Monday, November 30, 2015
(Indeed, yesterday afternoon my daughter pointed out the green colour of the threatening sky, and it was followed by some - thankfully only pea-sized - hail.)
So I was a bit surprised to Google the topic and see that Accuweather in 2007 had an article with the title "Debunked: the Green Sky Hail Myth."
Which is a bit odd, in that it refers to a Scientific American article which only "kind of" debunks it.
Apparently, Americans often take the green tinge as an indication of a tornado - although many also argue the hail connection. The research (by just one person in America) that the article cites sounds distinctly unconvincing - he apparently agrees that green storm clouds do indeed happen and are an indication of a severe storm (well, duh), but seems to dispute its predictive nature for hail (or tornadoes).
Well, this is one case where I reckon life experience counts for more than a paper by one dude in America.
Because I would say that in the vast majority of cases for storms in Brisbane, the distinctive green tinge is an accurate sign that hail is happening (or will happen) somewhere in the storm's path.
I don't know what to make of Dastyari - a Labor Senator on side with the Bald One in the pointless "nanny State" enquiry that is seeking to end the scourge of Australians having to wear bicycle helmets on their way to get a drink in Kings Cross at 2.45am seems to me to have some very suspect priorities. But at least he is showing some sense on climate change, I suppose...
Published Thursday in the journal Science, the study details a tenfold increase in the abundance of single-cell coccolithophores between 1965 and 2010, and a particularly sharp spike since the late 1990s in the population of these pale-shelled floating phytoplankton.
"Something strange is happening here, and it's happening much more quickly than we thought it should," said Anand Gnanadesikan, associate professor in the Morton K. Blaustein Department of Earth and Planetary Sciences at Johns Hopkins and one of the study's five authors.
Gnanadesikan said the Science report certainly is good news for creatures that eat coccolithophores, but it's not clear what those are. "What is worrisome," he said, "is that our result points out how little we know about how complex ecosystems function." The result highlights the possibility of rapid ecosystem change, suggesting that prevalent models of how these systems respond to climate change may be too conservative, he said.
The team's analysis of Continuous Plankton Recorder survey data from the North Atlantic Ocean and North Sea since the mid-1960s suggests rising carbon dioxide in the ocean is causing the coccolithophore population spike, said Sara Rivero-Calle, a Johns Hopkins doctoral student and lead author of the study.Link to the story here.
This is interesting, given that coccolithophores have been the subject of some intensive study to work out whether they are very sensitive to ocean acidification, or not. (The results of lab tests have been contradictory and it's been difficult to work out why.) The concern is (I expect) that at a certain threshold of CO2, this type of plankton suddenly goes into reverse because of the acidification effect.
Sunday, November 29, 2015
Ridley's got another short "what's the problem? AGW won't get dangerous for another century" article which will only convince the ignorant, like Adam Creighton, but he got to run it in Scientific American.
The explanation of why he is a wrong-headed dissembler is given at the link above.
I've never enjoyed Scientific American much, but really, publishing failed banker and coal miner Ridley on climate change?
Saturday, November 28, 2015
* Lenore Taylor has an excellent explanation of how Australian policy got to where it is today. The details of this are hard to keep in memory, so it's really good to see such a clear account.
* And now for the bad: the very bad. Adam Creighton writes with so many errors in his take on climate change, it's hard to know where to begin. Take this paragraph:
But even more problematic, the link between carbon dioxide and global average temperatures is highly uncertain. Sure, it is probably positive, but the degree of the relationship is vague, as sober analysts of the climate change debate will readily point out. Moreover, splicing the effect out from temperature changes that would have happened anyway is next to impossible."Sober analysis" - ha!
This paragraph in particular shows his complete ignorance on the topic:
The other problem with these models is they assume the impact of global warming is unambiguously bad. It might not be. For example, the 44,000 more than expected people who died in the British winter last year — in part because of the cold — might have had a different view.Absolute unadulterated rubbish, and proof he simply does not read the IPCC reports or any other material - where the cross over between any net benefits to net harm has been a matter of hotly contested dipute. (Lukewarmer Richard Tol's error prone work being very significant on this.)
