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Comment Bad reporting, but.... (Score 1) 129

Actually, it is an interesting result. AFAICT, they have taken one of the ideas that came out of quantum optics (the JCM) and created an experimental system that apparently allowed for coupled JCM system to form a simple lattice (probably where they misappropriated the "crystal" metaphor from).

As for what this is good for? Seems like right now it's too simple, so basically nothing, But researchers anticipate this idea will find use as a quantum simulator for studying dissipation and/or decoherence from quantum systems that are far from the equilibrium state. The basic idea seems to be that in this highly coherent JCM lattice system, you can have tight control of tunneling and similar non-linear phenomena. It may make it easier to simulate quantum emergent behavior (quantum effects that show up in macroscopic phenomena).

Using this technique as a quantum simulator tool might be compared to using an analog computer to quickly simulate differential equations more efficiently than a digital computer. For those that like a car analogy, it might be compared to using a tricked out multi-barrel carburetor to study venturi/Bernoulli equations rather than retask your ignition timing / fuel injection computer to do this...

Comment Re:I can simply ignore all health and diet advice (Score 1) 291

Just about everything that is bad for you today is being negated a few years later. Can't find the link today, but at one point "research" showed that jeans were responsible for higher risk of cancer. So I will just continue to live my life and enjoy it to the fullest. If something kills me, at least I had a good time.

I think you might be alluding to the two theories about jeans and cancer.

One theory was that azo-dyes( commonly used in the pigments of cheap denim jean brands and leather products) might emit cancer causing aromatic amines. Basically this "research" led to a partial ban on the use of certain AZO-dyes and it's likely that we are safer as a result. You can now wear jeans w/o worrying about that problem at least.

The other theory was that wearing tight jeans (or other tight pants in general) seems to be correlated with a higher incidence of testicular cancer in males and yeast infections in women (potentially creating a greater risk for cancer). Apparently this theory was debunked, although tight pants are still responsible for reduced fertility (in both men and women)

Perhaps this reduced fertility will allow you to live your life and enjoy it to the fullest. ;^)

Comment Re:abstract is rather different (Score 3, Funny) 269

I was about to post something similar. The spin is quite strange given the reading of the abstract.

FWIW, I believe the original study that identified the 3 SNPs in educational attainment is here, but as mentioned it's a very weak statistical correlation as it only contributes to about 1 additional month of schooling on average. Also the assumption that the genes vary in terms of SNPs is also a big assumption which may be false too.

Basically, they seem to be mostly saying it's unlikely that a small mutation (because that's what a SNP is mostly) that was selected/amplified by evolution can determine our intelligence. That's really baby steps in this question.

Perhaps some sort of DNA methylation which is correlated with in-utero nutrition levels interacts with the underlying DNA expression somehow that is a better proxy for what we think of as intelligence (which is only weakly correlated with academic achievement). If so, we probably aren't going to find it by this technique at all. Kinda makes this total non-news in my book.

Comment Re:Stopping the spread of germs (Score 1) 174

It's not to clean your hands. It's to keep the doorknob germ free.

Sorry, that does not compute. What's the point of keeping the doorknob germ free, if everyone that needs to open the door has to touch a dirty rag and compromise their hand (that's swallowing the spider to catch the fly)...

Hand sanitizers mostly work against bacteria and not so much against virusses.

That' a common misconception. The latest generation of alcohol based hand sanitizers (when used correctly) work well as a virucidal agent. However, hand sanitizers often don't work well against certain spore forming bacteria and some common problematic bacteria like Clostridium difficile. The main problem with hand sanitizers is that people often don't use them correctly (e.g., they don't use enough and/or let it dry before rubbing their hands), and/or they tend to dry out your skin (dissuading people from using it as much as they should in some environments). Of course soap and water generally work better, but many people often don't wash their hands correctly either.

Comment Re:Stopping the spread of germs (Score 1) 174

1. Although alcohol based hand sanitizers work reasonably well against germs (mostly viruses and a few types of bacteria), they generally need 15-30 seconds to do their job well enough. You generally don't touch a door handle that long, nor is it likely to glop enough on to your hands to meet that threshold.

2. Alcohol based hand sanitizers are highly flammable, glopping a flammable substance all over a door handle will not make OSHA your friend.

3. At the end of the day, the washcloth is likely just wet w/o the needed concentration of sanitizer which basically renders them a germ infestation hotspot.

