Review of 'Deep Down Things' by Bruce Schumm

Review posted at Amazon.com here.

Fed up with useless metaphors which equate the Higgs particle with hangers-on at a party slowing a celebrity’s passage? Exasperated at continual references to Lie algebras and gauge theories, which are never explained?

In Peter Woit’s recent book ‘Not Even Wrong’, he comments (p. 205) that relativistic quantum field theory is not even studied until the second or third year of graduate school. For the rest of us, there is ‘Deep Down Things’.

Schumm’s objective is to take us on a conceptual tour of the Standard Model of quantum mechanics, without requiring a mastery of the technical apparatus. The first half of the book introduces the four fundamental forces, wave-particle duality and the wave function itself. The approach is historical and visual - plenty of Feynman diagrams - and Schumm assumes the reader is happy with complex exponentials. By chapter 5 we are deep in the eightfold way, and the classification of quarks, leptons (electrons, muons, neutrinos) and bosons (the force quanta).

Chapter 6 begins the process of diving deeper with a discussion of Lie groups and Lie Algebra, motivated by plenty of examples. A Lie group is defined via: (i) a continuous set (i.e. a real or complex manifold such as R^n or C^n) with (ii) operators which are continuous functions over the manifold. Chapter 7 introduces Noether’s theorem: ‘to every differentiable symmetry generated by local actions, there corresponds a conserved quality’ and this is linked with symmetries under transformations by the Lie group operators (such as rotations in isospin space which interchange protons and neutrons).

Introductory quantum mechanics courses talk about the physical irrelevance of the phase of the wave function when it comes to the calculation of probabilities of observables. We thus have the concept of global phase invariance. However, this is unphysical - we cannot have the universe adjusting phase by the same amount everywhere at the same time. Yang and Mills in the mid-50s proposed to force the wave function to be invariant under local changes of phase: it turns out the only way to achieve this is to add a new term of the form gA(x)psi(x) where g is a charge parameter associated with the particle, psi(x) is the wave function and A(x) is a new term which turns out to be the field potential function for the relevant force field (electromagnetic in chapter 8). The freedom of choice in choosing the function A is called a gauge freedom, hence gauge theory.

Choose a fundamental particle. Write down its wave function. Identify the spaces in which the particle participates (space-time, isospin, ...). Identify the Lie group which rotates the wave function (state vector) in each of these spaces - U(1), SU(2), SU(3). By the principle of local phase invariance, adjust the original wave function with gauge terms gA(x)psi(x) as above. From making this work mathematically, out pop the corresponding force quanta (= the number of generators of the corresponding Lie algebra above). As the chapter heading puts it: ‘Physics by Pure Thought’!

Chapter 9 explains how the standard model assigns a mass of zero to all force-field quanta. Any attempt to add mass destroys the local phase invariance that we just discussed. The only way to retrieve the situation is to assume the existence of a new field (the Higgs field) which somehow pervades the universe and which interacts with non-zero-mass force quanta (via the weak force) in a ‘screening’ way which gives them mass. The Higgs field is also responsible for the masses of quarks and leptons. If this is true, there should be a Higgs particle within reach of CERN’s Large Hadron Collider in 2007.

This is a really excellent book. If you dimly recall how to solve a differential equation, and are unfazed by the notion of an abelian group, then this book is accessible. By book-end you have the sense that you ‘get’ the big picture of the standard model and its remaining conceptual weaknesses. I would say that if you were an undergraduate interested in theoretical physics and wanted a tour d’horizon, this is the one book which will give it (Penrose’s ‘The Road To Reality’ is still too difficult for this purpose).

Newsnight opens the door a chink

Professor Robert Pape, who has analysed the motives of hundreds of suicide bombers, said on Newsnight (BBC Television news analysis show) that their motives are not religious. Instead, the bomber harbours a deep resentment that the country he or she is attacking has an unwanted and unjust presence & influence on the land with which the bomber emotionally identifies.

Professor Pape said this view was not popular with western leaders, but was compellingly supported by his reseach (he has a book - link here).

On another recent Newsnight programme, a speaker from the radical muslim group Hizb ut Tahrir unreservedly condemned alleged british suicide bombers, but agreed that his organisation stood for the restoral of the caliphate across the middle-eastern Sunni community.

Recall that Osama bin Laden's original justification of al Qaeda attacks was the American military presence in Saudi Arabia, home of two of the sacred sites of Islam.

Thought experiment. The west gets its tanks off the lawns of the Sunni umma in Iraq, Afghanistan and ceases support for regimes in Jordan, Egypt, Saudi etc. What is the likely outcome as desired by radical Islam?

1. An (oil-fuelled and very rich) caliphate built along Taliban lines adhering to Wahhabi doctrines across the middle-east.
2. An exterminatory war against Israel, which could go nuclear.
3. A powerful force polarising muslim communities in every European country with sizeable muslim populations (at least England, France, Spain, Italy) and bent on imposing sharia law locally.
4. Secularised Turkey is in real trouble.
5. Spiralling Sunni-Shia antagonism leading to wars of religion.

