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Comment Re:further reason for a popular vote (Score 1) 642

While it's true that many Republicans favor changing the voting system one way and Democrats the other way, it is more than a little dishonest to imply that that means that each system is equally political, the demon of false-equivalency rears its head again. Indeed, you say that the Democratic plan is "an even more blatant attempt to rig the system" but I don't really understand how you can define a National Popular Vote as "rigging the system", especially in comparison to the alternatives.

If you look at the sorts of scenarios that each system allows, you can see that a National Popular Vote is inherently impossible skew and manipulate (ignoring voter fraud, which all systems are equally vulnerable to). There is simply no "worst-case" scenario for a NPV, the candidate with the most votes wins. There are cases where the result is different than it would be under the historical system, but no cases that are obviously un-representative. Take the current system, where a plurality in most states gets that candidate the entire block of votes. You could conceivable have a candidate win in a landslide despite getting dramatically less than a majority nationally. Under the district by district system, which will probably typically be more representative, you still have many cases, like Pennsylvania, where a state with a strong majority scrapes up a minimum level of electoral votes, that worst-case is even more drastic, with a Presidential candidate potentially winning by even more of a landslide with even fewer votes.

National Popular Vote has even more benefits as well, letting us concentrate on the nation instead of a privileged few. As one example, a few hundred thousand people in Miami will no longer drive foreign policy with an entire nation.

Comment Re:Why are you even on Slashdot? (Score 1) 589

No current or near future laser will do anything to the warhead itself. The warhead is designed to survive high speed reentry, good luck to make a laser that can exceed that energy release.

You are assuming that the parent is talking about ICBMs, which are the only missiles which have to survive any sort of reentry. Any shorter range land/air/water to land missile would have no reentry shield whatsoever. That's not to say that such shielding couldn't be installed, but it may very well be worthwhile to force your opponent to replace (completely arbitrary) 10% of their explosive payload with a heat shield.

Additionally, your impression of ICBMs is incorrect, in three big ways:

First of all, they do not have to survive high speed reentry, but low speed reentry, as they are not re-entering from an orbit, but from sub-orbital flight. Depending on the trajectory the reentry speed of an ICBM will vary from 4 to 7 km/s. We'll say 7, for the longest ranged missiles. The Apollo spacecraft are actual high-speed reentry craft, coming in at 11 km/s. While the maximum temperature a craft will sustain on reentry is linear with reentry speed, the total heat is based on the square, so Apollo entry speeds need to absorb nearly two and half times the heat.

Secondly, the materials which are used to create such heat shields are ablative, which means that the protective power of the shield is used up on reentry. While there is obvious difficulty in getting through the safety factor of an ablative heat shield it's still at depleted strength.

Lastly, in most modern ICBMs, the reentry stage is nowhere near the payload at close approaches. Instead the reentry stage deploys a whole host of goodies, chaff, decoys, multiple payloads, targeting aids, etc. At this point you are back to installing special heat shields on your payload, at the expense of yield.

Note that I don't mean to imply that an end-of-flight intercept is preferable or even similar to a launch intercept from a technical standpoint. The missile is going much slower shortly after launch, and the energy input required to ignite the fuel is much less than other kill scenarios. However, you exaggerate the difficulties of an end-of-flight intercept. Also, while an end-of-flight intercept is technically harder, it has the practical benefit of not requiring line of sight to the launch site at the launch time. If we ignore the requirements for being in the correct position to intercept the missile, then the simplest technical solution is to cut the fuel lines.

Comment Re:I'm pretty sure it doesn't work (Score 1) 419

None of those reference the fact that in this case the "secret" technology is one that their main competitor already has. In that case the response to conceal your own program is "Wow, this actually works." If you instead respond with "Pssh, this doesn't work. Like, at all. Man, you'd have to be preeeettyyy dumb to try to build a spaceship with this engine, which we haven't, because we're smart." then your operational security may be hampered a bit.

Comment Re:I'm pretty sure it doesn't work (Score 1) 419

Phantom Works just said they're not working with Shawyer. They didn't say the drive doesn't work. Given their nature, if the drive did work, they wouldn't disclose that because it would have profound advantages for classified work (e.g. KH-11/KH-12/etc. spy satellite maneuvering).

No, they would disclose that the device worked regardless of classified work, because China already has the drive and the designer of the drive. The only reason to lie about something like this working is to dissuade other powers from trying it themselves. When China gets it first, and knows that it works, and then America says it doesn't work, the Chinese know the Americans have something to hide. What's more, then all of China's military and civilian satellite have super awesome propulsion, and American civilian satellites get crummy propulsion.

