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Comment Re:With the best tech that we know of (Score 1) 365

The definition of "advanced civilization" they used was Kardashev III, which uses total power on the order of 4.E37 watts. You're talking about a civilization that uses much less power. It still could be incredibly advanced compared to us, using energy incredibly efficiently (there's limits to the efficiency, so I'd suspect we're talking over Kardashev II here), or it could be operating on some principle we're not going to find for another million years.

As I said, it's silly to assume that any truly advanced civilization could/would consume or generate that much power. 4 × 10^37 watts is equivalent to 4.5 × 10^20 kg / s. That would mean they consume three Jupiter masses per year... the mass TOTALLY gone... poof. To give some perspective, the sun doesn't even do that. The sun doesn't even do 1 trillionth of that in its total output/year. It would take that civilization 1000 years to eat up an entire star (and they've been doing it for how long again?). Welp, let's just head to the next closest star and consume that. Wait a minute, it's gonna take 1000 years to get there? We need more power though!!!

Comment Re:With the best tech that we know of (Score 1) 365

However, one must agree that most radio communications are not point sources (not even "omni" antennas) and most high gain antennas are absolutely not so.

Consider our recent communications from earth to the New Horizons mission. These are "highly-collimated" (I'm putting that in square quotes because of course at the wavelengths being emitted it's not as collimated as a laser through an optical telescope would be) beams of radio waves leaving a 70m aperture (Tidbinbilla DSN) here on earth and going in one direction. Now I don't have time right now to dust off my college optics textbook to compute the diameter of that radio beam at the edge of the solar system, and at say 10 light years, or 100 light years away, but it will NOT be a compete sphere of radio waves and it will not be dropping off in intensity as the inverse-square of the distance.

I hope you can see this and I hope others can as well.

Like I said later in the post, a directed beam would have the best chance of getting to Earth; however, despite a high gain antenna's increased directional strength, the intensity still drops off in proportion to the inverse square. This is fundamental to the radiation field. In a perfect world, you can construct phase in such a way that intensity does not drop off, but this requires an infinite aperture with infinite power (see, for instance, airy beams).

So, yes, you can increase the range of communication, but you have to know who to shoot the beam at. This is why I suggested that we search for communications along the Earth-Sun ecliptic, since another civilization is more likely, perhaps, to have discovered us along that plane (which is still a long shot).

In theory, an advanced civilization with access to an extreme amount of energy (on the order of an entire star) could send out a sustained omni-directional signal strong enough to propagate throughout the galaxy. I find this to be far less likely, considering the already slim prospects for intelligent life.

Comment With the best tech that we know of (Score 2, Informative) 365

You couldn't detect radio signals from a planet. The electric field of a radio signal drops off inversely with the distance that it's traveled, the intensity inversely with the square of the distance. The closest large galaxy is about 2.4 million light-years away. Compare that to the measly 100 light-years that our radio signals have traveled. In Andromeda, the intensity of our radio signal will have dropped off by a factor of about a billion -- 2.4 million years from now-- compared to the already weak signals that we sent 100 years ago. So we will not likely find a signal from another civilization like our own.

As far as detecting extremely advanced civilizations goes, it's silly to assume that they will output enough infrared heat to be detected on a galactic scale. Assuming they're able to overcome their population constraints (lack of resources, planets, living in space far from another star, etc), the heat that they generate on their own would still be negligible compared to even the dimmest brown dwarf stars that we can detect... unless you think that their population exceeds the mass of many thousands of stars. It's not downright impossible for a civilization to have spread throughout a galaxy -- it only takes about 250 million years to orbit your own galaxy -- but it's rather unlikely that we could see them from such distance.

Furthermore, it took Earth about 4 billion years to form (mind you, just the planet... the evolution was much quicker with a bit of luck). As far as we can tell, the universe has only been churning out planets for 13.6 billion years. So you might be hard pressed to look at galaxies much farther than 9 billion light-years, since we can only receive light from civilizations that have had the time to develop on formed planets with good chemicals.

I suspect that our best bet is looking at exoplanets within our own galaxy. As of now, we don't have a sun-sized telescope, so we'll have to stick with examining planetary atmospheres via transits (so absorption spectra of light coming from the star through the atmosphere). With some extreme amount of luck, we may be able to see the byproducts of an organic life-form within a planetary atmosphere, but there's no reason that it'd be life with advanced intelligence.

