OU Summer School (Quantum Mechanics - SMXR358)

Just back from Open University summer school, a week at Sussex University near Brighton doing experiments in quantum mechanics (course SMXR358).

Saturday July 25th

The school proper stared with a lecture on spectroscopy and notation. I guess this was never going to be riveting, but it’s essential for many of the experiments. The problem is that the necessary – and quite complex – theory is covered in the first few chapters of Book 3, which we're not meant to have started yet. So if you were orthodox on the study schedule, the lecture (and, sadly some of the experiments) must seem pretty incomprehensible.

However, there is always someone in the audience smart and well-informed enough to point to a subtle error in the lecturer’s slide pack (no such thing as a 1p state). How the other students must have hated that person!

Afterwards we all retired across the road to the lab common room for the ice-breaker. This started as doleful and frozen as I had anticipated. I wandered around looking for people with group B on their badges, as these people were candidates to be partners tomorrow in the lab, but without much success.

Mark, the course director, then intervened to correctly separate people into their groups for a pub quiz (sample question: how many concrete cows in Milton Keynes?). Each of the four groups A-D was split into two, and of the eight contending teams there were three winners with 7/10. I was ridiculously pleased that one of these groups was mine.

An early breakfast tomorrow as we start at 9 a.m.

Sunday July 26th

Sunday is a working day at summer school. After the 9 a.m. lecture, we assembled in the lab, milling around until the fateful moment when the tutor said “Oh, by the way, we do these experiments in pairs. Perhaps you’d like to team up?”

I think there must have been some covert pairing the previous evening as twosomes quickly began to drift off in search of apparatus. I looked around for anyone still free and quickly cut a deal with a guy who, I found out, works at the Joint European Torus (JET) fusion project in Oxford. Good choice!

In fact our first experiment was a simple measurement of exponential radioactive decay, and to handle the slightly-radioactive Barium¹³⁷ I had to dress up in a pinny (pictured), or as we like to say, in a very scientific and vaguely-white coat.

The author in authentic scientific gear for handling ¹³⁷Barium

When you’ve finished taking measurements, you enter the results into an Excel spreadsheet on one of the many PCs in the lab. Then you push in a memory stick to take the resulting file home with you. I walked across to a PC which someone else had been using – there was a memory stick already pushed, but the owner had wandered off.

How cute! The memory stick had some holiday photos on it which had auto-opened and were brightly displayed on the screen in preview mode. Most of the photos showed tropical beach scenes, but right in the centre there’s this attractive girl, big smile for the camera, lifting her tee-shirt up to her chin. Which I should add was all she was wearing.

So I’m transfixed in front of the screen, unable to avert my eyes. The tutor (yes, it was Stan) wanders by, takes in the scene and asks laconically “Yours?”

I weakly shake my head and flee the scene, followed by a calculating look.

Monday July 27th

OK, it’s summer so it has to rain on campus. Today it’s the longer experiments in the lab. We’re looking at the Zeeman effect, and then measuring the spin of the caesium nucleus. The Zeeman effect equipment - for measuring the fine structure of energy levels in the neon atom in the presence of a magnetic field - is complicated,

Equipment for measuring the Zeeman Effect

as is the spectrum we observe through three devices in series: a Fabry-Perot etalon, followed by a spectrometer and finally a telescope. Here’s the diffraction pattern of the neon spectral lines of interest - seen through the telescope before the magnetic field is turned on to split them.

Neon spectral lines from the Fabry-Perot etalon

In the coffee breaks there was much gloom from staff and some of the better-informed students about the financial future of OU – talk of the end of summer schools as far too expensive, of courses without final exams because too many students weren’t turning up (the OU then loses its Government grant for that student), and of contraction in the number of intellectually-rigorous courses in favour of softer subjects where there is greater popular interest or vocational business sponsorship. Apparently there's to be a formal announcement at the end of the year.

