I met a fellow called Tim Kruger this week, who was keen to tell me about his idea for a process to suck carbon dioxide out of the atmosphere. (NB: Kruger and I both used to work for Shell, and Shell has also provided some seed money to him.)

Here’s the thinking:

    * First, you heat limestone to a very high temperature, until it breaks down into lime and carbon dioxide.
* Then you put the lime into the sea, where it reacts with carbon dioxide dissolved in the seawater.

The important point is that when you put lime into seawater it absorbs almost twice as much carbon dioxide as is produced by the breaking down of the limestone in the first place.

This has the effect of reducing the amount of carbon dioxide in the atmosphere. It also helps to prevent ocean acidification, another problem caused by the increase in the amount of carbon dioxide in the atmosphere.

If done on a large enough scale it would be possible to reduce carbon dioxide levels back to what they were before the Industrial Revolution.

Apparently, the pure CO2 produced in stage 1 is potentially a useful product - unlike the emissions from burning fossil fuels. And although the process is hugely energy-intensive, Kruger hopes to use “stranded energy” - flared natural gas, solar energy in desert regions, and other situations where energy is available but too far from civilisation to be much use.

Will it work? My natural scepticism says not: too many weak links in the chain. But it’s not absolutely impossible.

Why am I mentioning it? Two reasons:

1) It is always worth remembering that CO2 emission-reduction is not the only possible way to deal with climate change. This is a problem that will play out over the next century, and over the next century, our technology is likely to advance along the way. (But not necessarily in a helpful direction, unless we have a credible price on carbon emissions.)

2) I’m also intrigued by Kruger’s “anti-patent” space. He’s trying to mimic the open source software model for a non-software project. Reckon that part of the idea might work and/or catch on? I’ve no idea.

Other nutty-sounding methods for taking carbon dioxide out of the atmosphere are here.

I’m late to the party, but a pokerbot beat some decent human players earlier this month. This is not a huge surprise: when I visited the artificial-intelligence version of the World Series of Poker in Las Vegas in 2005, it seemed likely that this was coming. It will take a little more time to be sure, though: there is a great deal of variance in poker. (Steve Levitt has more on that point - always interesting.)

I’ve held off publicising Walkit for a while, because the founder is a friend of mine. But since the site is getting lots of well-earned publicity I’m happy to chip in. Walkit is a website that will work out walking routes across London and several other British cities (Edinburgh, Birmingham, Newcastle, and others - with more on the way). It will calculate your calorie burn and your CO2 emissions saved and all sorts of nonsense, but basically it finds good, low-pollution routes with realistic journey times. Check it out: some urban journeys are surprisingly quick by foot, and far less stressful than public transport or car.

Seth Godin’s email checklist:

1 Is it going to just one person? (If yes, jump to #10)
2 Since it’s going to a group, have I thought about who is on my list?
3 Are they blind copied?
4 Did every person on the list really and truly opt in? Not like sort of, but really ask for it?
5 So that means that if I didn’t send it to them, they’d complain about not getting it?
6 See #5. If they wouldn’t complain, take them off!
7 That means, for example, that sending bulk email to a list of bloggers just cause they have blogs is not okay.
…
10 Have I corresponded with this person before?
11 Really? They’ve written back? (if no, reconsider email)…

The list goes on to 36 and almost all of the advice looks good to me.

Beyond the practicality of the checklist, it raised a question in my mind. Some of Seth’s advice was routinely flouted in the early days of mass email (I’m thinking 1995-1999). For instance, many people forwarded jokes and virus warnings. These days they are rare, especially as a proportion of all the email that is sent. Other advice (such as, “don’t admonish people not to print this email”) would have been superfluous ten years ago and is now very widely ignored.
So my question is, what determines why some bad email habits die out and others thrive and multiply? Or is this just the unpredictable outcome of a mysterious process of evolution?

