All Postings (91)


Subversive? Physics?

My Philosophy!

Scripts Beget Scripts


Theoretical Physics. A Hobby.

Self-Referential Poetry

Silent Online Writing

'Are You Still Doing PKI?'

My Philosophy (?)

Impact of physics on my life

Not much happened in 2015




Farewell Posting ...

Hacking away...

Web Project - Status

We Interrupt ...

Poetry from Poetry


Life and Work

Definition: 'Subversive'

2014 in Books

Physics Postings

Engineering Postings

True Expert


2014 - a Good Year

Physics or Engineering?

Engineering Links

What Is Art?



Google's Poetic Talents

Certificates and Heat Pumps

Nr. 5: A Mind-Altering Experience

Technet postings


Pink Spaceship

radices = Roots!

IT Postings

Web Projects

Life, the Universe, and Everything

Uh-oh, No Posting in March

PKI Resources

PKI Issues

Subversive Work

Spam Poetry

A Career 'in Science'


On the Shoulders of Subversive Giants

Search Term Poetry

Facebook Art

2013 in Books


Explain, Evaluate, Utilize


About Life-Form Elke Stangl

elkement and This Site

No. 3: Internet Apocalypso


Newsletter Resurrection


For Free

Subversive Yearly Report

Is My Life a Cliché?

Indulging in Cliché

Torture Turning Trivia

Intermittent Netizen

Knowledge Worker...


Physics on the Fringe

Graduation Speech

The Element is Back!


Physics Links


Not Funny

Calendar and Magic


In Need of a Deflector

About to Change

A Nerd's Awakening

For the Sake of Knowledge


Profession Or True Calling?

No. 2: On Self-Reference

I Have No Clue About Art



The End

No. 1: On Subversion at Large


Emergency Exit

Modern Networker


The Scary Part

Exploring the Work Space


Instead of a CV

Favorite Books


Elke was here

Blog Postings on Physics

(elkement. Last changed: 2015-11-07. Created: 2015-02-04. Tags: Physics, Thermodynamics, Quantum Physics, Quantum Field Theory, History Of Science. German Version.)

Today I am writing articles on physics mainly on my English (elkement's) blog and our German (punktwissen) blog. This site (and its precursor, help me with curating the links to my English physics postings.

All English postings written to date are displayed below, in decending order, from the Physics category's feed on my blog.

While I gravitated against quantum theory and the connection between physics and philosophy in 2012 and 2013, I finally switched to more hands-on applied physics in 2014. Before I have done 10-15 years of soul searching; some of these posts from 2012-2013 give prove of that.

'Physik - Urbanitzky', 1905

Spheres in a Space with Trillions of Dimensions (2017-06-17 19:55:10)
I don’t venture into speculative science writing – this is just about classical statistical mechanics; actually about a special mathematical aspect. It was one of the things I found particularly intriguing in my first encounters with statistical mechanics and thermodynamics …

You Never Know (2017-05-25 16:22:15)
… when obscure knowledge comes in handy! You can dismantle an old gutter without efforts, and without any special tools: Just by gently setting it into twisted motion, effectively applying ~1Hz torsion waves that would lead to fatigue break within …

Ploughing Through Theoretical Physics Textbooks Is Therapeutic (2017-05-07 11:16:21)
And finally science confirms it, in a sense. Again and again, I’ve harped on this pet theory of mine – on this blog and elsewhere on the web: At the peak of my immersion in the so-called corporate world, as …

Simulating Peak Ice (2017-05-02 08:43:17)
This year ice in the tank was finally melted between March 5 to March 10 – as ‘visual inspection’ showed. Level sensor Mr. Bubble was confused during the melting phase; thus it was an interesting exercise to compare simulations to …

Mr. Bubble Was Confused. A Cliffhanger. (2017-04-08 11:06:20)
This year we experienced a record-breaking January in Austria – the coldest since 30 years. Our heat pump system produced 14m3 of ice in the underground tank. The volume of ice is measured by Mr. Bubble, the winner of The …

Ice Storage Hierarchy of Needs (2017-02-22 17:30:10)
Data Kraken – the tentacled tangled pieces of software for data analysis – has a secret theoretical sibling, an older one: Before we built our heat source from a cellar, I developed numerical simulations of the future heat pump system. …

