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Comment: Re:Leaders (Score 0) 52

If they don't know what they are doing, then why are they the leaders?

Because they have access to the biggest club. They claim Earth's resources as their own, and can back that claim with (outsourced) violence, so everyone else either obeys or starves. Actual competence in using those resources is irrelevant.

Besides, it's not like they're actually in charge - market logic or the "Invisible Hand" is. They have some leeway in interpreting its will, and particularly competent ones can sometimes even suggest a course of action, but ultimately they are just pampered slaves.

An executive's job is a purely ritualistic one: they're posing for the public while interpreting orders from high. The only real difference between them and, say, an Aztec high priest is that the Invisible Hand wants its victims starved rather than TempleofDoomed, which is less messy. Well, currently they victims are mostly just made destitute rather than outright killed, but born-again InvisibleHanders are working hard to change that.

Of course, the real problem with this scenario is that the Invisible Hand is not self-aware and can't think ahead, so the end result is that no one is in charge. Explains a lot, eh?

Comment: Re:Assertions not based on facts (Score 1) 400

by Copid (#49787057) Attached to: Creationists Manipulating Search Results

Potential DNA and fresh tissue is being found in dinosaur bones. From what we currently know about DNA and tissue, there is no way it should be able to survive millions of years. The simplest answer is that these bones are not millions of years old.

That's a really interesting discovery, and it has led to some work on what we know about how that stuff breaks down, but are you really sure that's the simplest answer? Given what we thought we knew about tissue, that material shouldn't have lasted thousands or even hundreds of years, so there's clearly something we don't understand at all going on. Simply moving the timeline doesn't do much for you--I don't think that soft dinosaur tissue comports with anybody's model of how old those bones are, so a more robust explanation that doesn't rely on our old assumptions about decay is necessary. It turns out that there are ways to preserve tissue for a lot longer than we thought, which is interesting, and that result makes a lot more sense than throwing out geology and radiometric dating.

2. Lucy (often deemed as one of the first missing links found) has recently been shown to possibly have at least one bone from a baboon.

"At least" is doing a lot of heavy lifting. That's one bone out of 89, which still leaves a lot of the skeleton unaccounted for. It's embarrassing for the researchers, but it's still an overall skeleton of something different. If the question is, "If one was a mistake, could everybody have made 88 more mistakes?" Sure, it's theoretically possible, but at some point you're just assuming that anthropologists can't do anything right.

The age of rock layers are generally determined by the fossils found in them, and the age of the fossils are generally determined by the age of the rock layers.

"Generally" is the key word here. It's not as though the whole process is bootstrapped that way. There are a lot of techniques that combine to create that textbook geological column. Index fossils are one piece of it, but there's also the fact that lower layers were laid down before higher layers and the use of radiometric dating to date layers independent of other references. If you can date a layer with an absolute method, you can be relatively certain that the layer below it is older than that absolute date, etc.

It's worth noting that the patterns in the geological column were noticed before the theory of evolution was ever suggested--there's very real stuff going on there that needs to be explained, and evolution over long periods of time explains it quite handily. Nothing else makes a lot of sense. I've heard claims of hydrological sorting and a worldwide flood, but the evidence against that is staggering. It just doesn't hold up.

Comment: Re:a microscopic black hole won't hurt you (Score 1) 123

by HiThere (#49787035) Attached to: Prospects and Limits For the LHC's Capabilities To Test String Theory

Are you sure? ISTM that it would initially prefer either electrons or protons, and when it had swallowed a couple of them it would repell any more. (Electrons are smaller, so it might prefer them, but they are also more uncertain as to their position, so it might prefer a proton.)

So say it swallowed an iron nucleus. This would give it a strong positive charge, so it would repell any additional nucleus. The question is could it also swallow electrons, or would they go into orbit around it?

*My* guess says that it would need to be sufficiently larger that gravitational effects would dominate over electromagnetic effects. OTOH, since 6 picometers is around 1000 times the size of an iron nucleus perhaps I'm overestimating the problem. That said, what's going to slow it down? This is an accelerator, so even if it created something with the mass of Mt. Everest, it wouldn't be at rest, and would, in fact, be moving far above escape velocity.

