IceCube is an example of how great science, and especially particle physics, now often works on generational time scales. It took 30 years to get from the idea of the IceCube to actually drill its neutrino sensors into a cubic mile of Antarctic ice to locate a high-energy neutrino source. During that time, key employees retired, died, or moved on to projects that provided more instant gratification. Whitehorn’s experience is the exception, not the rule – many scientists have devoted years, decades or even entire careers to seeking results that never came.
The discovery of the Higgs boson took even longer than extragalactic neutrinos: 36 years from the initial discussions about building the world’s largest and most energy-rich particle collider – Large Hadron Collider (LHC) – to the now famous announcement of the particle’s discovery in 2012.
For Peter Higgs, then 83 years old, the detection of his eponymous particle was a satisfying epilogue to his career. He shed a tear in the auditorium during the announcement – a full 48 years after he and others first proposed the Higgs field and its associated elementary particle back in 1964. For Clara Nellist, who was a PhD student and worked at the LHC’s ATLAS- experiment in 2012., it marked an exciting beginning in her life as a physicist.
Nellist and a friend showed up at midnight before the announcement with pillows, blankets and popcorn and camped outside the auditorium in hopes of getting a seat. “I made it to festivals,” she says. “So why would I not do it for possibly the biggest physics announcement of my career?” Her determination paid off. “To hear the words ‘I think we have it!’ and the jubilation in the room was just such an amazing experience. ”
The Higgs particle was the last piece in the puzzle, which is our best description of what the universe consists of on the smallest scales: the standard model of particle physics. But this description may not be the last word. It does not explain why neutrinos have mass, or why there is more matter than antibody in the universe. It does not include gravity. And there’s the little thing in that it has nothing to say about 95 percent of the universe: dark matter and dark energy.
“We’re at a really interesting time because when we started, we knew the LHC would either detect Higgs or rule it out completely,” Nellist says. “Now we have a lot of unanswered questions, and yet we do not have a direct roadmap that says that if we just follow these steps, we will find something.”
Ten years after Higgs’ discovery, how does she handle the possibility that the LHC may not be answering more of these basic questions? “I’m very pragmatic,” she says. “It’s a little frustrating, but as an experimental physicist I believe in the data, and so if we do an analysis and get a zero result, then we go ahead and look somewhere else – we just measure what nature provides.”
The LHC is not the only major scientific facility looking for answers to these existential questions. ADMX may be the garage band for LHC’s stadium rockers in terms of size, funding and staff, but it also happens to be one of the world’s best shots at uncovering the hypothetical axion particle – a leading candidate for dark matter. And unlike at the LHC, ADMX researchers have paved a clear path to finding what they’re looking for.