# Fotoeins Fotografie

## My Vienna: 30 days of spring from the 6

Danube morning: photo by Christian Stemper, courtesy of Wien Tourismus (no.50401).

With this entry’s appearance, I’m on the other side of the world, 8500 kilometres away.

I dashed in and out of Vienna a handful of times between 2001 and 2003 when I lived in Heidelberg; but I have no visual records of that period in time. I’ve returned to Austria’s capital city for the first time since 2018. I wondered then how a stay in the Mariahilf, the city’s 6th district, would go.

That time is now, because I’m spending a month in the 6.

To minimize weight, I’m experimenting:
•   32-L backpack as the 1 and only piece of (carry-on) luggage, and
•   “no bricks no heavy glass”, but a compact mirrorless Fuji X70 camera.

The apartment location and neighbourhood are ideal. I’m within easy reach of the city’s U-Bahn, surrounded by the U3, U4, and U6 metro lines. I’ve already located a drugstore and several grocery stores, all inside a trivial 0.5 km (0.3 mi) walk. I’ve also been told I’ll have many Viennese coffees and several meals in the area.

There’s a lot to pursue, see, and do; and there’s no time to waste.

## Fotoeins Friday at Uni Vienna: Ludwig Boltzmann

I’ve highlighted notable physicists who’ve been memorialized within the Arcade Courtyard in the main building of the University of Vienna:

2 Apr: Lise Meitner;
9 Apr: Christian Doppler, Erwin Schrödinger;
16 Apr: Joseph Littrow, Karl Littrow;
23 Apr: Josef Stefan;
30 Apr: Ludwig Boltzmann.

These are all names whose work and discovery form the historical and scientific basis of my university education in the field of physics.

The inscription for physicist and university professor Ludwig Boltzmann reads:

Ludwig Boltzmann, 1844-1906:
Professor of mathematics, 1873-1876;
Professor of theoretical physics, 1894-1900 and 1902-1906.

Buried in Vienna’s Central Cemetery, Boltzmannn’s gravestone includes the equation for entropy in statistical mechanics and thermodynamics.

$S \,=\, k \log W$

In collaboration with Josef Stefan, the Stefan-Boltzmann Law describes how an object that absorbs all radiation falling on its surface emits radiative intensity (I, radiation energy per unit time per unit area) that’s proportional to the fourth power in temperature T with constant emissivity ε (between 0 and 1) and Stefan-Boltzmann constant σ.

$I \,=\, \epsilon \sigma T^4$

Ludwig Boltzmann was also one of Lise Meitner’s professors and advisors at the university. Meitner would become the 3rd woman to receive a doctorate in physics from the University of Vienna, and would go on to describe the process of nuclear fission.

The university’s historical main building is inside the city’s Old Town which has been inscribed as UNESCO World Heritage Site since 2001. I made the photo above on 16 May 2018 with a Fujifilm X70 fixed-lens prime and the following settings: 1/30-sec, f/5.6, ISO1000, and 18.5mm focal length (28mm full-frame equivalent). This post appears on Fotoeins Fotografie at fotoeins DOT com as https://wp.me/p1BIdT-iGz.

## Fotoeins Friday at Uni Vienna: Josef Stefan

Throughout the month, I’m highlighting notable physicists who’ve been memorialized within the Arcade Courtyard in the main building of the University of Vienna:

2 Apr: Lise Meitner;
9 Apr: Christian Doppler, Erwin Schrödinger;
16 Apr: Joseph Littrow, Karl Littrow;
23 Apr: Josef Stefan;
30 Apr: Ludwig Boltzmann.

These are all names whose work and discovery form the historical and scientific basis of my university education in the field of physics.

The memorial to Josef Stefan (Jožef Štefan) includes a small inscription:

Josef Stefan
Professor of physics, 1863-1893
Born 1835, died 1893

An important physics equation is the Stefan-Boltzmann Law, which describes how an object that absorbs all radiation falling on its surface emits radiative intensity I (radiation energy per unit time per unit area) that is proportional to the fourth power in temperature T; the other two quantities are constants: emissivity ε between 0 and 1, and the Stefan-Boltzmann constant σ:

$I \,=\, \epsilon \sigma T^4$

Both Stefan and Boltzmann are buried in Vienna’s Central Cemetery. Boltzmann’s gravestone includes his entropy equation. Stefan does not have his own grave; instead, his descendants in the Munk family have a gravestone.