Comment: Re:View from a patent holder ... (Score 1) 76

by HiThere (#49785645) Attached to: Supreme Court Rules In Favor of Patent Troll

Given how bad many issued patents are, I feel that it's the presumption of validity that is the mistake. And that the baby being thrown out is a baby predator...which we would be vastly better off if it were killed.

There actually *is* a good case to be made for certain patents, but for such a small percentage that with the current system even eliminating all patents would be a net gain.

Comment: Re:Terraforming potential? (Score 1) 256

by Rei (#49785427) Attached to: How To Die On Mars

First off, you're misusing temperature. You don't call it heat if all of the particles are moving in the same direction and unionized, you just call it "wind". It only becomes heat if that windstream suddenly slams into a non-moving solid surface and becomes instantly thermalized (but of course even then that would be a very short-lived event as it would correspond with a pressure rise and the deflection of the stream behind the high-pressure zone). Additionally, nor would that be the windspeed touching the surface as, obviously, wind forms boundary layers.

Secondly, hundreds of km/s from Venus escape to Mars intercept? That doesn't at all correspond to any delta-V chart I've ever seen.

Comment: Re:Creationism (Score 1) 400

by HiThere (#49785413) Attached to: Creationists Manipulating Search Results

Sorry, but you fall afoul of the problem of "What constitutes reasonable proof?" This is a serious problem, as if we are Bayesian reasoners, then what consititues reasonable proof is highly sensitive to our priors. It is also provable that for certain sets of priors there is *NO* evidence that could possibly switch one from one set of beliefs to the other.

You outline what you are currently considering a set of proofs, but that means that you think they would suffice to convince anyone. This is not true. And "Creationist" is not a single set of priors, but rather several such sets, so even if an argument would suffice to convince one particular "Creationist" it might well fail on others. Now flip this around. Would you really change your opinions if they produced what they considered was good evidence? I truly doubt that. You are just certain that they can't produce what *YOU* consider good evidence. But be aware that you, also, cannot produce what they consider as good evidence.

What we call "reality" isn't what we sense, it's what we believe about what we sense. And that's all the reality we can ever know. And this is mathematically provable if you assume that we are Bayesian reasoners. (It's probably true anyway, but you can't prove it without the assumption.)

Comment: Every language has its gotchas (Score 2) 259

by Rei (#49784155) Attached to: How Much C++ Should You Know For an Entry-Level C++ Job?

And it's important for new programmers to learn them - more important than learning syntax.

  For C++ for example I'd warn about classes containing pointer member variables with implicitly-defined assignment operators / copy constructors. You have Foo a and Foo b, where Foobar has a member variable "int* bar". So the newbie does "a.bar = new int[100];" then later "b = a;" then later b goes out of scope, then they try to use a.bar and the program crashes. Seems to be a very common C++ newbie mistake. Eventually they learn to see pointers in class definitions as having big "DANGER" signs over them calling their attention, and/or rely on smart pointers.

Any others that people can think of that are common?

Oh, here's one more: iterator invalidation. A newbie who's not warned about this in advance will likely get bitten by it several times before the point gets driven into their head: "if you're using a class to manage memory for you, it's going to manage memory for you, including moving things around as needed."

Comment: Re:I am amazed (Score 2) 194

by Rei (#49783805) Attached to: A Text Message Can Crash An iPhone and Force It To Reboot

Yep, they have been UTF-16 for a long time. And Unicode has been widely broken for a long time. It's not a coincidence.

Someone on StackExchange did some tests last year, adding in 4-byte unicode characters in common applications and seeing how they behaved. The results were really bad:

Opera has problem with editing them (delete required 2 presses on backspace)
        Notepad can't deal with them correctly (delete required 2 presses on backspace)
        File names editing in Window dialogs in broken (delete required 2 presses on backspace)
        All QT3 applications can't deal with them - show two empty squares instead of one symbol.
        Python encodes such characters incorrectly when used directly u'X'!=unicode('X','utf-16') on some platforms when X in character outside of BMP.
        Python 2.5 unicodedata fails to get properties on such characters when python compiled with UTF-16 Unicode strings.
        StackOverflow seems to remove these characters from the text if edited directly in as Unicode characters (these characters are shown using HTML Unicode escapes).
        WinForms TextBox may generate invalid string when limited with MaxLength.

