Thursday, October 29, 2009

House-Hunting in Wales: conclusions

We looked at a variety of properties centred around Rhayader, Builth Wells, Brecon and Llandovery. We saw village new-build properties, mountain cottages accessible only after steep climbs on single-track roads and houses next to rivers or down muddy, tree-shrouded tracks.

We found nothing we remotely liked.

Broadly speaking most of the traditional properties are thirty to forty years old, smaller and darker than we wanted and generally in need of a complete modernising makeover.

The new properties were invariably clumped in little developments offset from existing villages, or were an insert into a gap.

The estate agents all tried to talk the market up but in our view the properties were grotesquely over-priced. One estate agent told us that the local attitude to selling was completed 'relaxed': "they're prepared to wait maybe three or four years around here. Their attitude is that when we get a buyer we'll move - till then they're perfectly happy to stay put."

No wonder they're not very price-sensitive.

Ignoring the market towns which didn't interest us at all, the housing stock is either in villages - fairly tightly clumped, or on the sides of the hills with small gardens. There are houses with land but this is usually for farming purposes.

So in the end we found nothing really which worked for us at any price in central Wales. Perhaps we'll have more luck in the south-west of England.

House-Hunting in Wales: part 3

This morning we awoke in The Lion Hotel, Builth Wells for our last day of house-hunting in Wales. Pictured below is the Northern Ireland-style mural visible from our breakfast table.

Breakfast view from The Lion Hotel, Builth Wells

Our usual trawl of the High Street estate agents garnered a haul of only three possibles, which we filtered in the car to just one, two miles north of Builth Wells.

Approaching past the station and under the railway bridge we drove through a familiar landscape of overgrown tufted grass, abandoned oildrums, rusting equipment, derelict caravans, gravelled and puddled driveways fronting nissen huts of indeterminate function and ... well, you get the picture. Eventually we found the driveway to the oasis of arcadian loveliness as described by the estate agent. I at least was prepared to navigate the pond outside the driver's door and look down the driveway. Clare had meanwhile lost the will to live.

We turned around and came home, a journey illustrated by the pictures below.

The M4 Severn crossing

Welcome to England

Five hundred miles and perhaps twenty properties seen, none of which was remotely suitable. Our new target to search is the area north of Lyme Regis.

Exasperated in Llandovery

Elaine always claims to find the commentaries more amusing than the video. Here was how we reacted when we discovered yesterday that the estate agents in Llandovery, along with most of the town, close up for lunch.

Wednesday, October 28, 2009

House-Hunting in Wales: part 2

We hit the Brecon estate agents soon after 9 a.m. this morning and armed with a sheaf of property details, we were soon driving around main roads and mountain roads. Some of the properties were next to A roads (no thanks). Some of them were in new developments (no!). Some of them were suitably inaccessible, up single track roads with hedges higher than a double-decker bus and no passing places (and even then we failed to locate one such property).

Near Brecon: no garden and another house right behind

We next migrated to Llandovery, where we had been told suitable properties were cheaper. To our surprise, the estate agents all closed for lunch so we bided our time and after collecting another bundle of properties we were soon off again. One property was down a rutted, puddled, muddy track next to a river: we rejected a future life of dampness.

The A40 running through Llandovery

Another was high in the Black Mountains National Park with a view of surpassing loveliness. However, it was old and backed into the sodden hillside – damp-fed moss and fungus coloured the rear walls while the front of the property was too small to support a walled garden, which would have blocked the view.

Great view, shame about the damp cottage

We have ended up in Builth Wells (The Lion Inn) and will tomorrow do a similar exercise in this area before moving on to Hay-on-Wye and home. We are beginning to draw some conclusions about the nature of properties in mid-Wales and I guess we will share our thoughts with you tomorrow or Friday.

Tuesday, October 27, 2009

House-Hunting in Wales: part 1

Having sold our current accommodation (subject to contract), our plan is to buy a house which sits on some high plateau in magnificent isolation, with ample grounds and mountain views and country walks outside our gate.

So far, our search in mid-Wales has proved a mite disappointing.

Rhayader looking south

We arrived in Rhayader at 12.45 today (three and a half hours driving from Andover). After lunch in one of the attractive pubs, we did the two estate agents and after a brief tourist drive to see the reservoirs of the Elan valley (very scenic - don't buy downstream) we took a look at five properties.

To be honest, none of them was particularly inspiring. They were either mini-developments in a nearby village (no 'splendid isolation') or rather undistinguished bungalows fringed by barbed wire in a rural sheep-farming landscape. Somehow it didn't quite capture our dream.

We didn't go for the cottage with this view

Mid-afternoon we abandoned the picturesque, tourist-friendly but tiny Rhayader and drove to Llandrindod Wells, a pleasant Victorian town around 12 miles away which somewhat resembles Georgian Bath. It is however surrounded by valley farms, another house-hunt disappointment. We therefore proceed straight down to Brecon across the mountains, where we saw groups of soldiers being put through their paces. There was a heavy military presence above 2,000 feet.

