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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 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 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.

Comment: Re:Why it matters (Score 1) 293

Ah, so it would look like a hypothetical thing that we've never seen. Well that helps.

Yes it does- we have models of what that should look like.

Why should we expect that wormhole entrances are common?

If the apparent black holes in galactic centers are really wormholes then by the Copernican principle there exits should be about as evenly distributed as their entrances- we shouldn't expect some part of the universe to have a large number of exists.

Comment: Re:Why it matters (Score 1) 293

Why? Is there one nearby that we can observe with our extremely primitive and limited technology? Would we know it if we saw it?

Yes, we would know if we saw it. Essentially it would look very close to a white hole And we should expect that if wormhole entrances are common then by the Copernican principle we should see some exits near us. This is one of the major reasons to doubt this sort of thing. As to your question about other universes- GR is not really happy with wormholes going from universes to universes- no one has been able to get the math to work out in a reasonable fashion- there's a line between speculation that's decent science and complete science fiction, and right now wormholes fall into the first but wormholes that go to other universes fall strongly into the second. That could change in the future but right now that doesn't look at all remotely likely.

Comment: Re:Why it matters (Score 1) 293

The main way we've detect Sag A* is its massive radiation profile. That's a completely distinct issue from the issue of mass. But even the mass thing is a problem saying maybe it is filled with some sort of pseudo-matter is even more speculative than speculating it might be wormhole. And even if that is the case, the gamma and x-rays would still fry anything that got near.

Comment: Re:It is God. (Score 4, Informative) 293

I'm pretty sure that the anonymous coward was referencing Star Trek V where it turns out to be very much not God despite a certain fanatic's belief. This is where the famous line "What does God need with a starship?" comes from

Comment: Why it matters (Score 4, Interesting) 293

Given the intense environment around Sag A*, even if it turns out to be a wormhole it will be utterly non-traversable. However, there are hypotheses that wormholes to be stabilized require using negative matter At least, that's the most plausible mechanism suggested- so this would be inadvertent evidence that negative matter exists, which would be a really big deal. There's also speculation that a cosmic string could do something similar- note that a cosmic string is topological defect in space time these are not the strings from string theory although many forms of string theory would predict that such objects would exist. And of course, if wormholes exist in nature there's some small chance we can either make our own o find much smaller ones and put them to use. Unfortunately, there's a lot of dust and other debris between where we are and Sag A*, so even GRAVITY may have trouble getting enough resolution to figure this out.

Comment: Scott Aaronson's take (Score 3, Funny) 199

by JoshuaZ (#46662619) Attached to: P vs. NP Problem Linked To the Quantum Nature of the Universe
Scott Aaaronson is a highly respected quantum computing expert at MIT. His initial reaction at comment# 89 at is that "The abstract of that thing looked so nonsensical that I didn’t make it through to the actual paper. If anyone has and wants to explain it here, that’s fine." Given that I wouldn't take this too seriously.

Comment: Submarines? (Score 4, Insightful) 150

by JoshuaZ (#46659807) Attached to: Will Living On Mars Drive Us Crazy?
Aside from the number of people being smaller, this does't seem that different from a tour of duty on a nuclear submarine. Three months is normal for that. Having little time to shower is a minor stress which could easily apply to almost any military duty, and submarines are again in that category. Moreover, submarine showers are disgusting. At least with a Mars mission you won't have the constant movement and shaking. And they don't get the regular email contact because they are underwater. discusses some of the many unpleasant things about subs. It seems like the people who are worried about the "human factors" are massively overestimating what conditions human minds can actually cope with, and it seems they also aren't doing a good job looking at counterexamples to their worries. This shouldn't be that surprising though: Robert Zubrin in his excellent book "Case for Mars" argued that a large part of the medical and psychological research to see if humans could handle a trip to Mars was more excuses for grant funding than serious concerns.

Comment: Re:Hmmmm ... (Score 1) 75

by JoshuaZ (#46588057) Attached to: Physicists Produce Antineutrino Map of the World
Fukushima won't show up more than any other nuclear reactor, if anything since there's no longer an active reactor, it will produce fewer neutrinos. A nuclear meltdown does not in general involve the production of more radiation than a running reactor, the primary problem is that all the radioactive waste can get exposed.

Comment: The primary point not in abstratct but not summary (Score 5, Informative) 17

by JoshuaZ (#46429111) Attached to: HTTPS More Vulnerable To Traffic Analysis Attacks Than Suspected
The most interesting bit is not in the summary. Given individual websites they could identify which specific webpage one was visiting thus leaking with high probability all sorts of medical, financial and legal information. Examples used include from medicine the websites of the Mayo Clinic and Planned Parenthood, from finance Wells Fargo and Bank of America, and from entertainment Youtube and Netflix. This sort of thing could be used for all sorts of surveillance or blackmail. Even just knowing what Youtube videos one is watching could be used for such ends.

Comment: The key here is "Conference Proceedings" (Score 4, Informative) 62

by JoshuaZ (#46330325) Attached to: Publishers Withdraw More Than 120 Fake Papers
In many fields conference proceedings have little to no oversight. These papers don't get noticed at all or cited and for most purposes don't exist. The only real issue I can see here is that a large fraction of these are apparently coming from China and this is consistent with prior reports of serious problems with academic quality coming from China. It is possible that people are using these essentially fake papers to boost their publication counts which may give them some advantages as long as no one looks closely, but any institution that is a serious institution will look at everything one has published. I actually found this point more interesting:

Labbé emphasizes that the nonsense computer science papers all appeared in subscription offerings. In his view, there is little evidence that open-access publishers — which charge fees to publish manuscripts — necessarily have less stringent peer review than subscription publishers.

Considering how many complaints there are about low-quality open-access journals, this suggests that that isn't nearly as much of an issue as some people are claiming.

Comment: Re:Gravity wells and other distance issues (Score 1) 330

by JoshuaZ (#46320055) Attached to: Japanese Firm Proposes Microwave-Linked Solar Plant On the Moon
That's a good point, so from a strict get-there-once attitude this won't be so bad. However, I don't think that slamming into the moon is going to be a good strategy here unless they used some sort of extremely robust system which would create its own problems.

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