What a depressing prospect. Please Mr Cameron, don’t hit the OU too hard with all those public spending cuts!

Tuesday July 28th

Let me get on to swine flu. On the first day the chief OU person here mentioned the procedure in case anyone came down with it. He was vague about the details: call security on 3333 and ‘measures will be taken’. Right, I’ll be looking out for the guys in biowar suits then. But despite the hundreds of people we have here on campus from across the UK, no-one seems ill. Where has the epidemic gone?

I grabbed one of the OU physics faculty here and asked about progress as regards an OU theoretical physics MSc. As I understand the response, there is a desire to do it but progress is at a very early stage. The most likely route is to base such a course on the existing maths MSc programme and add some extra physics modules which would create a course with a mathematical physics feel.

Erwin Schrodinger’s advice to his beginning graduate students, who asked what they should study.

“Year 1, study maths; year 2, study maths; year 3, come back and ask me again.”

Wednesday July 29th

If you’d have asked me before I came, I’d have said that the typical OU student of quantum mechanics would be young, white, male and an NT. (The NT part is the Myers-Briggs/Keirsey personality type they call Rational, aka an intellectual).

Score 2.5 out of 4. The seventy-odd students here are overwhelmingly white and mostly male. The oldsters are outnumbered by the thirty-somethings but not by much. But the intellectuals are truly in short supply.

It seems to me that a very prevalent personality type here is the early 30-40 year old ISTJ who’s a hands-on engineer in his day-job, and is using this course to brush up on the theory. A guy who’s bright but non-abstract, dogged but not big on the big picture. You might say that’s what you would expect on an experimental course, except that everyone here is doing the mainline QM theory course as well.

What’s the effect? I think a lot of people are finding difficulty in seeing the wood for the trees, which is of course an endemic problem in QM. It does require really good lectures, though, to draw out and emphasise the foundational concepts and put some shape on what’s been learned to-date. So far, I’ve found the two-per-day lectures quite uneven.

Thursday July 30th

At this stage of the school, sexual deprivation is beginning to kick in. The polarization experiment requires graphing sin²(2θ) from 0 to π. Strange to see guys lingering over a piece of mathematics on their computer screens! Perhaps the following is the answer.

Flyer for the disco

Friday July 31st

With all required experiments finished yesterday, it’s home again from my last ever OU summer school. I always dread it at the start, thinking about the hordes of strangers, the endlessly complex experiments, the long hours in the lab. And at the end I predictably feel it wasn’t so bad and the stuff all makes more sense now. Without that level of immersion, the maths MSc next year is going to be that much harder.

See also Summer School Vignettes.
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UPDATE: Dec 14th 2009. Letter this morning - I received a distinction on this course.

Hot spots

I still don't know anyone who has swine flu, despite the media-epidemic.

More worthy of pity ...

I remember all the times I saw old, overweight guys in baggy shorts and bulging tee-shirts shuffling along pavements, at no more than a fast walking pace.

I laughed inside at such unfitness, thought to myself 'who are you trying to kid?' and 'why are you bothering?'. They never looked very happy, always seeming almost terminal.

As I shuffled along the street this morning, carefully pacing myself, I had a curious, holistic identification with those objects of contempt. Yes, I am now indeed one myself.

I console myself: as I get fitter, in careful stages of course, I will soon turn into a lean, mean athletic machine - purposefully advancing as a predator along rural pathways to the amusement of bucolic bunnies and wheezing lorry drivers.

That is, assuming my heart and lungs hold out.

I read "Schrodinger: life and thought" by Walter J. Moore and was impressed by the freshness of Moore's writing and his diligence in unearthing the daily life of Erwin over so many years. What do you make of a guy who spent his life falling in love easily with so many women and then seducing them? A man who in his forties suffers what Moore euphemistically calls a 'Lolita complex'. He ends up with three daughters, none by his wife, who he remains married to until the end. At least the girls got good intellectual genes.