Clare in this evening's Brecon Chinese restaurant

Brecon has a good feel about it, pleasant shops and restaurants and a cheerful occupied street life. Half-term probably has something to do with it. We ate at the local Chinese which was good, and we're currently ensconced in the George Hotel. Tomorrow we'll be checking whether there are properties for sale nestled in the Brecon Beacons.

The Moralistic Fallacy

I didn't catch much of the Channel 4 show "Race and Intelligence: Science's Last Taboo" last night. The pre-show publicity promised that presenter Rageh Omaar would, in a fair-minded way, demolish the claim that ethnicity was in any way involved in differential mental traits such as personality and intelligence. An example of the moralistic fallacy.

I found the programme profiling Warren Buffet over on BBC-2 much more interesting.

However, it would have been impossible for Rageh Omaar to come to any other conclusion in polite society, so strong is the grip of Human Biodiversity Denial if I may utilize a fashionable term of abuse.

A point related to the moralistic fallacy is the framing of this issue in purely moral terms - "it's impolite and demeaning and racist so it's beyond the pale to even discuss the issue unless you're a member of the extreme right and even then you're soft-peddling these days".

What a close-down! The issue of human biodiversity is a scientific one and an evolutionary one in particular and as usual in science one has to frame hypotheses and gather data. Strange how different the discussion is when one approaches it this way, but it will never get on TV.

Here is what I wrote when Watson was demonised, by the way.

I hope the Royal Mail will not lose the letter I sent yesterday deregistering from VAT, not that filling in the form every three months is such a huge chore. A good year puts me firmly in the category of those small businesses which need to pay VAT. However, this year and I anticipate next year are not good years. My trade, designing public telecommunications networks, depends on capital investment flowing through. And there's not much of that.

Sunday, October 25, 2009

Stourhead in October

We were last at Stourhead in May 2009. We agreed then that there was too much to explore in one day and vowed to return. What better than the first day after the clocks went back to redeem such an intention.

Photographing the Autumn

We started our leisurely day this morning with the sky blue and the air calm and warm. The 40 mile drive to Stourhead was accompanied by gathering cloud cover, however, and we thought we'd probably be the only ones there. Nothing could have been further from the truth, the place was crawling with the species National Trust humanity: stout shoes, corduroy trousers, Gore-Tex anoraks, beautifully-groomed but greying hair. The car park was full of meticulously clean four-by-fours.

Clare after a strenuous walk

We walked to Alfred's Tower, two miles through muddy woodland, mostly uphill. We reached the 150 foot tower at 11.50, ten minutes before it opened. The wait and additional height were too much for Clare, whose blood sugar level had plummeted to new depths. We did an immediate u-turn and made our weary way the two miles back to the main buildings and were revived at The Spread Eagle pub.

The view across the lake

We intend to spend a cosy afternoon reading The Sunday Times and catch the last episode of Emma this evening. Perhaps we were not so out of place at Stourhead as we sometimes imagine.

Saturday, October 24, 2009

UP in 3D

The new local cinema doesn't do 3D so we had to revert to our previous practice of visiting Salisbury (a half hour drive away) to see the 3D version of "Up".

1. The story

The film centres around a grumpy old man named Carl Fredricksen and an overeager boy-scout Wilderness Explorer named Russell who fly to South America in a floating house suspended from helium balloons (Wikipedia). It opens however with a short, showcasing Pixar's capabilities in 3D rendering, which was impressive and amusing.

I also liked the start of the film proper, which reprised Mr Fredricksen's life from a small child, most of it shared with the love of his life, Ellie who finally dies leaving him a widower. But I was always a sucker for sentimentality, of which this film is somewhat overfull.

The main story retains interest although it's overlong and sags in the middle. The characters, who are not entirely stereotypes, achieve their just desserts in the end ... but that's a kid's film for you.

2. 3D

Polarized spectacles are distributed in a cellophane wrapper at the ticket-check point. These fit over ordinary glasses. The 3D effect is quite real and initially impressive. It's not, however, immersive - at least not on a regular-sized cinema screen.

3D added little to the story however, really coming into its own in action and landscape sequences. Seems that film makers have not yet learnt how to use 3D to illuminate subtle, more relationship-centric scenes.

3. Rendering

It's been a long time since I've seen an animation. The people were rendered as caricatures, but the backgrounds were quite impressive. There were scenes where I could have believed that we were seeing real footage of the waterfall in South America, or picket fence suburban America.

There must be actors today who will never die, because they will be digitally rendered in the years to come. No tantrums and a lot less bucks.

