Really?

John Quiggin46 Comments

The New York Times has an article by Brian Greene, a professor of physics and mathematics at Columbia about Einstein’s famous equation E=mc². In it he says:

The standard illustrations of Einstein’s equation – bombs and power stations – have perpetuated a belief that E = mc² has a special association with nuclear reactions and is thus removed from ordinary activity.

This isn’t true. When you drive your car, E = mc² is at work. As the engine burns gasoline to produce energy in the form of motion, it does so by converting some of the gasoline’s mass into energy, in accord with Einstein’s formula. When you use your MP3 player, E = mc² is at work. As the player drains the battery to produce energy in the form of sound waves, it does so by converting some of the battery’s mass into energy, as dictated by Einstein’s formula. As you read this text, E = mc² is at work. The processes in the eye and brain, underlying perception and thought, rely on chemical reactions that interchange mass and energy, once again in accord with Einstein’s formula.

I only did high school science, but I’m sure I remember learning the exact opposite of this claim, that chemical reactions like combustion leave mass and energy unchanged, only converting some of the chemical energy in the fuel into kinetic energy, and some into heat, with a net increase in entropy. Only nuclear reactions, I was taught, converted mass to energy. Wikipedia seems to back this up, though it isn’t absolutely unambiguous.

Can anyone set me (or, less plausibly, Greene) straight here?

fn1. As an aside, I also remember reading that a more correct version would be E=M. The term in c² just reflects a poor choice of units in the metric system. But maybe that’s wrong too.

Toll opposes privatisation

John Quiggin10 Comments

Today’s AFR (subscription only, and not yet accessible on Factiva, but on p 10 of the print edition) reports the head of major private transport companies Toll Holdings opposing the privatisation of rail infrastructure, on the grounds that “

if one of those infrastructure groups got hold of the rail network [owned by Macquarie Infrastructure Group, as noted in the report-JQ] it could go the way of Sydney airport. We could see costs jacked up

Mr Little also said that private infrastructure groups would not invest adequately.

I made some similar points in my piece on Telstra a couple of weeks ago, and in my latest piece (over the fold), but this is the first time I’ve seen a large private corporation acknowledging the poor performance of privatised infrastructure networks.
Read More »

Weekend reflections

John Quiggin5 Comments

Weekend Reflections is on again. Please comment on any topic of interest (civilised discussion and no coarse language, please). Feel free to put in contributions more lengthy than for the Monday Message Board or standard commnets.

Intransitivity

John Quiggin7 Comments

From today’s NYT

“Even though DeLay has nothing to do with Frist, and Frist has nothing to do with Abramoff, how does it look? Not good,” said William Kristol, a key conservative strategist and editor of The Weekly Standard.

Unfortunately for Kristol’s rhetorical exercise, the relation “has nothing to do with” is not transitive, a fact of which he is presumably aware, given this choice of example.

From the previous para in the same story

the string of ethical issues so close together – including the indictment and continuing investigation of the Republican lobbyist Jack Abramoff, who was close to Mr. DeLay … is a source of anxiety in Republican circles.

Saddam trial

John Quiggin24 Comments

Gary Bass in the NYT comments on the possibility that Saddam could be sentenced to death and executed for a 1982 massacre of about 100 villagers, without ever being brought to trial on the main array of charges against him, including killing political rivals, crushing the Shiite uprising in southern Iraq in 1991, invading Kuwait in 1990 and waging the genocidal Anfal campaign against the Kurds in 1988, including gassing Kurdish villagers at Halabja. As Bass says,

 A thorough series of war crimes trials would not only give the victims more satisfaction but also yield a documentary and testimonial record of the regime’s crimes.

But looking at this list raises a more basic question. Why hasn’t Saddam been charged with any crime more recent than 1991?[1]. In the leadup to the war, and in its aftermath, it was routinely claimed that Saddam’s regime, at the time it was overthrown was among the most brutal dictatorships in the world. Even among opponents of the war, including myself, hardly anyone doubted that the regime routinely practised murder and torture. Why then aren’t there any charges covering this period? Presumably both documents and witnesses are more readily available than for a crime committed more than twenty years ago.
Read More »

Meeting the economists

John Quiggin6 Comments

I’ve been at the Conference of Economists in Melbourne for the last few days. I econobloggers, Stephen Kirchner and Andrew Leigh[1], as well as Andrew’s co-author Justin Wolfers and lots of old friends and sparring partners. I gave a paper on Learning and Discovery, an attempt with Simon Grant to unravel the knotty problem of unknown unknowns. You can read a more accessible summary Unknownunknowns0509here

Olivier Blanchard gave quite an interesting paper on European unemployment, on which I’ll try to comment further. I also found out what’s wrong (and right) with the bootstrap (an econometric technique) and saw an interesting ranking of economics departments, which showed that one of my former homes was ranked #2 in Australia on per capita research output just at the time when it was closed down as part of the reform process.

The singularity and the knife-edge

John Quiggin21 Comments

I’ve been too busy thinking about all the fun I’ll have with my magic pony, designing my private planet and so on, to write up a proper review of Ray Kurzweil’s book, The Singularity is Near. The general response seems to have been a polite version of DD’s “bollocks”, and the book certainly has a high nonsense to signal ratio. Kurzweil lost me on biotech, for example, when he revealed that he had invented his own cure for middle age, involving the daily consumption of a vast range of pills and supplements, supposedly keeping his biological age at 40 for the last 15 years (the photo on the dustjacket is that of a man in his early 50s). In any case, I haven’t seen anything coming out of biotech in the last few decades remotely comparable to penicillin and the Pill for medical and social impact.

But Kurzweil’s appeal to Moore’s Law seems worth taking seriously. There’s no sign that the rate of progress in computer technology is slowing down noticeably. A doubling time of two years for chip speed, memory capacity and so on implies a thousand-fold increase over twenty years. There are two very different things this could mean. One is that computers in twenty years time will do mostly the same things as at present, but very fast and at almost zero cost. The other is that digital technologies will displace analog for a steadily growing proportion of productive activity, in both the economy and the household sector, as has already happened with communications, photography, music and so on. Once that transition is made these sectors share the rapid growth of the computer sector.
Read More »

Amazing!

John Quiggin13 Comments

A great win for the Swans with a game-saving mark in the final seconds. And finally a reward for the South Melbourne faithful who’ve gone a biblical lifetime (threescore years and ten, with a couple over) without a flag. Tim Dunlop is similarly stunned.