So if Boeing says it doesn't work, either they got a broken engine, or it just doesn't work. (And given that this engine is theoretically impossible I'm betting on "It doesn't work".)

Comment Re:Good Advice (Score 1) 316

American insurance typically involves the patient paying part of the fee, usually 10-40 dollars depending on the service. It is to discourage us from going to the doctor when there's nothing wrong with us.

Yep. What foreigners don't realize is that taking time out of your day to go hang out in a waiting room and then sit uncomfortably and be poked and prodded is one of our favorite American activities. Videogames? Football? Baseball? Concerts? Sex? None compare to the joy of a visit to the Doctor. If our healthcare system didn't force us to pay admission for the pleasure I don't think any of us would ever do anything else.

Comment Re:what about nuclear fusion? (Score 1) 686

In this Astrophysicists professional opinion it is unlikely (and probably impossible) to construct a rigid "shell" structure which is able to hold itself over the sun, or even hold itself apart from it's own gravity field before collapsing into rubble (as another poster stated). If you did construct such a structure it would also be unstable and prone to falling into the sun, ala Ringworld, but if you could construct such a structure in the first place that may not be an issue.

The simple fact is that the stiffness/density ratio to withstand the gravity of a sun is enormous, probably impossibly so. Also, that sort of structure would probably have an enormous mass.

A very popular way of solving this is the "Dyson Swarm", which other posters have mentioned. Just keep building and launching normal satellites until they literally block the sun. An alternative (one which is not mutually exclusive to the swarm approach) is to build a structure that does not need to withstand gravity. Instead of a shell build a thin membrane that surrounds the sun, light enough that the solar radiation pressure that object feels is slightly larger than the gravitational pressure. Instead of tending to fall into the sun the entire balloon would inflate out from the sun until it was taut. The structure would then only have to withstand the tensile force of the excess solar radiation pressure, so lets say 1% of the gravitational force, and tensile force can be withstood with lighter materials than compressive force to boot.

So what would the areal density of such a membrane have to be?:

Pressure * MembraneArea = MembraneMass * Gravity

MembraneMass/MembraneArea = ArealDensity = Pressure / Gravity

Gravity = SunMass * GravitationalConstant / radius^2

Pressure = FluxDensity / c (assuming that our membrane is perfectly absorptive, also note that we don't need to take into account the pressure of the photons leaving the membrane, as they will be split evenly between the inner and outer surfaces and cancel each other out.)

FluxDensity = SolarLuminosity / MembraneArea (//*The SolarLuminosity is the total power output of the sun.)

MembraneArea = 4 * pi * radius^2

so: ArealDensity = (TotalPowerOutputOfSun / (4 * pi * radius^2) / c) / (SunMass * GravitationalConstant / radius^2)

The radius cancels out! That means that the same membrane (barring heat constraints) can be used anywhere in the solar system!

ArealDensity = (TotalPowerOutputOfSun) / (4 * pi * SunMass * GravitationalConstant * c)

ArealDensity = (3.839E26 Watts (kg*m^2/s^3)) / (4 * pi * 1.9891E30 kg * 6.673E-11 m^3/kg/s^2 * 3E8 m/s)

ArealDensity = 7.67E-4 kg/m^2

So all we need to do is make a very thin structural membrane, line it with incredibly efficient solar cells, as well as efficient transmission to the laser stations studded every few tens of thousands of square kilometers, into a sheet of membrane that masses around 7 grams a square meter! (safety factor, as well as extra to hold up those laser installations) Easy peasy, that's just an order of magnitude less than a sheet of ordinary paper! For an even more relevant example this paper references a current deployed solar array areal density of 80 g per square meter. Coincedentally enough that's actually exactly the areal density of a sheet of paper, so an order of magnitude of improvement is actually what we are trying to achieve.

As far as the total mass of this system, that's ArealDensity * 4 * pi * radius^2. Let's think really grand and build it 10% past Saturn. .0007 * 4 * pi * (1.1 * 1.43E9)^2 = 2.18E16 kg. That's only 3.6E-9 the mass of our planet, or 2.3E-5 the mass of Ceres, so once we get Asteroid mining started up that'll be no problem. Heck, if you wanted to be lame and build it at 1.1 times Earth's maximum distance from the sun you could make it more than 100 times lighter than the Saturn variant.

Comment Re:They often react violently (Score 1) 771

There are only 2 ways to win an argument:

You bring your opponent over to your point of view and they agree with your superior logic and evidence.

You are brought over to your opponents position and agree with their superior logic and evidence.

