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Comment: Re:Dark Matter? (Score 1) 83

by JoshuaZ (#48681041) Attached to: New Paper Claims Neutrino Is Likely a Faster-Than-Light Particle
Possible, but there's no reason to particularly locate that hypothesis. In this conext, the specific particle which may be a tachyon is the electron neutrino. We already know that standard estimates of neutrino mass make it extremely unlikely that the standard three types of neutrinos are anywhere near enough mass to be more than about 5% of dark matter, and that's likely a vast overestimate. As to there being some other particles that are dark matter that happen to be tachyons- possible, but why even identify the hypothesis as relevant? The primary evidence for dark matter is gravitational: whether particles are tachyons or tardyons we expect their interaction with gravity to behave about the same.

Comment: Difficult to reconcile with SN 1987A (Score 4, Insightful) 83

by JoshuaZ (#48679995) Attached to: New Paper Claims Neutrino Is Likely a Faster-Than-Light Particle
The primary difficulty here is going to be the same data that was really tought to reconcile with in the OPERA experiment, namely the data from SN 1987A.

In that supernova (the first observed in 1987 hence the name), the supernova was close enough that we were actually able to detect the neutrinos from it. The neutrinos arrived about three hours before the light from the supernova. But that's not evidence for faster than light neutrinos, since one actually expects this to happen. In the standard way of viewing things, the neutrinos move very very close to the speed of light, but during a core-collapse supernova like SN 1987A, the neutrinos are produced in the core at the beginning of the process. They then flee the star without interacting with the matter, whereas the light produced in the core is slowed down by all the matter in the way, so the neutrinos get a few hours head start.

The problem for FTL neutrinos is that if the neutrions were even a tiny bit faster than the speed of light they should have arrived much much earlier. This is strong evidence against FTL neutrinos. In the paper in question, he mentions SN 1987A in the context of testing his hypothesis in an alternate way using a supernova and the exact distribution of the neutrinos from one but doesn't discuss anywhere I can see the more basic issue of the neutrinos arriving at close to the same time as the light.

Comment: "We didn't do it. Shutup or we'll do it again." (Score 2, Insightful) 153

by JoshuaZ (#48646997) Attached to: US Seeks China's Help Against North Korean Cyberattacks
North Korea's response seems to be "We didn't do it. Shutup or we'll do it again." See for example the quotes listed at http://www.cnn.com/2014/12/21/world/asia/north-korea-us-sony/index.html?hpt=hp_c2. After saying that they didn't do it, North Korea then says that:

The DPRK has already launched the toughest counteraction. Nothing is more serious miscalculation than guessing that just a single movie production company is the target of this counteraction. Our target is all the citadels of the U.S. imperialists who earned the bitterest grudge of all Koreans.

They then go on to say that their soldiers along with the hackers in question are sharpening their bayonets. North Korea seems to want to have it both ways: claiming that they didn't do it, but wanting everyone to take their threats seriously like they did. At this point, there really shouldn't be substantial doubt that North Korea is responsible. The only question is what the proper response is.

Comment: Re:Should Allah be translated to God? (Score 1) 880

by JoshuaZ (#48602341) Attached to: Apparent Islamic Terrorism Strikes Sydney
That's almost the exact opposite argument than you made in your post. You really don't seem to have a coherent point here. Apparently Christians who speak Arabic are perfectly ok using the same word. If they thought that the words had different meanings then they'd try to use different words in Arabic. The fact that they don't shows that your entire claim doesn't work. You seem to be confused about whether "Allah" is a proper noun or a generic. Like the word "God" in English it is both.

Comment: Re:Should Allah be translated to God? (Score 1) 880

by JoshuaZ (#48599671) Attached to: Apparent Islamic Terrorism Strikes Sydney
That's true in general for speaking in common contexts among Orthodox Jews. But even then, Orthodox people will simply sometimes say "God" in English or whatever the equivalent is in that language. And that's aside from the many less religious Jews who don't strongly have that taboo.

Comment: Re:Muslims? (Score 1) 880

by JoshuaZ (#48597683) Attached to: Apparent Islamic Terrorism Strikes Sydney
I don't know what "hate site" means in general, but that's at minimum a source that has very much already decided on their bottom line http://lesswrong.com/lw/js/the_bottom_line/, which means one shoudl already take it pretty skeptically. But that list isn't very helpful for a simple reason that it just shows that there are a lot of Islamic terrorist events which isn't terribly helpful: we already know that. The question being asked is how common are they compared to terrorist events motivated by other ideologies or religious traditions.

