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Comment Re:Thermodynamics (Score 1) 312

The reason why this planet is around 300K is that the surface of the sun only fills a small solid-angle of our sky. Without the 3K background, our planet would heat up until photosynthesis became entropically unviable (by going in reverse as often as not).

When the CMB was 300K then, to prevent water from boiling, a planet would need to be much further from its sun. This would make it very dark; photosynthesis would need to be extremely efficient (which is difficult to engineer, or unlikely to arise biologically).

Comment Re:Wot??? (Score 2) 173

> Everyone knows that trees give us all oxygen so we can breathe

I certainly don't know any such thing. In fact I thought forests were net zero oxygen because when trees die the decay of the tree consumes as much oxygen as the tree produced during its life. Not to mention that of course at night the tree is burning the sugars it made during the day by photosynthesis.

If that were true, why does the global atmospheric CO2 concentration (whilst obviously increasing year after year) have a seasonal oscillation with its phase matched to the growing season of the northern hemisphere (which has an excess of forests rather than ocean)?

Plankton is where there is a possible net oxygen increase because when they go dead they can sink, and when that happens they don't decay.

It might be the production of carbon-rich soil that you're overlooking.

Comment Re:TFAs fantasy world (Score 1) 463

If you buy contraband once, you can immediately identify a large number of other wallets guilty of the same purchase, and you can trace each one's transaction history until they interacted with a legitimate business, and then you just subpoena for shipping addresses.

That is possible if the seller only ever uses one address. You could do it that way if you wanted, but it's not the default way the software works, nor is it how it's meant to be used.

No, it can also apply if the seller has more customers than addresses, or if statistical analysis can recognise that the seller is routinely aggregating that set of wallets together in order to spend the income (say, buying a boat or a trolly of groceries).

Comment Re:TFAs fantasy world (Score 1) 463

Your conclusion betrays a lack of imagination. And also a lack of in-depth knowledge about the system you are criticizing.

Bitcoin is a system of numbered bank accounts with public transaction histories, where the only person who knows your bank account numbers is you, and you can have as many bank accounts as you wish at will. It is not only non-trivial to trace (wallets are a collection of addresses which have no tangible relation between each other, and each transaction reveals partial information about the relation between addresses), it is impossible in most cases, especially if you take certain precautions. You make it impossible by keeping the relation out of the chain.

So, you want to purchase contraband? Just use two different wallets. One wallet that can potentially be traced to your identity, and one that can't be. Is it too hard to do?

And how do you get money into your contraband-wallets, without it being traceable back to you?

Comment Re:TFAs fantasy world (Score 1) 463

Bitcoin is fully anonymous. I think you are confusing authenticated with anonymous.

So not true.

If you buy contraband once, you can immediately identify a large number of other wallets guilty of the same purchase, and you can trace each one's transaction history until they interacted with a legitimate business, and then you just subpoena for shipping addresses.

Bitcoin is a system of numbered bank accounts with public transaction histories. Just because the accounts aren't listed by name doesn't mean it wouldn't be trivial for accountants to trace them back to people. (You can only be anonymous if none of your interactions are with any parties who could ever compromise you, in which case it isn't very useful as an alternative currency.)

Comment Re:its the ecosystem stupid (Score 1) 73

TFA is about northern white rhinos, which are critically endangered by heavy poaching.

So actually for some species, human-caused extinction could be avoided simply by such artificial reproduction techniques. In fact this may be the only way, since there are now so few of these rhinos left that we don't have time to try more experiments to find out how to encourage breeding. (We certainly can't figure it out by observing wild populations, since we've poached those to extinction already.)

Also, if we had a technology to reproduce these animals at a much faster rate than is natural, then poachers (who are using other recent technology to eliminate these animals at a much faster rate than is natural) would cease to be a problem. Posters above have already made the case for preservation by domestication, but in this case (despite all our attempts to eradicate the ridiculous belief that keratin obtains some mysterious power when taken from some phallic icon) clearly the economy already does have a use for these rhinos (and lack of reproductive technology is the main obstacle to farming them, so we would not even need to modify these animals to be more appealing). Thus this technology could easily pay back its own development, even without considering the spinoffs that such iPSC germ cell research would be anticipated to advance human medicine.

But it's still valid for you to emphasise the ecosystem (or would be if you weren't unconstructive). Even if not applicable to these particular animals, habitat encroachment is certainly becoming the prime factor in the incredible rate of current extinctions. This is devastating, since our understanding of DNA is only just advancing to the point that we recognise what a wealth of information is being lost with diminishing biodiversity, it's like burning the library that stores millions of years of engineering insights which can guide biotechnology (for example, most pharmaceuticals even today are discovered, not invented, and their processes of chemical synthesis are similarly not only inspired by biology but often too difficult or more expensive to synthesis except through harvesting natural components), not to mention the encoded historical record (without which our understanding of our past must always have larger gaps), and abstract value (which only grows as are progressively less preoccuppied labouring for bare necessities). Hence the huge importance that we curb the raw growth (rather than development) of the economy, like we are finally only beginning to do in the issue of carbon. And that we halt this planet's human population growth (and it looks like being a long time before we have somewhere else to populate): we educate women (and quit forbidding family-planning tools while we're at it) and do more to eliminate extreme poverty (rather than using the reality that a portion of funds will leak and miss our target as an excuse to not contribute to the target at all). We generally need to adopt a more progressive stance, and quit bashing science, decora. Each extinction may cause a cascade. Who knows what other (perhaps little-known) species may be indirectly dependent on the existence on these rhinos for example. Certainly there will be species-specific parasites that directly depend on the host, which may not be as appealing but still embody potentially-useful knowledge. We only recently realised how organisms unique to a panda's gut are relevant to the development of biofuels.

