Quantum computing is heralded as humanity’s next great technological leap forward — one on a par with the agricultural or industrial revolutions. But what is it, how does it work… and what on Earth is a qubit?

The UK has opened its first quantum computing hub, the National Quantum Computing Centre (NQCC). But what is quantum computing, how is it different to ‘normal’ computing, and what might it be used for in the future?

There are currently only six operational quantum computers in Britain, but that doesn’t mean that quantum computing is a fringe industry. In fact, according some estimates, the market for quantum computing will reach £55 billion by 2035 and, for the financial, chemical, life science, and transport sectors alone, those computers will be worth some £1.5 trillion in economic impacts.

At the £140million NQCC, built at Harwell in Oxfordshire, UK, and operated by the Science and Technology Facilities Council (STFC), work is underway to construct 12 operational quantum computers. Eight will be built by private business and four by government scientists.

The hope is that quantum computing will represent the next big technological revolution and it will be used to tackle some of humanity’s most pressing existential problems.

The tagline of this page is “Big (and little science) at STFC” The “big” might include the study of insanely immense cosmic structures, such as stars, galaxies and black holes — stuff so large that they literally bend the fabric of the Universe to their will.

The “little” might include the brain-blending world of the unimaginably small — the quantum world of the atomic and subatomic, where our macroscopic view of reality is rendered impotent and the illogical reigns supreme.

But, beneath all of this there lurks another level of reality where our ability to quantify reality breaks down and being ‘small’ takes on a whole new meaning…

The first direct detection of gravitational waves back in September 2015 was hailed as the discovery of the century, with the potential to revolutionise the way we study the Universe. But what are gravitational waves, where did they come from and why should we care?

What is gravity?
​To understand gravitational waves, you need to understand gravity.

In 1915 Albert Einstein published his General Theory of Relativity in which he showed that space and time are inextricably linked and form the fabric on which the Universe is built. This fabric is called space-time.

One way of thinking about space-time is to imagine it as a two-dimensional sheet — in reality, there four dimensions of space-time (three of space and one of time), but a sheet is much easier to visualise.
Einstein showed that gravity is an effect of the warping of space-time — any object with mass distorts space-time in its vicinity — effectively making a dent into which an object with less mass will ‘fall’. It is this acceleration of an object in a gravitational field that we think of as gravity.

Matter tells space-time how to bend and space-time tells matter how to move. Imagine a bowling ball making a dent in our imaginary sheet — if you roll a marble close to the bowling ball, it will fall towards it and accelerate — it might look like the marble is attracted to the bowling ball, but really it is just following the only path that the sheet will allow it to.

Explore the mystery of dark matter with our print-out-and-keep infographic guides (you don’t have to print it out, you can just look at it on your computer screen.. or phone… or tablet… the possibilities are endless!

Science is littered with concepts that seem custom-made to strain the limits of intuitive logic and high up on this list of scientific oddities is dark matter — a mysterious substance that accounts for about 85 per cent of all the matter in the Universe, yet is invisible and can only be detected by its gravitational effect on the matter we can see… but what is it?

To the ‘rational’ mind it might seem that dark matter is, at best dropped, the product of the fevered mind of a low-rent science-fiction writer, or, at worst, is something dreamt up by scientists to fill an embarrassing hole in their understanding of the Universe.

Dark matter’s existence was first suggested 80 years ago to explain anomalies in the behaviour of galaxies but is now accepted to be an essential component in the machinery of the cosmos. Without the gravitational input of dark matter, the Universe as we know it couldn’t exist. But, despite overwhelming evidence for its existence, science still doesn’t know what dark matter is made of.
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The trouble with dark matter is that, although it interacts with the gravitational force, it is immune to charms of the electromagnetic force, which is why we can’t detect it directly. Since we are made of ‘normal’ matter, we interact with the world through the electromagnetic force — tables feel solid because the electrons in the atoms in our fingers are electromagnetically repelled by the electrons in the table’s atoms; and we can see objects because our eyes collect the visible electromagnetic radiation (light) they emit or reflect.