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Comment Tidal locking question (Score 1) 267

Low mass stars (and this one is very low mass) are dim, so the habitable zone is very close, so tidal effects of the star on the planet are large*, so under normal circumstances the planet will tidally lock to the star, which is not friendly to life. (Although I wouldn't go so far as to say life is impossible on a tidally locked world.)

If the planet has a large enough moon, it will lock to the moon instead, and avoid the star tidal lock (at least for a while.) So I imagine a planet and moon locked to each other and in close orbit around the star. In this case, what will happen to the planet/moon orbit as it gets perturbed by the stellar tides? Will it remain stable, or has the moon only bought me temporary reprieve from stellar tidal lock?

* Back of envelope tidal calculation:
Luminosity of star L proportional to mass of star M to 4th power (roughly)
Goldilocks orbital radius R proportional to sqrt(L), i.e. R propto M^2
Tidal strength T propto M/R^3 (it is derivative of M/R^2), so T propto M/M^6 = 1/M^5. (It is the 1/R^3 which allows a moon to out-tide the star, despite being very much less massive.)
News says this star is 2000 times fainter than the sun, so about 0.15 solar masses
So tidal effects of star on habitable planets is about 13,000 times greater than tidal effect of sun on earth.
The tidal effect of the sun on the earth are small but noticeable - it causes the difference between spring and neap tides.

Comment This would make it the 5th continent (Score 1) 142

If you are claiming that it isn't coastlines and land areas which make continents, but rather regions of continental rock (whether above sea level or not). If this is so, you can no longer justify counting Africa as separate from Eurasia, or North and South America being separate from each other. So you can pick between the traditional 6 continents by land area, or four or five by crustal rock (Eurasia+Africa, Americas, Antarctica, Australia, and Zealandia if you think it is big enough.)

Incidentally, New Zealand may have been almost entirely submerged 24 to 21 million years ago. http://www.lincolnecology.org....
I don't know if there were any other major Zealandia land masses at the time.

Privacy

GlobalSign Supports Billions of Device Identities In an Effort To Secure the IoT (globalsign.com) 27

Reader broknstrngz writes: GlobalSign, a WebTrust certified CA and identity services provider, has released its high volume managed PKI platform, taking a stab at the current authentication and security weaknesses in the IoT. The new service aims to commodify large scale rapid enrollment and identity management for large federated swarms of devices such as IP cameras, smart home appliances and consumer electronics, core and customer premises network equipment in an attempt to reduce the attack surface exploitable by IoT DDoS botnets such as Mirai.

Strong device identity models are developed in partnership with TPM and hardware cryptographic providers such as Infineon and Intrinsic ID, as well as other Trusted Computing Group members.

Comment Coal to gas conversions? (Score 1) 415

"Many older coal plants have been closing in recent years, thanks to stricter air-pollution rules and cheap natural gas."

How often is it economic to do power station coal to gas conversions? Clearly you need to be near a gas pipeline. Can you just replace coal fired boilers with gas fired boilers, or is it more complicated? If instead you're using gas turbines, there is much less commonality between the old and converted power station, and less reason to convert rather than start with a green field.

Comment Re:No (Score 4, Informative) 328

I think everyone (or nearly everyone) should be taught a minimal amount of coding, not so that they can code, but so that they can appreciate what coding can do (and so they can decide whether they are interested in learning more.)

Here is a parable.
Lecturer was approached by Researcher. Researcher was working with DNA sequences and had received a large computer file with many thousands of DNA sequences. These sequences all had a few characters at the beginning and end which were artefacts of the amplification and sequencing process, and needed to be removed before the sequences could be used by the next stage in the process. This was the second such file Researcher had worked with - the previous time, Researcher had spent about a month editing the file in a text editor to remove the surplus characters. Now they dreaded having to do it again, and hoped Lecturer could provide a better way. Lecturer promptly solved the problem in under a minute with a one line Unix command.

Had Researcher had an idea of what programming can do, they'd have sought this help when they received the first file, and saved a month of extreme drudgery. (Incidentally, this really happened, my current boss was Lecturer.)

I present here (not for the first time) the Woodhams Hierarchy of Epistemological Categories:
1) Stuff that you know
2) Stuff that you know where to find out
3) Stuff that you know that somebody knows
3a) Stuff that you know that nobody knows (a category irrelevant to this discussion but important to scientists.)
4) Stuff you know nothing about
(Compare to the Rumsfeld Epistemological Categories.)

In the parable, 'how to best modify these DNA sequences' was initially in category 4 for Researcher, but would have been category 3 if they'd ever done some simple programming. The difference between category 4 and category 3 cost them a month. The difference between category 3 and category 1 cost them perhaps 20 minutes - instead of writing the one-liner themselves, they had to find somebody who could write it for them. This pattern is typical - when considering shifts in categories (from 4 to 3, from 3 to 2, and from 2 to 1) the benefit of shift 4 to 3 is greatest, and the cost (i.e. acquiring the knowledge) is lowest.

To be a functioning person, you need stuff in category 1, but people usually undervalue categories 2 and 3, which can cover very much more knowledge than you can fit in category 1.

Comment Re:Atl-math (Score 1) 229

Just for reference the important caveat is no logic that can encode basic Peano arithmetic can be consistent and complete. There are plenty of axiomatic systems that are complete and consistent, even complicated mathematical ones (the first order theory of complete ordered fields, a.k.a. the real numbers is complete and consistent). Also a stronger logic can prove the consistency of a subset contained within it. Thus the first order theory of Peano arithmetic can be proved to be consistent via second order logic. Finally you may also want to look up Tarski's indefinitability of truth -- a theorem which gives the results you have here as a corollary, but is simpler: in sufficiently power logical systems you can't even define a truth predicate.

Comment What about nausea? (Score 4, Informative) 115

Many people get motion sickness when in a VR with a moving viewpoint. Having your patient suddenly sit up and vomit would probably not be a good idea during surgery. The simplest solution would probably be to test them on the VR first to see if they are nausea-prone, and choose the surgery VR experience based on that.

Comment Missing hypothesis (Score 3, Interesting) 176

Maybe the noble savage really is "serene, peaceful, in tune with nature, never takes more than he gives", precisely because their ancestors learned such a hard lesson and taught their descendants "don't mess up like we did". (I'm not saying it is so, just that it is consistent with the observation of prehistorical extinctions.)

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