Saturday, August 16, 2008

Gravity is Leaking into the 4th Dimension.

Just thought you'd like to know that.
Watch this: "The Elegant Universe" - from Nova.... great stuff. Will blow mind.

Thursday, August 14, 2008

Map Confusion, Why is North Up?, Magnetic vs True North, Polar Motion
On maps, why is North always up? Apparently, it's been this way only since the middle ages when Ptolomey's maps were rediscovered. Before that, it was a free-for-all.

Even the word "orientation" refers to the fact that the "orient" i.e. the "East" was placed in the UP position- North thereby being moved to where West is today. According to baby-naming websites scoured prior to my son's birth- the name "Benjamin" means "son of the right hand" ... and is also translated as "Son of the South". This makes sense if the map has East at the top, or if you are facing the "East" towards Jerusalem- presumably you'd have to be West of the "Middle East" for that to be true!

Even more confusing is the fact that Magnetic North keeps moving , flipping around like a fish in a bucket. It's on it's way from Canada to Siberia at 41km/year as we speak. Actually, it may jiggle up to 85km in a single day and apparently is rarely found where it is supposed to be! average path on disturbed days

Compasses - despite popular belief- do not point North, or even to Magnetic North! Compasses point along LOCAL magnetic field lines- these are wobbly, and depend on moving flows of iron and nickel deep within the earth. The difference between where your compass is pointing and where true (geographic) north is, is known as Magnetic Declination. Off the coast of Madagascar, this can be up to 40 degrees!

Image:IGRF 2000 magnetic declination.gif
In any case, the north pole of any magnet (including that in a compass) is attracted to another south pole- hence the North Magnetic Pole should really be renamed "The Earth's South Magnetic Pole Which is Currently Located Vaguely Around Somewhere Near True North".

Even True North- the geographic North Pole is moving ("Polar Motion") - albeit very slowly, and very slightly. It takes a cycle of about 400 years, but the point the Earth is twisting around moves by up to 20m. (see chart below). I guess we are tumbling rather than twisting our way around the sun. Fascinatingly, some of this is due to melting of the Greenland ice sheets and the subsequent rebound of the unburdened earth! Global warming is literally throwing the Earth "off kilter".

Finally, thanks to "precession" - like the wobbling of a spinning top- True North points to varying regions of space. Currently (in the northern hemisphere) it points to Polaris (aptly named!).
Image:Earth precession.svg

Harper Lee, Laptop Warmth, Erythema Ab Igne

Just got my MacBook battery replaced - it died, they took it, they replaced it- no cost. Why? Because it's less than 6 months since they last replaced it. Great idea - i think i'll take my MacBook down to the MRI department and rub it on the magnet every 11.99 months.
I remember reading an interview with the reclusive Harper Lee (author of 'To Kill a Mockingbird') where she expressed a view that paperbacks will neve die because "who has ever heard of anyone curling up in bed with a laptop?". Obviously she has never owned a laptop - the heat generated by my MacBook battery is incredible ! There is a well described phenomenon in dermatology known as "erythema ab igne" - reticulate (netlike) erythema (redness) after prolonged exposure to infra-red radiant heat. It's often recognised on little old ladies' shins but is quite common nowdays on the anterior thighs from prolonged exposure to laptop heat. image “” cannot be displayed, because it contains errors.

Wednesday, August 13, 2008

Apparatchik Vs Apparatchnik

Russia and Georgia are all over the papers - but rather than spend time trying to work out the details on who's right and who's wrong (that would require 30mins on wikipedia and at the end of the day you can bet it's all about greed, corruption, oil and power)- i've got hung up on the word "Apparatchnik". Couldn't get it out of my head. An incessant loop. Try doing a google lookup (search term "Define: Appartchnik") - nothing! Most unusual.... but i DID find a really fascinating blog post about the word .. and whether it should be a chick or a nik?

Saturday, August 09, 2008