Friday, October 23, 2009

A First Course in String Theory

"A First Course in String Theory" by Barton Zwiebach has arrived courtesy of the Amazon courier. This is my OU 'closed season' reading - although flipping through the contents it's pretty daunting: a full year's course for senior undergraduates at MIT.

After sniffing "I thought you were off String Theory" Clare has written a dedication in the cover. It says "Happy Christmas" which I read as faint irony.

Wednesday, October 21, 2009


Now my quantum mechanics course is finished I've had more time to work on fiction. I've moved my scattered short stories to a new blog called "Stories by Nigel Seel". It's also the link to the right of the main blog window here, called "Stories". Reviewing the material as I moved it across I thought some of it wasn't bad. I particularly commend to you "True Romance" which would make a misogynist proud (if they had absolutely no sense of humour).

Tomorrow I will upload there a more substantial piece, c. 5,000 words, which will be sent off to Interzone before Christmas, perhaps along with True Romance and one further long story provisionally titled Urban Warrior which I am still revising.

Tuesday, October 20, 2009

Solicitor Days

Down to Stockbridge this afternoon to meet our solicitors (Brockmans). I guess we're around four weeks from exchange of contracts.

My review of "Superfreakonomics" was posted on the website this morning at 9 a.m., only a few hours after US publication. So it was the very first review. There's a minor achievement for you! The book is mired in pre-publication controversy over the pond as it has been tagged as "climate-denying".

Still, at time of writing everyone else has given it five stars and I gave it three. I must be doing something right.

Monday, October 19, 2009

Whither WiFi hotspots?

I was at the Newbury Hilton this afternoon with a colleague to review a Business Process Transformation pitch. As I arrived first, I powered up my laptop to check out the Internet access. I guess I was hoping and expecting a free WiFi service: no such luck.

The entry browser page was to the BT Openzone portal, and the current price there is £5.88 for 90 minutes (there are other buy-plans where more purchased time costs less per minute).

Naturally I backed out of that and plugged in my Vodafone 3G USB modem instead. The deal here is that £15 buys you 1GB of data - that's 30 hours surfing, 650 emails and dozens of downloads according to the website. I guess that checking my email, sending a Skype message to Clare and looking at a few pages probably cost me much less than a pound.

I think the economics of WiFi hot spots are starting to look very dubious. Perhaps I should say even more dubious than they have in the past.

Sunday, October 18, 2009

Review: Superfreakonomics – Levitt & Dubner

In Chapter 1 we read a prurient but entertaining account of Chicago prostitution. We learn the benefits of having a pimp, the relative cost of different sexual services and why the police go easy on the ladies (this last explanation is unconvincing). Then we move to the high-end ‘escort’ market and consider the case study of “Allie”.

Economic concepts: commodity good, price discrimination, inelastic demand, principal-agent problem. Plus a “how-to” guide on being a successful courtesan.

Chapter 2 is organised around the concepts of data mining. We learn about the financial transaction profiles of Islamic terrorists, the disutility of hospitals and the relative performance of doctors in dealing with different kinds of illness and injuries.

Economic concepts: data analysis.

Chapter 3 is about altruism. The core of this chapter deconstructs a 1964 murder in New York City which was apparently witnessed by many people, none of whom intervened or even reported it to the police. This leads to an appraisal of economics experiments which purportedly showed people to possess an intrinsic core of altruism (leading to Nobel prizes in economics for the researchers). Such an appealing conclusion is debunked as you might expect. The murder story is also debunked.

Economic concepts: limitations of behavioural economics.

Chapter 4 is about perverse incentives and specifically how powerful interest groups succeed in bringing about outcomes which disadvantage society overall. In the sights are doctors and auto makers. It is shown repeatedly that the hero who correctly points out that the emperor has no clothes is subsequently uniformly reviled by said interest groups

Chapter 5 is the part about global warming. Or is it cooling? Or is it something which just happens anyway? A long piece centred around Nathan Myhrvold’s company Intellectual Ventures shows that assuming global warming is actually the problem fashionable opinion claims, there exist a number of technological solutions which for a modest amount of cash would deal with it. Alas, such ideas are anathema to Green lobbies.

In the epilogue, we learn that economic concepts of monetary value and exchange can also be taught (and internalised by) capuchin monkeys. I was not entirely clear why we were being told this apart from the monkey prostitution link back to Chapter 1.

I am torn two ways about this book. In its favour it makes intelligent points about a number of topical issues, it correctly undermines various shibboleths of political correctness, and it’s compulsively readable – I was able to finish the 216 pages in a day.

On the other hand, the sycophantic writing style is gratingly folksy-humorous. Subtle flattery throughout confirms the authors and reader as equal partners, intellectually superior to the idiots the book so delights in debunking. The book is somehow less than the sum of its parts.