But how surprising is it really, that a small government, anti tax, libertarian inclined economics writer knows stuff all about climate change.
But the basic problem with his argument is the common (and discredited one) - that uncertainty is our friend. It isn't, Adam. Read.
I guess we've all seen or heard of the problem of excess skin on formerly obese people, but the SMH has a remarkable story about it this morning. I didn't realise how lengthy, risky and expensive the surgery to correct it could be. You would think that if more people knew about this they might stop their weight gain before growing or stretching all that excess surface area, but I guess human nature isn't like that.
Friday, November 27, 2015
Here's the abstract, with the important bit highlighted by me:
At a fundamental level, the classical picture of the world is dead, and has been dead now for almost a century. Pinning down exactly which quantum phenomena are responsible for this has proved to be a tricky and controversial question, but a lot of progress has been made in the past few decades. We now have a range of precise statements showing that whatever the ultimate laws of Nature are, they cannot be classical. In this article, we review results on the fundamental phenomena of quantum theory that cannot be understood in classical terms. We proceed by first granting quite a broad notion of classicality, describe a range of quantum phenomena (such as randomness, discreteness, the indistinguishability of states, measurement-uncertainty, measurement-disturbance, complementarity, noncommutativity, interference, the no-cloning theorem, and the collapse of the wave-packet) that do fall under its liberal scope, and then finally describe some aspects of quantum physics that can never admit a classical understanding -- the intrinsically quantum mechanical aspects of Nature. The most famous of these is Bell's theorem, but we also review two more recent results in this area. Firstly, Hardy's theorem shows that even a finite dimensional quantum system must contain an infinite amount of information, and secondly, the Pusey--Barrett--Rudolph theorem shows that the wave-function must be an objective property of an individual quantum system. Besides being of foundational interest, results of this sort now find surprising practical applications in areas such as quantum information science and the simulation of quantum systems.Here's some more detail from within the paper:
At the heart of classical information theory is the idea of a classical bit – the information revealed by a single yes-no question. Our ability to quantify, encode and transform information has revolutionised the world in countless ways (telecommunications, the internet, computers, etc.), and its study has shed light on the foundations of physics. Central to this is the idea that information does not care how we choose to encode it – we can encode information on paper, in electronic pulses or carve it into stone. For almost all of history our encoding of information has been into classical degrees of freedom. However, Nature is quantum-mechanical and, in recent years, we have begun to use quantum degrees of freedom to encode information. A central question therefore arises: does information in quantum mechanics have the same properties as in classical mechanics?
Now, the state of even the simplest quantum system – a qubit – is specified by continuous parameters. This means that it requires an infinite amount of information to specify the state exactly. For example, the amplitude α of |0i in the superposition α|0i + β|1i could encode the decimal expansion of π. Thus, at first glance, it seems that that quantum systems can carry vastly more information than classical systems. However, Holevo [22, 42, 43] showed only a single bit of classical information can ever be extracted from a qubit system via measurement. Further, in spite having a continuous infinity of pure states, quantum computation do not suffer from the the problems that rule out analog classical computers . Powerful theorems on the discretization of errors  tell us that we do not need to correct a continuum of errors, but only particular discrete types. These surprising characteristics present a basic conundrum: how is it that qubits behave as if they are discrete systems when their state space forms a continuum?
As already discussed, in classical statistical mechanics we can consider the allowed macrostates: the set of probability distributions over some state space Λ of microstates. It is easy to see that these distributions also form a continuum – even if there is only a discrete finite set of microstates. As an example, consider the case of DNA bases, which can be in one of 4 microstates A, T, C or G. The macrostate for a single base is therefore a probability distribution p = (pA, pT , pC, pG), obeying Pj pj = 1 and 0 ≤ pj ≤ 1 for all j = A, T, C, G. The set of such distributions therefore forms a solid tetrahedron (a simplex) in 3-dimensional space, and there is a continuum of macrostates (see Figure 7).
