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Comment Re:Okay, if they think that will work (Score 1) 67

Yep, what made the movie work was that it was actually good Sci-Fi, as action movie Sci-Fi goes (which has little enough to do with written SF). Good character development, a bit of actual suspense, you cared about the characters, etc. Even without the parody stuff, it was better than the Star Wars prequels or half the Star Trek movies.

It was genre-savvy satire, more than simple parody, and it was good. Not sure how you could turn it into a series though, unless they're going to make the Galaxy Quest series that was the backstory to the movie, which could be fun for one season.

Comment Re:Wait, physics doesn't work either? (Score 1) 181

Everything in physics works in both time directions (you have to swap some signs +/- when you reverse time, but it all works). Causality as "a chain of related events over time" is a real thing, even if what you place in the chain may be somewhat arbitrary, but the direction, which is cause and which is effect, isn't so well defined. At the QM scale it's arbitrary. In human experience, a film played in one direction looks different than in the other because, ultimately, of the energy input from the Sun breaking the symmetry.

Comment Re:Wait, physics doesn't work either? (Score 1) 181

our "underlying state" seems equivalent to a "hidden variables" theory.

No, it's just the sloppiness of English trying to represent math, or perhaps my lack of facility with one of those in trying to craft a metaphor.

To extend my above metaphor: there's no hidden "observable" state. The underlying state is not "this one spin-up, that one spin-down" (which is forbidden), because there are not electron identities anyhow, but instead "exactly one of them is spin-up". As you measure one of them, there are now three entangled things: the two electrons and your detector, and there's a set of allowed observables given all that, when you add the second detector, now there are 4 entangled items. It's not non-local, it's just a constraining of the set of allowed states for the complete system.

Comment Re:Wait, physics doesn't work either? (Score 4, Interesting) 181

The real question is - exactly wtf is entanglement anyway? I can find lots to read about what it looks like and how it behaves... but what's the underlying mechanism? Is there even the most speculative explanation of it?

Here's the best answer I can give you - I think it's true, and not so over-simplified as to be wrong.

The universe has some underlying state. We don't have direct access to that state - not only is it not directly observable, it's not directly related in any intuitive way to the state we can observe. There's this arbirtary-seeming transform between underlying state and what we observe (it only seems odd or arbitrary because all our intuitions are based on human-scale observables, and are not at all directly informed by this underlying state). This underlying state seems to be well-defined and deterministic, forwards and backwards in time. The observable universe is not.

Entanglement is a feature of how observations relate to underlying state - a feature of the transform. In very simple experiments we can measure specific properties of, say, an electron. We can't measure all of them, for a given electron, because the transform just doesn't work that way, but we can measure some. However, that's deceptive, because you can't really track that property of that electron over time, in non-trivial cases. If e.g. two electrons interact, become entangled, your observations are now a function of both electrons' underlying state, and that's a different transform from 2 non-entangled electrons.

There are two key concepts here. The first is that the whole notion of "particle" is a handy but false oversimplification. It can lead you to all sorts of false intuitions about how particles behave. Fundamentally, individual e.g. electrons don't have unique identities. The underlying state is a single electron field, which other fields can interact with, in a way that can sometimes be simplified as "particle interactions", for a simpler mental model, but you can't go too deep with that model. An example: "two electrons collide in an accelerator, and two electrons leave, which is which?" That question is "not even wrong", it's just nonsense. Thinking of electrons as billiard balls colliding is simply not a helpful model, as it just misses the point of the interaction.

"Entanglement" happens just when the "particle" mental model fails: you can no longer pick two disjoint areas in the electron field and consider them as independent "electrons", but instead you have to reason about two areas which may be quite disconnected in space and time. E.g., you might know for sure that one electron is spin-up, and one spin-down, but have 0 information about which is which. None of that matters to the underlying state: there's just one electron field, and the only truly correct way to reason about it it to reason about the whole field all the time, and so this is only half of "WTF is entanglement".

The second concept gets too much into the math to explain well, but in a hand-wavy way it's this: "what is measurement?". There are older interpretations about measurement causing wavestate collapse and so on, but they're wrong because of that word "cause". Measurement is simply the observer becoming entangled with the observed. Measuring one entangled electron doesn't "cause" the other electron to do or become anything. The underlying state is unchanged, which is why there's no faster-than-light effect. In some cases, this is an overly pedantic distinction, but it matters when the difference between QM and intuition matters. In a two-slit experiment where you see an interference pattern at your detector, if you add a measuring device to one slit suddenly you don't see that interference pattern. Informally we might say the second observer "caused" this change, but formally that's wrong, it's just that a system with 2 slits and 2 detectors behaves differently from a system with 2 slits and one detector, and it doesn't matter which detector the electron passes first, because (see above) an "electron" as a discrete particle is fiction anyway, and both detectors are entangled with the electron field already, or they couldn't measure an electron anyhow.

Comment Re:What's the real problem? (Score 1) 188

It's not a question of open vs proprietary, it's a question of buying support from the right people. If you're running code that wasn't developed in house, then you probably don't want to be supporting it in house either. You want an SLA with penalty clauses with someone who will fix it when it breaks. If it's open source, that just means that you have more options in terms of who will support it if the level of support that you want involves fixing bugs and adding features.