Ed Castronova writes to inform me that:

With generous support from the MacArthur Foundation, we have created a fun game environment and used it to conduct a month-long experiment. Our experimental question (kept secret up to now) was: Are fantasy game players economically “normal”? Or on the contrary, when they make themselves into elves and dwarves and hobbits, do they stop taking economic decisions seriously? We created two virtual worlds, one an exact copy of the other, except that in the experimental world the price of a simple healing potion was twice as high as in the control. If people are taking prices seriously in this fantasy environment, they should buy fewer of the potions when potions are more expensive.

At stake here is the entire idea of using virtual worlds as a Petri dish. If fantasy gamers behave in ways that violate our most basic assumptions of economic normalcy, then it makes no sense to use virtual worlds to study large-scale economic behavior. If, conversely, fantasy gamers seem to be normal economic agents, then perhaps some of the behavior in virtual worlds does indeed generalize to the real world. If so, then we can consider using virtual worlds to conduct controlled experiments at the macro scale of society, where our most pressing problems seem to live (natural resource management, intercultural mistrust, information security, disease).

The initial findings of the Arden experiment will be released during the International Communications Association meetings in Montreal next weekend. The session we’re part of is this one:

“High Density Session: The Web 1.0, 2.0, and Beyond”
Time: Sat May 24, 3:00 - 4:15pm
Place: Le Centre Sheraton / Drummond West

See the entire schedule for Saturday here:
http://convention3.allacademic.com/one/ica/ica08/index.php?click_key=3&cmd=Multi+Search+View+Program+Load+Scheduled+Times&schedule_day=2008-05-24+00%3A00%3A00&PHPSESSID=e76b3aa3a0d5c7b574ab10b60c31733e

I would be mightily surprised if the answer is not “yes”, but let’s see. And the question strikes me as foundational. More on Castronova here and here and especially (in this context) here. More information when I know it.

Clay Shirky reports on a conversation with a TV producer, after describing a flurry of activity on the Pluto page:

She heard this story and she shook her head and said, “Where do people find the time?” That was her question. And I just kind of snapped. And I said, “No one who works in TV gets to ask that question. You know where the time comes from. It comes from the cognitive surplus you’ve been masking for 50 years.”

So how big is that surplus? So if you take Wikipedia as a kind of unit, all of Wikipedia, the whole project–every page, every edit, every talk page, every line of code, in every language that Wikipedia exists in–that represents something like the cumulation of 100 million hours of human thought. I worked this out with Martin Wattenberg at IBM; it’s a back-of-the-envelope calculation, but it’s the right order of magnitude, about 100 million hours of thought.

100 million hours sounds like a big number, but as Clay goes on to describe, it’s tiny. 100 million hours is about 20 minutes per US citizen - roughly the amount of time collectively spent watching advertisements in a typical weekend. (That’s Clay’s number: I’d have guess it only took an evening for each American to watch 20 minutes of adverts, but I am clearly a TV-pessimist and out of touch.) HT: Virtual economics.

Update: My TV pessimism was correct - see Comment No 2 from Gerald, below. Thanks, Gerald!

The technology is here, HT Seamus:

TimeMachiner is a new mini-app that lets you email people in the future. Use it to remind yourself to do something that you’ll more than likely forget, keep your future self on the straight and narrow, even wish your friends happy birthday…

Useful for reminding yourself of last year’s resolutions, but beyond that, what economically-interesting applications can y’all suggest?

Update: A loyal reader comments:

I can suggest one interesting experiment. Put up a website which provides this as a service. On the front page, put an easy-to-use form. Make the service free and open. Then have no privacy policy at all, so you can do what you like with all the email addresses you harvest. Then all the helpful bloggers will do your marketing for you. (Step 3: Profit!)

Good point…

I wrote about the dilemma of passwords here: they must be impossible to remember, change frequently and never be written down. Now a kind fellow called Sean Gilbertson has sent me a pamphlet on his “Cryptogic” system. He suggests combining a fixed password section (eg TimFT) with a variable password. For instance an Amazon password might be 3TimFT3 because Amazon has three syllables and three vowels, while an eBay password would be 2TimFT2 because eBay has two syllables and two vowels. Pick your own simple rule for deriving a variable password.

It’s a nice enough system, and does deal with the important problem of using different passwords for different sites - which was the original question! Still doesn’t help much with the requirement to change passwords constantly, alas…