If you wanted to search for a signal from another civilization similar to our own, they'd probably have to be directing a strong signal towards us intentionally (and from within our own galaxy). I suggested to Geoff Marcy during a colloquium that we should look for signals within our own ecliptic, since if we've been discovered as a non-advanced life-form (remember we've only been technologically 'advanced' for less than 100 years), they would most likely have discovered our atmosphere via the transiting technique. You can actually detect transits in mass simply by observing the intensity of thousands of stars over a few decades. No need to zero in on a planet with a *giant* telescope. He seemed to think it was a decent idea, but I probably would have been better off by emailing someone at seti :P

Comment legitimacy of the business (Score 2) 54

If your operations can be carried out in specific countries, you might be able to bypass some anti-hacking laws, or at least diminish some of the potential legal blame of 'going too far'. If you have to limit your offensive capabilities, there are probably ways of cataloging/surveying/classifying incoming attacks and thwarting them without doing anything illegal. The main factor in the success of this business relies on them providing monetarily valuable information to potential targets.

That said, what they say they're doing is not illegal, and it is probably already practiced by most security companies. It's just a business pitch. From TFA, they spend their time

monitoring underground chatter and markets, analyzing computer code meant to cause harm, watching the networks of potential attackers and poring over social media channels for signs of imminent attacks.

Comment SUBJECT LINE YEAAAAH! (Score 1) 73

Arts and crafts transcend science as a recognition of the fact that you can do whatever the fuck that tickles you during your short period of awareness of immanent existence.

Hobbies also give you:

- confidence (mad G-chord skillz!!1)

- a peaceful break from your current mindfuck

- a diversification of perspectives

- a sense of personal satisfaction security

- an extra way to relate to other people

- other stuff

Why wouldn't they help you in science?

Comment This is silly. (Score 1) 157

Machine learning won't 'solve' the economics problem (a problem which the TFA doesn't really define). The problem with math in economics is that economic time-series is extremely chaotic -- a practically infinitesimal change in initial conditions vastly changes the outcome of the system. Hey, remember how we can only predict the weather out 15 days *max* (using big ass supercomputers along with lots of soil moisture content, temperature, wind and other seasonal data)?... well the weather is just one of the tiny effects that propagate through economic time-series. Don't forget about psychology, trading strategies, oh yeah, and the fact that people are actively trying to trick your trading strategies into losing money.

No, machine learning is only natural to takeover a human's limited computational ability, but it doesn't solve the problem of unpredictability. In fact, it will make the market harder to predict for joe blow.

That said, TFA did rightly point out that economics is filled with lots of bullshit conjecture and over-rigorized high-brow nonsense.

Comment meh, keep OS X on your macbook (Score 1) 435

If you're interested in using windows, keep it on your desktop. In my experience, macbooks mesh a little better in research/workplace environments than windows laptops. For desktops on the other hand, where you might actually need some power (for gaming, design, personal computation, etc), windows is still king of compatibility.

Comment This is good. (Score 4, Interesting) 60

Improvements in battery technology are one of the most important stepping stones in getting us to that Star Trek utopia. Obviously they're used everywhere, but with 'perfect' battery technology, you don't need to worry about peak load energy production (ie, you can produce clean energy sporadically and save it if power demand isn't high enough), you don't need gasoline for cars, and your smartphones won't take hours to charge.

It seems that the main advantage of this breakthrough is, among other benefits, eliminating the heating problems associated with high energy devices like car batteries. One of the biggest problems people have with electric cars is that you can't charge them faster than you can fill up a tank of gas. FTFA:

The electrolyte in such batteries — typically a liquid organic solvent whose function is to transport charged particles from one of a battery’s two electrodes to the other during charging and discharging — has been responsible for the overheating and fires... The lithium itself is not flammable in the state it’s in in these batteries.

This is big, and I'm excited. Don't get me wrong, this isn't an overall solution to our dirty energy practices and clunky smartphones, but it's a big step in the right direction. Surely there will be design hurdles to overcome, which will probably delay implementation for some time, but this century is going to be great if we don't fuck it up too bad.

Also, if you can get past the paywall, here's a link to the nature materials article that the article didn't have:

Comment For the politically uninclined: (Score 1) 686

I don't spend a lot of time seeking out candidates that represent my views. In fact, it's really hard to find a candidate that represents even half of my views.

Here are some quizzes that I took that helped me solidify my political views. The first one ( was more extensive, and in my opinion, a bit better. It addressed net neutrality and gerrymandering, both of which I find very important:

Before I took this quiz, I was expecting to side with Hilary Clinton, but it turns out that I'm a bit more closely aligned with Bernie Sanders, partially because his platform is more clear on political values. While I support education, science, and thwarting environmental threats, I tend to agree with republicans on most other fiscal issues. The quiz gave me some republican candidates that I can tell my dad about (who is undeniably conservative).

Comment Free alternatives? (Score 0) 90

There don't seem to be very many good free alternatives other than microsoft's default package. I've wondered if it's possible for me to make my own security system, but I've never given it a good amount of thought.

If classification is the name of the game, couldn't you use some machine learning techniques based on what malware does and write your own classifier?

"Don't tell me I'm burning the candle at both ends -- tell me where to get more wax!!"