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Comment Re:What's the _actual_ algorithm. (Score 1) 77

With 43 papers on Arxiv answering to that author surname, I suspect that the paper will be there some day. (That search's most recent result was "1. arXiv:1512.02135 Soficity, short cycles and the Higman group " ; other papers in the results relate to work on primes, so it looks as if this is the correct author.)

Linking to that, when the (draft) paper goes up is much more appropriate than mucking around with emailing pre-prints.

Comment Find the actual paper, not gizmodo crap. (Score 1) 166

Well, it looks as if no-one has bothered to find the actual source, instead of relying on some clickbait advertising site's cut'n'paste.

Well, that took about 3 minutes. The paper is in Science. If you don't have a subscription, you'll need to try something like Sci-hub.

Abstract: The history of atmospheric O2 partial pressures (P-O2) is inextricably linked to the coevolution of life and Earthâ(TM)s biogeochemical cycles. Reconstructions of past P-O2 rely on models and proxies but often markedly disagree. We present a record of P-O2 reconstructed using O2 / N2 ratios from ancient air trapped in ice. This record indicates that P-O2 declined by 7 per mil (0.7%) over the past 800,000 years, requiring that O2 sinks were ~2% larger than sources. This decline is consistent with changes in burial and weathering fluxes of organic carbon and pyrite driven by either Neogene cooling or increasing Pleistocene erosion rates. The 800,000-year record of steady average carbon dioxide partial pressures (P-CO2) but declining P-O2 provides distinctive evidence that a silicate weathering feedback stabilizes P-CO2 on million-year time scales.

So, for starters, it's evident that the researchers (though not the non-geologists at Giz-wotsit) appreciate the difference between erosion (the mechanical break up and movement of rock) and weathering (the chemical alteration of the minerals that comprise that weathered rock). They're also well aware that with two processes in place, and a critical factor (temperature) being considerably variable in both time and space, then deconvolving what is actually going on is going to be quite difficult, if not impossible without more data (perhaps from looking at mineralogy variations in sediments deposited in different areas with different mean temperatures.

contrary to the impression that many people have got (I guess from Giz-thingy, the researchers were specifically not looking at air bubbles in the ice, but at air dissolved in the ice. "(ii) Only analyses of bubble-free ice with clathrates were considered. (para 3)" (Do I need to remind people that "clathrate" does not only mean "crystalline compound of hydrocarbon gases and water"? Probably.) They also look at the argon - nitrogen ratio to monitor for changes in the dissolution of oxygen, argon and nitrogen relative to each other due to changes in the immediate environment of the accumulating snowpack.

Could this be an artefact of measurement? Well, they've certainly considered (and rejected) that : "Our hypothesis is further supported by the observation that data from all four ice cores individually exhibit the same general trends and magnitudes of decreasing dO2 /N2 with time (table S3), even though each was drilled, stored, and analyzed differently." So, they think it's a genuine atmospheric change.

CO2 recorded in the cores does not change sufficiently or sufficiently consistently to explain the changes observed, so they ascribe a lot of the change to the weathering of pyrite - a reduced iron mineral - into oxidised iron salts ("rust", or iron-rich clays e.g. the glaucony/ glauconite familes).

There's a reason that people write papers, instead of using journalists to report their findings. It's because the details matter.

Comment Re:Just like google glass (Score 1) 92

Having at different times had fairly strong alkali (fortunately not strong enough to burn, just to hurt. A lot.) spray into my eyes in the darkroom, and picked metal shards out of the front surface of my sun glasses, I'm perfectly fine with dorky glasses for regular wear and Triplex safety glasses for when I'm actually working.

You don't like dorky glasses? Well, they're you're eyes. Enjoy them while you've got them.

Comment Re:Am I reading this right? (Score 1) 78

if we were good at maintaining LOX-composite compatibility, we'd be making the stages themselves out of composites rather than aluminum.

I get that LOX plus composites are an un-good mix. But even with passivation, are aluminium and LOX really that much better? There's still a nerve-twanging amount of free energy in there.

Comment Not that I use Reddit, but ... (Score 1) 382

Actually, despite it's frequent mentions, I'm not even sure what Reddit's address is, but that's a by the by.

If people are using it for advice about things like IT, then it's obviously not an American company, with any American employees (subject to TLA pressure), and none of it's servers would be located in US jurisdictions. So this "House Committee," whoever they are can either blow, or get the records from the NSA already.

I know Slashdot is American, which is why nobody posts interesting security-related questions here. If Reddit are getting such questions, then obviously they're not American.

Comment Re:Even more unthinkable - throwing away burnt dev (Score 1) 106

Why would they throw away a burnt hunk of metal? They should have kept the smoldering remains!

As evidence of purchase and the presence of a major fault, yes. Precisely.

When you have a car crash, do you not take photos? Record the names and addresses of witnesses, and the registration numbers of vehicles involved, even if only trivially? The simple failure to do such things is in itself something that an insurance investigator would take as a priori evidence of fraud and use it as justification for a deep investigation of the claim.

Comment Re:someone probably died for this mistake (Score 1) 137

Free advertising.

Which is not considered a thing - neither a good thing nor a bad thing. This whole stupid thing of having choice is just stupid. You're not thinking like an economic planner.

Tourism will see a boost in the coming months thanks to that guy.

This will not happen, and even if it did (it can't) would not be considered a good thing.

How are you going to have a boost in tourism? People would have to get visas and then get trains in (tickets won't be sold, if there are non-freight trains at all), ferries (again, only freight ferries with no provision for passengers), or planes (for which you need a visa).

Have you seen the tourism levels at Area 51? That place gets free advertising coming out of it's ears, and the number of tourists is going through the roof. There might even be one, one of these decades - a huge increase on the past levels.

Disclosure : most of the 2000s, until 2011, I was trying to get work in North Korea. Bloody politicians always getting in the way.

Comment I hate these bullshit religious wars (Score 1) 120

Just get one fucking interface, stop changing things and let us get on with using it instead of changing things every fucking day. Do you have any idea how harmful this is for adoption.

I don't even know the name of the desktop environment that I'm using, and I care less. I just want to not have to re-learn it at some random time in the future, chosen by someone I've never heard of for reasons I don't care about.

Submission + - How will we know a vehicle model is "driverless" (

RockDoctor writes: Some people differ, but having gone through dozens of (simulated) aircraft crashes as part of safety training for work, I hugely prefer to face backwards when travelling. Plane (no choice) train (choice) or automobile (rarely a choice), I prefer to be in a seat that will absorb my momentum from the start of an impact.
The "driverless car" will not be here until all people in the front row of the device face against the direction of travel. Anything less is a partial solution, waiting for a human to take over in a complex situation.
My wife can't travel facing backwards. So I take the risk of being killed by her flying body after I survive the crash. Joy, not.
People will learn to live with it.


Comment Re: Not a nice way to die (Score 1) 429

It's a more complex subject than most people give it credit for. Divers have to pay more attention to the physiology of breathing than the man on the Clapham omnibus, but that is nothing compared to the real complexities of the situation.

With university level chemistry, you'd think that the bond energies and the concentrations of reactants would determine the rates of the reactions in either direction. That they don't indicates that there is some non-equiibrium chemistry going on there - different enzymes catalysing each direction of the equilibrium being a good guess. But enzymes are involved everywhere in biochemistry, so that's still not a very useful answer!

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