13 June 2010

The Einstein Tower – Hobbit Astrophysical Observatory in Germany

If the denizens of The Shire had ever pursued sciences such as astrophysics or astronomy, then their observatory may well have look something like this.  The Einstein Tower in the German town of Potsdam looks like something a curious Halfling might visit to explore the skies above Middle Earth but is, in fact, a perfect example of early twentieth century expressionist architecture – of the human variety. However, just like that of the Shire, its history has not always been a peaceful one.

The idea for the Einstein Tower (or Einsteinturm in German) came about in 1917 and was funded and built through public donation.  It went in to operation in 1924 three years after Einstein won the Nobel Prize for Theoretical Physics and at a time when Germany was in social upheaval.

It was designed by the architect Eric Mendelsohn (seen on the left in 1931) who at the time was among the most prolific of the modern architects working in Europe at the time.  In Germany he was far better known than his contemporaries but his reputation has since been eclipsed by the likes of Le Corbusier and Van Der Rohe. We will return to Mendelsohn later, but for now let us return to one of his finest works.

Potsdam can be found twenty five kilometers to the south west of the German capital, Berlin and the Einstein Tower is perched on the summit of the town’s largest hill, the Telegraphenberg.  It is a relatively small tower but it is vigorously modeled.  Mendelsohn’s idea was that it would symbolize the greatness of Einsteinian concepts but remain a functional building.  The tower temporarily lost its name in 1933 when the Nazis took over Germany and it was heavily damaged during the Second World War.
Mendelsohn sought a building of complete plasticity in his design, a building without angles but with round and smoothed corners. Concrete is the ideal for this, as it can be forced to curve but at the time of building there was a shortage of the material and parts of the building were built from brick.  However, this combination of concrete and brick worked as the external effect was produced by rendering the surface material of stucco.  It is still viewed by many as one of the most uniquely brilliant buildings of the twentieth century.

Einstein’s Tower houses a magnificent solar telescope which was designed by the astronomer Erwin Finlay-Freundlich who was also a working associate of the great man Einstein himself. Below shows the inside the dome of the Einsteinturm - on the right is the heliostat, on the left, a mirror which reflects the beam of light down the tower.

Legend has it that Mendelsohn took Einstein on a tour of the tower and waited patiently for the nod of approval from the world famous scientist.  And waited.  And waited.  Much later when Einstein met with the building committee it is said he whispered a single word – organic.  To this day it is not known if this utterance was intended as approval or opprobrium.

One of the great ironies of this amazing building was that it enriched the lives of German citizenry at the time.  Yet the three men associated with it at the time, Finlay-Freundlich, Mendelsohn and Einstein all had to leave Germany in the 1930s because of their Jewish ancestry.  The bust of Einstein in the tower was reported to have been melted down during the Nazi era but after the end of the war in 1945 it was established that it had been hidden by workers at the tower.  The building was itself heavily damaged by allied bombing and had to be renovated, something that was undertaken again when during the celebrations of its 75th birthday in 1999.

Initial research at the Einsteinturm revolved around the 1911 General Theory of Relativity.  A predicted effect of the theory was a small shift of spectral lines in the gravitational field of the sun.  Known today as red shift, the Einsteinturm was designed to verify this phenomenon.  It soon became obvious that this was going to be a lot more difficult than previously thought because other solar influences obscured the shift of spectral lines.  So, the outer solar atmosphere and its behavior soon became the primary focus of the Einstein Tower.  Red shift was subsequently not proven until the 1950s. Solar Magnetic Fields and their behavior is the current focus at the Einstein Tower.

Most people know what happened to Einstein – he went to live and work in the USA.  What of the other two men, Mendelsohn and Finlay-Freundlich?  Both had to leave Germany because of the rampant anti-semitism of the thirties.  So what happened to them?  Mendelsohn (left) fled to the UK in 1933 and eventually went on to the USA.

There, among other things he helped the US Army build German Village.  This was a replica of working class housing estates which helped the Americans gain the necessary knowledge to firebomb the real thing in to acquiescence in 1944 and 5.  He died in 1953 having spent the remainder of his life on projects for Jewish communities.

What of Finlay-Freundlich (left)? He too was obliged to leave Germany in 1933 and he first went to Turkey where he worked at the University of Istanbul as a professor.  Following that he went to St Andrews in Scotland and then on to John Napier as professor of Astronomy.  In 1953 he proposed (with Max Born) an explanation of red shift.

The original function of the Einstein Tower had, by one of its instigators, finally been realized.