The fact that qubits behave in many ways like discrete, finite systems would be easily explained if perhaps there were only a finite number of more fundamental states – like the finite number of DNA bases – and if the continuum of quantum states only represented our uncertainty about which one of them is occupied – like the continuum of DNA macrostates. Surprisingly, in spite of Holevo’s bound and the discretization of errors, this cannot be the case: any future physical
theory that reproduces the physics of finite-dimensional quantum systems must have an infinite number of fundamental states.
The paper then goes onto to explain Hardy's proof of this. It's math-y, and the interested reader (hello?) can go read it in the paper itself.
"Hardy" is Lucien Hardy, who seems to have made quite a name for himself in quantum theory, and is said to have devised a pretty simple proof back in 1992 that quantum physics must be non local.
But the "theorem" referred to about infinite information seems to come from a 2004 paper, which does not seem to be on arXiv.
But there is a 2010 paper by someone (from where, I do not see - another paper just gives a hotmail address for him!) disputing that Hardy is right on this. He argues that "infinite excess baggage also occurs in classical theories".
Well, what to make of this?
Am I wrong, or I am right, in suspecting that the idea of infinite information being necessary in a quantum universe to be pretty significant for a philosophical understanding of the nature of the universe?
It seems that Godel's Incompleteness Theorem gets all the attention from a philosophical implication point of view, but perhaps there is another theorem here that deserves similar thought.
Certainly, for the religious, the idea of infinite information tends to be associated with God, so if Hardy is right, does it suggest more of a Spinoza view of God rather than the Catholic view?
Bit deep for a Friday, hey?
Update: see, when the question is asked at Quora "is there an infinite amount of information in the Universe", most people answer "no".
Thursday, November 26, 2015
As I have noted before, there's a real "whiplash" problem going on in the lead up to Paris, with some apparent experts pointing out things like how much could be achieved in CO2 reductions even with current technology; how coal may have already peaked in China; how batteries could revolutionise the use of clean energy, etc.
On the other hand, you have posts like the one linked above complaining that by pretending that the 2C limit is achievable when it most likely isn't, scientists are giving false optimism to nations, which leads to them not committing to the degree of effort that really would be needed.
On the third hand, surely it has to be realised that the long standing enemies of effective policy towards reducing CO2 (the small government/anti regulation/anti tax conservative/libertarians of America) can seize on discussion that 2C is effectively inachievable to argue that there is no point in seeking to limit CO2, and promote instead a foolhardy "aircondition the planet" strategy (that is, the idea to push economic growth as the priority, including by burning more fossil fuels, because it is only by getting richer that the planet can be airconditioned - or geoengineered - fast enough to survive any temperature rise.)
It is a very tricky business, but I would have thought the appropriate response just has to include the following:
a. likely overshooting of 2C doesn't mean you don't seek to limit it as low as possible above 2C;
b. no one has any clear idea how well geoengineering may work and how it may hurt some countries for the benefit of others. It will only be worth trying once things really are dire, and cannot address ocean acidification in any realistic scenario;
c. don't let pessimism become self fulfilling defeatism. When strong commitment to environmental action is made, the results are often faster and better than expected.
Rare that the creation of a new, useful alloy makes the news. Interesting, though.
I guess we'll be seeing this in Australia soon enough, if it's not already here.
Speaking of exercise in groups (a concept I've always had trouble with), at the local Council swimming pool last weekend I noticed that the free aqua zumba class is terribly popular, but with about 95% of the participants being distinctly unfit looking middle aged women, 3% younger fitter women, and about 2% men. Although it is only the start of summer, and it may be that they will be all svelte beauties by the end of the season, I think the more likely assumption is that it gives them the sensation of being useful exercise, when it really isn't.