Comment: Re:Muslims? (Score 5, Informative) 880

by JoshuaZ (#48597571) Attached to: Apparent Islamic Terrorism Strikes Sydney
Getting data on these issues is complicated. If one restricts to the US, then about 10% of all terrorist attacks are Islamic. See http://www.washingtonsblog.com/2013/05/muslims-only-carried-out-2-5-percent-of-terrorist-attacks-on-u-s-soil-between-1970-and-2012.html. But not only is this restricted to the US, it uses a very broad notion of what counts as terrorism. If one weighs in the US by total deaths, then Islamic terrorism swamps everything else primarily due to 9/11. Worldwide, about 70% of all terrorist attacks are by Sunni Muslims but this varies from year to year. See for example the 2011 report NCTC report http://fas.org/irp/threat/nctc2011.pdf. Again, definitional issues can move this number up or down by a lot.

Comment: Neat interview (Score 4, Insightful) 122

by JoshuaZ (#48129087) Attached to: First Man To Walk In Space Reveals How Mission Nearly Ended In Disaster
The interview is neat, but this isn't anything being "revealed"- all these details were already known. You'll see them mentioned in many books discussing early space flight. They are I think mentioned for example in Buzz Aldrin's "Men from Earth".

Comment: Most disturbing bit (Score 2) 499

by JoshuaZ (#47877449) Attached to: Researcher Fired At NSF After Government Questions Her Role As 1980s Activist

In her 11 August response, Barr questioned whether the special agent who conducted the investigation “can be an impartial evaluator of academic scientists, or anyone with liberal political beliefs.” As evidence, she points to a posting on a blog maintained by the agent, a veteran who served in Iraq, and his family. The item is a copy of a popular Internet meme about an incident that supposedly took place in an introductory college biology course. According to the story, a “typical liberal college professor and avowed atheist” declares his intent to prove that there is no God by giving the creator 15 minutes to strike him from the podium. A few minutes before the deadline, a Marine “just released from active duty and newly registered” walks up to the professor and knocks him out with one punch. When the professor recovers and asks for an explanation, the Marine replies, “God was busy. He sent me.”

This makes it look really like this was a single agent who was unhappy with the left-wing views she had. At minimum, it is wildly inappropriate for a government agent in such a position to have that sort of thing on their blog (aside from it being just stupid). That goes together with the statement in the article:

Attorney Joseph Kaplan, of the Washington, D.C., firm Passman & Kaplan, says that, in his experience, the most common reasons for a finding of unsuitability are lying about one’s educational background, one’s employment history, or one’s criminal record. “If OPM determines that the person has misled or provided false information,” he says, “they can be declared unfit for federal service.”

Kaplan says he’s never heard of anyone being drummed out for political activity that occurred decades ago. At the same time, he says, the government’s decision is based not on anything Barr did during the 1980s but on how she explained those activities to federal investigators after coming to work at NSF.

Together this paints a potential picture of a specific agent going after someone they didn't like due to their political views and a bureaucracy going into overdrive to protect that decision. On the other hand, it isn't like she had no connections to the third organization- she knew two of the people who were convicted of the murder and by her own description kept up a correspondence with one of them while he was in prison. But keeping up correspondence with someone in prison is not evidence by itself of any problem, and there's really been no evidence presented that she lied or attempted to mislead in any way.

The article notes that this may be due to more general post-Snowded reactions which are making these sorts of things more common. In that case, this is exactly the wrong response.

Comment: Re:0.15 degree from a 3.7 kelvin... that's "cool" (Score 4, Informative) 39

This is extremely preliminary. It is likely that later work will be able to increase it further. And even an increase in a few degrees centigrade would have practical impacts. Moreover, the ability to make metamaterials of this sort may lead to superconductors with different ranges wherein they engage in magnetic quenching https://en.wikipedia.org/wiki/Superconducting_magnet#Magnet_quench which is important for safe and practical use of superconductors even today. It isn't uncommon for a bad quenching event to damage a particle accelerator. A particular bad example happened to the LHC back in 2008 dealing serious damage to the accelerator http://astroengine.com/2008/10/18/lhc-quench-ripped-magnets-from-concrete-floor/. Yes, this isn't immediately practical but it looks like there's a lot of potential.

Comment: Just don't tell De Beers (Score 4, Informative) 112

by JoshuaZ (#47319799) Attached to: Astronomers Discover Earth-Sized Diamond
Considering that the high price of diamonds is a combination of the De Beers monopoly together with their massive PR campaigns to a) make people use diamonds as formal symbols of affection and b) to make people unwilling to sell them second-hand once they've been owned, they should be worried. On the other hand, this is 900 light years away, so maybe they'll just lobby against any research into FTL travel.

Comment: Re:Legally speaking... (Score 4, Insightful) 205

by JoshuaZ (#47041687) Attached to: The NSA Is Recording Every Cell Phone Call In the Bahamas

Anyone at NSA who is participating in this is committing an act of war against a sovereign nation without any declaration of war.

Under what theory of international law? This behavior is clearly bad and is the sort of thing a country has a right to be pissed off about, but there's no coherent, conventional theory that makes this an act of war. The situation is bad enough without exaggerating.

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