Playing around

A lengthy holiday report

Good for the astronomers

Star wars: Lights set to be dimmed in NSW country towns to allow for space research | DailyTelegraph

I see it's only a proposed plan at the moment, but good to see that the politicians are taking seriously the need to limit light pollution around the Siding Spring Observatory outside Coonabarabran.  (Which is where the photo that graces the top of this blog was taken from.)

Physics mysteries, continued

Tiny black holes could trigger collapse of universe—except that they don't | Science | AAAS

I missed this story from August last year.  How slack of me.

Seems that a paper last year argued that mini black holes in theory could cause the collapse of the universe's vacuum state (thereby ending the universe), but for some reason, they don't.   (And we know that because it should have happened long ago, if it could.)

Interesting...

Easier said than done

Let's Measure Consciousness!   Max Tegmark

Max Tegmark likes big ideas, and here he's suggesting that he's come up with a (possible) way of testing for consciousness.

You ought to follow the link in the article to his paper on arXiv:  even by the standards of what you routinely find there, it's absolutely chock full of maths.

Other things watched

Short movie notes from recent viewings:

Paper Planes:   the Australian kids' movie that was apparently a commercial success is simply ridiculous in its improbable details.   Even my daughter, who is pretty much in the target market, thought it silly.  At least it helps confirm my biases against Australian made films, which currently have a hit rate with me of about 1 out of 100 viewed (and I've probably only seen 35.)

The Cave of the Yellow Dog:  being a film that heavily features yurts, I was probably destined to like it.  And yes, this great looking, naturalistically acted film set on the plains of Mongolia is pleasant and engaging.  Oddly, though, it is very neutral in its depiction of the dog.   Some would say this is a good thing, I suppose (certainly, the people who harp on about Spielberg and sentimentality); but really, I felt the movie could have been better by making at least a bit of effort to make the dog look cuter and more engaged with the girl.

Safety Not Guaranteed: an example of a low budget ($750,000 [!] according to IMDB), independent American film that blows low cost Australian film making out of the water.   Looks great; some charming acting;  good script (although I would have preferred the unpleasant male to be less sweary); and an  intriguing story with a pleasing enough ending.  Confirms my biases against Australian films.  

Deep sea

I've been wondering for a long time if the documentary film about James Cameron's trip to the deepest part of the ocean would ever surface (ha!) on TV, and last night it did, with little fanfare, turn up on SBS.

It was very interesting, even though I was a bit surprised to find that it was completely devoid of tension in the sequences where he drops down, down, down.   It just appeared to be such a mundane, workday thing for him to be doing.

Obviously suffering from not the smallest, tiniest bit of claustrophobia, he also seemed to be always in control of his famous temper, and nary a swear word was to be heard.

In any event, it is well worth watching if you missed it. It's on the SBS on demand service, for now anyway.

An unfortunate typo

My Google Alert for all things Celine Dion must have failed me*, because I see from Time magazine that her older husband has passed away, the report perhaps needing clarification in one respect:

Daniel Dion, the older brother of pop singer Celine Dion, died Saturday, just two days after the death of the entertainer’s husband, Rene Angelil....

The announcement follows the death on Thursday of the 73-year-old Angelil in suburban Las Vegas after a long ballet with throat cancer.

* a joke, dear reader.  And for her fans:  sorry for finding something a bit funny in a sad start to a year for the singer.

A seriously strange star

Comets can't explain weird 'alien megastructure' star after all | New Scientist

I think I have resisted, until now,  posting about the star that might have alien megastructures around it, as I always thought a mundane explanation would be established soon enough.

But with this news, of the star dimming 20% over a century, it is time to me to admit that this is a seriously strange star with something very odd about it:

To confirm the fade was real, Schaefer went to Harvard to look at the
original photographic plates and inspected them by eye for changes, a
skill few astronomers possess these days. “Since no one uses
photographic plates any more, it’s basically a lost art,” says Wright.
“Schaefer is an expert at this stuff.”

Schaefer saw the same century-long dimming in his manual readings,
and calculated that it would require 648,000 comets, each 200 kilometres
wide, to have passed by the star – completely implausible, he says.
“The comet-family idea was reasonably put forth as the best of the
proposals, even while acknowledging that they all were a poor lot,” he
says. “But now we have a refutation of the idea, and indeed, of all
published ideas.”