Wednesday, November 25, 2015
* one of the "retro" aspects of the film was some very clear product placement, of the kind that I do not recall from the previous Craig outings, but which used to feature prominently in Bond films (particularly in the Roger Moore era, I seem to recall.) The (very unsubtle) Omega watch, for one thing; but I also see (mainly from posters around town, as well a cinema ad before the film) the Sony Experia Z5 smartphone, and a brand of vodka that I can't even recall now.
The Sony and vodka product placement seem particularly pointless to me, given that while the phone might have been on screen several times, I don't think you could ever tell that it was an Experia at all. Let's face it, lots of smart phones look pretty similar, and maybe it is just be my lack of observation skills, but it seems odd that you have to have seen the pre-movie (or TV?) ad to recognise the product on screen.
I think the vodka came out even worse. Or maybe it wasn't even in the movie at all: but the ad before the film indicated it would be. All rather odd.
* I have to admit, the movie did come very close to crossing my "that is such plainly ridiculous science, I cannot forgive it" line that (for example) Goldeneye hurtled over. (I won't repeat the problem in that movie - I mention it about every 12 months here - but it was unforgiveably stupid.) The Spectre issue - Q's laptop which (I think) was meant to incorporate an instantaneous DNA analysing scanner. Now, the movie survives this sequence because it was dealt with so quickly - I'm not 100% sure that this is what it was doing - but even allowing for the impossibility of testing for DNA via some scan, my readers would recall that I posted recently about the incredible unreliability of "touch" DNA analysis, and this was a ring being scanned, about the touchiest thing of all! In other words, even if the laptop could do it, it would be hopelessly unreliable. It is a pity that this survived in the screenplay.
* At a more general level, seriously, why can't studios pay someone sensible (pick me!) to tell them when their plot-crucial sciency-technology bit of ridiculousness is just too ridiculous to stay? You don't need a scientist to do that job: just someone who reads enough science magazines and has a good nose for what is just stupid given current technology, allowing for some extrapolation of what might be possible.
WASHINGTON — President Obama awarded the Presidential Medal of Freedom on Tuesday to an eclectic mix of Americans from the sciences, arts, sports, politics and human
rights, some of them household names and others who he indicated should be.
Among those honored were such iconic figures as Willie Mays, Barbra Streisand, Itzhak Perlman, James Taylor, Gloria and Emilio Estefan, Stephen Sondheim and Steven Spielberg.
There was also the widow of a general who helped other survivors, and a space scientist who was a pioneer in diversity as well as the cosmos.
When a telephone rang during his description of Mr. Spielberg’s many movies, the president joked: “Somebody is calling to see if they can book him for a deal right now. They want to make a pitch.”
And then he made one of his own: “So there’s this really good-looking president,” he started.
In the past 20 years, 90 percent of major disasters were caused by nearly 6,500 recorded floods, storms, heatwaves, droughts and other weather-related events, UN spokesman hasLibertarian Senator responds: "But what about bicycle helmets, not being able to get a drink after 3 am, and the amount of tax I'm paying?"
A new UN-backed report, entitled The Human Cost of Weather Related Disasters, found that since 1995, over 600,000 people died as a result of weather-related disasters and 4.1 billion people were injured, left homeless or in need of emergency assistance, Xinhua quoted UN spokesman Stephane Dujarric as saying on Monay.
The five countries hit by the highest number of disasters were the US, China, India, Philippines and Indonesia, said Dujarric.
The report issued by the UN Office for Disaster Risk Reduction (UNISDR) notes data gaps, saying that only 35 percent of records include information about economic losses.
I guess it's really just click bait, but still.
I'm pretty sure one of the handiest things Nietzsche could advise regarding the conference is "don't catch an STD while in Paris - use a condom!"
Update: here's a contender for an more dubious, apparently serious, contribution from 2012.
