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Comment Re: Fake News (Score 1) 270

1. That was just an old theory, and not a widely accepted one.

2. Given what we've just seen, it demonstrably isn't.

That doesn't mean that there aren't compounds formed at great pressure that can remain stable at moderate pressures and represent very dense energy sources - there surely are. Metastability is a very real thing. But apparently not in the case of metallic hydrogen at ~STP.

Assuming that this actually even was metallic hydrogen; even that is somewhat in dispute.

Comment Re:Maybe (Score 1) 204

Indeed, on both counts. And in particular I like the word "rogue planet". Again you have an adjective imparting additional information about another object ("Rogue X"), "rogue" can be readily quantified ("Not in a stable orbit around any particular star or cluster of stars"), and it's a very evocative term. And rogue planets are absolutely expected according to our current models. They'll be incredibly difficult to find, but they're out there.

We're also coming to the realization that there's a lot of objects, potentially including large ones, that are only tenuously bound to our solar system. And it's likely that we readily exchange this mass with other nearby stars over cosmologic timescales; parts of our solar system (primarily distant ones) likely formed by other stars, and things that condensed during the formation of our star system are likely now orbiting other stars.

Comment Re: Why is Amazon/Alexa even saving recordings? (Score 1) 114

Not quite true. The hardware detects a simple sequence of phonemes that might be Alexa. It then wakes up some software to try to parse the word. The data might still be shipped off to the cloud service for spurious wakeups. Names like Siri and Alexa are intentionally designed to have sequences of phonemes that don't appear commonly in English to minimise this.

Comment Re: Why is Amazon/Alexa even saving recordings? (Score 2) 114

I don't particularly worry about Amazon intentionally violating privacy with Alexa, but when you have something like that it's a wonderful target. The mute button is entirely software, so there are all sorts of things that an attacker can do if they compromise either an individual machine or the Amazon software update server. For example, it would be a trivial patch to make it stream the audio to a different cloud service when you press the mute button. Those thousands of people working at Amazon on Alexa also make it relatively easy to sneak someone into the company to exfiltrate user data. Even if their software is entirely bug-free, what happens when someone manages to do a dump of everything that Alexa has learned about a few million users?

Comment Re:R&D (Score 1) 103

Apple does a lot of Research that isn't directly product-oriented, too; a quick look at their patent portfolio will show that.

Sorry, no. It may not be tied to products that they're currently shipping, but there's a huge spectrum between initial idea and final product, and Apple has far less investment towards the idea end of the spectrum than any of their major competitors. By the time you can patent something, it's already towards the product end (and have you actually looked at the Apple patent portfolio? They patented a more efficient take-away pizza box, for example, which doesn't really tell you anything about pure research spending).

But if you think that R that is D-oriented doesn't "count", you are nothing but an intellectual effete.

It doesn't count because it's playing accounting games. The line between development and product is very blurry. Apple classifies a lot of things are R&D that other companies count as product development. This inflates Apple's R&D spending on the balance sheet, but means that you can't really compare. R&D is a pipeline and things always have to start closer to the pure research end. Most of Apple's R&D is building on pure research done by other organisations. This has changed a bit recently (particularly in machine learning), but they're still a long way behind most other big tech companies on research spending. Microsoft, until they restructured MSR a year or so ago, had the opposite problem: they were spending over $5bn/year on research and turning very little of it into products. Neither extreme is particularly healthy for a company. You need the research end to feed the pipeline, but then you need the pipeline from research to product.

Disclaimer: I work in a university and collaborate with Apple, Google, and Microsoft on several projects.

Comment Re:Weak/nonexistent punishments for faulty notices (Score 1) 81

All patent applications are signed under penalty of perjury. However, the US Patent and Trademark office disbanded its enforcement department in 1974. So, you can perjure yourself on a patent application with impunity.

Unless it's testimony in a criminal case, or the perjury trap in front of a grand jury, or something they want to prosecute like lying on your tax form, the Federal government is in general lassiez faire about perjury, or even encouraging of it with their reluctance to prosecute, especially perjury committed by a so-called intellectual property holder.

Comment Re:Maybe (Score 1) 204

The short of it, Jupiter moves things around; it's very good at scattering other bodies, even large ones. First it dragged outer populations into the inner solar system, then scattered inner solar system material out, and then on its retreat pulled outer solar system material back in. It's actually a very big deal that it did that, as it brought ice into the inner solar system.

Comment Re:Maybe (Score 2) 204

1. "Adjective nouns" need to have similarity to "noun" but aren't necessarily a subset. Gummy bears aren't a subset of bears either.

Gummy bears are not a scientific term. Besides, the IAU itself already uses the word dwarf in this manner. Dwarf stars, dwarf galaxies... but carved out an inexplicable exception for dwarf planets.

I'd like to see a citation on this. I highly doubt that you can simulate the formation of a solar system where multiple Mars analogues can coexist in the same orbit

False equivalency. There's a difference between "two Mars sized planets existing in the same orbit" and "Mars' orbit having been cleared". And more to the point, the biggest problem with the concept of Mars clearing its orbit is that its orbit was already largely cleared when it formed. According to our best models, Jupiter reached all the way in to around where Mars' orbit is today, and had cleared almost everything to around 1 AU. Earth and Venus accreted from planetesimals between each other. Mars accreted from planetary embryos ejected to the space in-between Earth and Jupiter. Without Jupiter's migration, simulations produce an Earth-sized Mars and several planetary embryos in the asteroid belt on eccentric / high inclination orbits, something akin to the situation between Neptune and Pluto - except with the embryos nearly Mars-sized.

