Monthly Archives: October 2009

Decimalising time

This is part of a work in progress…

To make teaching significant figures easier I’d like to decimalise time.


One 24-hour day would become 1 unit of time, six in the morning would be 0.25, midday would be 0.5 and six in the evening would be 0.75. Astronomers already do this with the concept of fractional days and the Julian calendar.


If you told someone to meet you at “0.5” (midday) then this could be any time between 0.45 (10:48) and 0.55 (13:12). If you asked to meet at “0.50” then this would be more specific, between 0.495 (11:52:48) and 0.505 (12:07:12). To be really specific (to within an “old minute”) you could specify “0.500” which would reduce the window to 0.4995 (11:59:16.8) and 0.5005 (12:00:43.2). The advantage of this is that any time during the day can now be specified to within any desired margin of error:
1 decimal point ± 2 hours 24 minutes
2 decimal points ± 14 minutes 24 seconds
3 decimal points ± 1 minute 26.4 seconds
4 decimal points ± 8.64 seconds


Decimalising time would also make calculations involving time a great deal simpler: no more need for modular arithmetic, just simple plus and minus. There would be no more worrying about AM and PM and no more need for the 24-hour clock.

Talking about Time

The accuracy implied by using two significant figures means that a percentage value would probably be accurate enough for most usages. Guest for a dinner party could be told “81 percent for 83 percent” which would be (approximately) equivalent to “seven-thirty for eight” (more accurately 19:26 for 19:55, though with the accuracy considerations above taken into account it could be any time between 19:19 and 20:02*).

Because the new unit of time would be a normal unit like any other, the standard (sub)multiple prefixes could be used: one centiunit would be about quarter of an hour and one milliunit would be about a minute and a half. For real accuracy microunits, equivalent to 0.0864s, could be used.



The simplest change would be to replace the 12-segment clock with a 10-segment one. The two-hands-twice-around movement would be replaced with a one-hand-once-around movement.


I’d prefer a complete redesign: I favour a progress bar style arrangement.


Progress bar clocks could be set up to gradually reveal a picture throughout the day; alarms are marked with a simple line (the alarm below is set for 20:30).


Your entire day would be visible at a glance the clock below shows the average 9-5 workday: sleep from midnight to six, work from 9 to 5 and then sleep from ten at night onwards.


Other variations on the progress bar idea are possible:


* This was the point at which I realised I had been thinking about this far too much. [Back]

2009 Ignobel Prizes


The Ig Nobel Prizes are awarded for research that “can not, or should not, be reproduced” or research that “first makes you laugh, then makes you think”. The 2009 prizes have just been awarded:

Prize for Mathematics

Awarded to Gideon Gono, governor of Zimbabwe’s Reserve Bank, for giving people a simple, everyday way to cope with a wide range of numbers — from very small to very big — by having his bank print bank notes with denominations ranging from one cent ($.01) to one hundred trillion dollars ($100,000,000,000,000).

Prize for Physics

Awarded to Katherine Whitcome, Daniel Lieberman and Liza Shapiro for analytically determining why pregnant women don’t tip over.

Reference: Whitcome, K.K., Shapiro, L.J., Lieberman, D.E. (2007) Fetal Load and the Evolution of Lumbar Lordosis in Bipedal Hominins, Nature, 450, pp. 1075-1078. doi: 10.1038/nature06342

Prize for Chemistry

Awarded to Javier Morales, Miguel Apátiga and Victor Castaño for creating diamonds from tequila.

Reference: Morales, J., Apatiga, M., Castaño, V.M. (2008) Growth of Diamond Films from Tequila, arXiv: 0806.1485

Prize for Biology

Awarded to Fumiaki Taguchi, Song Guofu, and Zhang Guanglei for demonstrating that kitchen refuse can be reduced more than 90% in mass by using bacteria extracted from the faeces of giant pandas.

Reference: Taguchi, F., Guofu, S., Guanglei, Z. (2001) Microbial Treatment of Kitchen Refuse With Enzyme-Producing Thermophilic Bacteria From Giant Panda Feces, Seibutsu-kogaku Kaishi, 79(12), pp. 463-469. Link

Prize for Medicine

Awarded to Donald Unger for investigating a possible cause of arthritis of the fingers, by diligently cracking the knuckles of his left hand — but never cracking the knuckles of his right hand — every day for more than sixty years.

Reference: Unger, D.L. (1998) Does Knuckle Cracking Lead to Arthritis of the Fingers?, Arthritis and Rheumatism, 41(5), pp. 949-950. doi: 10.1002/1529-0131(199805)41:5<949::AID-ART36>3.0.CO;2-3

Prize for Veterinary Medicine

Awarded to Catherine Douglas and Peter Rowlinson for showing that cows who have names give more milk than cows that are nameless.

Reference: Bertenshaw, C., Rowlinson, P. (2009) Exploring Stock Managers’ Perceptions of the Human-Animal Relationship on Dairy Farms and an Association with Milk Production, Anthrozoos, 22(1), pp. 56-59. doi: 10.2752/175303708X390473

Peace Prize

Awarded to Stephan Bolliger, Steffen Ross, Lars Oesterhelweg, Michael Thali and Beat Kneubuehl for determining — by experiment — whether it is better to be smashed over the head with a full bottle of beer or with an empty bottle.

Reference: Bollinger, S.A. et al (2008) Are Full or Empty Beer Bottles Sturdier and Does Their Fracture-Threshold Suffice to Break the Human Skull?, Journal of Forensic and Legal Medicine, 16(3), pp. 138-142. doi: 10.1016/j.jflm.2008.07.013

Prize for Public Health

Awarded to Elena Bodnar, Raphael Lee and Sandra Marijan for inventing a brassiere that, in an emergency, can be quickly converted into a pair of face masks, one for the brassiere wearer and one to be given to some needy bystander.

Reference: US Patent #7255627 for “Garment Device Convertible to One or More Facemasks.”


Dr Elena Bodnar demonstrates the face mask bra, assisted by (l-r) Wolfgang Ketterle (Nobel Prize in Physics, 2001), Orhan Pamuk (Nobel Prize in Literature, 2006) and Paul Krugman (Nobel Prize in Economics, 2008)