Tag: physics

Gently Rotting Away

GOd, how I hate to have a cold. Especially when I have a week off and the weather is nice – now, at the beginning of November, we have the golden & warm days one expects in “golden October”, or Indian summer. I feel weak and start to feel cold when I go to the letterbox … So I did not yet take care for my radio, maybe tomorrow, but I took some pictures of stuff I found.
There was a time, possibly in the late eighties or the nineties or so, when we used to buy and use compact disks like … I don’t know. All of a sudden they were everywhere, cheap and affordable, used for storage, send around, replacing what was before them, the floppy disks, the short-lived zip-thingy. CDs came in small boxes or on a spindle. And while clearing out my stuff here I found one of these old spindles with some cds still on it. This object must be at least fifteen years old. The cds were never used, they simply aged. The spindle was not kept in the dark, but also not intentionally put into the sunlight, it just lingered on, as such things sometimes do.


Dusty CD-Spindle-Box Seen From Above
Dusty CD-Spindle-Box Seen From Above


I think the plastic thing once was transparent. If one removes it, this is what you see :


Reddish-Brown CD On Top
First CD On Top, Reddish-Brown


The CD on top – there are seven in total – did clearly change colour. I have not put it into a cd-drive, hence can not say whether it is usable. The whole thing is put on a normal, run-of-the-mill white paper as it is used in uncountable numbers in the bureaus of the world. I did not take care for the colours to be corrected & rectified, this is just meant to give you an impression.
Here you see six of the seven cds (I did not unpack the last one), in their succession as they were on saied spindle.


All CDs, sharp


Here is a different version, just the flash-setting changed ; a little longer exposure, hence not sharp.


ALL CDs, not so sharp


The second is golden-yellow over the whole surface, while numbers three & four only start to stain darkly from the outside inwards, as does the first TDK. Interestingly the two remaining cds, the one seen on the right down and the one not shown (directly under this one), have changed their surfaces uniformly, without a major yellow strip on the outside, the same way the second “Soennecken” did.
So … if you have boxes of compact disks with photographs and other data stored, never looked after, ach – was soll denn schon passieren ? What can happen is that your cds are gently rotting away. A safety copy now & then could be a good idea. And if you are at it, try whether you can still open the files with your actual programs, there was also  some change over the years.


Comet 1744

The comet of 1744 (Ger., Eng.) must have been a remarkable celestial spectacle; up to six tails have been visible, the whole show lasted for some months. (Go here and here for lists of appearances of comets from the 15th to the 18th century, see the links that lead to illustrations.) A side effect of the comet’s appearance was that Martin KNUTZEN (1713-1751) (Ger., Eng., ADB) was shot to scientific stardom. At least in Königsberg (Ger., Eng., today).
KNUTZEN was teaching philosophy and mathesis (mathematics, physics) at the university of Königsberg, following NEWTON’s ideas. In 1738 KNUTZEN had predicted that a comet that had appeared in 1698, would show up again in 1744. This was basically totally wrong, as the great mathematicus Leonhard EULER (1707-1783) (Ger., Eng.) criticised in a letter to GOLDBACH (1690-1764) (Ger., Eng., ADB) an 23rd of June 1744:

“He seriously thinks that this comet has a tempus periodicum of 45 3/4 years, because he saw from the catalogus Hevelianus (Ger., Eng.) that nearly always after this intervall a comet appears. He believes that the one seen 1652 is identical with the one from 1698: Exploring the matter closer one finds that scarcely two comets can be found that are more different than these two.”

KNUTZEN’s short shot to fame is inasmuch more important as he was a teacher of young Immanuel KANT (1724-1804 (Ger., Eng.), who studied  at the university since 1740. KANT’s first important book, Allgemeine Naturgeschichte und Theorie des Himmels (Ger., Eng. – which by the way is not written in 1755 as the wiki-articles state, but published! – is surely not un-influenced by all the events of 1744. KNUTZEN did not accept KANT’s work in 1746 as dissertation and young Immanuel went through the home-tutor hell in the East-Prussian province for eight years; at least this enabled him to own undisturbed study and – notably the last position in the family of Count Keyserling – helped to shape his manners and allowed him access to the higher society.
In his book KANT tried to structure the world of the fixed stars, the most important impact gave him Thomas WRIGHT’s (1711-1781 (Ger., Eng.) An Original Theory or New Hypothesis of the Universe from 1750. WRIGHT explains the look of the milky way as “an optical effect due to our immersion in what locally approximates to a flat layer of stars.” The stars of the milky way are on one level in disk shape rotating around a center – all the distant nebulae are rotating disk-shaped galaxies too. They form a super-system of galaxies rotating around one center – KANT goes further and thinks that there are several super-systems. The analogy between the local solar system and higher cosmical systems works only – according to KANT – when the permanent movement of the systems as a whole is accepted: Ohne die “fliehenden Kräften” würden alle “Weltsysteme” “über kurz oder lang in einen Klumpen zusammenfallen”. Without centrifugal forces all world systems would sooner or later collapse in one clump. It will take another hundred years until Friedrich Wilhelm BESSEL (1784-1846) (Ger., Eng.) shows that the fixed stars have a motion of their own.
KANT changes the idea of space and explains the origin of it all from the basic material forces, attraction and repulsion. It is no static cosmos, the creation of solar systems and galaxies is not the end of the development, the end of the creation – in fact there is no creator God, but an ongoing periodic process of chaos and new start. And of course mankind is no singularity: “Indessen sind doch die meisten unter den Planeten gewiß bewohnt, und die es nicht sind, werden es dereinst werden.” Roughly: “Most of the planets are surely inhabited, and those which are not yet surely will.” The world is not in the center anymore, and is no exception: The Vernunft believes in a universe of inhabitable worlds and reasonable beings. Hans BLUMENBERG (1920-1996) (Ger., Eng. here) has reformulated the sky’s ambiguity KANT mentions in the Kritik der praktischen Vernunft (Ger., Eng. Text): The sight of the sky annihilates our importance by its sheer largeness, but at the same time it forces us by its sheer emptiness to take nothing else serious but ourselves.

KANT’s publisher went bancerott while the book was printed, it was delivered too late for the spring book fair in Leipzig, and thus went nearly unnoticed by the public, neither LAMBERT (1728-1777) (Ger., Eng.) nor LAPLACE (1749-1827) (Ger., Eng.) knew it.

See also: Weigl, Engelhard: Schauplätze der deutschen Aufklärung. Ein Städterundgang, Reinbek 1997


This morning, Tuesday the 30th of March at 9:00, in the CERN (in a nutshell) a very interesting experiment will take place. You can watch it here. I will definitely have a look over a cup of coffe, I suppose there will not be much to see, except for some excited eggheads. But the small possibility that one or two “Black Holes” will turn up is given, also a Higgs-particle or “boson” is expected to appear. If it goes wrong the world disintegrates, but the worst case is that nothing changes. So let’s see and have coffe. Or tea.