10 March 2012

Much ado about nothing

"In the beginning there was nothing. God said, 'Let there be light!' And there was light. There was still nothing, but you could see it a whole lot better."
Ellen DeGeneres, (attributed)

"God made everything out of nothing, but the nothingness shows through."
Paul Valery (1871 - 1945)

"There is still a difference between something and nothing, but it is purely geometrical and there is nothing behind the geometry."
Martin Gardner (1914 - 2010),

What comes into mind when you think of the solar system? A collection of planets of different colours and textures, all displayed together on one page? Or perhaps one to each page?

Last year, Mishka Henner produced his "Astronomical," a publication which represents a scale model of the solar system. The sun fills most of pages 1 and 2. Jupiter and Saturn are quite small on their respective pages. The other planets are not much more than dots. But what impresses you most are the other pages. Page after page of nothingness, representing the true distance between the objects we recognise. The entire publication consists of 12 volumes, each of 506 pages. That's a total of over 6000 pages, of which all are plain black apart from the 12 that show the sun, planets and asteroid belt. An awful lot of nothing.

An online version of the same idea can be viewed at www.phrenopolis.com/perspective/solarsystem/
The sun fills most of the screen and the planets lie to its right. As you scroll, you are lucky if you don't miss the tiny spots that are the other planets before you arrive at Pluto on the extreme right. The author claims that the page is over half a mile wide.

Another version, rather larger in scale, can be seen at
www.phrenopolis.com/perspective/index.php

But what about the other end of the scale? The atoms that the planets, including ours, are made of contain protons and electrons. If the mass represented by the proton of a hydrogen atom were to be represented by a circle 1cm across, the electron would be about half a kilometre away. (see Visionlearning). However, when it comes to atoms, things aren't really as simple to understand as this. Nevertheless, there's still an awful lot of nothing.

For further discussion, see Physics Forums discussions
"Atoms are 'nothing but' space versus 'mostly' space"
and
"If all the empty space of atoms were removed, how big would this earth be?".

"Man is equally incapable of seeing the nothingness from which he emerges and the infinity in which he is engulfed."
Blaise Pascal (1623 - 1662)


Bending ice spike

Regarding my last post, thanks to Professor Erlend M. Schulsen of the Thayer School of Engineering at Dartmouth, New Hampshire, US, for his explanation as to why the ice spike bent:

"As to why the spike bent in time--the plastic hinge: You have here a superb example of creep deformation, also known as viscous flow --think molasses. Under its own weight, warm ice (and your ice undoubtably was at a temperature close to its melting point, if not right at the melting point) deforms plastically in a time-dependent or viscous manner. Temperate glaciers do the same thing, although more slowly. The action in your case occurred more quickly because the driving stress acting on the load-bearing area (i.e, on the most narrow part of the waist)was probably much higher than that acting on ice within a glacier, amplified by the bending of the spike. Indeed, creeping seems not the right word here. Running, perhaps?"