“This presents some trouble for the comet hypothesis,” says Boyajian.
“We need more data through continuous monitoring to figure out what is
going on.”

What about those alien megastructures? Schafer is unconvinced. “The
alien-megastructure idea runs wrong with my new observations,” he says,
as he thinks even advanced aliens wouldn’t be able to build something
capable of covering a fifth of a star in just a century. What’s more,
such an object should radiate light absorbed from the star as heat, but
the infrared signal from Tabby’s star appears normal, he says.

“I don’t know how the dimming affects the megastructure hypothesis,
except that it would seem to exclude a lot of natural explanations,
including comets,” says Wright. “It could be that there were just more
dimming events in the past, or that astronomers were less lucky in the
past and caught more dimming events in the 1980s than in the 1900s. But
that seems unlikely.”

There’s no doubt KIC 8462852 is behaving strangely, so something must
be responsible, says Schaefer. “Either one of our refutations has some
hidden loophole, or some theorist needs to come up with some other
proposal.”

Free will, top down

I've been pretty busy, and so haven't had that much time to refresh myself on the recent history of "free will" debates in light of the recent post at Backreaction.

I do see, though, that there was recent pretty acrimonious debate between Sam Harris (no free will) and Daniel Dennett (there is free will, in a more limited way than most people might think, but it still exists in a useful and meaningful sense) which really covers much the same ground as Sabine Hossenfelder did at Backreaction.    I haven't had time to read up on all of that.   I would say, though, that atheists seem unusually touchy about their determinism being questioned.  

Of the many things I thought questionable about the Backreaction post, I think I can immediately note the following:

a.  given that physicists know that there is quite a way to go to understanding quantum physics and things like non-locality, possible retro-causation, and the nature and fate of information in the universe (black holes and information loss, for example), it seems pretty presumptuous to think that the state of play as currently understood is enough to write the final word on determinism and free will.  (I know that Hossenfelder disputes this line of argument.)

b.  Sabine writes (my emphasis): 

It doesn’t matter if you start talking about chaos (which is deterministic), top-down causation (which doesn’t exist), or insist that we don’t know how consciousness really works (true but irrelevant).

There's probably a definitional argument to be had here, but when I think of top-down causation I think of the matter of how peculiar it is that ideas that get transmitted between humans affect their decisions and moods.   This seems pretty important when talking about free will and what it means, and I see that there have been recent symposiums devoted to the topic.  (This one sponsored by the Templeton Foundation, who atheists dislike because they think it promotes mystery as a door to maintaining grounds for religion.   I don't like it so much because it also turns out they give awards to crappy libertarian ideas such as opposing a carbon tax.)

Let's just say that I'm not convinced that dismissal of the concept of "top down causation" isn't, again,  premature.

c.  Sabine's criticism of psychological studies that look at the effect of not believing in free will may have some good points, but I still doubt that this is grounds for dismissing all study of the effects of this belief.

That's all, for now.

Swearing at work

Laurentian University professor removed for asking students to agree to profane language - Sudbury - CBC News

The professor in question, Michael Persinger, is (relatively) well known for his work on the "God helmet".

All seems a bit of a university storm in a teacup.

The latest resurrection of political correctness in universities (particularly the extreme cases in the US) always put me in mind of that that very enjoyable 1980's UK series A Very Peculiar Practice.   Seems to me a similar show is ripe for the writing.

So much for ice ages

Greenhouse gas rise will delay next ice age by as much as 100,000 years, scientists say

Ill informed climate change denialists will sometimes try on an argument along the lines of "well, warming is better than an ice age, and as one of those may be just around the corner, we shouldn't worry about pre-empting it by warming the planet now." 

They conveniently forget Hansen's long standing rebuttal that  "..a single chlorofluorocarbon factory would be more than sufficient to overcome any natural tendency toward an ice age. Ice sheets will not descend over North America and Europe as long as we are around to stop them."

And in any event, latest estimates of an ice age were for the next being millennia away, as this article explains.

So, this is what "global warming isn't happening" looks like...

The full press release (as a .pdf) from the BEST  team can be found via this link. 

Tamino does his own graphing of their results here.

An interesting article on boredom

Why boredom is anything but boring : Nature News & Comment

Boring turns out to be neuroscientifically fascinating. 

