The science behind Harry's magic tricks
Monday July 16 2007
Harry Potter and the Deathly Hallows hits shelves on July 21. Will Harry die? Will Ron and Hermione finally get together? Is Snape as evil as he seems? Will Dumbledore return?
But, for me, there is only one question: can the magic of Potter ever be reconciled with the rational laws of science? Harry's magical world casts a fascinating light on some of the most interesting issues now engaging researchers.
Memory Eraser
When Harry and his chums shout “Obliviate!”, they are casting a spell that can wipe out memories.
Over the years, this memory charm has helped the Ministry of Magic to keep the wizarding world secret from the Muggles should they stumble across a stray dragon.
As reported recently, Karim Nader at McGill University in Canada and his team have shown how some drugs can dampen down traumatic memories.
Now it seems more specific memory erasers may one day be possible.
A study by Andre Fenton and colleagues at the State University of New York shows that erasing memories is scientific fact.
The team discovered a crucial part of the complex mechanism that maintains recollections in the brain and has shown that by inhibiting a single molecule they can wipe out long-term memories.
The molecule is “protein kinase M zeta”, which maintains long-term memories by strengthening selective points in the web of connections between brain cells.
It follows that by using drugs to boost the activity of the enzyme, memory can be improved.
Conversely, by inhibiting the enzyme in tests on rats, Dr Fenton and his fellow “obliviators” were able to erase a memory — such as a rat learning how to avoid an electric shock.
The team will use its findings to guide research on treatments for disorders resulting from abnormal memory processes, such as post-traumatic stress disorder, neuropathic pain, and epilepsy.
But Dr Fenton agrees that wizards may understand the mechanism better than we do.
“I still don't know how they achieve selective memory erasure. All we've managed is global erasure which is something like reformatting a hard disk.”
Invisibility
When it comes to vanishing spells and invisibility cloaks, there has been major progress.
Mathematicians have put forward four different theories in peer-reviewed journals to achieve invisibility.
This year, one team actually realised Rowling's vision by showing — at least by means of a computer — how an invisibility cloak would work at close quarters.
Research by Sir John Pendry at Imperial College London and colleagues in America has shown how a cloaking device could work by making light waves flow around an object — just as a river flows undisturbed around a smooth rock.
In principle, their invisibility cloak could be realised using “metamaterials”.
These are materials whose properties can be used to alter the way they interact with light waves by manipulating their structure at the atomic level.
Sir John, who is the Muggle answer to Prof Albus Dumbledore, believes it is possible to warp light so it passes around a cloak made of metamaterials producing neither reflection nor shadow.
However, Sir John adds: “It is one thing to have an overarching theory that says cloaks are possible, but another to manufacture and market one.”
Anti-Gravity
Researchers from the US space agency Nasa would sell their souls to obtain Harry's broomstick.
But there have been many false dawns in the search for antigravity, a quest which has been pursued with vigour for decades: an anti-gravity effect would be a global sensation, as well as making the inventor fantastically rich.
In 1992, a Russian, Evgeny Podkletnov, announced in the journal Physica C that he had partially shielded an area of space from gravity. His apparatus consisted of a cooled and magnetically suspended ring of superconducting ceramic material 145 millimetres in diameter and six millimetres thick.
Podkletnov applied an alternating electric current to coils surrounding the disc to make it rotate and found that this set-up reduced the weight of any object placed over it by up to 2pc.
He observed the antigravity effect with a wide range of materials, ranging from ceramics to wood.
The faster the rotations, the more gravity's tug weakened. Inspired by Podkletnov, several scientific institutions, including Sheffield University, a Canadian team, and Nasa, have examined the work. Martin Tajmar, head of space propulsion and advanced concepts at the Austrian Research Centres in Seibersdorf, said this week that, so far, they have not been replicated.
“Nevertheless, there is still room to look for gravitational effects around superconductors. My recent research is looking into generating a force-field using accelerated superconductors.”
He likened the force field to the “tractor beams” used in Star Trek.
Another uplifting insight could come from the giant Large Hadron Collider (LHC) atom smasher, which goes into operation next spring in Cern, Geneva. Dr Brian Cox, of Manchester University, one of the army of physicists who will work on the LHC, commented: “We don't have a complete theory of gravity. . .and it's just possible that the LHC will discover phenomena that could point us towards a deeper understanding.
“It's exciting, but I don't anticipate floating from Manchester to Cern any time soon.”
