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Comment Re:He stole, he got arrested (Score 4, Informative) 674

To plug your phone into the wall should not be to get arrested, unless there is a gigantic sign saying "PLUGGING INTO THIS IS PROHIBITED." [...] What's more, it *shouldn't* be prohibited unless it creates problems.

You do realise that this is exactly how it was, right? There was a sign, and it exists because plugging in might damage your equipment. From TFA:

Electricity sockets on Overground trains are clearly marked with the words: âoecleaners use only and not for public useâ.

On a forum dedicated to the London Underground, members have pointed out that plug sockets on the trains are for cleaning equipment deployed when trains are in depots. They recommend not charging electronic equipment as there is a risk of power surge: âoeIf something was directly plugged into it (for example a standard computer, or a laptop without a battery in) the equipment would probably be damaged at any section gaps where the power supply changes from one substation to another!â

Comment Re:No programming? (Score 5, Insightful) 200

The behavior emerged through evolution and was encoded in the neurons by nature

What has been implemented in this robot has nothing to do with biological neurons of C. elegans.

The robot uses integrate-and-fire neurons. The "signal" sent from pre- to postsynaptic neuron is an integer equal to the number of connection between the neurons in the real worm. If the sum of input exceeds a threshold, the neuron "fires" (sidenote: right here's a bit of programming: how did the threshold values get chosen?).

C. elegans neurons do not "fire" (they are not spiking neurons and lack Na+ channels) but use calcium-based analog signals.

The body does matter too. C elegans has muscles on either side that it contracts alternately to move in a sinusoidal fashion. Not wheels. C elegans locomotion does not work like wheeled locomotion.

So, yes, you are right, C elegans neurons encode behaviour appropriate for a C elegans body given the biology of the neurons available here. None of this, however, makes it into this robot. An abstraction of the connectome does (C elegans has both electrical and chemical synapses; that distinction seems to be lost here too) and that's it.

It is kinda cool that the connectome does seem to naturally implement some basic response patterns; but given that muscles have been replaced by wheels, I'm not sure how meaningful that actually is.

Comment Re:Mapping the Nematode? (Score 1) 44

Could a complete mapping of the neural network be accomplished?

The C elegans brain has been completely mapped in terms of connectivity a long time ago. See for instance:

Would it be possible to artificially trigger a neuron to verify the mapping?

Interesting thought - I'm not aware of anyone having done that but it's been a while since I followed the C elegans literature closely.

C elegans is pressurised, so you can't easily stick an electrode (assuming you had one small enough) next to your neuron of choice to stimulate it. Maybe you could make a secific neuron become light-sensistive and use optical stimulation (the worm's transparent, so that helps) but again, not sure anyone has ever attempted that in C elegans.

The converse has been done repeatedly though: either ablate a neuron using a laser or design a mutant that won't have it in the first place (remember that the C elegans genome is completely mapped too) and see how it affects behaviour.

Comment I have a much neater solution. (Score 4, Funny) 157

Someone from the future travels to the past, changes something fundamental and the universe slips into an alternate reality from which it can never return and in which no event can be expected to unfold as it did in the original.

Not only will this by definition never be inconsistent with the EU, it will give the writers ways of amusingly rehashing old stories by subtly altering some key elements things, like who gets to die of radiation while saving the crew. Maybe, in Episode VII, Luke will hack off Vader's hand?


Comment Re:Not possible (Score 1) 612

Physics is not accessible to mathematics

This is very much still an active topic of discussion, actually, and certainly not as settled or clear-cut as you seem to think. You can start with Wigner's essay.

And just to provide the opposite viewpoint to yours, some people will of course argue that physical reality is mathematical.

Comment Re:I deciphered it last month. (Score 1) 170

I'm certain that "words" in the manuscript do not represent words in the original language. They are merely chunks of ciphered text, which explains the unusually homogeneous word lengths, for one thing. I believe the length of the ciphered words is thus arbitrary and chosen by the person doing the ciphering. That also explains how word length and spacing can be perfectly justified and fit along the varied shape of images

Now that you mention it... it's obviously an early entry to the IOCCC.

Comment Re: wait (Score 4, Informative) 259

It isn't clear here whether the papers in question were the pre- or post-editing versions

They are going after the final, published versions (including Elsevier formatting and all), commercial use of accepted manuscripts, systematic distribution and the like (some of which applies to In other words, what you said was fair game still is - you are allowed to share the accepted manuscript with others (including on your website where Google Scholar will pick it up and render it discoverable in a matter of days, so it's not like this restricts you), you (or anyone else) just can't make money off it and you can't use their typesetting.

For the accepted manuscript version, let me just quote from Elsevier's author rights:

Elsevier believes that individual authors should be able to distribute their AAMs for their personal voluntary needs and interests, e.g. posting to their websites or their institutionâ(TM)s repository, e-mailing to colleagues. However, our policies differ regarding the systematic aggregation or distribution of AAMs to ensure the sustainability of the journals to which AAMs are submitted. Therefore, deposit in, or posting to, subject-oriented or centralized repositories (such as PubMed Central), or institutional repositories with systematic posting mandates is permitted only under specific agreements between Elsevier and the repository, agency or institution, and only consistent with the publisherâ(TM)s policies concerning such repositories. Voluntary posting of AAMs in the arXiv subject repository is permitted.

So you can see how falls foul of this while your right to share your work does not.

(Some of my papers are published in Elsevier journals - they are however also all open access. In case you're wondering.)

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