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Comment Re:In MWI, this is obvious (Score 1) 152

Re: "becoming" mainstream, don't think it's there yet: I think something over 50% of practicing physicists accept it as of a few years ago, which is a change from even a decade ago. As for other interpretations, experiments like this one are making the CI much harder to swallow - instantaneous collapse? Really? FTL signaling?

Besides, Copenhagen is just a worse explanatory framework. If we're going to make any progress on quantum computation, thinking about what's _really_ going on rather than about mysterious shadows and collapse keeps things simple, local, and deterministic (in the multiversal sense of course) But you're right that something like Cramer's Transactional Interpretation could be the cause rather than multiple worlds. I just find it hard to stomach the idea of "backward causation".

Comment In MWI, this is obvious (Score 1) 152

In the many-worlds interpretation of QM, also called "QM without collapse", becoming more and more mainstream, this is a straightforward consequence of entanglement. When you measure the spin or polarization of your entangled particle, you become entangled with it, so in a sense all you're doing is discovering which "universe" you're in. And of course that universe is correlated with the corresponding other particle, no matter where it is now.

Comment Re:Speed penalty of encryption (Score 1) 124

Still fast enough for me.

Sure, I agree -- it's probably fast enough for most people, myself included. It's just the extra 1.5 sec of awake time (in your benchmark -- probably a lot less for real-world workflows, but if it happens on every mail sync, podcast download, it could multiply out to minutes of additional wake time per day) that bugs me because it will likely have an effect on battery life.

As hardware gets faster and (hopefully) less power-hungry, this should become less of an issue, so I expect I'll be happy to turn it on in a generation or two. I'm not there yet though. YMMV.

Comment Re:FDE on Android doesn't work as of yet (Score 1) 124

Whether in hardware or software, it's still a fair amount of computation, which means battery usage and latency. It has to affect the max IOPS, which means when the phone wakes up to do something, it'll stay awake for longer.

My N5's battery life is already barely acceptable; I'm not going to enable FDE on the chance it takes even a 5% or 10% hit.

Comment Re:This should be a given.. (Score 3, Informative) 47

The base-pair sequence of DNA determines its biological function. As you say, this sequence determines what kinds of proteins get made, including their exact shape (and more broadly how they behave).

But TFA is talking about the conformation (shape) of the DNA strand itself, not the protein structures that the DNA strand is used to make.

In living organisms, the long DNA molecule always forms a double-helix, irrespective of the base-pair sequence within the DNA. DNA double helices do actually twist and wrap into larger-scale structures: specifically by wrapping around histones, and then twisting into larger helices that eventually form chromosomes. There are hints that the DNA sequence itself is actually important in controlling how this twisting/packing happens (with ongoing research about how (innapropriately-named) "junk DNA" plays a crucial role). However, despite this influence between sequence and super-structure, DNA strands essentially are just forming double-helices at the lowest level: i.e. two complementary DNA strands are pairing up to make a really-long double-helix.

What TFA is talking about is a field called "DNA nanotechnology", where researchers synthesize non-natural DNA sequences. If cleverly designed, these sequences will, when they do their usual base-pairing, form a structure more complex than the traditional "really-long double-helix". The structures that are designed do not occur naturally. People have created some really complex structures, made entirely using DNA. Again, these are structures made out of DNA (not structures that DNA generates). You can see some examples by searching for "DNA origami". E.g. one of the famous structures was to create a nano-sized smiley face; others have 3D geometric shapes, nano-boxes and bottles, gear-like constructs, and all kinds of other things.

The 'trick' is to violate the assumptions of DNA base-pairing that occur in nature. In living cells, DNA sequences are created as two long complementary strands, which pair up with each other. The idea in DNA nanotechnology is to create an assortment of strands. None of the strands are perfectly complementary to each other, but 'sub-regions' of some strands are complementary to 'sub-regions' on other strands. As they start pairing-up with each other, this creates cross-connections between all the various strands. The end result (if your design is done correctly) is that the strands spontaneously form a ver well-defined 3D structure, with nanoscale precision. The advantage of this "self-assembly" is that you get billions of copies of the intended structure forming spontaneously and rapidly. Very cool stuff.

This kind of thing has been ongoing since 2006 at least. TFA erroneously implies that this most recent publication invented the field. Actually, this most recent publication is some nice work about how the design process can be made more robust (and software-automated). So, it's a fine paper, but certainly not the first demonstration of artificial 3D DNA nano-objects.

Comment Non-deterministic sort (Score 4, Interesting) 195

Human sorting tends to be rather ad-hoc, and this isn't necessarily a bad thing. Yes, if someone is sorting a large number of objects/papers according to a simple criterion, then they are likely to be implementing a version of some sort of formal searching algorithm... But one of the interesting things about a human sorting things is that they can, and do, leverage some of their intellect to improve the sorting. Examples:
1. Change sorting algorithm partway through, or use different algorithms on different subsets of the task. E.g. if you are sorting documents in a random order and suddenly notice a run that are all roughly in order, you'll intuitively switch to a different algorithm for that bunch. In fact, humans very often sub-divide the problem at large into stacks, and sub-sort each stack using a different algorithm, before finally combining the result. This is also relevant since sometimes you actually need to change your sorting target halfway through a sort (when you discover a new category of document/item; or when you realize that a different sorting order will ultimately be more useful for the high-level purpose you're trying to achieve; ...).
2. Pattern matching. Humans are good at discerning patterns. So we may notice that the documents are not really random, but have some inherent order (e.g. the stack is somewhat temporally ordered, but items for each given day are reversed or semi-random). We can exploit this to minimizing the sorting effort.
3. Memory. Even though humans can't juggle too many different items in their head at once, we're smart enough that we encounter an item, we can recall having seen similar items. Our visual memory also allows us to home-in on the right part of a semi-sorted stack in order to group like items.

The end result is a sort that is rather non-deterministic, but ultimately successful. It isn't necessarily optimal for the given problem space, but conversely their human intellect is allowing them to generate lots of shortcuts during the sorting problem. (By which I mean, a machine limited to paper-pushing at human speed, but implementing a single formal algorithm, would take longer to finish the sort... Of course in reality mechanized/computerized sorting is faster because each machine operation is faster than the human equivalent.)

Submission + - Alternatives to Slashdot post beta? 8

An anonymous reader writes: Like many Slashdotters, I intend to stop visiting Slashdot after the beta changeover. After years of steady decline in the quality of discussions here, the beta will be the last straw. What sites alternative to Slashdot have others found? The best I have found has been, but it has been a while since I've looked for tech discussion sites.

Submission + - Slashdot BETA Discussion ( 60

mugnyte writes: With Slashdot's recent restyled "BETA" slowly rolled to most users, there's been a lot of griping about the changes. This is nothing new, as past style changes have had similar effects. However, this pass there are significant usability changes: A narrower read pane, limited moderation filtering, and several color/size/font adjustments. BETA implies not yet complete, so taking that cue — please list your specific, detailed opinoins, one per comment, and let's use the best part of slashdot (the moderation system) to raise the attention to these. Change can be jarring, but let's focus on the true usability differences with the new style.

You don't have to know how the computer works, just how to work the computer.