Tuesday, November 24, 2015
A 66 year old woman in Queensland was bitten on her hand by a venomous snake for the
"I'm a bit of a pro at this snake business," she said.
"My mum always said it'll be a snake that kills me, so yeah, I'm not really planning on one [a fifth experience], but who knows.
"Just be careful, and wear your glasses when you go outside, that helps."
Ms Thynne said her experience had taught her that if you were bitten by a snake you should "definitely not panic".
"If it's a real deadly looking one, sit under a tree with a cigarette, with a cup of tea and pray, but yeah wrap it up and hope."
As the US media notes, both Trump and Carson can fantasise about Muslims celebrating terrorism in New Jersey, and there is no doubt tens of thousands of their followers will believe it happened.
A Republican Congressman can allege, with no evidence at all beyond what goes on at climate change denying blogs by foolish armchair commentators, that there is a grand conspiracy in NOAA to fraudulently change temperature records. And we know scores of Republican voters will believe it.
Has regard for truth and good will in politics in the US ever been at a lower ebb?
Monday, November 23, 2015
Reading the comments that follow the article, there is some well deserved skepticism expressed of the view that gay men get into this because when they were younger and not "out", they didn't really learn about intimacy in the way most people do. But I have yet to see a comment that uses the word "decadence" in the way someone would have if discussing this years ago.
Whatever happened to politicians and doctors making the rather obvious argument that, if you need or desire a chemical enhancement to make sex more enjoyable than it routinely is while sober and in full control of your facilities, you're putting self indulgent pursuit of physical pleasure on a corrupting and harmful pedestal. It's a wonder that this has to be said at all, but obviously it does.
Maybe time to bring back teaching Aristotle to the schools?
Even less useful is the fact that Ergas apparently has no regrets about posting at Catallaxy, a blog which has become a "free speech" attractant to extreme anti-Muslim sentiment that even Sinclair Davidson has taken to calling "ugly"*. Perhaps Ergas should read the comments threads, where something like this appeared on the weekend:
and then think about the role his mates might just have in encouraging Muslim belief in discrimination.
* He won't delete the comments, though. Or tell his mate Steve Kates that he's a hysterical ratbag when he starts posting about how we are in World War 3 already. He seems to think it best for festering dung in his own back yard to be left on the ground attracting more flies, rather than disposing of it wisely.
Sunday, November 22, 2015
OK. let's get the reservations out of the way. Having re-watched most of Skyfall a couple of weeks ago, I can agree that Spectre is not as good a film. The script of the former was particularly sharp and concise; the movie looked consistently gorgeous; and it sat well with the sort of story arc that the Daniel Craig Bond had been on. In this one, by comparison, the script has its moments, but the villain is far too talky and not as convincing; and the story tries a bit too hard to put some cohesive whole on even pre-Craig elements of Bond. The look of the film is distinctive - the cinematography seems to have dusty sepia everywhere - and while some of it must be a deliberate link with the theme of Bond living in the shadows, I did miss the clear and often glowing look of Skyfall. Oh - and that bland and forgettable theme song. It's funny, but critical reception of a Bond film really does seem to have an awful lot hanging on how memorable that is...
But nonetheless: this is still an impressive and entertaining film that stands up well as part of the incredible re-invigoration of an out-dated character under Craig. (I see he is even a producer of the films now - good luck to him.)
I mean, seriously, who would have thought before he took the role that people would view Bond and take seriously its human drama elements? Sure, I was upset as a 9 year old when Mrs Bond was gunned down immediately after her marriage to that Australian imposter (quite a downer of an ending); but apart from that, there was never any sense of real humanity or loss in any of the Bonds. I also like the way each of these films have fed straight into the next. As with Pirates of the Caribbean, I can imagine watching them all in quick succession on DVD would be rewarding, because the recurring elements will be fresh in the mind and the unfolding, somewhat complicated story make clearer sense.