So if you are looking for an upmarket Reader’s Digest type book which will confirm you are an important mover and shaker, that you are fashionably dismissive of political correctness to an acceptable degree, and that won’t force you to engage with any difficult concepts, I guess this book is for you. Otherwise get it from the library or read the Sunday Times serialisation.

Friday, October 16, 2009

Our house sale - an offer accepted

Yes, at ten to six this evening Clare got a phone call from the estate agent.

An offer of £345,000 (our guide price is £350k).

Clare accepted.

So we hope to be out of here by Christmas.

Did all that mathematical modelling help? I'd like to think so!

SM358 Exam - not so bad

For a long time I believed it was a joke. An Open University exam to be held at Southampton football ground? Really?

It took me 50 minutes to drive down to the stadium and find my way to the first floor suite where the exam was to be held. To my surprise the room was enormous, with space for 16 rows of miniature writing desks leading back to the picture window. All this was initially hidden by screens so that when you walked in you saw red carpeting with upholstered chairs laid out like a departure lounge and maybe fifty slumped people each looking at the floor, as if informed of a death in the family.

I joined them.

We were wheeled to our places at 2.15 p.m. to unpack our pens and instruments and fill in the various slips. At 2.30 I picked up the SM358 question paper and began to review this year's questions on quantum mechanics. I thought it was a pretty fair paper, with little tricksiness.

It's amazing how fast three hours can go when you have a very great deal to do. And as far as I could ascertain, no-one put their hand up and asked to go to the toilet, no doubt a source of vast concern before the three hour exam got underway.

Results due on December 18th.

Update December 16th: I'm pleased to say I received a distinction.

Thursday, October 15, 2009

The secretary problem applied to selling your house

This problem goes under various names: the secretary problem, the sultan's dowry problem, the 'choose a fiancée' problem, the beauty contest problem.

In the beauty contest variant, you are the judge. You are presented with the contestants one-by-one. After evaluating each contestant, you must either declare that contestant to be the winner, at which point the contest ends; or disqualify the current contestant from any further consideration and move on to the next girl.

The question is, which choosing strategy makes it most likely you will choose the best, most beautiful candidate?

Clearly, if you choose the first girl you see, you are rejecting all the rest without seeing them: hardly smart.

On the other hand, if you just keep on rejecting until you come to the last one, you're stuck with her. How likely is it that she's going to be the very best of the lot?

Clearly a better plan is to keep looking (and rejecting) for a while to get a sense of the general level of beauty, and then choose the next contestant you see who is more beautiful than all the ones you've previously rejected - hopefully before you run out of candidates!

If there are n girls in the competition, it turns out that the best strategy is to consider and reject the first 37% of n (exact figure is n/e) and then choose the next candidate who is the best so far.

This leads you to choose the girl who is actually the most beautiful 37% of the time (exact figure 1/e). Not stupendous odds, but reasonable under the constraints.

The reason for mentioning this is that selling a house can look like a version of this problem too. The viewers come one by one and make an offer (a dowry) to you.

If they're not interested, their value to you is zero, they're not beautiful at all.

Or they make make an offer which doesn't impress, they're not all that beautiful.

Each of these viewers is telling you something about the overall market - the space of possible offers for your house. So when should you accept an offer, realising that it's the best you're likely to get?

One of the issues with the secretary problem, in all its variants, is that you need to know the total number of applicants in advance. This translates to the total number of viewers you are prepared to tolerate.

Noting we are currently seeing an average of 2 viewers per week, for the sake of argument I'm going to take three possible viewing totals: 16, 24 and 32, corresponding to the house being on the market for two months, three months and four months.

If n = 16, you should see and reject bids from 37% of 16 = 6 viewers, and then accept a higher bid once you get it from a subsequent viewer.

If n = 24, you should reject bids from the first 9.

If n = 32 you should reject bids from the first 12.

The model therefore advises that we should see and 'reject' a few more - we have so far seen and 'rejected' seven viewers (six of whom did not make formal offers).

Of course, this also applies to buying a house where the message is: don't make an offer too early.

Wednesday, October 14, 2009

House sale: four weeks + Adrian returns

Four weeks into house selling and we have received one offer from seven distinct viewings (which we turned down). We have had three repeat visits making ten viewing events in all. The market is still crawling around on the bottom without too activity. We're hanging in there and thankful that we have no pressing deadline to sell.

Adrian arrived back this morning after a thirty hour flight from Christchurch, New Zealand via Singapore. In about a month's time he'll be off to Canada (Sun Peaks) for the winter season as ski & snowboarding instructor. He's looking remarkably fit and awake as I write this.

I've pretty much completed my revision for the SM358 QM exam this Friday. Horrible to relate, I'm still finding pretty obvious things which puzzled me - example: energy levels of the helium atom ignoring electron-electron repulsion. Easy once you check back in the book.

Evening Sky

View yesterday evening in what had been a tee-shirt and jeans day.