The university’s historical main building is inside the city’s Old Town which has been inscribed as UNESCO World Heritage Site since 2001. I made the photo above on 16 May 2018 with a Fujifilm X70 fixed-lens prime and the following settings: 1/60-sec, f/3.2, ISO1000, and 18.5mm focal length (28mm full-frame equivalent). This post appears on Fotoeins Fotografie at fotoeins DOT com as https://wp.me/p1BIdT-iGt.

## Fotoeins Friday at Uni Vienna: Joseph & Karl Littrow

Throughout the month, I’m highlighting notable physicists who’ve been memorialized within the Arcade Courtyard in the main building of the University of Vienna:

2 Apr: Lise Meitner;
9 Apr: Christian Doppler, Erwin Schrödinger;
16 Apr: Joseph Littrow, Karl Littrow;
23 Apr: Josef Stefan;
30 Apr: Ludwig Boltzmann.

These are all names whose work and discovery form the historical and scientific basis of my university education in the field of physics.

A wall plaque memorializes astronomers Joseph Littrow and (his son) Karl Littrow at left and right, respectively. Joseph was director of the Vienna Observatory from 1819 to 1842; Karl succeeded his father as director from 1842 to 1877.

The Littrow crater on the Moon is named after Joseph, but he’s also best known in physics for his optics inventions: the Littrow prism and the Littrow configuration optimizing the performance of a spectrograph with a specially designed diffraction grating.

The university’s historical main building is inside the city’s Old Town which has been inscribed as UNESCO World Heritage Site since 2001. I made the photo above on 16 May 2018 with a Fujifilm X70 fixed-lens prime and the following settings: 1/30-sec, f/2.8, ISO1000, and 18.5mm focal length (28mm full-frame equivalent). This post appears on Fotoeins Fotografie at fotoeins DOT com as https://wp.me/p1BIdT-iGr.

## Fotoeins Friday at Uni Vienna: Doppler & Schrödinger

This month I’m highlighting notable physicists who’ve been memorialized within the Arcade Courtyard in the main building of the University of Vienna:

2 Apr: Lise Meitner;
9 Apr: Christian Doppler, Erwin Schrödinger;
16 Apr: Joseph Littrow, Karl Littrow;
23 Apr: Josef Stefan;
30 Apr: Ludwig Boltzmann.

These are names whose work and discovery form part of the historical and scientific basis of my university education in the field of physics.

Shown in the image are memorials to Christian Doppler and Erwin Schrödinger at left and right, respectively. My translation to the inscription on the Doppler memorial inscription reads:

Christian Doppler, 1803-1853:
Professor of physics at Vienna University, 1850-1853.
The Doppler principle has ensured the Doppler name for all time.

With his birth house in Salzburg as backdrop, I briefly describe the physics of the Doppler effect.

The Schrödinger memorial highlights an early 20th-century revolution in science in the form of quantum mechanics: the physics of the atom and its constituents. The well-known equation representing Newton’s 2nd Law, “F = ma”, is to classical mechanics, as the following equation is to quantum mechanics.

$i \hbar \dot{\psi} \,=\, H \psi$

I was able to “localize” the final resting place for Schrödinger and his wife in the Austrian alpine town of Alpbach. The above equation appears on the their grave in Alpbach and on the memorial at the University of Vienna. The equation is a generalized form of the time-dependent Schrödinger equation describing a physical system, represented by ψ, which changes with time.

The university’s historical main building is inside the city’s Old Town which has been inscribed as UNESCO World Heritage Site since 2001. I made the photo above on 16 May 2018 with a Fujifilm X70 fixed-lens prime and the following settings: 1/60-sec, f/6.4, ISO1000, and 18.5mm focal length (28mm full-frame equivalent). This post appears on Fotoeins Fotografie at fotoeins DOT com as https://wp.me/p1BIdT-iGo.