Schrodinger was no friend to the concept of 'bourgeois marriage', and it might be argued in these enlightened times that he was doing nothing wrong. However, his lifelong self-centred and adolescent attitude to relationships led to collateral damage to many (not all) of the woman with whom he involved himself. Typically it was the younger or less well-educated who were left holding the baby, or worse.

His work was mostly blindingly competent in the spirit of mathematical physics. A strong visualiser, he was close in philosophy to Einstein and had little patience with the Bohr-Born interpretation of his wave equation. His culture, approach, techniques and beliefs all seem curiously dated now, but this was a first rate scientific biography.

The other book was Paul McAuley's "The Quiet War" which I finished but with limited enthusiasm. Stereotyped characters, massive sci-tech data dumps, clumsy writing: McAuley surely can do better than this? I commend to you Abigail Nussbaum's excellent review here.

Note: Pauli's Exclusion Principle

Pauli's Exclusion Principle states that no two identical fermions in a given system can ever have the same set of quantum numbers. Here's how it works.

1. Fermions (particles with half-integer spin - 1/2, 3/2, ...) have antisymmetric total wave functions.

2. Consider two bound-state electrons as an example (electrons are spin 1/2 fermions), e.g. in a helium atom.

3. If the spin component is in one of the three symmetric triplet spin-states, then the spatial wave function must be antisymmetric: (ψ_k(x₁)ψ_n(x₂) - ψ_n(x₁)ψ_k(x₂))/√2

where ψ_k and ψ_n are energy eigenfunctions. Clearly n ≠ k here.

4. However, if we tried to put n=k, then the spatial wave function would vanish - this electron mode cannot exist.

5. However, we can have a symmetric spatial wave function:

ψ_n(x₁)ψ_n(x₂)

in which case the spin state vector must be antisymmetric, viz. the singlet state, where the two electrons are each in a superposition of spin-up and spin-down:

([up,down> - [down,up>)/√2.

As a consequence, only these two electrons can occupy the n=1 (1s) shell, differing in their spin orientation which is the only degree of freedom they possess.

6. Note: if n ≠ k then the spatial wavefunction can still be symmetric for a pair of fermions thus:

(ψ_k(x₁)ψ_n(x₂) + ψ_n(x₁)ψ_k(x₂))/√2

In this case the spin state must be the antisymmetric singlet state as above.

Exercise (redux)

I decided to start running again.

Last time I used to run just a couple of miles two or three times a week. I surely felt better for it overall, although my performance soon plateaued. However, I had persistent pains in my hips and knees which never seemed to get any better, so eventually I stopped (February 2006).

Perhaps it was a perception of my general flabbiness, perhaps it was the sight of Lance Armstrong, still - at 37 - battling the alpine slopes. Anyway, I have resolved to take things a little more easy, not push it so much, to care for my joints. And not rush to do too much too soon.

I said to Clare just before I left, about half an hour ago: "If I should die, think only this of me ... it was a big mistake." Anyway, I took it easy and returned unscathed.

We shall see.

Calleva Atrebatum

Today was open day at the Calleva Atrebatum archaeological dig, so we turned up to see what was going on. First of all, what's Calleva Atrebatum, you may ask? Here's what the Wikipedia says:

"Calleva Atrebatum (or Silchester Roman Town) was an Iron Age oppidum and subsequently a town in the Roman province of Britannia, and the civitas capital of the Atrebates tribe. Its ruins are located beneath and to the west of the Church of St Mary the Virgin, which lies just within the town wall and about 0.5 miles (1 km) to the east of the modern village of Silchester in the English county of Hampshire, north of Basingstoke.

"Most Roman towns in Britain continued to exist after the end of the Roman era, and consequently their remains underlay their more recent successors, which are often still major population centres. Calleva is unusual in that, for reasons unknown, it was abandoned shortly after the end of the Roman era. There is a suggestion that the Saxons deliberately avoided Calleva after it was abandoned, preferring to maintain their existing centres at Winchester and Dorchester. There was a gap of perhaps a century before the twin Saxon towns of Basing and Reading were founded on rivers either side of Calleva. As a consequence, Calleva has been subject to relatively benign neglect for most of the last two millennia.

