The exact university prerequisites and competitive admission process determine opportunities. A PSLE score does not automatically grant or rule out admission to Computer Science or DSAI many years later.
Mathematics is a particularly important foundation. Algebra, functions, probability and logical reasoning prepare students to understand how algorithms and models work. Science contributes experimental discipline; English helps with requirements, documentation and clear explanation.
A student can also learn basic programming as an exploration activity. But a coding-club certificate is not a substitute for formal qualification requirements. Build genuine understanding and use the official admissions information when course choices become consequential.
For the wider educational context, eduKate already has a JC H2 Computing 9569 guide and Full SBB secondary education guide.
Three useful decisions after reading the 2026 news
The A-Level student: compare Computer Science, DSAI, Computer Engineering and AI & Society by compulsory modules. Check subject requirements and mark the 2027 admission deadline.
The polytechnic graduate: understand diploma acceptance and the degree’s mathematics demands. Prepare truthful project evidence and the appropriate February 2027 application.
The parent worried that AI will replace programmers: look at architecture, problem formulation, testing and human judgement. These are the capabilities emphasised in the college’s 2026 discussions. Do not base a degree decision on a single prediction about the future of coding.
Frequently asked questions
Is NTU CCDS a government university college?
CCDS is part of Nanyang Technological University, a publicly funded autonomous university in Singapore. It houses undergraduate and graduate computing and data-science education.
Did Yann LeCun announce that language models are useless?
No. His 3 November talk argued for world models as a promising direction and criticised limits of existing methods. NTU researchers also published different perspectives on the importance of language and reinforcement learning.
What were the EMNLP 2026 Best Paper Awards for?
Two CCDS faculty were recognised for research into human-versus-LLM answering strategies and efficient attention computations in language models.
Does NTU offer Data Science and Artificial Intelligence?
Yes. The DSAI degree is described as a four-year direct-honours programme jointly offered by CCDS and the School of Physical and Mathematical Sciences.
Is Artificial Intelligence and Society a nontechnical degree?
The programme is listed as a Bachelor of Computing. Read the official curriculum and prerequisites; the title alone does not establish the balance of mathematics, computing and social topics.
When do NTU computing applications close for local polytechnic students?
NTU lists 21 February 2027 as the end of the local-polytechnic application window, which begins on 1 February 2027.
When is the computing-education workshop?
13 November 2026, according to NTU’s published event listing. As of 11 November, it is upcoming, not yet completed.
Does AI generation mean Computer Science is no longer useful?
No. The college’s public discussions emphasise the increasing importance of foundations, architecture, testing and judgement as tools evolve.
Can a Full SBB student eventually apply to CCDS?
Later admission depends on eligible post-secondary qualifications and programme rules, not on a secondary subject level alone.
Official sources and connected eduKate reading
- NTU CCDS official news and events hub
- NTU CCDS world-model debate, 6 November 2026
- NTU CCDS EMNLP 2026 Best Paper Awards
- NTU CCDS research guidance book, 28 October 2026
- NTU International Workshop Computing Education in the AI Age, 13 November
- NTU CCDS Connect discussion on computing fundamentals, June 2026
- NTU CCDS undergraduate programmes list
- NTU Data Science and Artificial Intelligence degree
- NTU undergraduate admissions 2027
- NTU 2026 incoming-cohort tuition table
- eduKate: NTU BTech Computing adult-entry requirements
- eduKate: university admission and qualifications guide
- eduKate: JC H2 Computing syllabus
Editorial note, 11 November 2026: The article distinguishes scientific debate from established facts, 2026 recognition from new degree requirements, and future event schedules from completed events. Fees relate to the stated entering cohort, and programme-specific 2027 admissions rules should always be checked live. Unverified keyword volumes and employment promises have not been invented.