I'm thinking of sending them a link to some of Club Troppo's posts (particularly, though not exclusively, some of Nicholas' old "great chess games of history" posts) for further research fodder....

(I do seem to be in a bitchy mood today.  Sorry.)

While we are talking about the Right being Wrong...

....I did quite like this recent Krugman column on the matter of the American economic recovery under Obama, and the wrongology of Republican warnings.

In which I am mean to an academic, again

Now, given that I have no inherent interest in AFL football, and have barely understood the saga of the Essendon drug supplements, it is possible that I am reading this wrong.  But as far as I can tell, and even though monty is too polite to say so openly over at his blog, I think it is fair to say that Sinclair Davidson appears to have been about as wrong on that matter as he was on the great stagflation warning of 2011, which I like to bring up every 6 to 12 months.   He also put much weight on the global warming "pause" as a good reason why people should think nothing should be done about AGW.   Given that even lukewarmer Steve MacIntyre (beloved "climate auditor" whose nitpicking role seems to be to convince people that it is really is correct to not see the wood for the trees) now has a post that shows this model to temperature graph:

you have to wonder when he'll admit a misreading of that matter, too.

People who understand more may correct me, at least on the Essendon matter, although truth be told, I'm not that interested. 

Bee on free will (again)

Backreaction: Free will is dead, let’s bury it.

As much as I like Sabine H's blog, I still have trouble getting my head around her arguments about the (lack of) free will.  And she seems to get cranky when people disagree with her.

I should read her post more carefully and come back to explain why I have a problem with it.

Re: David Bowie

I think it fair to say that I sort of get the appeal of David Bowie, but am perhaps just a bit too young to fully get it.  I think his biggest fans are those who started following him from the start, and at that time as a pre-teen I was certainly much more interested in the actual space program than in a sexually ambiguous, psychedelic tinged pop musician's introverted way of looking at it.   (That really was the most annoying thing about the 60's and early 70's:  just at a time the world could be celebrating and extending a stunning  outreaching milestone in the history of humanity, youth culture in the nations that had achieved it went instead down the rabbit hole of sex and druggie self indulgence.)

But sure, he had many good and catchy songs and an eclectic style; and later came to make enough anti-drug comments that he was once quoted by my local parish priest!   I also saw him in self-mocking mode in Zoolander just on Sunday night - the first time I have ever watched it.  Yeah, he seems to have a been a pretty nice guy in his private life (once he cleaned his act up, at least), and it is sad that he's died relatively young.

Probably good news for the germ phobic

You're Probably Not Mostly Microbes - The Atlantic

Seems to have taken a long time for this correction to be made.

Some startling implications for the legal system

Why too much evidence can be a bad thing

I had never heard of this point made in the opening paragraph:

Under ancient Jewish law, if a suspect on trial was unanimously found guilty by all judges, then the suspect was acquitted. This reasoning sounds counterintuitive, but the legislators of the time had noticed that unanimous agreement often indicates the presence of systemic error in the judicial process, even if the exact nature of the error is yet to be discovered. They intuitively reasoned that when something seems too good to be true, most likely a mistake was made.

Then what they actually tested:

The researchers demonstrated the paradox in the case of a modern-day police line-up, in
which witnesses try to identify the suspect out of a line-up of several people. The researchers showed that, as the group of unanimously agreeing witnesses increases, the chance of them being correct decreases until it is no better than a random guess.

In police line-ups, the systemic error may be any kind of bias, such as how the line-up is presented to the witnesses or a personal bias held by the witnesses themselves. Importantly, the researchers showed that even a tiny bit of bias can have a very large impact on the results overall. Specifically, they show that when only 1% of the line-ups
exhibit a bias toward a particular suspect, the probability that the witnesses are correct begins to decrease after only three unanimous identifications. Counterintuitively, if one of the many witnesses were to identify a different suspect, then the probability that the other witnesses were correct would substantially increase.

The mathematical reason for why this happens is found using Bayesian analysis, which can be understood in a simplistic way by looking at a biased coin. If a biased coin is designed to land on heads 55% of the time, then you would be able to tell after recording enough coin tosses that heads comes up more often than tails. The results would not
indicate that the laws of probability for a binary system have changed, but that this particular system has failed. In a similar way, getting a large group of unanimous witnesses is so unlikely, according to the laws of probability, that it's more likely that the system is unreliable.