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Comment Re:So why the right hand? (Score 3, Informative) 258

Luckily, the physicist has since discovered another clever experiment which the aliens can use to differentiate between what we call matter and antimatter. There's a certain type of particle that can transform into it's antiparticle and back again. But the catch is that one of the transformations will happen more often than the other. That means that even if the alien swaps matter for antimatter they will still be able to tell which is which by looking at which transformation dominates. (More details here)

"Now," the physicist admits "this all assumes that the aliens haven't swapped the direction of time on us as well! Buggers might just have effects preceding causes." (See CPT symmetry)

Comment Re:Geeks never throw away old tech stuff (Score 1) 71

They just can't part with the Tevatron . . . this recycling line is just an excuse to keep it around.

Assuming you would want to, it is non-trivial to just dispose of 4 miles of superconducting magnets.

Anyways, the part of the Tevatron that you are most likely to find reuse is the 4 miles of tunnel. The civil construction to dig a tunnel that big, complete with tunnel penetrations and service buildings is a significant portion of the cost of any project. You would be a fool to just fill in such a valuable commodity just because you don't have a use of it today.

And that's ignoring all the parts that are already being scrounged for use in the NoVA upgrades. So no, keeping it around is not merely a case of geek sentiment.

Comment Re:It has now been named.... (Score 2) 226

It shall henceforth be known as the pleaseExtendOurFunding-ion.

No it's far too late for something that petty, that day has already passed. The Tevatron collider run will not be extended:

"Unfortunately, the current budgetary climate is very challenging and additional funding has not been identified. Therefore, based in part of the P5 recommendation, operation of the Tevatron will end in FY 2011, as originally scheduled." - W. F. Brinkman; Directior, Office of Science, U.S. Department of Energy

Fiscal year 2011 ends September 30, 2011. There is not yet a decommissioning plan.

Comment Re:The question being... (Score 1) 195

Does it work on the mac app store?

Yes. Any iTunes gift certificate is shared between all of the stores, iBooks, iTunes and Mac App store. I redeemed a gift certificate on my iPad and the balance showed up automatically on the Mac App store on my computer. Of course, they are both signed into the same Apple ID.

Comment Re:WTF is Eighty dollars millimeters? (Score 1) 126


Is dollars millimeters a new unit?

MM obviously stands for MegaMillion, and with the $ the number is clearly in hexadecimal, so the value represented is 120 MegaMillions. With the current value of the MegaMillion jackpot in excess of 242 Million USD, NYC was therefore ripped off for over 29 Trillion USD.


Comment Re:antihydrogen (Score 1) 269

Ahh, I understand the confusion now. I was trying to convey the fact that the anti-hydrogen wasn't around as anti-hydrogen for very long in just a few words. I should have said something to the effect of 'collided with the container' to be more exact.

I had thought of this issue for a few seconds when typing the post, but decided that as the anti-hydrogen atom was a composite of a antiproton and a positron, you could very well destroy it without destroying the composite pieces merely by separating them, thus allowing me a bit of liberty to simplify my diction.

Comment Re:antihydrogen (Score 4, Informative) 269

I think the temporary capture of antiprotons and antielectrons has been achieved before

You are correct. For example the Fermilab Antiproton Source, which creates antiprotons and stores them, has been in operation since 1985 [1], while the Fermilab Recycler has held onto a continuous stash of antiprotons for over a month [2]. And these are by no means the very first machines to capture and store antimatter, I'd have to dig though the history a bit more to find an earlier example.

Production of Anti-hydrogen (antiproton orbited by a positron) seems to have been achieved in 1995 at CERN, with Fermilab confirming production in 1997 [3]. But those atoms were destroyed immediately after being created, this is the first time I've heard of anyone successfully storing anti-hydrogen for any long period of time. So yes, the headline is misleading, we've been capturing antimatter for quite some time, it's the fact that you are capturing the neutrally charged anti-hydrogen (antiproton -1, positron +1, total = 0) that's the real news.

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