Gerry Canavan

the smartest kid on earth

Several for Tuesday

with 3 comments

* Mark your calendars: Today Springsteen announced his U.S. tour dates.

* I guess today we’re all pretending we didn’t already know Mitt Romney is obscenely super-rich—though I did like Steve Benen’s observation that Romney would be in the top 1% based on the income he makes for doing nothing in a single week. A comparison between Romney, Gingrich, and Obama that’s genuinely pretty stunning. Six Facts About Mitt Romney’s Tax Returns.

“When Online Gambling Is Legalized, Facebook Will Be A $100 Billion Company.”

For almost every diagnosis, women reported higher average pain scores than men. Women’s scores were, on average, 20 percent higher than men’s scores, according to the study.

* And the Economist asks: Where is everybody?

In a paper presented recently to the meeting of the Amercian Mathematical Society and the Mathematical Association of America, they reckon the odds are rather long. To arrive at their conclusion Dr Hair and Mr Hedman assumed that outer space is dotted with solar systems, about five light years apart. They then asked how quickly a single civilisation armed with the requisite technology would spread its tentacles, depending on the degree of colonising zeal, expressed as the probability that intelligent beings decide to hop from one planet to the next in 1,000 years (500 years for the trip, at a modest one-tenth of the speed of light, and another 500 years to prepare for the next hop).

All these numbers are necessarily moot. If the vast majority of planets is not suitable, for instance, the average distance for a successful expedition might be much more than five light years. And advanced beings might not need five Earth centuries to get up to speed before they redeploy. However, Dr Hair and Mr Hedman can tweak their probabilities to reflect a range of possible conditions. Using what they believe to be conservative assumptions (as low as one chance in four of embarking on a colonising mission in 1,000 years), they calculated that any galactic empire would have spread outwards from its home planet at about 0.25% of the speed of light. The result is that after 50m years it would extend over 130,000 light years, with zealous colonisers moving in a relatively uniform cloud and more reticent ones protruding from a central blob. Since the Milky Way is estimated to be 100,000-120,000 light years across, outposts would be sprinkled throughout the galaxy, even if the home planet were, like Earth, located on the periphery.

Crucially, even in slow-expansion scenario, the protrusions eventually coalesce. After 250,000 years, which the model has so far had the time to simulate, the biggest gaps are no larger than 30 light years across. Dr Hair thinks they should grow no bigger as his virtual colonisation progresses. That is easily small enough for man’s first sufficiently powerful radio transmissions (in the early 20th century) to have been detected and for a reply to have reached Earth (which has been actively listening out for such messages since the 1960s). And though 50m years may sound a lot, if intelligent life did evolve more than once, it could easily have done so billions of years before this happened on Earth. All this suggests, Dr Hair and Mr Hedman fear, that humans really do have the Milky Way to themselves. Either that or the neighbours are a particularly timid bunch.

3 Responses

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  1. I saw another study that showed women tolerate pain with a duration better than men, while men tolerate acute pain better than women.


    January 24, 2012 at 3:04 pm

  2. Just a note: reported pain could be almost entirely culturally conditioned (men are conditioned to believe x is not that bad).


    January 24, 2012 at 3:08 pm

    • I was curious how they dealt with that issue. It seems insurmountable when you’re relying on self-report.


      January 24, 2012 at 5:50 pm

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