blueollie

End of the semester academia posts…

This is an article about string theory. The upshot: while string theory has been an unqualified success in explaining many things about physics and cosmology and while it has generated some super interesting, super difficult mathematics, it is not a “theory of everything” and it increasingly looks like it won’t be:

The final results that we found successfully incorporated various established features of particle physics and so were worthy of attention (and, for me, a doctoral dissertation), but were far from providing evidence for string theory. Naturally, our group and many others turned back to the list of allowed shapes to consider other possibilities. But the list was no longer short. Over the months and years, researchers had discovered ever larger collections of shapes that passed mathematical muster, driving the number of candidates into the thousands, millions, billions and then, with insights spearheaded in the mid-1990s by Joe Polchinski, into numbers so large that they’ve never been named.

Against this embarrassment of riches, string theory offered no directive regarding which shape to pick. And as each shape would affect string vibrations in different ways, each would yield different observable consequences. The dream of extracting unique predictions from string theory rapidly faded.

From a public relations standpoint, string theorists had not prepared for this development. Like the Olympic athlete who promises eight gold medals but wins “only” five, theorists had consistently set the bar as high as it could go. That string theory unites general relativity and quantum mechanics is a profound success. That it does so in a framework with the capacity to embrace the known particles and forces makes the success more than theoretically relevant. Seeking to go even further and uniquely explain the detailed properties of the particles and forces is surely a noble goal, but one that lies well beyond the line dividing success from failure.

Nevertheless, critics who had bristled at string theory’s meteoric rise to dominance used the opportunity to trumpet the theory’s demise, blurring researchers’ honest disappointment of not reaching hallowed ground with an unfounded assertion that the approach had crashed. The cacophony grew louder still with a controversial turn articulated most forcefully by one of the founding fathers of string theory, the Stanford University theoretical physicist Leonard Susskind.

On the other end of things:

There is evidence that Bill Cosby didn’t even write his sham thesis.

A principal has been reassigned after a misspelled sign was displayed for more than a week outside a New Jersey public high school.

The message on the sign above the entryway to Paterson’s Public School Number 20 included three mistakes: December was spelled “Dicember,” report as “reepor” and a “1” was placed backwards.

The errors drew the ire of school Paterson Board of Education member Corey Teague, who saw a photo of the misspelled sign on Facebook.

“At first I didn’t believe it,” Teague told CBS New York. “I thought it was Photoshopped or something.”

When Teague found out it was real, he shared the photo on Facebook.

“How can we expect our children to learn how to spell when the administration can’t?” Teague wrote. “We must be held to a higher standard.”

“We can’t assume because it’s an urban district — inner-city — that things like this can be swept over,” he told the CBS affiliate. “If it were a suburban neighborhood, parents would be outraged.”

School officials told NJ.com that the lettering “was placed by a custodian and the sign was near an entrance not normally used by staff.” It was later corrected.

After the gaffe was picked up by several local news outlets, Antoinette Young, the school’s principal, was reassigned as a vice principal at a different school.

The school district did not disclose the reason for her demotion, but according to NorthJersey.com, Young was already under review for unrelated performance issues.

What troubles me is that someone ….even a student…a parent…would have noticed and said something.

And speaking of learning: It is common to get bombarded by the old “different learning styles” canard; I suppose that when you have a calculus class with 35 students in it, you need to accommodate all of their individual “learning styles” (which some might classify as, say, 3-4 distinct ones, or whatever). BUT…there is no evidence for this:

A search of the literature on learning styles reveals thousands of journal articles, books, conference presentations, magazine articles, websites, and so on. The sheer volume of the literature may suggest that the hypothesis at the heart of the theory, that matching instructional style to students’ learning style leads to improved learning, has been well studied, but that would be incorrect. Scholars who have taken inventory of this literature have noted that the vast majority of it is theoretical and descriptive in nature rather than empirical and tends not to appear in peer-reviewed journals. Worse still, very few of the empirical studies were methodologically strong and featured a randomly assigned control group. The few remaining studies, including this most recent one, do not support the learning styles hypothesis.

At best, the instruments which purportedly measure learning styles really just measure studying preferences. What’s more, a growing body of psychological research on metacognition demonstrates that our beliefs about how we process information and how we learn can actually be quite wrong, with people predicting superior performance with instructional methods that ultimately produce inferior results. Therefore objectively-measured improvements in performance, rather than self-reported perceptions of effectiveness, are ideal.