Comment Re:Comparison? (Score 1) 239

I was going to comment that I'd expect some variation depending on the quality of the venue, but then I looked at the list. Most of the places that they looked at are top-tier publications, so it's pretty depressing. That said, they are focussing on the wrong aspect of reproducibility. The real metric should be, given the paper, can someone else recreate your work. And I suspect that even more papers fail on that. At the ASPLOS panel discussion this year, there was a proposal that PhD students should spend their first year reproducing some published result. We often do something similar for undergraduate projects (take an idea from a paper, reimplement it, see if your results support their claim).

Comment Re:That's gonna be a nope (Score 1) 123

There's an increasing amount of good open source software on Android that can replace the Google crap. I'm now using:
  • OSMAnd, which is actually the reason that I'm still using Android. Best mobile maps app (Nokia's Here is better for driving, but not for walking): offline vector maps that are small enough that you can fit a few entire countries on the phone, offline routing, and so on. The version on the Play store is not as good. I used to use the free version on Play, but actually donated $10 to them after discovering the F-Droid version.
  • K9 Mail is a pretty reasonable mail client.
  • Standalone Calendar is a fork of the AOSP calendar (now replaced by the Google Calendar app on most devices). The UI is not great, but I've not found any mobile calendar app that is. I mostly just use the Calendar Widget on my home screen to look at upcoming events and DAVDroid to sync with my CalDAV / CardDAV server (which also syncs with my laptop).
  • Open Camera is definitely a geek's calendar app: far more configurable settings than the stock one, but the UI isn't quite as polished.
  • KQSMS provides a nicer interface to SMS. For backups, SMS Backup+ will sync SMS with an IMAP server.
  • AnySoftKeyboard provides a configurable set of keyboard layouts and, unlike the Google version, doesn't appear to be spyware.
  • Firefox on Android is actually pretty nice, and the addition of the Self Destructing Cookies addon makes it a lot nicer than any other Android browser I've tried (cookies are automatically deleted when you navigate away from a page, tracking cookies are deleted periodically while on the page. There's an undo button if you realised that you actually wanted them for one site, and and you can then whitelist just those ones).

I'd love to have a company adopt some of these, polish the UI a bit, and provide an Android phone that ships with them by default, instead of the Google stuff.

Comment Re:is the problem not ADOBE FLASH? (Score 1) 220

It's not just that they're complex. The code for decoding them is also not usually with security in mind. Remember that libjpeg was written in an era when a 486 was a high-end machine and all three sites on the web that contained images were pretty trustworthy. It needed to be able to decode and display the image in a limited amount of RAM, on a slow CPU, without the user complaining about the time it took (and it didn't - it was slow, and we complained). Modern CPUs are fast enough that even an interpreted JavaScript PNG or JPEG decoder is fast enough, but video decoding (unless offloaded to an accelerator) is still pretty CPU-intensive, so now video decoders are written with performance as the overriding goal and security a distant second. Doing proper bounds checks costs cycles (and, worse, often breaks autovectorisation), so gets overlooked.

Comment Re:Risk Tolerance not that High (Score 1) 95

That is surprising since claims regarding the failings of our schools are so prevalent in media and society as a whole.

I agree - it's the same here in Canada - but I would attribute that to attempts to improve the system using new techniques which have never been proven to work better than the system they replaced. Worse the reason given for using the new system is that the previous system is "old and archaic". You do not replace something simply because it is old, you replace it when you have something better.

Many of the new teaching techniques I have seen work not because of their brilliance - indeed many are half-baked ideas - but because the person who came up with them is clearly enthusiastic about the approach and communicates that to their students when using the technique. To really show the worth of a new teaching technique it needs to be used by someone who is not particularly keen about it (but neither hostile to it). The reason that we keep seeing all these different approaches which then get withdrawn and/or derided is because this is the hurdle they almost all fail: they do not work with a less motivated tecaher

Comment Re:Ban all NUKES NOW - accident waiting to happen (Score 1) 161

Truly, as the sun never stops shining and the wind never stops blowing.

It will eventually. I suspect there will still be fossil fuels available when that day comes, as we'll have moved fully to solar and fusion (but I repeat myself) before we run out.

Comment Re:So if I'm CEO at a tech company, block google? (Score 1) 179

Google already knows who you work for. Google already knows what you're working on. Heck, if you have an Android with default settings, they have all your whiteboard pictures. This likely isn't a "candidate identification" tool, but rather a way to get people more interested in saying "yes" to the recruiter - oh, those were fun puzzles, maybe I do want to work for Google.

Comment Re:Exaggeration is not Necessary (Score 1) 356

The rise will stop. There is a finite amount of water on the planet that can end up in the oceans.

True but the sea could rise quite a bit before we get to that if you have a look at the sea level over the past 500 million years. Interestingly it seems that we live in a time of surprisingly low sea levels. A 200 metre sea rise would affect quite a few people.

The rule on staying alive as a program manager is to give 'em a number or give 'em a date, but never give 'em both at once.