30 JAN 2015 by ideonexus
Barcodes in Nature
I have used the barcode as a
symbol of precise analysis, in all its beauty. Mixed light is sorted into its
rainbow of component colours and everybody sees beauty. That is a first
analysis. Closer detail reveals fine lines and a new elegance, the elegance
of detection, of the bringing of order and understanding. Fraunhofer
barcodes speak to us of the exact elemental nature of distant stars. A
precisely measured pattern of stripes is a coded message from across the
parsecs. There is grace in th... 1 
notes
notes30 JAN 2015 by ideonexus
The Brain Making Sense of an Orchestra
But our unconscious feats of unweaving and weaving are greater even
than this. Think what is happening when you listen to a whole orchestra.
Imagine that, superimposed on a hundred instruments, your neighbour
in the concert is whispering learned music criticism in your ear, others
are coughing and, lamentably, somebody behind you is rustling a
chocolate wrapper. All these sounds, simultaneously, are vibrating your
eardrum and they are summed into a single, very complicated wriggling
wave of p... 1 notes
notes22 MAR 2012 by ideonexus
Decibel Scale is Logarithmic, Like the Richter Scale
In fact, a physics colleague, Mark Srednicki of U.C. Santa Barbara, brought to my attention a much greater gaffe in one episode, in which sound waves are used as a weapon against an orbiting ship. As if that weren't bad enough, the sound waves are said to reach “18 to the 12th power decibels.” What makes this particularly grate on the ear of a physicist is that the decibel scale is a logarithmic scale, like the Richter scale. This means that the number of decibels already represents a power o... 1 notes
notesKrauss describing a particularly egregious science-blunder in an episode of Star Trek.
22 MAR 2012 by ideonexus
The Bell Jar
A famous experiment in high school physics involves putting an electric buzzer in a bell jar, a glass container from which the air can be removed by a pump. When the air is removed, the sound of the buzzer disappears. As early as the seventeenth century, it was recognized that sound needed some medium to travel in. In a vacuum, such as exists inside the bell jar, there is nothing to carry the sound waves, so you don't hear the buzzer inside. To be more specific, sound is a pressure wave, or d... 1 notes
notesA jar with a buzzer placed inside it from which the air is pumped out, eliminating the sound.
21 JUL 2011 by ideonexus
Sound Localization
One trick our brains use to figure out the location of a sound is to compare the time it takes to reach each ear. For example, sound waves emanating from a wind chime located to your right will reach your right ear a few milliseconds earlier than they reach your left ear, and the brain uses this small timing difference to compute exactly how far to your right the chime is located. Researchers have capitalized on this timing difference to test sound localization, using a special experimental t... 1 notes
notesHow the brain localizes the origin of a sound by calculating the difference in time between the soundwaves hitting one ear versus the other.
08 JUL 2011 by ideonexus
Nature VS Nurture in Child Development
When a three-month-old, a one-year-old, and a four-year-old look at the same event, they seem to have very different thoughts about it. They seem to transform the light waves and sound waves into different representations, and they use different rules to manipulate those representations. Children don't have just a single, fixed program that gets from input to output. Instead, they seem to switch spontaneously from using one program to using another, more powerful program. That makes babies an... 1 notes
notesAre babies programmed to go through their cognitive developments or are they the natural result of their reaching a certain critical mass of understanding?
08 JUL 2011 by ideonexus
Psychological VS Mechanical Causality in Infant Understan...
As scientists we think that everything is mediated by physical causality of some sort, including our interactions with other people. There are, in fact, light and sound waves that go from one person to another even if we can't see them with the naked eye. But from our everyday point of view, it appears we are able to influence people without any direct physical contact at all. (It's probably that fact that makes telepathy seem plausible to so many people.) After all, just looking at someone a... 1 notes
notesBabies learn the differences between psychological and physical causality, before this they tend to make the mistake of using psychological means to influence the physical world... Magical thinking in adults may be a holdover of this habit.