I've had more than my share of these sort of experiences too.

UTF-16 is dangerous, and should be phased out as much as possible. Where absolutely needed for performance reasons, it should be an internal representation only, hidden from the developer as much as possible. In particular, "length" functions should return the actual string length in characters, not code units; indexing functions should take character offsets; not code unit offsets; and returned "single characters" exposed to the developer should be of a format capable of handling multi-code-unit glyphs. Anything involving working with actual singular UTF-16 code units should only be available as a "for advanced users only, use at your own risk" functionality.

Comment: Re:Terraforming potential? (Score 1) 256

by Rei (#49783677) Attached to: How To Die On Mars

. So basically you'd need to impart almost 6x as much energy (36x as much speed) to get to Mars as to just escape Venus

Yes, the velocity would need to be tens of kilometers per second. But really, what's the limiting factor here? Certainly not skin drag, when you're talking something on the necessary scale here. Viscosity losses, radiating the energy away to space as heat? The energy can't effectively radiate away as heat, that's why the funnel is there, to reflect IR while transmitting visible light from the sun. There's not many options for the gas to lose energy except to accelerate.

Basically that "negligible drag" would be the only thing providing a supporting force to the funnel.

Negligible from a systems perspective. But from the perspective of the funnel, it's tremendous force. The mass of the funnel is insignificant compared to the mass of the rising gas when you're talking about a megastructure.

I wonder though what might happen if you directed the CO2 to Venus's L4 or L5 points? Could you build up sufficient mass to create a stable bubble of CO2

That would be.... unusual. What would you call that, a "Gas Dwarf"? I really have no clue how much you could have persist stably there, but I'd be really curious to know. It'd be particularly strange if you could make it out of a combination of gasses that are breathable - aka, limiting the CO2 levels, O2 from CO2, and any mix of Venusian/Jovian N2, Ar, and He as buffer gasses as needed. If the water vapor levels were low then there would be little in terms of cloud cover to reflect light. Earth's atmosphere absorbs about 1/3rd of the sun's energy, so with two passes through it'd absorb about half; at Venus's distance it'd probably be a pretty comfortable temperature. Gravity would be tiny. Obviously not long-term stable due to the solar wind, and high radiation, unless you artificially create a miniature magnetosphere. But in the short term...?

That would be so weird to be floating "midair" in a temperate breathable environment with no land anywhere.

Comment: Re:Hobbit (Score 1) 256

by Rei (#49783411) Attached to: How To Die On Mars

Well, certainly more realistic than living on the surface. And probably easier to set up than a Mars habitat - terrain is irrelevant and your entry is so much easier - plus, even normal Earth air is a lifting gas on Venus. And it'd be no less self-sustaining (that is, to say, "not very" ;) ).

There's no need to send people offworld to do science, whether to Venus or Mars. But while there's no need for any kind of "facility" at all, manned or otherwise, for robotic equipment on Mars, the concept of some sort of floating "facility" on Venus is pretty important. Any sort of craft designed to tolerate Venus's surface environment is going to make a terrible analysis lab or sample return vehicle. I mean, even solar panels would have to be heavily shielded on a sampling run to not be destroyed; there's very little that you can have exposed that can tolerate that environment. Sampling and analysis or return on Venus is best done in two stages: 1) Buoyant craft that repeatedly dive and rise the atmosphere like submarines and take samples on the surface, and 2) a floating platform containing any analysis equipment or return hardware, high gain communication with Earth, and solar panels to recharge the batteries of the sampling craft while samples are being offloaded.

Venus's surface is really unusual and it'd be neat to know more about what's there. I'm still not big on the concept that we need humans there to do it, but at least a floating platform of some kind would be important. The only advantages I could see for having humans would be to cut the communications latency with the samplers to allow for smarter sampling decisions without requiring them to wait in the harsh environment for round-trip communications on Earth, the ability to repair samplers, and perhaps mildly better local analysis of samples and/or decisions about what to bring back. Hard to justify the added price tag, though.

"Your attitude determines your attitude." -- Zig Ziglar, self-improvement doofus

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