On Photovoltaic Generators and Scattering Cross Sections (2017-01-07 12:10:39)
Subtitle: Dimensional Analysis again. Our photovoltaic generator has about 5 kW rated ‘peak’ power – 18 panels with 265W each. Peak output power is obtained under so-called standard testing condition – 1 kWp (kilo Watt peak) is equivalent to: a panel …

Learning General Relativity (2016-12-03 18:54:45)
Math blogger Joseph Nebus does another A – Z series of posts, explaining technical terms in mathematics. He asked readers for their favorite pick of things to be covered in this series, and I came up with General Covariance. Which …

And Now for Something Completely Different: Rotation Heat Pump! (2016-11-03 09:55:35)
Heat pumps for space heating are all very similar: Refrigerant evaporates, pressure is increased by a scroll compressor, refrigerant condenses, pressure is reduced in an expansion value. *yawn* The question is: Can a compression heat pump be built in a …

Re-Visiting Carnot’s Theorem (2016-09-18 10:09:51)
The proof by contradiction used in physics textbooks is one of those arguments that appear surprising, then self-evident, then deceptive in its simplicity. You – or maybe only: I – cannot resist turning it over and over in your head …

Rowboats, Laser Pulses, and Heat Energy (Boring Title: Dimensional Analysis) (2016-03-01 11:25:33)
Dimensional analysis means to understand the essentials of a phenomenon in physics and to calculate characteristic numbers – without solving the underlying, often complex, differential equation. The theory of fluid dynamics is full of interesting dimensionless numbers –  Reynolds Number …

Temperature Waves and Geothermal Energy (2016-01-22 11:04:48)
Nearly all of renewable energy exploited today is, in a sense, solar energy. Photovoltaic cells convert solar radiation into electricity, solar thermal collectors heat hot water. Plants need solar power for photosynthesis, for ‘creating biomass’. The motion of water and …

Peter von Rittinger’s Steam Pump (AKA: The First Heat Pump) (2015-11-24 09:51:42)
Peter von Rittinger’s biography reads like a success story created by a Victorian novelist, and his invention was a text-book example of innovation triggered by scarcity ( Bio DE / EN). Born 1811, he was poor and became an orphan …

Heat Pump System Data: Three Seasons 2012 – 2015 (2015-09-29 17:23:33)
We have updated the documentation of monthly and seasonal measurement data – now including also the full season September 2014 to August 2015. The overall Seasonal Performance Factor was 4,4 – despite the slightly lower numbers in February and March, …

Lest We Forget the Pioneer: Ottokar Tumlirz and His Early Demo of the Coriolis Effect (2015-06-04 10:25:35)
Two years ago I wrote an article about The Myth of the Toilet Flush, comparing the angular rotation caused by the earth’s rotation to the typical rotation in experiments with garden hoses that make it easy to observe the Coriolis …

An Efficiency Greater Than 1? (2015-06-01 08:41:32)
No, my next project is not building a Perpetuum Mobile. Sometimes I mull upon definitions of performance indicators. It seems straight-forward that the efficiency of a wood log or oil burner is smaller than 1 – if combustion is not …

How to Evaluate a Heat Pump’s Performance? (2015-04-21 14:00:52)
The straight-forward way is to read off two energy values at the end of a period – day, month, or season: The electrical energy used by the heat pump and the heating energy delivered. The Seasonal Performance Factor (SPF) is …

Ice Storage Challenge: High Score! (2015-04-01 09:31:38)
Released from ice are brook and river By the quickening glance of the gracious Spring; The colors of hope to the valley cling, And weak old Winter himself must shiver, Withdrawn to the mountains, a crownless king. These are the …

“An Unprecedented Test for Europe’s Electricity System” (2015-02-27 15:56:31)
And we will not be able to contribute – by a hair. We have just ordered our photovoltaic generator, and installation is planned for April. It is the (partial) Solar Eclipse on March 20 that made Europe’s Transmission System Operators …

A Sublime Transition (2015-02-14 13:51:01)
Don’t expect anything philosophical or career-change-related. I am talking about water and its phase transition to ice because … …the fact that a process so common and important as water freezing is not fully resolved and understood, is astonishing. (Source) …

More Ice? Exploring Spacetime of Climate and Weather. (2015-01-28 14:58:07)
I have become obsessed with comparing climate data for different regions in the world and in different years (space + time). Finally I have found the tool I was looking for; now I can compare average Ice Days quickly – days …