Unless I am mistaken, you haven't listed two way to win an argument; you've listed one way to win and one way to lose. These don't even exhaust the ways there are to end an argument.

There actually are two ways to win an argument, namely (1)You bring your opponent over to your point of view and they agree with your superior logic and evidence. (2) You bring your opponent over to your point of view through some logically irrelevant means.

The number of irrelevant means are endless: wear him down, make him feel stupid, encourage him to jump on the bandwagon ... the list goes on.

GP is correct, those are the only two ways to win the argument. You do list several ways to end an argument, but, for example, neither of you "wins" if you simply wear him down such that he doesn't agree with you but just wants you to shut up.

If during the course of the argument you decide that your "opponent" was right then you have both won. You now have more knowledge and/or wisdom than you had before, which is the closest thing to a win such a discussion can ever have. Your "opponent" wins as well, as his position has been vindicated, and he may have learned something or gotten more food for thought along the way.

It is terrible to view the "opponent" being correct as a loss. Humans hate to lose, if someone feels like their "opponent" being right will lead to them losing then the solution is simple: buckle down and find a way to convince yourself the other party is wrong. There are many ways to lose an argument, but being wrong and not realizing it at the end is close to the worst. The worst is being wrong and convincing the other party that you are right. A naive or overly competitive person will view this as winning, in truth that is a terrible loss for each of you.

Comment Re:not life as we know it (Score 1) 50

That would be an interesting next step to take. When I took my first CS class I put my own spin on the Game of Life, it was still an orthogonal board, but with two species, Cows and Wolves, with different propagation rules. You could make some interesting gliders with them, the Wolves appeared to chase the Cows.

Comment Re:Mindgames (Score 1) 54

According to the human players, poker is largely about mind games.

Really? The pros I have heard have spoken about probabilities, trying to determine your opponents' strategies (are they betting conservatively? do they bet on weaker hands more frequently than expected?), and measuring expected returns quickly. Tells and psychology seem to be a small part of their strategy, and unsurprisingly, professional poker players defeat the AI players despite the fact that computers have no psychology to play against.

"Trying to determine your opponents' strategies" is a portion of that mind game. The fact that professional human beings continually smoke current AIs is an strong indicator that psychological ploys are at work. If the game was all about probabilities then the computers would destroy human beings every time. As you say, the computers have no psychology to play against, they are generally predictable, and do not have the algorithms to judge character, intent, motivation (aka the psychological mind games) that would let them in turn predict the human's actions.

The sort of strategy you mentioned, determining whether a player is more likely to bluff with a weak hand, is exactly the sort of thing that will get an AI to lose their money once the human changes their strategy partially through the game, whether for a big hand, or over time just to throw off the other players.

Comment Re:In other words, (Score 1) 368

Al Awlaki was killed in Yemen, after the Yemeni government ordered him captured dead or alive, right? You need a better example than this for bashing the US.

Ah ok, so once you are convicted in Yemen the US military can be used to carry out the sentencing? Interesting, I didn't realize that this country worked for Yemen. Honestly though, I'm relieved. I used to think that the US was responsible for all of their actions around the world, and it made me pretty ashamed. Now I can just say "Sorry guys, we know this looks bad, but our hands are tied, Yemen told us to do this."

Comment Re:Bet I can guess some of the top ten (Score 1) 95

Who wants to bet that the top of the list of "flagged" sites will be comprised of EU government and law enforcement sites? I guess we'll only know for sure if they refuse to release a list of the top sites flagged. In fact, I dare say that the list will be so cluttered with joke flaggings that it will be difficult to determine what, if any, sites identified are actually "inciting terrorism" (not helped by the fact that one man's terrorist is another man's political leader).

You are incorrect in thinking that those are false positives. Every single flag is guaranteed to find a terrorist, the site being flagged, or the person doing the flagging. Obviously if you are going to sabotage their intelligence gathering with protests against Big Brother you must be one of Them.

Comment Re:Thinking back to Millenium Challenge '02 (Score 1) 547

A few boats might take damage or even be sunk, but I'd hardly think that the whole fleet would be in collectively in jeopardy.

The concern isn't that the entire fleet would be destroyed. As you have conceded, a few of our ships "might take damage or even be sunk". That's a pretty tremendous victory for Iran if that happens. Best case scenario they get a Ticonderoga class Cruiser, which costs about a billion dollars (although we haven't been building them for 27 years, so I'm not sure how we'd actually replace it). We may lose an Arleigh Burke instead, which Wikipedia places at $1.8 billion. If Iran can accomplish that with a couple million dollars in boats and rockets than that's an amazing upset.

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