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			by Alan Boyle 
			October 16, 2009 
			from
			
			CosmicLog Website 
			  
			 
			A worker is dwarfed 
			by components of the Large Hadron Collider's ATLAS detectorduring construction in an underground chamber beneath the 
			French-Swiss border.
 
 
			Is the future trying to save us from 
			ourselves?  
			  
			A series of scientific papers that have 
			been kicking around for a couple of years suggest that if the Large 
			Hadron Collider ever were to find something that shattered the 
			cosmos, the future universe might protect itself by sending a 
			backward-causality wave to break the LHC, or at least warn us.
 Sure enough, the LHC is broken - leading The New York Times' 
			Dennis Overbye to wonder half-jokingly whether there was 
			something to the claim after all.
 
				
					
					
					Does that sound spooky? 
					
					
					What if I told you that the idea 
					of going back in time to derail out a world-ending particle 
					collider goes back even farther, to a novel written about 
					the fate of the long-canceled Superconducting Super Collider?
					
					
					And that the author of that book 
					is a physicist who has been conducting research into... 
					backward causality? 
			To quote the actor Keanu Reeves, who has 
			appeared in a couple of time-travel sagas himself: "Whooooa!" And 
			just in time for Halloween!
 Each piece of the puzzle is relatively mundane by itself, but when 
			you put them all together, it could serve as the makings for a 
			science-fiction story as way-out as anything you'd see in "Bill and 
			Ted's Excellent Adventure," "FlashForward" or University of 
			Washington physicist John Cramer's book, "Einstein's 
			Bridge":
 
			  
				
					
					
					The papers on the LHC's 
					potential effects were written by Holger Nielsen of 
					Copenhagen's Niels Bohr Institute and Masao Ninomiya 
					of Japan's Yukawa Institute for Theoretical Physics. 
					   
					They suggest that the LHC could 
					produce exotic particles (such as the long-sought Higgs 
					boson), and that producing those particles would somehow be 
					so catastrophic that the event would send back a 
					timeline-altering signal to avoid producing them in the 
					first place. They even suggest that physicists create a card 
					game that would determine whether the LHC is allowed to 
					operate at the highest levels.    
					The game would be designed with 
					a minuscule chance of "losing," but if the physicists 
					actually lose the game, the LHC would be limited to 
					lower-energy collisions.
 
					
					Nielsen and Ninomiya's papers 
					were published on the
					arXiv preprint 
					Web site, which is a clearinghouse for all sorts of 
					papers (including suggestions that the LHC 
					
					could create a time machine or lead to 
					a relativistic hyperdrive).    
					Just because a paper shows up on 
					arXiv doesn't mean it's so. The big reason why the papers 
					are getting a second look is because a helium leak and 
					electrical breakdown forced the LHC to go dark just days 
					after it started up.    
					That's an example of 
					old-fashioned forward causality. Nevertheless, the shutdown, 
					plus the fact that the LHC won't reach full power for more 
					than a year, has led some folks to grumble that the project 
					is jinxed.
 
					
					This isn't the first time a big 
					particle-smasher has seemed jinxed. Back in 1990, the 
					Superconducting Super Collider looked like the next big 
					thing in physics - in fact, it would have been more powerful 
					than the LHC. But Congress moved to cancel the project in 
					1993, due to cost concerns.    
					Or was that the real reason?
 
					
					In Cramer's book, "Einstein's 
					Bridge," the Superconducting Super Collider ends 
					up getting built - but it opens the door to problems coming 
					in from a metaverse in a bad cosmic neighborhood. That 
					sparks a desperate effort to hold those problems at bay, and 
					change the collider's timeline if possible.    
					Without going into the details, 
					I'll just note that a similar plot twist finds its way into 
					another novel about the Superconducting Super Collider 
					titled "The 
					God Particle."
 
					
					Cramer is a particle physicist 
					as well as a novelist and columnist, and one of his latest 
					projects is to determine whether backward causality on a 
					small scale is actually possible under the rules of quantum 
					physics.    
					At last report, he was still 
					having trouble setting up the correct apparatus. But even if 
					the experiment is a failure, he can still make use of the 
					concept.    
					As he told me a couple of years 
					ago,  
			So what's the bottom line here?
 
			  
			Almost nobody thinks the LHC poses a 
			threat worth changing the past over. A lawsuit to stop the collider 
			is still being considered on appeal, however, and as we get closer 
			to the scheduled restart in mid-November, there may be a fresh surge 
			of particle-physics paranoia.  
			  
			If that's the case, don't be surprised - 
			and for heaven's sake, don't panic.
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