"The site covers a large area of over 100 acres (400,000 sq. metres) within a polygonal earthwork. The earthworks and, for much of the circumference, the ruined walls are still visible. The remains of the amphitheatre, added about AD 70-80 and situated outside the city walls, can also be clearly seen. By contrast, the area inside the walls is now largely farmland with no visible distinguishing features, other than the enclosing earthworks and walls, together with a tiny mediaeval church at the east gate."

Calleva Atrebatum

The current excavation (pictured below) is of the iron age settlement which pre-dates the Romans.

The dig looking east

Making jewelry the iron-age way

After a while the clouds reappeared and the wind got up, so we retreated home. Oh, and I bought the tee-shirt.

Ambiguous Cream Dept.

"Does Germaloid cream work?"

This query is the most common reason why people end up here, so let me answer it.

Yes, Germaloid cream does work in shrinking haemorrhoids provided you use it on a regular basis. If the cream is old, from a tube which has been lying around in your drawer for years, it won't work nearly so well. Keep at it and follow the instructions on the tube.

And now to the story.
_____

Someone with whom I live in close proximity came up to me this afternoon and asked "Is there any difference between Germaloid cream and Germolene?"

"Why" Iasked.

"Well, I found this tube of Germaloid cream in the living room and I've been using it as an antiseptic. Like for cuts, and on my face."

"OK," I reply, "Germaloid cream is for haemorrhoids treatment" - look of shock/horror - "but it's not as bad as you think ...

"Germaloid cream has two active ingredients: one, like in Germolene is a mild anaesthetic; the other is an astringent agent, zinc oxide, which serves to shrivel up the haemorrhoids.

"In fact, if anyone were to suggest you might have the odd stray wrinkle on your face, it might even have helped?"

One non-amused moment later and I believe the tubes have been switched.

(|wood> + |trees>)/sqrt(2)

I think that SM358, the Open University's quantum mechanics course, is solid but perhaps slightly conservative (perhaps cut-down and lean for distance-learning is more accurate).

One of the challenges in teaching and learning QM is that the central organising concepts of the theory can't be comprehended until quite a bit of the machinery has been taken on board. So there's a lot which has to be taken on faith and is therefore mysterious to the student for a while - the wood and the trees problem.

Later in the course, it helps to try to set what has been learned into some kind of structured context, and here I think SM358 falters a bit. Here are some of the things which have mystified me, and my own views on their resolution.

Q. What's so special about the concepts of eigenfunction and eigenvalue?

A. These are foundational concepts in QM but the reason why is initially not very clear. The real explanation is that in QM, unlike classical mechanics, the problem-solving act is in two steps: (i) find the correct wave function or state vector; (ii) apply the boundary conditions of the specific problem to find the probabilities of the possible observable values to be measured. In classical mechanics one simply solves the 'well-known' equations in the presence of the boundary conditions.

Finding the correct wave function often comes down to solving Schrodinger's time-independent equation,

Hψ = Eψ where E is a constant (eigenvalue), for unknown functions ψ.

Solutions to this equation are indeed eigenfunctions - due to the form of the equation - and that's where the utility of the concept comes from.

Q. What is the significance of a quantum mechanical operator?

A. I was puzzled by this for a long time. Were operators in QM something to do with the act of observation (it is said that operators 'represent' observables)? Perhaps an operator corresponds to a piece of apparatus?

No, none of this is true. The operator appears at the earlier step, where the correct wavefunction for the problem has to be determined. The operator is a constituent of the ψ-equation which determines the correct wavefunction (or state-vector or wavepacket) for the problem under consideration (free particle, harmonic oscillator, Coulomb model of the hydrogen atom, ...).

