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Before it gets out of control... I hope you realise that quoting "Science Daily" in the context of science is pretty much like using Daily Mail as your reference news agency?

I was just going to post the same story. Here is BTW a video of the intended type of robot: https://www.youtube.com/watch?v=OHo32JrkDRk&feature=youtu.be

I always feel like people make too big a deal out of entanglement. In my opinion it is just a combination of a conserved quantity and an initial lack of knowledge. Imagine that I had a machine that always creates one blue and one red ping-pong ball at the same time (|b > and |r > respectively). The machine now puts both balls into identical packages (so I cannot observe them) and one of the packages is sent to Tokio. I did not know which ball was sent to Tokio and which stayed with me - they are in a superposition (|br >+|rb >), meaning that either the blue ball is with me and the red one in Tokio or vice versa - they are entangled. So far no magic has happened. Now I call my friend in Tokio who got the ball: "What color was the ball you received in that package?" He replies: "The ball that I got was blue. Why did you send me ball in the first place?" Now, the fact that he told me makes the superpositon wavefunction collapse (yes, that is what the Copenhagen interpretation would tell us). As a result I know without opening my box that it contains a red ball. But this is really because there is an underlying conservation law and because now I know the other state. I don't see how just looking at the conserved quantity I am in a timeless state outside of the 'universe' - this is just one way of interpreting it. By the way, the wave function for my box with the undetermined ball does not collapse when the other ball is observed by my friend in Tokio. Only when he tells me does the wavefunction collapse - he did not even know that I had a complementary ball. On the other hand if he knew about the way the experiment was conducted then he would have known that I had to have a red ball - the wavefunction collapses as soon as he observed his ball. For him it is determined that my ball must be red. For me however the superposition is intact until he tells me. ;-)

Sorry, Johannes, you just develop a simple hidden-parameters theory and it's experimentally proven that these don't work. Entangeled states are neither the blue nor the red ball they are really bluered (or redblue) till the point the measurement is done.

Hm, to me this looks like a bad joke... The "emergent time" concept used is still the old proposal by Page and Whotters where time emerges from something fundamentally unobservable (the wave function of the Universe). That's as good as claiming that time emerges from God. If I understand correctly, the paper now deals with the situation where a finite system is taken as "Mini-Universe" and the experimentalist in the lab can play "God of the Mini-Universe". This works, of course, but it doesn't really tell us anything about emergent time, does it?

Actually, it has not been proven conclusively that hidden variable theories don' work - although this is the opinion of most physicists these days. But a non-local hidden variable would still be allowed - I don't see why that could not be equivalent to a conserved quantity within the system. As far as the two balls go it is fine to say they are undetermined instead of saying they are in bluered or redblue state - for all intents and purposes it does not affect us (because if it would the wavefunction would have collapsed) so we can't say anything about it in the first place.

Non-local hidden variables may work, but in my opinion they don't add anything to the picture. The (at least to non-physicists) contraintuitive fact that there cannot be a variable that determines ab initio the color of the ball going to Tokio will remain (in your example this may not even be true since the example is too simple...).

Your link points to a restricted LinkedIn page... Here's the original link: http://www.15inno.com/2010/06/07/apple/

A pretty standard Apple-o-getic (ah ah) blog post. How many times does the guy say 'I like Apple'? Anyway, I'm having a hard time understanding the point he is trying to make. Apple should open up its innovation? It shouldn't because they are so hip, cool, a 'unique company' and an 'exception to the rule'? Mah..

I think the point is the guy bashes the "open innovation theory" (whatever the theory is) with his main argument being that Apple is not open and at the same time very successful.

Great! Women perhaps are not more intelligent as individuals, but now at least they have more collective intelligence... Interesting research topic, though, but I doubt that any of these results can be generalized to real live situations.

Maybe by passing the message to ensure some men understand it would be their interest to have (more) women in their teams ? No problem at the ACT, this maybe why it works so well ? :-))

How is this any different from the slew of existing WYSISYG LaTeX-based editors? E.g., http://www.texmacs.org/

wow!!!!!!!!!!!! you can write equations!!!!!!!!!!

"What you need: - A LaTeX installation" I guess you can buy one in Apple Store... no?

Q1: For the time being, for what purposes computers are mainly used on-board?

for navigation, control, data handling and so on .... why?

Well, because the point is to identify an application in which such computers would do the job... That could be either an existing application which can be done sufficiently well by such computers or a completely new application which is not already there for instance because of some power consumption constraints... Q2 would be then: for which of these purposes strict determinism of the results is not crucial? As the answer to this may not be obvious, a potential study could address this very issue. For instance one can consider on-board navigation systems with limited accuracy... I may be talking bullshit now, but perhaps in some applications it doesn't matter whether a satellite flies on the exact route but +/-10km to the left/right? ...and so on for the other systems. Another thing is understanding what exactly this probabilistic computing is, and what can be achieved using it (like the result is probabilistic but falls within a defined range of precision), etc. Did they build a complete chip or at least a sub-circiut, or still only logic gates...

Satellites use old CPUs also because with the trend of going for higher power modern CPUs are not very convenient from a system design point of view (TBC)... as a consequence the constraints put on on-board algorithms can be demanding. I agree with you that double precision might just not be necessary for a number of applications (navigation also), but I guess we are not talking about 10km as an absolute value, rather to a relative error that can be tolerated at level of (say) 10^-6. All in all you are right a first study should assess what application this would be useful at all.. and at what precision / power levels

The interest of this can be a high fault tolerance for some math operations, ... which would have for effect to simplify the job of coders! I don't think this is a good idea regarding power consumption for CPU (strictly speaking). The reason we use old chip is just a matter of qualification for space, not power. For instance a LEON Sparc (e.g. use on some platform for ESA) consumes something like 5mW/MHz so it is definitely not were an engineer will look for some power saving considering a usual 10-15kW spacecraft

What about speed then? Seven time faster could allow some real time navigation at higher speed (e.g. velocity of a terminal guidance for an asteroid impactor is limited to 10 km/s ... would a higher velocity be possible with faster processors?) Another issue is the radiation tolerance of the technology ... if the PCMOS are more tolerant to radiation they could get more easily space qualified.....