Monday, October 12, 2009

Quantum Theory and Telecom Networks

I originally speculated on whether there might be a "deep theory of telecoms". Roy Simpson wrote to me as follows.

Ok, well here are some comments on that 2008 post based on the original question.

First there is no reference to the ideas of new physics directly applied to telecoms which was my original point, e.g. nothing on quantum routers (even quantum computers).

More generally the problem with the post is that because the axiomatisation mentioned by A. Wheen never happened in the book we don't actually know what you count as "Telecoms Mathematics" i.e. what is in scope and what is out of scope.

We have several axes to consider and the impression I have from that post is the following:

1. Operations vs. development axis

On this axis I guess that you are referring to the mathematics as used in current telecoms operations (which I agree is relatively graph- and statistics-based but not a huge conceptual leap anywhere), rather than what might be required in the development process of new types of structures, connections, equipment and technology.

2. Telecoms as existing system vs software development

Basically further depth on the point above. Two thirds of a telecoms system is software - an area in which reliability, real-time behaviour modelling, enhancement is underdeveloped and requires mathematical models (maybe) of all kinds.

3. Current vs. new axis

Again are we refering to what is currently done to model and develop systems or what could/should be done to make it all cheaper/better/smarter. Remember that some have advocated e.g. learning systems to help the telecoms network do its network management better.

4. Maths vs. Physics axis

In true STL systems fashion are we referring to just a maths solution or also a physics based solution? Any physics (e.g. the network timings using relativistic satellites) brings in its own maths and maybe its own new maths challenges.

And lets not forget the NP-completeness corner. So many published network algorithms seem to falter "in general" as the underlying problem is NP-complete. Again any solution here might bring in unknown new maths/logic.


Well, several of the problems you note above are common to any large-scale software system. To concern oneself with telecoms per se, we need to formalise what we mean by a telecoms system in some useful way.

I guess my intuitions tell me that a telecoms system is a network structure with endpoint nodes and interior nodes such that messages can be routed node-to-node between arbitrary endpoints. I guess everybody can have their own definition of course.

As I've defined it, the analysis of telecoms systems is a subdivision of classical graph-theory - especially in the design of routing protocols as you might expect. Small networks never pose any problems, so requirements for new technologies could be expected when dealing with scaling problems.

Telecom architects and designers are, as you might expect, highly-sensitised to scalability issues just because they are so important - the IETF for example normally has scalability as a major protocol/architecture design constraint, see any RFC.

As to whether quantum theory could be in any way relevant, it seems to me that today we see the relevance in three forms.

a. Classical devices (e.g. integrated circuits) which internally rely upon explicitly quantum phenomena to work at all. These are found in all telecom equipment

b. Quantum network functionality - most likely involving entanglement - which explicitly might add novel functionality to improve telecom network operation. There might I suppose be applications in routing, considered as a distributed form of quantum computing, although it seems a long way off. Ditto for quantum teleportation. As you suggest, this will be in SF stories before it gets to research papers and then into 22nd century networks!

c. End-to-end issues, most notably quantum encryption and key distribution, where it's a constraint upon the network that the end-to-end requirement (typically not to collapse entanglement) should be met. Here we obviously have things happening right now.

Selling our house: the first offer

Today we received the first offer for our house, one for £325,000 which we rejected.

We bought our house six years ago in October 2003 for £300,000. Over recent years the Government has operated an annualised inflation target of 2.5%, around which the actual rate has fluctuated.

Given a nominal 2.5% inflation rate, what is the equivalent today of £300,000 six years ago?

Answer: £300,000 times 1.0256 = £348,000.

Even if we achieve our target price of £350,000 we will have made essentially a zero capital gain - in fact a significant loss once you take transaction charges into account.

Who says that property is a good investment?

Amazon Kindle? Not yet!

The Sunday Times (ingear) recommended waiting a while until the web access of the US version is added and more UK-centric services arrive. But even then I fear I am not tempted.

1. The cost: at £175 you can buy a lot of old-fashioned books.

2. The Amazon Kindle ebook format is proprietary, so I guess you can't easily transfer ebooks to any other device.

3. At the moment I can just hand a book over to someone else to read. Now I've got to hand over the Kindle too and Clare would probably drop it in the bath (her point, not mine).

The Kindle's advantages: a whole library in a slim package and instant loading of a new title over its wireless connection, aren't sufficient to offset its disadvantages at the point of use.

What could make a difference? A really good text-to-speech function would be a start - we all like being read to. I heard they had to disable this function because of copyright mutterings from the 'audio book community'. Great.

Friday, October 09, 2009

Shadow strikes again

Found strewn in our garden this morning as, in my ceaseless attempts to improve the English climate, I went to collect coal for the fire.

A headless corpse

Scattered body parts

What are we do to with him?

Update 1: (2.45 p.m.). Clare has now buried the rabbit.

