IT IS possible that 2011 will go down in history as the year we solved one of the greatest mysteries in physics: the identity of the dark matter that makes up much of the cosmos.
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Our elaborate and painstaking efforts to detect this elusive stuff have paid off not with a definitive detection, but with confusing and even contradictory results. They may yet turn out to be flat-out wrong (see 鈥�Dark matter mysteries: a true game of shadows鈥�).
Something similar could be said of the Higgs boson. December鈥檚 much-ballyhooed results from the Large Hadron Collider at the CERN particle physics lab near Geneva, Switzerland, were of such low statistical certainty that no one should be surprised if the sought-after particle slips away again as more data is collected.
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This might seem unsatisfactory. After years of effort and millions of dollars, is 鈥渕aybe鈥� the best we can do? Perhaps it鈥檚 inevitable when investigating the quantum world, where reality is about probability rather than certainty. In this deepest realm of nature, it is hard to pin down the moment when something flips from 鈥渦nknown鈥� to 鈥渒nown鈥�. Eureka moments become a thing of the past.
鈥淚n the quantum world, where probability is the reality, perhaps 鈥榤aybe鈥� is the best we can do鈥�
Hold on. Rewind 400 years. Discovery for Galileo might seem simple from our perspective. Having assembled his telescope, he merely pointed it at the night sky and recorded what he saw. The moons of Jupiter, our own moon鈥檚 mountains, the countless stars of the Milky Way: each triggered a fundamental reassessment of the universe and humanity鈥檚 place in it. Galileo鈥檚 discoveries were as profound in their own time as finding the Higgs would be today.
But in reality, it wasn鈥檛 so clear-cut back then. All Galileo could say about his first look at Saturn was that he had observed it had 鈥渆ars鈥�. Only 45 years later did Christiaan Huygens see they were actually rings; it took a further 20 years for Giovanni Cassini to show that there were many of them. It wasn鈥檛 until 1859 that James Clerk Maxwell suggested they must be made up of innumerable particles of rock, and it was another 36 years before James Keeler confirmed this by observation. So who actually 鈥渄iscovered鈥� the rings of Saturn?
Discovery has often been a protracted and messy business. Perhaps counter-intuitively, that may be particularly true when we think we know what we鈥檙e looking for. The detection process is likely to be drawn out as we try, however misguidedly, to fit observational data to our preconceptions.
The pressures on today鈥檚 researchers make that muddied process of discovery more obvious. Accountability is one factor. CERN has a responsibility to let the public know what it has achieved with its money. Establishing priority is important, too. Galileo鈥檚 method 鈥� sending out cryptic messages that, once decoded, described his discoveries 鈥� is hardly viable for researchers today. But 鈥渟tatus updates鈥� allow the fiercely competitive teams seeking the Higgs boson and dark matter to plant their flags in case what they鈥檙e seeing ends up being confirmed as the real thing.
鈥淒iscovery by trial鈥� may become a more common feature of science. And eureka moments may get fewer and further apart. But we shouldn鈥檛 mourn their loss 鈥� unless we are prepared to wait, perhaps even for centuries, to find out what dark matter really is.
