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Comment forget decoherence - think accuracy! (Score 1) 86

So they improved the decoherence by a factor of 10. This is nice, but no reason to abandon your RSA keys just yet. The real problem with quantum computing is not decoherence (i.e. the losing of superpositions due to uncontrolled entanglement with the environment) - its quantitative imperfections.

A quantum computer is basically an analog device. As you cannot observe states, there also is no way to "refresh" slightly inaccurate states, as a normal digital computer does. A NOT has to be exactly 180 degrees and not 179 or 181. No problem in toy or laboratory setups, where you only do a handful of gates and keeping your system isolated is the (currently) much bigger problem. 1% error might seem quite good in this setting.

But for any meaningful computation, you will require many millions of gates and your experimental accuracy will have to keep pace with that - in addition to keeping your system from decohering (which - at least in theory - can be mitigated by quantum error correction). Rotation angles would have to be not 1% but 0.0000001% accurate.

The problem is too remote to get much consideration now, but I'm sure that it will prove to be the final (and probably insurmountable) roadblock for any real-world use of quantum computers.


Comment abuse? (Score 1) 143

What kind of abuse does this new method detect? Talkum substitute? Scrubbing powder? Disinfectant? Or rather its intended, designated illegal-but-certainly-non-abusive employment as the psychoactive, addictive drug it happens to be.

You can abuse a screwdriver to kill somebody; using a gun for the same purpose is still illegal in most circumstances, but it would not be "gun abuse".


Comment Re:I wish there was an easy way to understand it (Score 1) 129

All in all, two thousands years ago, in Greece, people were arguing if the world rests on the backs of three elephants or three whales, and assumed that the world is flat.

The Greeks knew that the world was a sphere and also came up with a fairly good estimate of its circumference. Check out

also, there are no elephants in Greece ... ;-)


Comment Re:1D compression, AKA "Serialization" (Score 1) 129

Really just guessing here, but it might have something to do that you can only put so much stuff into a given volume before it begins to collapse and thus forms inner bounderies (i.e. black holes) and that this property is not additive. The reasoning would be:

For information you need states.
States have an associated energy.
The more states you use, the higher the energy density will be.
Energy density equals mass density.
Amassing enough volume units with a given density will eventually lead to collapse.
The larger the volume, the lower the (mass-, thus energy-, thus information-) density has to be to prevent collapse.

So the information capacity is sublinear in volume thus I = O(V^e) with the exponent e smaller than 1. The holographic principle states that e=2/3. This again is not implausible from a naive point of view, given that volume increases with the third power of the radius while gravity decreases with the inverse square.


Comment Re:Not really true AI we should be worried about. (Score 1) 583

Sure machines have taken our jobs in the past, and people have been able to find new jobs, but that trend cannot continue for ever. Eventually the only jobs available will be those that require actual creative thinking and ingenuity.

There will always be jobs which require loyalty to whoever happens to be on top of the foodchain as pretty much the only qualification. No power structure functions without them. Look no further than at the top floors of whatever company you happen to work for. And those kind of jobs seem to proliferate quite nicely despite ongoing automation in the lower ranks.


Comment Re:It's a bit of a problem really! (Score 1) 283

> How embarrassing.

Well, in German and all other languages which use the long scale, your calculation would have been correct. ;-) Here in Austria, a Billion is 10^12 and a Trillion is 10^18.

Otherwise, I totally agree. Also, the practice of routing most of the funding through the Pentagon is limiting the scope and usefulness of the research for non-military purposes.


Comment Re:There's another treatment that stops most T2 (Score 1) 253

I would need to solve the food texture

Well, the process of "fixing food texture" is probably mankinds oldest cultural achievement: its called cooking. Take some cookery courses - not some diet-crap, but serious gourmet-cooking. If it does not taste good, it cannot be healty.

I do not get any sort of "buzz" after excercise, I do not feel good about it, it just makes me cranky.

I guess this is quite normal - especially endurance training. If diabetes T2 is an issue, than high intensity strenght training
is probably the most effective way (in terms of time and will-power employed). The idea ist to completly exhaust every major muscle group for 60 to 120 seconds, therby inducing your body to build up new muscle mass over the next view days. The new grown muscle cells - besides increasing your base calorie consumption - should show normal (i.e. not yet degenerated) insuline sensitivity.

Half an hour twice a week is quite enough and the results are readily verifiable - in terms of the increasing weights you need acheive exhaustion. The drawback is that to do it effectively, you need training machines which allow you to isolate the respective muscle groups and set the respective training weight, so you cannot do it at home.


Comment Obligatory Douglas Adams Quote (Score 3, Insightful) 561

> I know a lot of high IQ people and they all have one thing in common. Being lazy. Smartest guy I know wastes most of every day playing Xbox and smoking pot.

âoeFor instance, on the planet Earth, man had always assumed that he was more intelligent than dolphins because he had achieved so muchâ"the wheel, New York, wars and so onâ"whilst all the dolphins had ever done was muck about in the water having a good time. But conversely, the dolphins had always believed that they were far more intelligent than manâ"for precisely the same reasons.â

â Douglas Adams, The Hitchhiker's Guide to the Galaxy

Comment Re:11000 miles? (Score 1) 330

> I've seen estimates of 1.2 mw per square km

from the cited article:

A single solar plant has the potential to generate minimum of 1250GW and maximum of 2000GW per square meter

Both figures are complete BS. Solar constant is about 1.36 kW/m^2 at 1 AU from the sun. Realistic over all electric peak powers might be in the 200 W/m^2 ballpark. This can only be harvested in orbit, however. On a planetary (or lunar) surface under a day-night cycle you get up to 1/4 of that, up to 1/2 for a sparse installation with sun-tracking.


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