Update 2: we have two more viewers for our house tomorrow.

Thursday, October 08, 2009

Open University: SM358 The Quantum World

This third level OU physics course comes in three books.

Book 1: wave mechanics introduces Schrödinger’s equation and takes the reader through the standard models of particles in infinite and finite square wells, simple harmonic oscillators, and free particle wave packets. The book concludes with a first look at scattering and tunnelling, along with probability currents.

Book 2: quantum mechanics and its interpretation starts with Dirac notation and the vector space model of quantum states. The next few chapters introduce the angular momentum operators and spin followed by many-particle systems and indistinguishability, including the Pauli exclusion principle.

The final part of the book moves into the modern areas of quantum entanglement and the EPR ‘paradox, and briefly introduces quantum cryptography, quantum teleportation and a very brief mention of quantum computing.

Book 3: quantum mechanics of matter opens with a thorough analysis of the hydrogen atom. We start with spherical harmonics, then look at the radial equation (for the radial part of the wave function in spherical coordinates). This allows us to account for the spectroscopic data for hydrogen in a first approximation.

In chapter 3 we detour to study perturbation methods for solving more complex versions of the Schrödinger equation by approximation and then apply these to helium as well as developing a more sophisticated analysis of hydrogen involving the fine and hyperfine structure. We now have the tools to analyse more complex atoms with many electrons – we learn about electron shells and the Periodic Table.

Next come diatomic molecules and then an overview of the quantum treatment of bulk solids. Now we begin to understand the real differences between insulators, semiconductors and full conductors. In the final chapter we look at the interaction between atoms and electromagnetic radiation, treating the former quantum mechanically and the latter classically. And that’s it.

Some summary thoughts. SM358 is a very thorough, somewhat conservative and rather practical first course. It deliberately doesn’t get involved in populist worries about ‘the meaning of quantum mechanics’: the focus is very much on learning concepts and techniques. This is wholly to be applauded.

The concepts are of course very alien and the course material really needs to be read at least twice. The first time to ‘load the concepts’ - hard work because of their novelty. The second time to knit them together into a holistic totality. Revision for the exam is very important for this final consolidation and sufficient time needs to be budgeted.

Overall, the course is somewhat similar to the material covered in “An Introduction to Quantum Physics” by A. P. French and E. F. Taylor. I found the extra depth in this textbook sometimes helpful in illuminating concepts.

What is barely hinted at is the elevated ladder of which this course is merely the first rung. The next step would be a graduate-level 'proper' Hilbert space development of non-relativistic quantum mechanics. This would be complemented by Quantum Field Theory, which as the name suggests quantizes the classical fields and unifies quantum mechanics with special relativity to give us the Standard Model. And then there is the search for grand unification, combining the four forces of nature into one coherent framework. This takes us to quantum theories of gravity, most notably String Theory.

To climb this ladder would probably take an ambitious young physicist most of their twenties.

Country Scenes

The countryside around Penton Mewsey, bathed in afternoon Autumnal sunlight.

Sheep opposite The White Hart, Penton Mewsey

The Cricket Pavilion, Penton Mewsey

Clare and Nigel in The White Hart

A view towards Foxcotte

The author in the pub

Wednesday, October 07, 2009

Winchester University

I'm typing this from the student coffee lounge at Winchester University - opposite the prison and next to the hospital - there's food for thought!

As I write, Clare is attending her first OU AA100 tutorial in the main building somewhere, and I'm exploring remote Internet access. Meanwhile the rain is pouring down on the other side of the picture window, as it has been doing all day. We got soaked on our arrival after parking: we didn't know where any of the rooms were and wandered erratically for hundreds of yards between buildings in the downpour.

Returning damp and dripping to the coffee lounge, I initially tried to log onto an unsecured WiFi network here, but it asked for a user-id and password: my skills and inclination don't run to the couple of hours I have here trying to crack it. Instead I pulled out my Vodafone dongle and was rapidly connected to the local 3G network at around 280 kbps. For network traffic like this, it's indistinguishable from the 5 Mbps I'm getting in my home office.

Update: home now. Great relief I wasn't clamped for parking in the reserved staff area!

Tuesday, October 06, 2009

Pandorum - 108 lost minutes

So there's 108 minutes of my life I won't get back. Those minutes were spent in the vast interstices of the interstellar spacecraft Elysium, carrying thousands of deep-sleep colonists to a new planet. As is traditional in these ponderous, derivative, dystopian SF movies, the ship resembles nothing more than a spaceborn version of a vast council high-rise on a gang-ridden run-down estate. All is gloom, narrow garbage-strewn tunnels and intermittent power cuts. Around every corner and behind every dripping grating lurk crazed mutant zombies who need their fix of human flesh. There are lots of fights.

After 50 minutes of a mindless quest to 'find and reboot the reactor' interspersed with loud-but-non-frightening mutant-action scenes I whispered to Clare "Let's get out of this stupidity."