The second stage, working out the probability of different observables being measured, is a calculation of amplitudes using the wavefunction/state-vector already found - it's this stage which is relevant to the apparatus configuration and the measurement process.

Time-independent approximation methods

1. The Variational Method

Purpose: to calculate the ground energy state (e.g. of an atom) when we don't know the correct eigenfunction.

Method: guess the eigenfunction and compute the eigenvalue (= the ground-state energy). If we guess a function with a free parameter, we may adjust this parameter for fine-tuning.

Maths

Let the ground-state have quantum number n=1 and actual eigenfunction/value ψ₁, E₁.

We have: E₁ = <ψ₁ Hψ₁>/<ψ₁ψ₁>

(the denominator to make sure the equation is correctly normalised).

Since we don't know ψ₁, we approximate it by φ₁, giving

E'₁ = <φ₁ Hφ₁>/<φ₁ φ₁>.

If φ contains a variable b, then E'₁ will be a function of b, E'₁(b), and we can differentiate to find the value of b (the 'best' eigenfunction φ(b)) which minimises E'₁. This is our required approximation.

The only practical issue with this method is the labour involved in evaluating

E'₁ = <φ₁ Hφ₁>/<φ₁ φ₁> - multiple integrals,

and the need to guess a 'good' eigenfunction which closely approximates ψ. Note that it's much harder to use this method to compute higher energy states, where n > 1.

2. Perturbation Methods.

Purpose: to calculate the energy state E' (e.g. of an atom) where the Hamiltonian H' is too complex to solve directly. (We do know the relevant eigenfunctions for the related unperturbed Hamiltonian H).

Method: Split the Hamiltonian function H' into a simple unperturbed part H, which we can solve, and a first-order 'perturbation' δH which we can also solve. So

H' = H + δH -- (to first order).

Accuracy may be improved by going to second or higher orders.

Maths

Note that E'_n = <ψ'_n H'ψ'_n> where ψ' is an eigenfunction of H'.

Let E'_n = approx <ψ_n H'ψ_n> where ψ is an eigenfunction of H,

= <ψ_n (H + δH)ψ_n>

= E_n + <ψ_n δHψ_n>.

We can work out E_n which is just the eigenvalue of the unperturbed Hamiltonian H. The expected value <ψ_n δHψ_n> of the first order perturbation δH, the first-order energy 'correction', is also intended to be easy to work out. So we hopefully have a good approximation to E'_n.

Losses for the army in Afghanistan

1. Hitler was of the view that even after the final victory of the Third Reich, it was desirable that low-level warfare should continue on the Eastern Front - to keep the military sharp and prevent it lapsing into a bureaucratized merely peacetime army.

2. When the British army started to take serious losses in Northern Ireland a few years back, recruiters initially tried to minimise talk of operations there. Instead it was skiing in Cyprus, sports in HK. But actually, they found that the danger and excitement of real ops were actually good not just for the quantity, but also quality of new recruits.

3. The probability of dying in Afghanistan is still relatively low. However, the real danger increases the kudos and prestige of every single squaddie out there, as they're increasingly finding when they get back.

My vote? More helicopters + reduce the mission to hunting down the global jihadists and building a proper spy network for after we withdraw from the major military occupation - which should be sooner not later.

It might be argued that the Americans wouldn't tolerate a Taliban government on Pakistan's northern border - what a risk to stability, but the Taliban are really the politico-military wing of the Pashtuns. The non-Taliban Northern Alliance, suitably provisioned by the US, should be able to keep Afghanistan in a suitably chaotic state of civil war for many a decade yet.

Note: since the Afghan National Army is mostly made up of Northern Alliance personnel, this is probably Washington's game plan on a longer timeframe anyway, discounting short-term 'nation-building' rhetoric.