Perhaps the west, which had the benefits of the renaissance and the enlightenment (which were absolute, and not relative advances for humanity), has some responsibilities not to let this outcome occur by default, even putting aside the material interests of the economics of oil and those of national security?

I think I'm saying that the easy option to let these guys have what they want is worse than the current policy (flawed as it is due to over-reliance on hard power; incompetent execution; and the wilful disregard of the need of Palestinians for a viable state, regardless of the concerns as to who would end up running it).

Balloons over Basingstoke

This afternoon to Basingstoke for the balloon festival.

Here is a picture of the most risque balloon.

The event, at the War Memorial Park, was hard to find through Basingstoke's one-way system, but after we had parked-and-rode, the first thing we saw was a parachute display team - you can see it on the video here.

[10.6 MB in .wmv format, keep watching at the blank section in the middle].

The balloons launched en masse after 6 p.m. Here is a picture of me in front of one of the balloons. The joke goes that you are meant to figure which is which.

We had a good afternoon, and on the way back to the car we were over-flown by three paramoteur pilots (paragliders with back-mounted engines to keep them up) . Sounds like fun.

The video, BTW, has a few seconds of black in the middle - don't have too much time to edit well. Stay with it for the second half, where the launching balloon's basket collides with a nearby balloon: cue gasps from the audience at this near tragedy ...

It's 28 centigrade this evening and humid - I just knew this Greenhouse Effect would be double-edged ...

Isle of Wight

First of all a big hello to my brother Adrian, who occasionally checks out this blog on Wednesdays with his student. I hope this one isn't too touristy!

Sunday we went to the Isle of Wight, about 50 minutes drive and an hour's ferry (via Southampton) from where we live. Our first tourist encounter was with Osbourne House, Queen Victoria's former residence on the island. Here's a picture of Clare in the wonderful gardens, with a view looking back towards Portsmouth.


Later we upped and migrated to Ryde, which from the pier reminded us curiously of the equally-touristy Fisherman's Wharf in San Francisco (in a little way of course - and we bore you here as experienced world-travelers ... *).


Then we came back via Cowes. Consequent upon it being Cowes Week, the place was full of yachties. We had a competition to count the number of burley, middle-aged nautical types with gorgeous young things hanging off their arms. I got three in 25 minutes, so I guess I wasn't paying attention ... (go figure!).

* No, we are not showing off - this is called irony ...

"On interstellar warfare"

As I wait for the page-proofs of my soon-to-be-published book (see opposite), my thoughts turn to writing a second book. No more on telecoms though!

I have two thoughts.

I could do something on personality theories. There is a gap in the market to look at the Myers-Briggs approach vs. the academic 'Five Factor' model vs. evolutionary psychology + the results of recent brain-imaging research. I can think of a number of powerful ideas and insights from combining these disparate schools of thought and I think the results would sell.

My other idea is reflected in the title of this piece - inspired by the famous "On Thermonuclear War". Briefly, my proposition is that any alien civilization we discover will be exceptionally aggressive and dangerous (a good self-description, don't you agree?) and that we should aim to wipe them out immediately. I will look in detail at the new hyper-telescope technologies (link) which may give us the same view of alien planets as orbital satellites give us of the earth today. I then survey methods of planetary extermination including:

• asteroid bombardment
• relativistic weapons
• flaring the star
• biological weapons
• sociological weapons.

Finally I look at options for interstellar travel, so that we can inspect the resulting wreckage and then colonise. (I also analyse our losing options).

Does this sound extreme? I think a civilization which could absorb The Simpsons is ready for my book, and I would expect it to sell by the shed load.

Joking in bad taste aside, you are invited to read the Book Proposal by clicking here.

Enjoy (expecially if you are a prospective publisher)! And actually, I think the one book could cover both of my ideas, via 'exopsychology'.

Inflation and deflation

Friday evening we packed up the car and in the blustery heat of a July evening, departed for a campsite at the little seaside town of Swanage, in Dorset. A morale-lowering sequence of events then followed.

The campsite itself was OK-ish, just that little bit down-market (no defined pitches, poor washing/WC facilities). The ground itself was stony, a nightmare to get the tent-pegs in. A warm wind was gusting and rocking the tent, so I cared more than usual about this.

8 p.m. and Clare was urging me to get in the car and drive to the Swanage beach front so we could get to eat. I then noticed that my air-bed had deflated: yep, it had a leak. I guess I wasn't the most sparkling dinner companion at that not-entirely-perfect Italian restaurant; my mind kept anticipating a night on the car seat. After the meal, we wandered the high street and came across a shop - just closing- - which sold beach paraphernalia. Hearing our tale of woe, the store owner was prevailed upon to sell us a Lilo airbed for £2.99. Not ideal, but better than the stony ground for the night to come.

I guess it must have been 2 a.m. when I realised that the Lilo had also developed a leak and had deflated under me. As the tent shook around me, I found that sleeping on your back is best in situations like this - the hip then doesn't dig into the hard surface.