To my amazement she was dismissive, transfixed - "No, I want to see what happens!"

Yeah, right.

We all escaped the spacecraft at minute 107. We duly went off to the next-door Asda store to buy some cat-food. I had no such culinary expectations for the 1,213 lifepods deposited with no supplies on an utterly bare target planet, the last surviving humans in the universe.

Clare's verdict: "I wouldn't recommend it but ... it was OK and I've seen worse."

Monday, October 05, 2009

No common sense whatsoever

An embarrassing read for me as it has always been claimed that I lack common sense.

Olber's Paradox

I was walking in the woods with Clare yesterday afternoon (pictured) when apropos nothing at all I mentioned the marvel of the night sky.

If you look up on a clear night you can see the stars of course, but most of the sky is black. From this a profound conclusion emerges.

"If the universe," I said, "was infinite in space and time, then in every direction you looked in the sky, your line of sight would intersect with the surface of a star. So the night sky would be uniformly bright, not dark at all. This is called Olber's Paradox."

She thought for a moment. "Why exactly? The stars that are really far far away are too faint to see. The darkness of the night sky actually proves nothing."

Good point. There are lots of stars out there fainter than magnitude 6 which we don't see with the naked eye at all. Collapse of my argument and I resolved to check when I got home.

According to the Wikipedia article, the explanation is that in a uniform infinite universe, as you increase the distance from your eye by a given amount, the luminance from each star does indeed go down, but the number of stars goes correspondingly up. It sounds convincing in a hand-wavy way, but can we make this more precise?

Suppose we take a particular line of sight - a one dimensional line from your eye to a spot in the infinite sky and assume the stars are equally spaced along this line.

So the first star is at a distance of one "unit" (which might be a thousand light years), the next strung along this eye-line is at a distance of two thousand light years, the next three thousand ... and so on. Suppose each star send one unit of brightness to your eyes. Then the inverse-square law total brightness from this infinite bead of stars will be:

Total brightness = 1 + (1/4) + (1/9) + ... + (1/n2) + ...

OK. So what's the sum of this infinite series? I sat down with a pen and paper and tried to work it out: it's surprisingly hard. I did some approximations and guessed it was just over one and a half.

Wikipedia tells us that this was a legendary problem in early-modern times - the Basel problem - solved by the famous Euler in 1735. The answer is π2/6 = 1.65 approx.

But this doesn't really solve the problem. If the star was pretty faint in the first place, then all of its further-away clones only make it 65% brighter. You still wouldn't see it.

What we're not capturing is the increase in the number of stars in a given solid angle as we project the eyeline farther and farther away. For a given patch of sky, the area at a distance r from your eye is proportional to r2 - think of the area of a sphere, 4πr2. So at a distance r we have to consider not one star, but r2 stars. The true brightness you would see is:

Total brightness = 1 + 4(1/4) + 9(1/9) + ... + n2(1/n2) + ...

= 1 + 1 + 1 + ...

So the correct statement of Olber's paradox in an infinitely-old, infinitely-sized universe is that the night sky is infinitely bright.

I think we would have noticed.

Darkness tells us the universe had a definite beginning some while back, or that it's got a finite size, or both. Quite a big conclusion from darkness at night.

Saturday, October 03, 2009

The Vyne, north of Basingstoke

On an overcast, blustery Saturday we revisited The Vyne, an Elizabethan country house just north of Basingstoke. Three woodland walks beckoned and eschewing green and yellow we took the brown route, at 2.3 miles the longest.

On our circular walk we met coming the other way a family comprising a large, 'pub landlord' kinda guy with a couple of equal-sized dogs, followed by his thin 'partner' followed by two small kids, the girl being called Paige. Actually we met them twice and they were friendlier the second time round.

We also encountered a number of conker shells, with surprisingly sharp spikes.

Our tranquilly was somewhat spoiled by helicopters hovering invisibly above the dense tree cover, which I speculated were hunting for the family already described.

The Lake

The Vyne

The Walled Garden - Clare is quite envious!


This "Bruce Willis sci-fi actioner vehicle" was not as bad as I had feared.

We already have surrogates - sort of. Guys in recliners in Nevada flying Predator RPVs over Afghanistan. In this film pretty much everyone is at home in a recliner, wired-up and 'piloting' their humanoid surrogate at work and at play.

What's not to like? No more fear of mugging or accident (your surrogate may get it, but you're safe at home). Your incredibly-lifelike surrogate is more handsome/beautiful than you, stronger and younger. So folks, this is definitely going to happen, once they get the wireless broadband speeded up a bit, and figure out how to build them.

As an exercise in futurology this film was full of ideas. The military will want surrogates for close-quarters combat: we saw that. The sex industry will want them for enhanced appeal to clients and control of infection: we didn't see that!