“Being Creative with What Is Available” (2014-11-27 11:11:00)
This is a quote from Simon Dale’s website who has built several eco-friendly ‘Hobbit’ houses. It reminded me of the cave house built into lava bubbles by Lanzarote’s most famous artist César Manrique: Being creative with what is available has …

All Kinds of Turbines (2014-10-16 21:54:47)
Dave asked an interesting question, commenting on the heat-from-the-tunnel project: Has anyone considered the fact that the water can be used to first drive turbines and then distributed to supply the input source for the heat pumps? I am a …

Pumped Heat from the Tunnel (2014-10-04 14:04:17)
The idea to use a reservoir of water as a heat pump’s heat source is not new. But now and then somebody dares to do it again in a more spectacular way. Provided governmental agencies give you permit, lakes or …

What Learning about Feynman’s Path Integrals Was Good for (2014-07-03 14:08:07)
I have gone to great lengths on this blog in order to explain how and why a degree in physics prepares you for seemingly different careers, or at least does not hurt. But it would have been so simple. I …

Grim Reaper Does a Back-of-the-Envelope Calculation (2014-06-22 13:52:20)
I have a secondary super-villain identity. People on Google+ called me: Elke the Ripper or Master of the Scythe. [FAQ] No, I don’t lost a bet. We don’t have a lawn-mower by choice. Yes, we tried the alternatives including a reel …

How to Introduce Special Relativity (Historical Detour) (2014-02-26 12:14:35)
I am just reading the volume titled Waves in my favorite series of ancient textbooks on Theoretical Physics by German physics professor Wilhelm Macke. I tried to resist the urge to write about seemingly random fields of physics, and probably …

Non-Linear Art. (Should Actually Be: Random Thoughts on Fluid Dynamics) (2014-02-05 12:34:34)
In my favorite ancient classical mechanics textbook I found an unexpected statement. I think 1960s textbooks weren’t expected to be garnished with geek humor or philosophical references as much as seems to be the default today – therefore Feynman’s books …

In Praise of Textbooks with Tons of Formulas (or: The Joy of Firefighting) (2014-01-15 20:04:18)
I know. I am repeating myself. Maurice Barry has not only recommended Kahneman’s Thinking, Fast and Slow to me, but he also runs an interesting series of posts on his eLearning blog. These got mixed and entangled in my mind, …

This Year in Books: Biographies, Science, Essays. (2013-12-31 14:25:41)
This is my pick of books I enjoyed reading in 2013. I am hardly capable of reviewing books but I tend to pick books in order to answer a specific question. Biographies I have a penchant for physicists’ lives in the first …

“Student Friendly Quantum Field Theory” (2013-12-22 16:46:31)
As other authors of science blogs have pointed out: Most popular search terms are submitted by students. So I guess it is not the general public who is interested in: the theory of gyroscopes, (theory of) microwaves, (theory of) heat …

Using Social Media in Bursts. Is. Just. Normal. (2013-12-02 17:23:58)
I have seen lots of turkey pictures last week and this has reminded me of an anniversary: When I saw those last time I have just started using Twitter, Google+ and Facebook. @elkement Little bird has left its egg! #newbie …

Mastering Geometry is a Lost Art (2013-11-25 12:29:58)
I am trying to learn Quantum Field Theory the hard way: Alone and from text books. But there is something harder than the abstract math of advanced quantum physics: You can aim at comprehending ancient texts on physics. If you …

Revisiting the Enigma of the Intersecting Lines and That Pesky Triangle (2013-11-15 16:59:51)
Chances are I made a fool of myself when trying to solve an intriguing math/physics puzzle described in this post. I wanted to create a German version but found it needs a revision. I will just give you my stream …

Learning Physics, Metaphors, and Quantum Fields (2013-11-04 10:11:10)
In my series on Quantum Field Theory I wanted to document my own learning endeavors but it has turned into a meta-contemplation on the ‘explain-ability’ of theoretical physics. Initially I had been motivated by a comment David Tong made in his introductory lecture: …

Hyper-Jelly – Again. Why We Need Hyperspace – Even in Politics. (2013-10-17 10:40:56)
All of old. Nothing else ever. Ever tried. Ever failed. No matter. Try again. Fail again. Fail better. This is a quote from Worstward Ho by Samuel Beckett – a poem as impenetrable and opaque as my post on quantization. …