(didn't really intend anonymous)

Comment Re:Loss of mass (Score 1) 133

That's 14 milligrams, not 13 micrograms. And it may not be negligible if the mass is ejected directionally.

Google "1 kW / c / 250kg". The momentum of 1kW of photons could accelerate the Pioneer by 10^-8 ms^-2, if it were all emitted in one direction.

The anomalous acceleration we want to explain is about an order of magnitude smaller than this figure. Hence, TFA.

Comment Here's the solution to the herd mentality flaw (Score 1) 393

The problem with the /. system is that it's one-size-fits-all. A better system would expose the raw moderation data to the client.

For example, consider a post that is highly informed, reasoned and articulated but expresses some viewpoint which herd sensibilities oppose: So it gets 10 positive and 10 negative mods, and the current system therefore buries it amongst the least significant posts (the system instead elevates a swathe of highly similar posts expressing the majority viewpoint, ultimately just reinforcing one potentially narrow mindset). Unfortunately, the posts I most want to read are the ones that expose me to viewpoints outside of my own. I want to preferentially read the posts that generated a strong-yet-controversial reaction (e.g., ranking posts more according to sum of absoluted mods, rather than the sum of signed mods).

But this is only one alternative ranking scheme. For example, I also want to cancel out the tendency to arbitrarily favour the earliest posts over ones contributed a couple hours later, so I might rank according to rate-of-moderation (calculated using timestamp from the post) instead of accumulated total. Or somebody might develop a Last.FM (librefm) style model, which analyses which other mods tend to agree with the mods who favour your favourite posts, and therefore recommends the posts each of us will personally most enjoy seeing. Or, some people might prefer to build their own trust networks, and preferentially read posts recommended by moderators endorsed by authorities they respect. (For example, on a cutting edge science topic, I'd like to first hear from people who have actually studied related fields, leaving the general sci-fi reference jokes and alternate theory speculations further down the page.)

We have to recognise that /. is already exceptionally good compared to most forums in the world. Try discussing the physics of climate change on physicsforums and you very quickly see the downsides of having some fixed set of "expert" moderators imposed from above (fallibility, autocracy, censorship, etc). The key at /. is automation and democratisation. But it could go further than that, by also democratising the post ranking scheme, and the site administrators only need to facilitate that. (Just like the users themselves perform the labour of eliminating spam from /., so too the users could burden responsibility to evolve superior ranking schemes.)

Comment Re:Telemurder (Score 1) 571

Consider someone who stood inside France and shot an arrow into Germany. That arrow strikes a Kraut and kills them. Did the murder occur in France or in Germany?

If it isn't a crime in France to launch arrows at other people, then maybe Germans should just stand back from the border.

If Ethiopia (reasonably IMHO) declared it a crime to knowingly allow starvation (by hoarding your own surplus), would you consider *your* extradition just?

Comment Re:Different uses require different payscales (Score 1) 189

So private individuals are prohibited from profiting from mash-ups involving large numbers of original works?* I thought we were trying to solve the problem of IP owners (to the detriment of society) vetoing further progress?

*At least, until they set up puppet companies that resell (to the parent company) minor derivatives of the original works individually, for negligible gross price (effectively renegotiating the license away). And even in the best case, the whole idea only benefits creators if the derivative works are not also distributed gratis.

Comment Re:And then? (Score 1) 354

It's true that wiping out mosquitoes could be a cascading ecological catastrophic (consider how many species directly depend on aquatic mosquito larvae at some point in their own life cycle), but this device is an ideal solution because it only blocks mosquitoes from feeding specifically on humans (without affecting those mosquitoes in wild habitats).

Comment Re:10 Years, not Infinity+ years (Score 1) 597

Anything that requires physical manufacturing, quality control, and any kind of regulatory oversight can't hope to go from concept to consumer within less than 2 years.

Which means your industry didn't need IP in the first place, you already have a two year monopoly and a head start for your brand thereafter. (And, if regulatory oversight is really so onerous, just regulate that competitors aren't approved until after you.) I'm more concerned for the useful specialist ebook-author.

Comment Re:not that big a deal (Score 1) 317

Maybe they've clued on to the public sentiment against drug patents? Presenting themselves to be voluntarily charitable seeks to undermine our strongest argument for IP reform, while at the same time they are likely increasing profits (think DVD market segregation, except that the people who still cannot afford to buy the product in their region cannot just download it).

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