But is there a danger we will replace the spontaneity and intimacy of human interaction with one-step-removed machine-mediated distance? Of course! How else could we get a plot?

So the founder of surrogacy has had second thoughts and is trying to get them all closed down, while the surrogate-manufacturing global corporation wants to close him down for their own protection. Off we go.

Surrogacy, in this context, is such a big idea that there is potential for a number of films to explore the implications. This one was content to aim no higher than B-movie status, with Willis seeming to sleepwalk through his part. It was kinda fun and a little bit thought-provoking, but no more.

Thursday, October 01, 2009

Passing The Exam

Dr Gamal Khaled, religious instructor, sits back on his heels as he waits for his student Miss Sahar Al-Amir. He teaches in the only Western-syllabus university in the country, built with funding from the Americans, bloated with eagerness to share that great gift to the world, their American culture.

Gamal is pious but not stupid. Unlike the fundamentalist teachers of the Madrassas which dot the capital, he knows that it’s not enough to learn the sacred texts by heart and eke out doctrine-ridden lives in fly-blown poverty. That way lies the final erasure of the faith under the grinding wheels of Western modernity. You have to sup with the devil, study his arts and his sciences without succumbing to that empty life of atomised secular materialism presented as the unavoidable correlate.

Hence his appointment to this grand office with its modern computing and communications infrastructure and its large prayer-carpet at the edge of which he kneels. His course is not long or even particularly difficult. It is merely mandatory in the final year and Miss Al-Amir seems destined to fail.

The students here have mostly come from traditional families. For once, a degree of selection by merit rather than wealth or influence has been enforced. They are uniformly unprepared for the culture shock – exposed to a cacophony of new ideas, forced to think for themselves. It’s not surprising that so many abandon their past certainties, their faith. It’s not too amazing that they think him a hopeless anachronism, an outdated authority figure with an obsolete ideology. Most of the students pay lip service to his teaching, passing his course through hypocrisy. Some of the more intelligent and principled fight or ignore him, and they of course will fail. This is normal in his country.

Sahar is one of these. She’s taken with western ways, makes no secret of her disdain for the old superstitions. Maths and computer science centre her new life. Her first two essays have been disasters: alternately ignorant and satirical. She is here is to discuss the final assignment which will most likely be no different and will cause her to fail her degree. Gamal admires her determination not to play a game she despises while despairing of her parochial lack of insight and mourning the likely consequences for her future (or lack of one).

Sahar Al-Amir knocks at the door and then pushes it open a fraction. Dr Khaled motions her into the room, beckoning her to kneel at the far side of the prayer-carpet. He can see at once that she is nervous as she settles herself down. Her black abaya is sloppy and loose while the material covering her hair is awry. This is not a good start. He speaks to her sharply – “Put your knees together!” She looks at him intensely and pulls off her badly-arranged headscarf. Blond ringlets tumble down her shoulders while her gaze never falters.

Gamal recognises at once he’s in a situation: this is not in any kind of script. He suppresses a reprimand and waits, suspicions confirmed as Sahar slowly pushes her robe off her shoulders to reveal her breasts, small and pert. She moves her hands down to her waist, pulling her robe apart and draping it on the carpet behind her. And now she strikes a pose, pulling her head back, pushing out her chest and spreading her knees farther apart. Her gaze never leaves Gamal’s face, her mouth opens slightly as she nervously flicks her tongue over her lips.

Dr Gamal Khaled has never been in this situation before but he’s heard plenty. Miss Al-Amir is indeed a vision of nakedly available loveliness, an erotic sculpture posed before him and part of him is signalling a very male response. But Khaled is an intellectual and at times like this it’s the rational, calculating part of him which takes control. Sahar has clearly reached the end of whatever makeshift plan she had for this afternoon and to prolong the silence further will surely lead to deeper humiliation. He is a teacher: now he must teach.

“Well, Miss Al-Amir,” he says, “I take it that this display is not unconnected with your final assignment? I am sure it has nothing to do with any charms I may or may not possess. Now, let us leave to God the appreciation of what He has created and cover yourself so that we may begin the tutorial.”

These kind words break the dam, and Miss Al-Amir bursts into tears. Gamal continues to kneel patiently, relaxed but unmoving until the snuffles cease. The contract they then negotiate puts the recently concluded display behind them, agrees that Sahar will participate in further coaching and that she deigns to take seriously the concept of a spiritual dimension to life – as a working hypothesis. Perhaps she will pass after all.

After Sahar has departed, Gamal Khaled reflects. This was not a serious attempt to seduce him, the stuff of academic folklore everywhere. Sahar has no skills whatever in that department. No, it was an act of desperation, a crisis, and sometimes only a crisis will break down the walls of the mind and let us make progress.

And now, he thinks wearily, he will have to write his report for the secret police.


Back to "Stories".