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Comment Re:Cool! (Score 1) 446

- GR breaks down when you go to quantum levels

Could you be more specific? There are plenty of successful marriages of GR and QM. For example quantum field theories such as QED, QCD etc.

- GR does not fully describe black holes (particularly their horizon and the singularity)

No one has seen the event horizon or the inside of a black hole so we don't know if the GR predictions matches reality or not. (And, if GR is correct, nothing beyond the horizon can be studied). The things we have checked (like gravitational waves) matches.

- GR is incomplete with regards to explaining the expansion of the universe (the discrepancy is called Dark Energy)

Dark Energy is a proposed solution to make the observations match the predictions. So, if dark energy is found there is no conflict with GR. Calling GR incomplete is a bit unfair since it isn't a theory of everything (and isn't supposed to be), just a theory of the interaction between matter/energy and spacetime. It makes no predictions of how much or which type of matter should exist.

I'd say the original statement holds. No cracks have been found yet.

Comment Re:Nerver try to predict the future (Score 1) 250

I was surprised to see Apple on the list. Most of their revenue (69%) comes from one product single line, the iPhone. People change phones every couple of years and if it goes out of fashion, the fall of Apple could be very quick. They would probably lose a lot on all their other sales as well since the main point of buying a Mac/iPad is the common ecosystem/vendor lock-in. Apple has basically put all eggs in one basket and if it breaks, they could be of no importance in no time.

Really, the more I think of it, Apple has nothing that could not be replaced in a couple of years. Compare that to Microsoft. People are still buying their stuff despite Microsofts best efforts at stopping them (W8 and 10, ribbons etc).

Comment Re:Responsible party? (Score 4, Interesting) 129

In the thread you linked to, John Layt (KDE dude near the bottom of the thread) explains how the Outreach Program for Women actually worked. No money was "blown" on the program. It was just a timing mismatch of the cash flows from the sponsors to the interns which Gnome used it's own money to cover. So, a "cost" one year should be matched by a "income" next year (as long as the sponsor pays up).

The problem was that the program got too popular for the foundation to handle with their existing routines (see some of Sri's posts). It seems the cash flow problem had nothing to do with Karen but with inadequate administration.

Comment UCLA News (Score 3, Informative) 71

Haven't found any scientific article yet but here is the news page from UCLA:

In short, they found graphite in a crystal and the graphite has a carbon 12 to carbon 13 ratio which indicates biological origin.

So, the current status is "plausible" but if someone comes up with another explanation it is "busted".

Comment Re:Best Keyboard (Score 1) 459

I wish I had mod points! That's one of the simplest solutions I've heard of yet and I will give it a try. I have a slight case of emacs pinkie and would even consider switching the left and right hands to get all the important keys in the middle (asdf on right hand, jkl on left). That would of course require some serious mental gymnastics to get used to though...

Do you have any examples of small keyboards with GOOD keys?

Thanks for the suggestions!

Comment Re:Information (Score 1) 242

I thought the main point of the copenhagen interpretation was the instrumentalist approach. That is, the mathematical description should not be considered a description of reality but just a tool for calculating probabilities of real events. So, these supposed issues with 'conscious observers' do not apply. There is no real wavefunction and no real collapse. It's just a mathematical description.

But, even if you take a realist approach to the standard QM theory and argue that the wavefunction is real, conscious observers are still not required. It is a well known and tested fact that you do not need a conscious observer to collapse a wavefunction. Take your classical double slit experiment, put a measuring device by one of the slits to force a collapse of the wavefunction (and thus no interference pattern). Now, put a piece of tape over your measuring devices display so no conscious observer can see it. The result doesn't change.