The things I liked about Spectre in particular: Sam Mendes's return as a director - I guess the lesson is that if you want to take Bond seriously as a character, you use a serious drama director. But the action is also handled so spectacularly well. The opening sequence in Mexico City is just superb, in particular; but all of the locations scrub up well in this movie.
SORT OF SPOILER WARNING: And despite my reservations about the script, I did like the moral seriousness of the ending, and the note of optimism that Bond is ready to "settle down" and find something more fulfilling in life. This really is a big turnaround for the character's arc as played by Craig, and in that sense, it really would be a fitting way for him to depart the series.
But if he does, it will be virtually impossible to believe the series will ever repeat the success of this present era.
And PS: remember, I don't even dismiss Quantum of Solace. Perhaps that tells you a lot about how much I have liked the Craig reign.
Saturday, November 21, 2015
Nature has had a feature up discussing in some detail the promising idea (to many physicists, apparently) that quantum entanglement is actually at the heart of space-time:
All that’s needed, he asserted, is ‘entanglement’: the phenomenon that many physicists believe to be the ultimate in quantum weirdness. Entanglement lets the measurement of one particle instantaneously determine the state of a partner particle, no matter how far away it may be — even on the other side of the Milky Way.The story includes some graphics which help, a little bit, but here is perhaps the key one:
Einstein loathed the idea of entanglement, and famously derided it as “spooky action at a distance”. But it is central to quantum theory. And Van Raamsdonk, drawing on work by like-minded physicists going back more than a decade, argued for the ultimate irony — that, despite Einstein’s objections, entanglement might be the basis of geometry, and thus of Einstein’s geometric theory of gravity. “Space-time,” he says, “is just a geometrical picture of how stuff in the quantum system is entangled.”
Anyhow, the article explains more.
I've also noticed an interesting paper on arXiv by someone from the University of Bristol, of all places. I think it's fair to summarise his proposal as being that quantum non locality derives from a geometry you can get by fiddling with the "time" part of space-time. Here's his introduction:
An elementary discrepancy between quantum theory and relativity is that quantum theory is inherently nonlocal, whereas spacetime has the structure of a manifold, and is thus local by construction. The discrepancy is resolved on the level of information, since the intrinsic randomness in the measurement of a quantum state prevents instantaneous signaling (by the no-communication theorem [10, II.E]). This resolution is satisfactory if information is considered to be fundamental [10, III.C]. However, if one considers geometry to be fundamental, then the discrepancy remains.Of course I don't understand all of that, but its sounds rather interesting.
Here we pursue a possible resolution from the perspective that geometry is fundamental, with the aim that it may shed light on the nature of quantum gravity.1 Just as simultaneity has no universal meaning in special relativity, we propose that a ‘moment of time’ has no universal meaning, and different observers will in general disagree about the ‘duration’ of a single moment of time. In particular, even clocks in the same inertial frame may disagree. The paper is organized as follows. We first propose a new operational definition of time using the identity of indiscernibles: we postulate that time passes if and only if a system undergoes a transformation which is not local and invertible. We then show that this postulate is compatible with the thermodynamic arrow of time in a generic example. Furthermore, the postulate results in a spacetime with positive dimensional events, thus giving rise to Bell nonlocality without requiring retrocausality.
Finally, we examine the ontology of the wavefunction in this framework. In particular, we show that if spacetime events are topologically closed, then the wavefunction is epistemic. Moreover, we find that the preparation assumption of the PBR theorem does not hold using the worldlines of 4-photon entanglement swapping.
And as for gravity and the detection of gravity waves: it's good to see via a post at Sabine H's Backreaction blog that the Parkes Radio Telescope (which I forced my family to visit last Christmas) has been doing valuable work on trying to detect gravity waves via careful pulsar watching.
The sort of sad result, though, is that they haven't found them; which, as Bee says, is "the birth of a new mystery in physics". Not sure is that is "cool" or not....