Strange science takes time
Posted: Wednesday, January 09, 2008 8:30 PM by Alan Boyle
Scott Eklund / Seattle Post-Intelligencer file
University of Washington physicist John Cramer is preparing to perform
an experiment in reverse-time quantum causality with the use of lasers.
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The late astronomer Carl Sagan popularized the saying that "extraordinary claims require extraordinary evidence," in reference to reports of alien visitations. Generating low-cost commercial fusion power, isolating antimatter and tracing reverse-time causality aren't as far out there as UFOs, but a similar rule might well apply: Extraordinary science requires extraordinary effort.
With that in mind, here's a progress report on three extraordinary science projects that have popped up in the news:
Reverse-time causality
It's been more than a year since University of Washington physicist John Cramer proposed to test a spooky corollary of quantum theory: that it might be possible to receive a laser signal before you send it. The problem was that Cramer didn't really have enough research money to build the experiment, which required sending entangled photons through prisms, filters, optical fibers and other devices. What's more, Cramer worried that the apparatus he planned to use would be available only for a limited time.
Once the general public found out about Cramer's plight, the contributions started flowing in: Donors provided more than $40,000 - which allowed Cramer to move forward with the backward-time research. He was also able to find alternate lab space, which meant he didn't have to worry so much about running out of ... well, time.
Cramer's backward research took the No. 2 spot in our recent Weird Science Awards competition. So how have things turned out?
It's taken longer than he expected to set up all the equipment for the first phase of the experiment, but this week Cramer told me that he's finally setting up the avalanche photodiodes required for making the fine measurements of single photons that will be required. "They're sort of like little geiger counters, made of silicon," he explained.
Cramer expected to start making measurements this week, but it will take still more time and effort to track down the retrocausality effect, if it exists. Happily, money is no longer an immediate concern. "I'm fine for the moment, as far as financial support goes," Cramer said.
Trapping anti-atoms
During last summer's visit to the CERN particle physics center on the French-Swiss border, I looked in on the ALPHA experiment to trap stable atoms of antihydrogen - which would afford the first-ever opportunity to study the properties of antimatter in the lab.
The ALPHA team, led by University of Aarhus physicist Jeffrey Hangst, has been engaged in a friendly competition to achieve the feat, vying with another team of researchers headquartered just a few yards away at CERN's Antiproton Decelerator. "As usual, it's a race here - it's a race hour to hour," Hangst told me.
By all accounts, the race continues. Hangst e-mailed me this progress report just before Christmas:
"... The short answer is that we don't have any headlines for you. We made some nice progress this year, and our understanding improved greatly, but we did not yet succeed in trapping antihydrogen. We gave it a go at the end of the run. Although we see lots of evidence for positron-antiproton interaction in the magnetic trap, we have as yet no evidence that antihydrogen atoms can be caught.
"The good news is that we have much-improved techniques for manipulating antiprotons and keeping them in a very small radius cloud in order to maximize the chance of catching the produced antihydrogen. We also began commissioning our imaging detector for antiproton annihilations. This should really help us next year in diagnosing what is going on.
"I'll keep you up to date on our progress next year. We are looking forward to it."
Low-cost fusion power
Every time I write about the quest to develop a nuclear fusion reactor, I'm reminded that the $13 billion international ITER project in France is not the only game in town. Over the past year or so, there's been a lot of buzz on the Internet about under-the-radar research into what some believe could be a low-cost fusion technology. The technology, known as inertial electrostatic confinement or Polywell fusion, was championed by physicist Robert Bussard - who passed away in October after a long battle with cancer.
Bussard's mantle has been picked up by a small team led by Richard Nebel, who has taken a leave from Los Alamos National Laboratory to head up Bussard's EMC2 Fusion Development Corp. Backed by a Navy contract, Nebel's five-person team is trying to pick up the technology where Bussard left it.
"What's there is interesting, OK?" Nebel told me today. "And the bottom line of it is, what we've been charged to do is reproduce that. Find out if it's real. Find out if or if not all this stuff is what it seems to be."
EMC2 Fusion has built an upgraded model of Bussard's last experimental plasma containment device, which was known as WB-6. (The WB stands for Wiffle Ball, a whimsical reference to the structure of the device.) "We got first plasma yesterday," Nebel said - but he and his colleagues in Santa Fe, N.M., still have a long way to get the WB-7 experiment up to the power levels Bussard was working with.
"We're not out trying to make a big splash on any of this stuff at this point," Nebel said. But he said he's hoping to find out by this spring whether or not Bussard's concept is worth pursuing with a larger demonstration project.
The initial analysis showed that Bussard's data on energy yields were consistent with expectations, Nebel said.
"We don't know for sure whether all that's right," he said, "but it'd be horrible for Mother Nature to give you what you expect to see, and have it all be bogus."
Sure, there's a chance that all this - a low-cost route to fusion power, the ability to trap antimatter atoms, the potential for quantum causality to turn back the clock - will turn out to be bogus. But maybe that's what extraordinary science is all about. Stay tuned.