An evidence-based approach is necessary to prevent wasteful spending on ineffective educational interventions. Learning styles theory, despite its continued popularity, has failed to produce sufficient evidence of being a valuable educational tool. By focusing on teaching to students’ strengths this approach misses an important opportunity to encourage students to work on developing their weaknesses as well. The learning styles approach also provides an excuse for poor performance to the detriment of students who will not recognize the need to make changes or seek help.

You can see a rigorous study here.

This rings true for me, but of course, that isn’t evidence either. The study I cited is.

December 20, 2014

Science: mimicry and Maxwell’s Equations

If you have spent time on a campus that has a physics department, you might have seen t-shirts that have this on them:

These equations are called Maxwell’s equations and they describe electromagnetism. Ok, ok, here is integral form:

Here is a brief history of how they came to be; as you may have guessed, the early version was messy and considered incomplete. You are seeing the result of a lot of work and polishing.

Not for a different kind of science: Jerry Coyne’s website has an interesting article about what appears to be mimicry in bird nestlings: they resemble a toxic caterpillar while they are still nestlings. Of course, the science jury is still out as scientists usually require a high standard of proof before they declare something to be “true”.

December 11, 2014

Most of us are pretty anonymous….

I admit it: when I think of “scientists”, I think of the big names that you see on television or on the internet; I think of Nobel Prizes, National Academies, MIT, Berkley and the top laboratories.

But the reality is different. I read a good New York Times article about the scientist who discovered francium and ended up dying from the radiation exposure that she encountered during her work. True, that happened to Marie Curie too. But Marie Curie is famous; the vast majority of scientists who toil for results are not:

Her sacrifice filled a hole in the periodic table, but it did not change cancer medicine, as she had hoped. And after francium, elements were no longer discovered first in nature but were increasingly made artificially. They became curiosities — though still significant to physicists — rather than insights that changed the world. Science moved on, as it does; in 20 years’ time, much of the work that makes headlines now — neuroscience, string theory — may have a totally different meaning from what it does today.

In general, scientists whose risks pay off in the ways they expect are the ones who become the most famous, who get their stories written in romantic and memorable terms. This is particularly true if those expectations are grandiose and the risks they take are tragic. But such people represent a vanishingly small part of those who dedicate their lives to science. “We have this selection bias on when it does work out in an extraordinary way,” Lynette Shaw, a sociologist who studies how we assign value to ideas, objects and people, told me. Perey’s story “gets to this deep question about what’s the value in doing things? Is it the end result? Or is it just because it has inherent worth to pursue them?”

We should celebrate scientists not solely for their accomplishments but also for their courage and the tenacity required to discover anything at all. There are brave people out there working right now. They are brave not because they are killing themselves slowly or leaping from airplanes or catching rare tropical diseases, although scientists have done all those things. They are brave because of the intense emotional risks of trying to do something no one has done before by following your own lead. Radiation is a potent allegory for human life. Everything is always, inevitably falling apart; we are all in arrested decay. Our greatest achievements may become at best footnotes; few people remember us; we can’t know what will eventually come of our work.

December 6, 2014

October 12, 2014

PC’ness, mathematics, quantum mechanics and other stuff….

Shameless fluff: I really like President Obama:

(yes, I know; it is probably edited)

Confession: when I am around a really accomplished mathematician or scientist, well, I end up acting a bit like Chester….. :-)

Quantum Mechanics
Little Boy Boo collapses Leghorn’s “position” wave function:

Of course quantum mechanics uses a lot of mathematics. And mathematics uses things like equations and formulas. But equations and formulas are a relatively recent invention in human history (relative to the time humans have been using writing). Prior to that, an equation such as $4x + 3 = 7$ would have to be written as “a number, when multiplied by 4 and subsequently added to three yields 7″ or something like that. You can see how mathematical progress would have been glacially slow!

Academia: It is nice to see an accomplished liberal academic speaking out against smothering “political correctness. Jerry Coyne talks about some instances that were lampooned by the Wall Street Journal. He then notes:

The WSJ is, of course, a conservative organ, and goes on to decry the “loopiness” of the left wing and the ostracism of conservative professors, as well the tendency of universities to allow “the nuttiest professors to dumb down courses and even whole disciplines into tendentious gibberish.” That’s an exaggeration, but still, it’s disturbing that we see the left attacking, in effect, freedom of speech. If you don’t like Condaleeza Rice (and I sure don’t), that doesn’t mean you should mount such a protest against her that she has to withdraw. Are all speakers to be vetted for signs of cryptic conservatism? Are students that loath to hear views that might disagree with them?