Schrödinger -- Painting

I've been reading "Schrödinger: Life and Thought" by Walter Moore, an excellent biography. Schrödinger was an unusual scientist. Very bright and always top of the class in maths and physics, he was appointed to Einstein's chair in Zurich but, as Moore observes, by age 37 - in 1924 - he had accomplished much that was competent but nothing earth-shattering. If he had died at that point, he would have been a mere footnote in physics history.

The event which propelled him to immortality was his development of his eponymous wave equation over the Christmas of 1925. According to Moore, Schrodinger guessed it based on his deep knowledge of classical physics and more immediately the thesis work of Louis de Broglie. The equation is simple, but its consequences explain much.

Turning his equation upon the leading question of the day, the spectrum of hydrogen, Schrödinger found the energy eigenfunction/eigenvalue calculations easy but didn't know how to solve the radial differential equation until Hermann Weyl told him in early January 1926. Given that Schrödinger was incredibly bright, hard-working and experienced at this stage of his life, Moore finds this surprising.

It is slightly scary to realise just how much maths and physics need to be in your head before you have the tools to make any kind of breakthrough. It must be even harder today, when there is so much more to select from.

Family News

My mother stayed with us from last Friday to yesterday in Andover, giving a chance for Elaine and Chris to paint her house in Bristol on Monday. We took my mother back yesterday and completed the job. Here are some pictures - click on them to make larger.

Painting the upper hall

Beryl Seel coping in the chaos

It's great when it's mostly finished!

'The City and the City' - China Miéville

Inspector Tyador Borlu of the Beszel Extreme Crime Squad find the body of a young woman in a rundown neighbourhood. No-one knows who she is, and the inquiry is going nowhere. Then Borlu gets a tip-off by phone from a mysterious caller in Beszel's parallel city-state Ul Qoma: the investigation has just gone international.

China Miéville's beautiful writing illuminates the dank, decayed, vaguely Slavic Beszel, and the brittle, flashy, nationalist Ul Qoma. Characters on both sides of the divide are richly drawn: real people with real relationships, personalities and career objectives. The novel rapidly turns into an unputdownable page turner. What is really going on?

At the heart of this novel is the weird relationship between Beszel and Ul Qoma. To say any more would be to spoil the impact of the story, but Miéville has come up with the strangest new idea I have encountered for a long while: this is social-science fiction, the personal and political implications of the central concept driving the intricate plot.

Draped around the central, startling idea is a classic detective story, albeit with no explicit sex, no more than a few shootings and a certain amount of low-level police brutality. The dynamics are those of the cities, with Borlu the central character who in the end resolves the mysteries and is thereby propelled finally to a new reality.

I thought Borlu was surprisingly good at coming up with new lines of inquiry on little evidence, ideas which seemed – unfeasibly - to always pan out. And he seems curiously asexual, not even flirting with his feisty assistant Lizbyet Corwi, although she seems quite interested in him. Perhaps the author intends Borlu to be totally mission-focused but it seems to detract from a fully rounded personality.

There are merely quibbles. ‘The City and the City is by far the best, most awe-inspiring book I have read this year and if it also ends up on required reading lists for ethnomethodology courses covering the social construction of reality, I wouldn't be surprised at all.

Spin and Entanglement

In Bristol on Saturday for an OU day school for SM358, Quantum Mechanics.

Susequently working hard since Monday on TMA 03, which is mostly about spin and entanglement. Just has to be checked, scanned and sent now. While I worked away, I was frequently accompanied by torrential rain outside, with thunder booming remotely from Salisbury plain. Not a good week for camping.

Also just finished China Mieville's completely excellent new book "The City and the City" which I'll review shortly.

Otherwise not much else to report: Clare has been refilling the oven's overhead fan filters with activated carbon granules from a set of filters sent to us in error, which don't fit. Since the filter-containers are not meant to be refilled, she has been actively bodging with a screwdriver and funnel, and claims total success. Thankfully nothing will fall out of the sky as a result, right?

The cat is well, has recently caught and killed a vole which it left as a morning gift in the hall, and has resolutely refused to eat any of the kitekat from the six cans I bought over Clare's warnings, on the basis they were cheap. I now discover it only eats felix or whiskas.

