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We have built a fourth dimension of space and are about to look inside

We only ever experience three spatial dimensions, but quantum laboratory experiments suggest a whole new side of reality – including strange particle phenomena


October 14, 2020

By Jon Cartwright

YOU run through an open field with the wind in your hair. Or you dive into the ocean and feel the cool water surrounding you. At such moments we feel free and liberated. Few of us stop to pause to ponder the truth – that we are trapped in an invisible prison.

Up-down, left-right, forwards-backwards: these are the three dimensions in which we eat and breathe, make friends and grow old. It could be worse in the prisons. On the other hand, we never knew anything else. Despite some imaginary claims to the contrary, no one has yet experienced a higher dimension.

But now we're building our own synthetic additional dimensions in some of the most modern laboratories in the world. The concept is so far removed from our experience that it is hard to imagine what they might look like. However, we have already seen the ghostly effects of four-dimensional space contact on our own and wired electrical circuits with an additional dimension. It's unlikely to stop there. Now we've got the hang of it, there's talk of creating five, six, or even more dimensions, and even suggestions that exotic species might lurk like new particles in the extra-dimensional wilderness.

This is a limit that we cannot explore directly. Instead, we are forced to look for the subtle imprints that additional dimensions make on the three dimensions that we limit ourselves to. Even so, we could be in the process of expanding the limits of reality in a way that approximates the limits of our descriptive powers.

Talking about additional dimensions could be a …