From ElKement: On The Relation Of Jurassic Park and Alien Jelly Flowing Through Hyperspace (2013-10-16 11:32:52)
Originally posted on

On the Relation of Jurassic Park and Alien Jelly Flowing through Hyperspace (2013-10-09 15:43:25)
Yes, this is a serious physics post – no. 3 in my series on Quantum Field Theory. I promised to explain what Quantization is. I will also argue – again – that classical mechanics is unjustly associated with pictures like …

May the Force Field Be with You: Primer on Quantum Mechanics and Why We Need Quantum Field Theory (2013-09-29 13:37:20)
As Feynman explains so eloquently – and yet in a refreshingly down-to-earth way – understanding and learning physics works like this: There are no true axioms, you can start from anywhere. Your physics knowledge is like a messy landscape, built …

On Science Communication (2013-09-23 13:38:27)
In a parallel universe I might work as a science communicator. Having completed my PhD in applied physics I wrote a bunch of job applications, one of them being a bit eccentric: I applied at the Austrian national public service …

From ElKement: Space Balls, Baywatch, and the Geekiness of Classical Mechanics (2013-09-19 13:06:51)
Originally posted on

Space Balls, Baywatch and the Geekiness of Classical Mechanics (2013-09-17 13:48:13)
This is the first post in my series about Quantum Field Theory. What a let-down: I will just discuss classical mechanics. There is a quantum mechanics, and in contrast there is good old classical, Newtonian mechanics. The latter is a limiting case …

And Now for Something Completely Different: Quantum Fields! (2013-09-11 19:50:41)
Do I miss assignments and exams? Definitely not, and I am now – finally, really, absolutely – determined to complete another program I had set for myself about 2-3 years ago. I had not been able to pull it off in addition …

Greatest Innovation Ever (2013-09-04 15:01:28)
I like Top Something Lists, in particular the hilarious variety. In a more serious state of mind I wondered what a list of the top inventions or top innovations of humankind might comprise. (Nitpickers, I don’t care about distinguishing ‘innovation’ …

Theory and Practice of Trying to Combine Physics with Anything (2013-06-03 18:30:17)
You have told me, you miss my physics posts. I have missed them, too, and I give it a try. But I cannot help turning this into a cross-over again, smashing together half-digested psychology, physics, IT networking, and badly hidden …

On Time Travelling: Rigorous Categorization of Science Fiction Movies (2013-04-20 11:07:40)
Do you remember the scary moment when Ashton Cutcher alias Evan recognizes suddenly that his arms are crippled – and that they have been crippled since many years? This is a scene from The Butterfly Effect: Evan discovers that he …

Philosophy Degrees are Undervalued (2013-04-07 11:31:34)
This is a vain and self-servicing reblog. I really like the figures in this post (as a physicist). As physics undergraduates we used to joke (black humor) about why in hell we are studying physics when the corporate world (the …

The Falling Slinky and Einstein’s Elevator (2013-04-03 22:24:43)
I have not known that this toy has a name at all. The ‘spring’ that can go down the stairs is called Slinky: We all know how the Slinky walks – but how does it fall? The following video might …

The Twisted Garden Hose and the Myth of the Toilet Flush (2013-03-17 18:03:09)
If you have wrapped your head around why and how the U-shaped tube in the flow meter (described in my previous post) is twisted by the Coriolis force – here is a video of a simple experiment brought to my attention …

Intuition and the Magic of the Gyroscope – Reloaded (2013-03-13 21:50:17)
I am baffled by the fact that my article The Spinning Gyroscope and Intuition in Physics is the top article on this blog so far. So I believe I owe you, dear readers, an update. In the previous article I have …

Physics / Math Puzzle: Where Is the Center of Mass? (2013-02-09 19:23:31)
On randomly searching for physics puzzles I have come across QuantumBoffin‘s site. The puzzle is about how to determine the center of mass of a body using the plumb line method, given there is some uncertainty due to experimental errors: You have …

Random Thoughts on Temperature and Intuition in Thermodynamics (2013-01-28 12:43:56)
Recent we felt a disturbance of the force: It has been demonstrated that the absolute temperature of a real system can be pushed to negative values. The interesting underlying question is: What is temperature really? Temperature seems to be an intuitive everyday …