I’m no conservative, but these Commencement Police frighten me, and paint students as self-entitled, fragile beings who can’t countenance dissent—unless it’s their own. At my own commencement at William and Mary in 1971, we had an undistinguished state legislator as speaker—and this after many of us wanted a more leftist person. But we didn’t shout him down, or pressure the university to withdraw his invitation. Instead, we organized a “counter commencement,” held at a different time and place, and our class invited and paid for Charles Evers, the older brother of slain civil rights worker Medgar Evers.

On one point the Journal has it right:

No one could possibly count the compromises of intellectual honesty made on American campuses to reach this point. It is fantastic that the liberal former head of Berkeley should have to sign a Maoist self-criticism to be able to speak at Haverford. Meet America’s Red Guards.

Indeed. The remedy for speech you don’t like and have rational arguments against, is this: more speech—counter speech.

However the “Red Guards” snark is an exaggeration; after all, these people can be stood up to; no one is going to shoot you.

Personal life
Where I was wrong: there was a time when I was part of “a calorie is a calorie” crowd. I was “sort of” right. After all, one cannot get fat if one doesn’t ingest calories; the fat has to come from somewhere.

But though the energy balance is still true, some foods have no available energy for us at all (at least for humans: think “grass”). Some foods are put to work making energy and some foods are more prone to get stored as fat and NOT be immediately used. Hence the new conjecture as to why fat people might be hungry all of the time. Note: I am no longer morbidly obese but I not only cut back how much I eat, I changed what I eat (drastically).

Personal note

Do we sometimes benefit from doing what we don’t want to do? This essay argues “yes”. This is similar to the line in John Denver’s song “Thank God I am a Country Boy”: “fiddle when I can, work when I should”. This essay has an interesting paragraph:

Dr. King taught that every life is marked by dimensions of length, breadth and height. Length refers to self-love, breadth to the community and care of others, and height to the transcendent, to something larger than oneself. Most would agree with Dr. King’s prescription that self-fulfillment requires being able to relate yourself to something higher than the self. Traditionally, that something “higher” was code for God, but whatever the transcendent is, it demands obedience and the willingness to submerge and remold our desires.

Perhaps you relish running marathons. Perhaps you even think of your exercise regimen as a form of self-improvement. But if your “something higher” is, say, justice and equality, those ideals might behoove you to delegate some of the many hours spent pounding the track on tutoring kids at the youth center. Our desires should not be the ultimate arbiters of vocation. Sometimes we should do what we hate, or what most needs doing, and do it as best we can.

He also mentions the situation in which a skilled doctor saved up so much money he could retire and roller blade full time (his true passion) which, while it is what he wanted to do, ended up depriving patients of his life saving skills. I really can’t weigh in as, well, I really don’t have “essential skills”. But I can do things like volunteer (as I do to help new runners build to a healthy life style) and give blood (and I hate that, but will keep doing it…and complaining about doing it).

Note: My body can no longer can stand training for hours on end so the “marathon” paragraph really doesn’t apply to me.

May 23, 2014

About those gravitational waves and ripples in space-time

Physics Professor Mano Singham directs us to this Nature science video.

It is a good video; note that it appears that what is actually being detected is akin to a type of vector calculus curl.

March 17, 2014

Science: skepticism of new findings and explaining it to the public …plus one more Ryan comment

Are we seeing gravitational ripples from the big bang? It is possible.

But announcements of new discoveries or announcements that a long standing model has been modified or even overturned SHOULD be treated with skepticism. That it takes a long time for a new idea to take root in science is NOT a bug but rather a DESIRED feature. Sadly, many, including many in the mainstream media, do not know this. Get a load of this headline from NPR:

Not-So-Objective Scientists Cling To Accepted Wisdom

Overturning scientific dogma is tricky. Reporter Joe Palca tells NPR’s Rachel Martin that one astronomer learned that lesson when he calculated that the universe was younger than colleagues believed.

