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IBM allow free access to quantum processor online
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IBM has made a functioning quantum processor available to the public over the internet.
Quantum computing is widely seen as an evolution of computer technology, which may allow for much faster calculations than today’s machines.
The technology is still in its infancy, but one expert said it was a “small step” towards a useful quantum computer.
IBM said it hoped to see processors up to 20 times larger in the next decade.
Traditional computers process all their information using bits - information stored in tiny transistors that can either be on or off - interpreted as values of one and zero.

Quantum computing instead takes advantage of a mechanic called superpositioning that allows quantum bits - or “qubits” - to have values of one, zero, or both at the same time.
Researchers believe this core difference will eventually lead to powerful devices with processing power that will exceed the limits of classic computers.
IBM’s quantum processor is located in its TJ Watson Research Centre in New York. Quantum processors are notoriously sensitive, so it is being kept at supercooled temperatures in a cryogenic refrigerator.
It has just five qubits that can be manipulated, but the company expects processors of 50-100 qubits to emerge within the next decade. General-purpose machines, which IBM calls “universal” quantum computers, will eventually use more than 100,000 qubits.
IBM’s cloud solution allows users to drag and drop logic gates - a core principle of processors - on to the individual qubits to form algorithms or experiments. Those can then be sent to a simulator, or added to a queue for the real quantum processor to work on.

“IBM has made a small but very significant step towards a useful quantum computer,” said Chris Ford, Professor of Quantum Electronics at Cambridge University.
“This will only be useful for experts who know what they are doing, but the very idea that it’s available to all may bring quantum computing to the attention of the general public, and encourage more people to be interested in how physics makes this new form of computing possible.”
The potential power of quantum computing to perform advanced calculations is also a concern for the security industry, as it may make it possible to easily crack existing encryption methods.
Current security standards rely on the extreme complexity of encryption - something advanced quantum processing may be able to handle.
The US National Institute of Standards and Technology has announced it will hold a public competition for new encryption standards that will be more difficult to crack - hoping for a quantum-proof standard by 2023.

Mobile game Sea Hero Quest ‘helps dementia research
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Dementia researchers have developed a video game that could lead to the development of early diagnostic tests for the disease.
The way players navigate the 3D levels in Sea Hero Quest will be anonymously tracked and sent to the researchers.
Understanding how people navigate 3D environments is important because the skill is often one of the first lost by people who have dementia.
Researchers say the game could generate an unprecedented amount of data.
“We have never seen anything undertaken in dementia research at this scale before,” said Hilary Evans, chief executive at Alzheimer’s Research UK, one of the organisations involved.
“The largest spatial navigation study to date comprised fewer than 600 volunteers.
“Providing the research community with access to an open-source data set of this nature, at this scale, in such a short period of time is exactly the kind of innovation required to unloc k the next breakthrough in dementia research.”
“If we tile that information together, we can get a sense of how dementia changes over a lifetime, and other demographic factors.”
Dr Spiers stressed the game was not itself a test for dementia.
“If you’re worried about your memory or any changes to your health, speak to your GP,” he said.
The researchers plan to share the first results of their data collection in November.