Yes, a philosopher or someone taking the collapse notion a bit too seriously would argue that the entire system (detector, double slits, measuring device etc) is in a mixed state until the observer checks the output on the detector but that is quite a stretch. (See the whole Schrodingers Cat debate)

All measuring devices are huge from a quantum mechanical standpoint. We can barely make calculations on large objects like molecules (and that with rather heavy approximations) and measuring devices typically consist of lots and lots of molecules. It is currently quite impossible to write down a quantum mechanical description of even a simple experiment with a simple measuring device. If we could, maybe we would see that the that the addition of a measuring device causes a mixed state to evolve into a pure state, just by the laws of QM. No conscious observers would then be necessary and the 'collapse' would be just a consequence of the theory. However, making those calculations is way too complicated and far from what we can currently do.

So, neither the instrumentalist or realist interpretation of standard QM theory requires conscious observers.

Comment Wikipedia (Score 1) 600

Could this really be that great? I remember how difficult quantum field theory was and I have always wished for an easier way to do it (so I could actually understand more of it). But, if these methods have been around since the 80s, why haven't I heard about them before?

So, first stop Wikipedia

"When the volume of the amplituhedron is calculated in N=4 supersymmetric Yang-Mills theory, it perfectly describes the scattering patterns of subatomic particles."

OK, sounds good.

"Since the N=4 supersymmetric Yang-Mills theory is a toy theory that does not describe the real world, the relevance of this theory to the real world is currently unknown, but it provides promising directions for research into theories about the real world."

Oh, crap. So, it's just another toy theory with promising properties which has not been applied to the real world yet? That's not very interesting since there are plenty of such toy theories. It would be really cool if one of them turned out to work for the real universe as well but that seems to be a very hard nut to crack. I personally hope Lisis E8 theory would be the right one just because Lie groups are fun and the pictures are pretty.

Comment Music competitions (Score 1) 51

It reminds me of this:

In short, people were bad at guessing who won the competition when they could only hear the music and not see the performers. Professional judges were just as bad as novices (worse when they could see the performance but just as bad when they could only hear it).

Interesting stuff.

Comment Re:you had me at... (Score 1) 404

I for one like the idea of an optionally typed language. I work with hybrid C++/Python programming so I have experienced the pros and cons of typed vs untyped languages.

In general, I much prefer Python to C++ because of the ease and speed of implementing stuff. But, Pythons performance is lacking so I need C++ for that. My perfect language would have the speed of C++ but the ease and implementation speed of Python. Cython is one such language which is basically compiled Python with optional types. The optional types allows for a lot of extra compiler optimisations and it gives a huge performance boost. I haven't used it for anything "real" though because it uses language extensions and is thus incompatible with pure Python. Once I've converted something to Cython, I'm stuck with the much slower debug/compile/run cycle and I've lost some of Pythons speed and ease. Ideally, Python would some day add optional type info so I could run cython code in the (slow) Python interpretor and compile it once I'm ready to release it. For the moment, I prefer the approach of Shedskin but that's another story.

So, my perfect language would have optional typing and optional compiling when maximum performance was needed. I have no idea if Dao is such a language though.


Cold Spring Linked To Dramatic Sea Ice Loss 422

hrvatska writes "An article at Weather Underground reports that researchers have linked large snowstorms and cold spring weather across Britain and large parts of Europe and North America to the dramatic loss of Arctic sea ice. It is thought that the Arctic ice loss adds heat to the ocean and atmosphere, which shifts the position of the jet stream, allowing cold air from the Arctic to plunge much further south. Researchers expect that a warming Arctic ocean will drive more extreme weather in North America and Europe (abstract)."

Comment Re:Wouldn't it be good news? (Score 1) 468

So, why does the Research council of Norways own article say (close to the bottom, UPDATE in bold):

"All research results in this news brief have not yet been published. The research has been completed, so this news brief is a synthesis consisting of both published and thus far unpublished findings. In consultation and collaboration with the researcher, the Research Council has chosen to release this news at the completion of the research project because the project is of general interest. However, the Council releases this news with the caveat that the findings outlined in this news brief have yet to be verified and that the results will only become significant once they are confirmed by other studies. For further information please visit CICERO"

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