FWIW, a more mainstream technique is to use special metal alloy door handles. Although they only work on bacteria, they are at least a known proven method ;^)

In case you haven't noticed, nowadays, in large public gathering spots they don't even put doors on the restrooms at all. In other cases, I often simply take an extra paper towel** and open the door handle with the paper towel and toss the towel in the trash (most restrooms helpfully put a paper towel receptacle near the door just for this purpose). I'll try to make do with this method until they get the Star-trek sliding pocket doors installed everywhere...

** Having travelled in Asia, I've gotten in the habit of always bring tissue paper with me when out and about **just-in-case** it is not available even when not abroad...

Comment Re:What did Feynman think of later for E & M? (Score 1) 70

Don't know of such a writing, but perhaps he came up with a clever way to teach classical electrodynamics in a way that mirrors his electron-to-electron time-symmetric approach to QED (i.e., Wheeler/Feynman absorber theory). I mean in a way that is clever enough to think you might actually understand it w/o actually understanding it (which is sadly often a problem with Feynman lectures)... Path integrals and Feynman diagrams for classical electrodynamics? I shutter at the thought of that in sophomore-level physics...

Comment Re:Why the need to slow down the CPU ? (Score 1) 181

Can anyone please tell us why is there a need to slow down the CPU speed in order to put in more cores?

Thermals. More CPUs generate more heat, more heat with the same thermal envelope means you can't run each CPU as fast. Of course in a different environment (say with a liquid nitrogen cooling rig vs an air cooled rig), you could probably clock those CPUs higher.

Just because you can put in more CPUs doesn't mean you should. It used to be the limiting engineering factors were area vs chip yield. Now days thermals are arguably the most important consideration because often you are limited both thermally (and sometimes even electrically) to the amount of power you can deliver to a square millimeter of a computer chip.

Submission + - Death Valley's Sailing Stones Caught in the Act (livescience.com)

Capt.Albatross writes: The flat surface of the Racetrack Playa in Death Valley is littered with rocks, some weighing hundreds of kilograms, each at the end of a track indicating that it has somehow slid across the surface. The mechanism behind this has been the subject of much speculation but little evidence, until a trio of scientists caught them in action with cameras and GPS.

Comment Re:It'd hardly be surprising. (Score 1) 708

Motivation to preserve? There's really no good motivation for preserving DNA other than historical preservation. Think of this like preserving the source code for apple //e prodos. The ecosystem which that source code was valuable has been long lost, probably never to come again. Newer source code that serves a similar ecological niche in the new eco-system will evolve and probably be better than it ever was.

Some people seem to be obsessed with a philosophy no different than modern day Noah's ark where we somehow survive a major calamity and reboot the past. However, when confronted with modern day evidence of the problems with mono-culture and invasive species which threaten to unbalance whole ecosystems, they somehow fail to see that these survivors of this modern day Noah's ark are likely the vehicles of the new mono-culture and invasive species of our own making. Are we so important that our historical status-quo existence (e.g., the foods we enjoy from our childhood and furry animals we like to watch) trumps the natural development of the ecosystem, or should we learn to adapt or perish as nearly all other species under the sun?

I don't think we ask these types of questions enough. Certainly we have done quite a bit of homo-forming of our planet (e.g., dams, farming, agriculture, mining, industry) over the millennia to get where we are today, but should attempting to recapture the past really be a goal? Or are we just introspectively thrashing ourselves with self-hate for currently/temporarily being at the top of the food chain of our planet? With great power comes great responsibility, but on the other hand is this chant the new "white-man's burden"?

Comment Re:This is what they mean by "point of no return" (Score 1) 273

This stuff "just happens" over the course of literally millions of years(from your own links). Not a couple hundred.

I was not assigning fault or commenting on timescales or any coincidences, but pointing out this is likely spilled milk at this point.

Our species will need to adapt to survive, there is no going back to pre-industrial times (or even staying at 1990 carbon levels, as if that would have helped). These things eventually happen and we will need to deal with it eventually.

Note that a few methane plumes is not going to do anything on the timescales of my lifetime either (as many scientists have pointed out, this magnitude of methane plumes are likely to be eaten by bacteria before it gets into the atmosphere), but if large scale methane calthrate deposits (which these are not) were to actually to start a massive release at this point, there's not much we can do about it

Unless I'm mistaken, we really don't have much ability to control things on a geological level yet (and no blowing up all our thermonuclear arsenals to create nuclear winter does not qualify as control, it's basically an uncontrolled experiment). It may be premature to say that any efforts will likely be futile at this point because little is known about this phenomena in specific or climates in general, but it seems to me like we are at the mercy of our planet on this topic (as we always were)...

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