Tastewise I must say I couldn't tell the difference.

Our trip to France - with pictures

We drove down to the Pyrenees and camped a while in the mountains. It was cold, there were flies and our air-mattress deflated.

Next we drove north to the Dordogne where we visited chateaux before continuing to the Loire valley where we visited more chateaux and saw Segways for tourists. Finally we got to St. Malo where we spent a pleasant evening before coming home.

This is Clare in the McDonalds at St. Malo just before embarkation back to England.

The full story here or here: PDF, 2.7 MB.

PPP – Product Placement in Photographs

A New Product Idea for Google

Summary

User-submitted photos are image-analyzed into their constituent objects. Generic objects (bottles, cars, watches) are selectively (and somewhat inconspicuously) replaced by product-specific iconic versions (e.g. Coca-cola bottle, Tesla car, Rolex watch). The manufacturer pays Google for this service. The user can opt for the generic versions on payment of a small subscription.

Product Description

Holiday photos are frequently unsatisfactory. The resolution is too low, the digital zoom has removed all detail, there is motion blur – and 2D is so flat. All of this is fixable by algorithms.

STEP 1: User submits a .jpg or similar to Google Images.

STEP 2: Google applies a palette of image-processing algorithms to deblur, identify object edges, resolve ambiguity through contextual knowledge and inference resulting in the creation of a 3D scene description. This probably looks like an XML file.

In many cases the resolution will identify a manufacturer-specific entity, e.g. a jeep. However, in other cases there will just be a generic match such as a bottle, a car, a journal.

The business opportunity is to replace the generic object description by product placement of a distinctive version emblematic of a particular company, which could include adding a logo. Google would charge manufacturers for this service in a variant of their current business model.

STEP 3: The image description is then served back to the user where it can be viewed/rendered via a Google image viewer. This could include viewing at any resolution and 3D rotation.

If the user objects to branded products appearing within their picture (the point would be to make product placement somewhat unobtrusive) then they could avoid advertising by making a payment for the service.

Development

To accurately reconstruct a scene from an image requires contextual knowledge. The Google service should include an interactive function whereby users can correct the results, corrections which could be used to tune the knowledge/inference engine.

Disclaimer

All claims to this idea I freely cede to Google as I’d like to use this service. Ask me also about fixing video, especially from low-resolution camera-phones (and CCTV).

__________

Conceived Wednesday 24th June in the Dordogne.

Dune

My holiday reading was "Dune" by Frank Herbert, which I first read when I was but a teenager.

Re-reading it has been a strange experience: the intelligence, plot complexity and sophisticated back-story are as I recall them from so many years ago. However, I'm a little more experienced in literary analysis these days and assess the quality of writing more critically.

Herbert is good, certainly, but there is a kind of plodding, painting-by-numbers methodicalness especially in the earlier parts. It's very much a boy's coming-of-age fantasy with, I suspect, limited interest for girls. Anyway, Clare didn't seem very gripped when I read her parts of it in camp, and on the ferry.

I am sufficiently engaged, however, to continue the journey I first took so many years ago, and the next three (Dune Messiah, Children of Dune, God Emperor of Dune ... sorry titles, aren't they) are on their way.

While we were en vacances, I erratically engaged with SM358, my OU Quantum Mechanics course, steadily working through the thickets of algebra constituting the time-independent Schrödinger equation of the Coulomb interaction Hydrogen atom.

I'm probably going to say this with more conviction after a later chapter looks at relativistic corrections, but atoms seem very clunky, unmodular things in this universe: not very well designed at all.

On the strength of seeing the extraordinary magic Schrödinger conjured from his equation, I ordered Schrödinger: Life and Thought by Walter J. Moore. Schrödinger was an extraordinary character, whose scientific genius was basically powered by sex with his friends' wives. They don't recommend that in OU courses.