We spent Saturday on the beach at nearby Studland. Crowded but pleasant. I watched the wind-surfers being blown over by the gusts to the complex sound-symmetries of the 'Art of Fugue' on my MP3 player. We abandoned our second night camping, however, and stopped off at Corfe Castle on our way home. An ancient (William the Conqueror) castle blown up by the parliamentarians after the civil war.

Clare standing in front of the Keep, fenced off as it's unstable.


This is the view of the village of Corfe Castle from the Keep (and myself).


Former Prime Minister John Major made a good point on TV this morning about the current Israeli-Hezbollah conflict. To paraphrase his argument (addressed to the Israelis): "Can you kill them all? No? Then you will eventually have to cut a deal with them. Does the current campaign make sense in that context, regardless of how good it feels?"

A comment of my own: I am mindful that it takes two to negotiate.

Einstein's view of death

Albert Einstein wrote the following, in a letter of condolence to the sister and son of his long-time closest friend, Michele Besso, upon his death, four weeks before Einstein's own (18th April, 1955).

"Now he has departed from this strange world a little ahead of me. That means nothing. People like us, who believe in physics, know that the distinction between past, present and future is only a stubbornly persistent illusion."

Thinking of oneself four-dimensionally is challenging. We think the phrases 'past self' and 'future-self' are metaphors, but actually they are literally true. Somewhere 'up-time' is the future you and me, just as real as myself at this moment of writing, or your moments of instantaneous reality as you read these words.

My past self-slice can communicate with a future self-slice through use of media. If I read this blog later, that's exactly what will happen. I try to imagine that future self, but it's hard. It's not a dialogue: my future self can't answer me back.

---

Note added on December 10th 2025

Hi, it's your future self just re-reading this post. I feel quite real I have to say but it's been a while - nineteen and a half years. You'd be pleased to know it turned out pretty well.

Up-time from here is the now-more-imminent moment of my own death.

I sure hope that guy is having an easy time of it - but he can't tell me...

---

Exercise and Ed Witten

Having spent six months running a couple of miles three times a week, and then stopping in February due to recurrent knee, thigh and hip pains (too much weight in the middle!), I have finally re-converged to slobdom. It feels bad.

I have therefore determined to buy a bike, and do 30 minutes of serious biking three times a week as a non-impact aerobic thing. I am inspired (only a small amount) by 'Le Tour' of which Clare is an avid fan. Round to the bike shop, then, on Saturday.

Reading 'Not Even Wrong' one is struck by the sheer, sustained brilliance of Ed Witten. This puts whatever intellectual pretensions one might have completely in their place. And that's from a distance - whatever must it be like for his close colleagues?

Kafka - the computer game

I am reading Kafka's The Castle at the moment. The hero, K., is a land surveyor who, through bureaucratic error, has made the long and difficult journey to the Castle. He is marooned in the village, where he meets all kinds of bizarre people in his doomed attempt to either visit the officials in the Castle, or get any kind of sense out of them. As is usual in Kafka, there is a sense that the hero is living in a wakened dream.

Genre literature (thrillers, hard SF) is susceptible in a more or less crude way to computer gaming even today. If the focus is depiction of physical reality, plus crude behaviours of game-agents which speak to our primary impulses (kill it!) then the technology is good enough.

How would you 'do literature' as a computer game? The point of Kafka's work is the crazed environment combining local sense with systemic irrationality made manifest through K.'s conversations with everyone else. This is coupled with K.'s reactions, both his immediate mood swings and his cumulative reaction to events through the novel.

Kafka, being a genius, could script all this, but if the game player is to be K., then the game agents have to be human-level personalities with back stories, personalities and roles.

This is why there is a yawning gulf between computer games - interactive media - and literature.

A conversation with Danny

"Danny showed me his video parser. I gave him a .3gp video of my son, newly arrived back from snowboarding in Canada. The video, from my camera-phone, was tiny and grainy. Danny's program read frame after frame, displaying each magnified pixel map. It was incomprehensibly to my eyes.

"The program does standard things like edge-detection, object-inference and finally scene-reconstruction. It's based on the detailed models of people and objects stored in its object-database. The parsed result is a high-resolution 3D animation model similar to those we use to generate video games. We can then invert the process and render this model at any resolution we choose."

Danny showed me his processed video based on my original postage-stamp movie, but it was now rendered on a high-definition TV screen. And it was perfect.

"You do realise the implications, don't you?" Danny said. This cinematic version of your video is a reconstructed reality, a kind of 'informed hallucination' based on your original coarse and tiny video. And that too was a kind of hallucination of reality, formed from pixels illuminated by your camera lens.

"And as you sit there looking at me, your brain is doing just the same thing" he continued. "You have no access to the 'real me'. Your 'view' is entirely reconstructed from retinal images on the back of your two eyes: tiny, noisy and upside-down neuronal 'bit-maps'. It looks like you're seeing the world, but you're hallucinating a view based on retinal image processing."

He grinned. "Intellectually you know it, but you don't really believe it, do you?"

Miffed, I replied. "You're sitting there looking at me and being amused. Consider this - the 'you' being amused is just the activity of 100 billion neurons doing their thing behind your eyes. 'You' are no more than the sum of their activity. How does that work, d'you think? And do you really believe it?""