Browse Sections

• Education
• Special reports

Pitfalls of invisibility are clear to see

Miles Skinner
13/ 8/2008

MILES AROUND (13 Aug): AH, TO be a fly on the wall. Earwigging on endless ‘ever-so-important’ closed-door office meetings; sneaking into the sweet shop, bank vault or changing room...it will all soon be possible.

Want to tiptoe up to your nemesis and shout rude things at them as they’re about to start a very hot drink?

Then keep an eye on the University of California.

US boffins are moving ever-closer to developing materials that could render people invisible.

Researchers at Berkeley have already created a material that can bend light around 3D objects, making them ‘disappear’.

And they’re now saying the techniques could lead to every voyeur’s fantasy - an invisibility cloak.

"In order to have the ‘Harry Potter’ effect, you just need to find the right materials for the visible wavelengths," said Professor Ortwin Hess of the Advanced Technology Institute at the University of Surrey.

"And it’s absolutely thrilling to see we’re on the right track."

But a track that could lead where exactly?

It seems that the only reason you would want to be invisible is because you’re doing things you wouldn’t be allowed to otherwise.

Legitimate perhaps as a tool of war, or on the stage - but will Xiang Zhang (who is leading the studies) perhaps end up doing a Nobel?

Is it not conceivable he will realise that his pioneering has paved the way for perverts and pilferers to employ the product with far greater vigour and ease than he had intended?

How can you defend yourself against what ‘isn’t there’?

If anyone can find the technology, it’s those who shouldn’t...they’re always at the cutting edge (or rather just behind, waiting for the edge to cut off something they can steal and use for their gain).

Far more likely to be obtained by a clever criminal than by a millionaire philanthropist who wishes to remain anonymous scattering alms amongst the poor.

It’s fascinating, and a little more physically immediate than policing porn on the internet.

There’s not much point in existence without pushing the boundaries of science and progressing our knowledge along with infinity.

But if a little knowledge is a dangerous thing, a lot is more so.

And like the victims of dynamite, the broken eggs of the onwards omelette will always wish they could have seen it coming.

The science:

• The materials don’t occur naturally but were created on a nano scale, measured in billionths of a metre.
• The light-bending effect relies on reversing refraction - similarly to a straw appearing bent when placed in water.
• Previous efforts have shown this negative refraction effect using microwaves - a wavelength far longer than humans can see.
• The new materials instead work at wavelengths around those used in the telecommunications industry - much nearer to the visible part of the spectrum.
• Two different teams led by Zhang made objects made of so-called metamaterials - artificial structures with features smaller than the wavelength of light that give the materials their unusual properties.
• One approach used nanometre-scale stacks of silver and magnesium fluoride in a ‘fishnet’ structure, while another made use of nanowires made of silver.
• Light is neither absorbed nor reflected by the objects, passing ‘like water flowing around a rock,’. As a result, only the light from behind the objects can be seen.
• The fine structure of the material gives it light-bending abilities
• They could be used to make better microscopes, allowing images of far smaller objects than conventional microscopes can see

Pet hate of the week ...

FOOTBALLERS - or at least a disproportionate number of them.

When they’re not bonking geriatric prostitutes, swimming in their money pool or enjoying a good roast, they’re blackmailing each other over ‘sexual images’.

One can’t help wondering what will be the next depth to which one of our ‘proud lads’ descends.

What it won’t be, despite the salaries and constant claims of bringing it home, is ‘Talented team in World Cup triumph’.

The views in this column are those of the writer and not necessarily those of the editor, or the Stockport Express.