Note: the paper in question was reviewed for publication and then….published. That is hardly “censorship of new ideas”. Of course, some scientists behave badly but on the whole, existing theory will be modified as new evidence comes in. But proposed new evidence SHOULD be treated with skepticism. That is so difficult for many non-scientists to understand and evidently impossible for NPR to understand.

Speaking of taking science to the public: this 12 minute video from 60 symbols is interesting. A physicist gave a popular lecture and made the comment to the effect “no two electrons in the universe can have the same energy level; hence when one electron changes energy level, all of the rest of the electrons in the universe are affected, hence everything is connected.” Now strictly speaking, the Pauli Exclusion Principle says that no two electrons can have exactly the same quantum state, so if an individual electron changes state, that “affects” the rest of the electrons. This really isn’t controversial.

But of course, some physicists corrected him, and other people went crazy with the woo-woo (common interconnected consciousness, etc.)

Bonus: some politics
Paul Ryan’s comment: no he isn’t racist but his ideas are dated. Still, I don’t think that Mr. Ryan was using the “too lazy to work” canard but rather “the lack of role models…e. g. seeing your parents go to work” situation.

March 17, 2014

Sensationalistic titles of science announcements

Workout notes -3 F outside but sunny; still I ran inside.
First I went on treadmill 1: ran at mostly 0.5 incline and changed speed every 5 minutes. Then at 10:10 mpm I did 10 x (2 minutes 0 elevation, 2 minutes at elevation) going 1-2-3-3-3-3-3-3-3-3 and then 2 minutes to get to 1:01:55 (6 miles).

Switched treadmills then varied the speed to make 2 more miles (21:22).

the plan was to really gun the last 2 miles (at a tempo pace) but the hill repetitions took more out of me than I had anticipated. The intensity: what I call “projected marathon pace”: no I couldn’t actually run a marathon at 10:10 minutes per mile, but this is still a useful training intensity for me, especially for hill repetitions.

Note: I still have to focus; I almost stepped off of the treadmill surface when a nearby woman went into “child” pose (facing away from me, of course).

Sensationalism
Stephen Hawking has some questions about black holes, with regards to the “event horizon”. Of course, it was known long ago that one could have some “Hawking radiation” from these; basically particles can materialize from the quantum vacuum (pair production) and then one of the newly created particles could get sucked into the black hole, leaving the other suddenly unpaired particle as radiation. (yes, this is grossly oversimplified)

But there are unsolved problems, and so Hawking’s new paper deals with these.

But the headlines read: “Hawking says that black holes don’t exist”. Uh…no. He didn’t say that.

Objections to Copernicus: some were valid science objections.

But this is the idea: it took science a long, long time to accept Copernicus’ heliocentric astronomy. True, Galileo saw the phases of Venus and the moons around Jupiter which blew conventional geocentric astronomy out of the water, but there was a “every planet except the earth orbits the sun” model which kept earth fixed.

Why the fixation on keeping the earth fixed? Yes, there were religious objections, but there were scientific objections as well:

1. The earth was known to be massive and scientists at the time knew that it was difficult to move heavy objects. What in the world could move something as massive as the earth?

2. Instruments of the time couldn’t detect stellar parallax. This meant that the stars were a huge distance away. But notice that the stars appear to have a measurable width to them; in fact they should be a “point” of light but that light is smeared out into a disk. At the time, this effect was NOT understood. Hence, a star that was so absurdly far away (as to not show parallax) that appeared to be that wide would have to be absurdly huge, even when compared to our sun.

How do you resolve these two “facts”: great distance and huge size?

Even when heliocentric astronomy became accepted, scientists admitted that there were other problems that cropped up; these problems were not to be resolved until much later.

So, the push-back against Copernican astronomy was NOT entirely religious; scientists of the day had reasonable objections to the theory, and defenders of the then-new theory resorted to….well…appeals to the supernatural and to philosophy to explain away the difficulties.

RANT TO FOLLOW

I admit that I cringed when I saw the title of the article and started to read it. Yes, it was a well written, very intelligent article. And yes, I’ll gladly recommend it to my smarter, more scientifically minded and interested friends. But….there is this…..

“SEE, Science is wrong all of the time!”