3. In a geological sense yes. But the current definition of planets is based on orbital mechanics, after which Earth is a lot closer to Jupiter than to Ceres/Pluto.

Huh? By what aspect of orbital mechanics? By semimajor axis and velocity, Earth is much closer to Ceres than Jupiter. Are you talking inclination and eccentricity? Then we should boot Mars in favour of low inclination / eccentricity asteroids.

4. Hydro-static equilibrium as a dividing line is way worse. There are roughly 100 TNOs where we don't really know whether they are elliptical.

Hydrostatic equilibrium can be very easily estimated based on mass, which can be approximately deduced within a range of feasible albedos and densities, and very accurately deduced if the body has a moon. By contrast, it's almost impossible to estimate neighborhood clearing to any distance beyond Neptune, or at all in the case of extrasolar planets. Which, to reiterate, the IAU definition says aren't planets, even though they have an extrasolar planet working group.

We'd have to visit each and every one of them with a probe just to put them in the proper category.

This is utter nonsense.

Meanwhile, it's completely clear which bodies qualify for the "clearing its orbit" rule.

No, it's not. We have virtually no clue what lies in the outer reach of our solar system. As we speak there's a search for a new planet that could be as big as an ice giant. It's a huge open question as to whether it would have cleared its neighborhood, and it will be very difficult to ascertain.

All currently qualifying planets have roughly 99% or more of the mass in their orbit in themselves. Ceres has 30%.

You seem to have some weird concept going on that "semimajor axis = orbit". Ceres has nothing of significance in its orbit. The asteroids are not all in the same orbit. They're certainly more likely to cross each others orbits, but that's not the same thing.

And again, since you apparently missed it: the reason that the inner solar system is largely cleared except for the asteroid belt (and the reason that the latter exists) is Jupiter. Mars did not clear its own neighborhood.

5. The definition should be mutable. Why should a planet that gets ejected keep counting as a planet?

You seriously have to ask why something that hasn't changed but is in a different location shouldn't suddenly be declared to be something entirely different? If you take a rabbit to Canada does it suddenly become a dwarf rabbit?

6. I highly doubt life could form in a non-cleared orbit.

Once again, you're stuck on this misconception that the only orbital parameter that exists is the semimajor axis. And also apparently a notion that stable orbital resonances don't exist.

Orbits can come in a wide range of forms. If you want to see how crazy they get, check out Epimetheus and Janus ;)

As for a life bearing celestial in orbit around another (gas giant) planet: I don't think anybody feels bad about calling that one a moon? As in "Yavin 4".

The funny point with your example being, that whenever you illustrate a large round (hydrostatic equilibrium) moon in sci-fi - Star Wars, Star Trek, Avatar, whatever - people invariably keep calling it a planet and having to correct themselves. We inherently recognize "large, round object with relevant gravity = planet", and have to shoehorn our minds into not using that term.

7. "Within each other's periapsis and apoapsis" seems like a reasonable enough definition that neither Ceres nor Pluto qualify for.

Once again, you ignore most orbital elements (seriously, stop right now and go read the Wikipedia article on orbital elements). We don't live in a 2D solar system. And your notion is oversimplified even for 2D.

All of this, let alone other aspects such as mass ratios, resonance, metastability, etc. And it gets even more complicated when you view the solar system not as a 2-body problem but a multi-body problem. Then things like horseshoe orbits, Lagrangian points, etc come into play.

8. Yes that's silly but that'll probably be changed easily enough and has no effect on Pluto.

1) It's over a decade later. Where's the fix?
2) It's just a symptom of how horribly hasty and ill-thought-out their action was.

9. How are you planning to ascertain hydro-static equilibrium for an exoplanet if we can't even do it for Varuna.

What are you talking about? Varuna is the size of Ceres. The fact that it hasn't been declared a dwarf planet by the IAU is again a symptom of the IAU's dysfunction on this issue. See #18. By contrast, we'd have no snowball's chance in hell of identifying all potential orbit crossers for it.

The fact that you bring up Varuna makes me think that you feel it shouldn't be a planet because it's an oblate spheroid. If so, that just reveals yet another problem with your understanding: you need to go look up the definition of hydrostatic equilibrium. Hint: if Varuna wasn't an oblate spheroid, then it wouldn't be in hydrostatic equilibrium.

Comment Re:R&D (Score 1) 103

Apple spends serious coin on Research and Development; far more than their competition.

This is almost true, though the vast majority of Apple's R&D funding is firmly at the D end of the spectrum. IBM used to spend a lot more than Apple on research, though they've cut down a lot. Microsoft still does (around $5bn/year on MSR). These companies and Google (and Oracle, and so on) all throw grants at universities for research, which Apple doesn't. It wasn't until last the last few months that Apple even published any of their research.

Comment Re:AI Snippets... (Score 1) 330

In this respect, it's not really any different from stuff genetic algorithms have been doing for decades. If you have a set of executable tests that can tell if the algorithm is working correctly, then you can evolve something that will pass the tests. Of course, you have absolutely no idea how it will behave on inputs not covered by your tests.

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