The search engine outfit was showing off its chatbot in a promotional video and gave the wrong answer to a question. Investors who hoped the Bard would save Google's search engine from an AI-restored Bing rushed to sell their shares in the company wiping more than $100 billion off its value.
Alphabet stock slid by nine per cent during regular trading in the US.
In the response by the chatbot to: "What new discoveries from the James Webb space telescope (JWST) can I tell my nine-year-old about?"
Bard's response includes an answer suggesting the JWST was used to take the very first pictures of a planet outside the Earth's solar system or exoplanets.
The error was picked up by experts, including Grant Tremblay, an astrophysicist at the US Center for Astrophysics, who tweeted: "Not to be a ~well, actually~ jerk, and I'm sure Bard will be impressive, but for the record: JWST did not take 'the very first image of a planet outside our solar system'".
University of California Observatories professor Bruce Macintosh tweeted: "Speaking as someone who imaged an exoplanet 14 years before JWST was launched, it feels like you should find a better example?"
Google said the error underlined the need for testing new systems. Bard has been released to a team of specialist testers and has yet to be rolled out to the public.
"This highlights the importance of a rigorous testing process, something we're kicking off this week with our trusted tester programme," a Google spokesperson said.
"We'll combine external feedback with our internal testing to ensure Bard's responses meet a high bar for quality, safety and groundedness in real-world information."
Bard is based on a so-called large language AI model, a neural network that mimics the brain's underlying architecture in computer form. It is fed vast amounts of text from the internet in a process that teaches it how to generate responses to text-based prompts. However, this can also lead to the chatbot repeating errors from the information that it absorbs.
Since Microsoft announced its involvement with ChatGPT, Google has been in a panic to catch up, and this sort of mistake shows its weakness.
One analyst is that it is starting to look like Vole was going to be a formidable competitor now against Google's really bread-and-butter business -- who could have seen that coming?