(uh, on the whole, science eventually gets it right….you are seeing this on a computer, aren’t you? )

“Hey, they laughed at Einstein”

(uh, as a unknown graduate student, Einstein got his work published in a top flight peer reviewed physics journal; in fact he got 4 of them. Where are your peer reviewed publications? Besides those who came up with the big new ideas are intellectual outliers who completely understood science and the then current theories. You are not one of those, and no, having a good SAT score, passing an undergraduate course or even getting a Ph. D. doesn’t make you that sort of outlier.)

“My ideas are new and radical”

(yes, and most non-mainstream ideas are completely wrong; it is just that we never hear about the vast majority of the wrong ones. What reason have you given for anyone to take the time to listen to you?).

Bottom line: established scientific ideas are sometimes overthrown or superseded or modified, but only rarely and only after a LOT of difficult checking and cross checking by a LOT of smart people ….and they find the new idea promising enough to give in a thorough examination.

January 7, 2014 Posted by | astronomy, physics, science | | 1 Comment

Misconceptions, sensationalism and science

Economics Austerity: does it work? Evidence is scant.

We are adding jobs. All isn’t rosy but things are somewhat better:

Still, unlike some other months that presented decidedly contradictory signals, many of the underlying factors identified by government statisticians at least pointed in the right direction. Hourly earnings, as well as the length of the typical workweek, both increased. The overall labor participation rate, while still low by historical standards, rose two-tenths of a percentage point to 63 percent.

At the same time, jobs were added to a broad range of sectors, rather than restricted to a few, lower-paying areas.

Manufacturing, closely watched because its ups and downs serve as a bellwether of the overall economy, added 27,000 workers. Besides that jump, Mr. Gapen of Barclays said he was also glad to see that the construction sector gained jobs for the third month in a row, indicating that housing continues to rebound.

Physics
Protons, of course, are made up of subatomic particles. It turns out that the total mass of a proton doesn’t change over a superlong period of time. One might ask: “well, why would it?” But this is one of those fundamental questions that should be asked.

Evolution
Lots of times, authors of pop-science articles and books will take a routine fact, loudly proclaim that this fact “kills well known theory/hypothesis/metaphor X” (even if all it does is kill a simplistic caricature of it) and then get blistered by other scientists. Here is such a case; here someone claims that the “Selfish Gene” metaphor is dead. Richard Dawkins says: “Really? I think not.”:

Over at Richard Dawkins’s own site, he’s responded to Dobbs’s misguided critique of the “gene-centered” view of evolution as described in The Selfish Gene. Richard’s piece is called “Adversarial journalism and the selfish gene.“ He’s remarkably polite for a man who’s been trashed in such an unfair (and erroneous) manner, and politely though firmly explains that, yes, he knows about regulatory genes and that, as we know, they’re simply selfish genes that regulate other selfish genes. He compares the toolbox of regulatory genes (a simile the biologist Sean Carroll also uses) to the subroutines of a Macintosh. and then notes:

Does Dobbs, then, really expect me to be surprised to learn from him that:

“This means that we are human, rather than wormlike, flylike, chickenlike, feline, bovine, or excessively simian, less because we carry different genes from those other species than because our cells read differently.”

Does Dobbs really think the existence of genes controlling the expression of other genes is either a surprise to me or remotely discomfiting to the theory of the selfish gene? Genes controlling other genes are exactly the kind of genes I have in mind when I speak of “selfish genes” as the “immortal replicators”, the “units of natural selection”.

Jerry Coyne (a biologist) says more here.

Larry Moran (a biochemist) mostly likes Coyne’s critique, but has some quibbles with it.

The upshot: a biochemist looks, of course, at the molecules and is apt to characterize evolution (a change in the frequency distribution of alleles with time) at the molecular level; the biologists tend to look more at the bodies, organs, etc.

In this case, Moran is more from what I’d call “pluralistic mechanisms for evolution” camp (assigning heavier weight to thinks like random genetic drift, in which neutral mutations (no effect on reproductive success) account for much of the variation) whereas Coyne has been called a neo-Darwinian (Natural Selection is the overwhelming factor, though other factors (such as drift) influence evolution).

This is the type of thing smart accomplished scientists argue about.

Speaking of evolution and biology This is an interesting result in cancer research.

The rough idea is this: cells use something called a “replication fork” when they reproduce. Sometimes this fork breaks. Healthy cells use one mechanism to repair a damaged “replication fork” whereas cancerous cells use a different one.

This might provide insight on how to fight some cancers.

December 8, 2013