The Strangest Man (2013-01-27 12:52:53)
Originally posted on

Trading in IT Security for Heat Pumps? Seriously? (2013-01-22 18:45:21)
Astute analysts of science, technology and the world at large noticed that my resume reads like a character from The Big Bang Theory. After all, an important tag used with this blog is cliché, and I am dead serious about theory and …

Why Fat Particles Radiate Less (2013-01-06 22:29:41)
I am just reading Knocking on Heaven’s Door by Lisa Randall which has a chapter on the impressive machinery of Large Hadron Collider. The LHC has been built to smash proton beams against each other: Protons, not electrons. Why protons? I stumbled upon the …

Joule, Thomson, and the birth of big science (2013-01-03 13:09:47)
Originally posted on

Quantum Field Theory or: It’s More Than a Marble Turned into a Wiggly Line (2012-12-30 12:47:10)
I had been trained as an experimental physicist which meant I was good at locating vacuum leaks, adjusting lasers and lenses, telling reasonable data from artefacts, and being the only person that ever replenished the paper feed of the X-ray diffractometer (Yes, at …

The First Heat Pump Ever Was Built in Austria (2012-12-10 17:46:49)
I have confessed recently that I am from Austria. So the patriot in me wants to entertain her readers with the story of a milestone in the history of engineering thermodynamics – set by an Austrian! The development of the …

Is It Determinism if We Can Calculate Probabilities Exactly? (2012-12-05 19:19:04)
I set a stretch goal for myself: I want to force myself to keep some posts of mine short. As a fan of MinutePhysics I am launching a new category: Physics in a Nutshell. I am going to try to tackle a question …

The Dark Side Was Strong in Me (2012-11-26 19:05:50)
Once in a communication skills training I learned: For each of us there is a topic / a question / a phrase that will turn us raging mad or leave us in despair, or both. The point the trainer wanted to …

Are We All Newtonians? (2012-11-20 10:11:02)
In my most recent posts I showed off: 1) Sandra Bullock killing a computer virus and ordering pizza online, 2) a cartoon making fun of all academic disciplines I refer to this blog, 3) images of cute furry animals – dead and …

Microwave Ovens Are Not Rodent-Ready (2012-11-16 10:24:52)
It happened again.  It took me four years to cope with, and now I have to start again from day zero. (Insert 2 minutes of silence and grieving here) Any device we use on a daily basis is designed for safety. …

Physicist, Philosopher, and Engineer (2012-11-12 09:26:40)
The headline indicates that I am going to tell one of this old jokes: A physicist, a philosopher and an engineer meet … This is in fact correct, but in an extremely subtle way. As the title of this blog …

Einstein and His Patents (2012-11-02 10:50:43)
No, this is not about Einstein’s achievements as a moonlighting scientific paradigm shifter, while working as a patent examiner in his day job. Einstein is famous for the theories of special and general relativity, and for the correct explanation of the photoelectric effect …

111 Years: A Shining Example of Sustainable Product Development? (2012-10-23 23:51:12)
The centennial light bulb has celebrated its 110th birthday last year and the story has percolated the web. According to its web cam the bulb is still alive. This light bulb has caused quite a stir when featured in the documentary on planned obsolescence: The Light Bulb Conspiracy. …

Physics Paradoxers and Outsiders (2012-10-04 18:55:21)
As I did – plain and straightforward – normal science, I do not consider to develop my personal Theory of Everything or to build my personal perpetuum mobile. I am pretty conservative with respect to the laws of thermodynamics and just understanding the …

Reconcile All This (Goals of This Blog) (2012-09-30 13:00:12)
I have now blogged since more than half a year and I have pseudo-blogged since about 10 years, but I have never stated any goals explicitly. Also fuelled by my Website Resurrection Project (and e.g. the related resurrection of notes on …

I Did Normal Science (2012-09-21 10:29:22)
Finally I am reading one of the most influential books on science: Thomas Kuhn – The Structure of Scientific Resolutions. I should have done so earlier, actually the book should be part of any science major’s undergraduate curriculum. Naive as …

The Spinning Gyroscope and Intuition in Physics (2012-09-05 17:55:56)
If we would set this spinning top into motion, it would not fall, even if its axis would not be oriented perpendicular to the floor. Instead, its axis would change its orientation slowly. The spinning motion seems to stabilize the gyroscope, …

Sniffing the Path (On the Fascination of Classical Mechanics) (2012-08-30 13:18:17)
Newton’s law has been superseded by relativity and quantum mechanics, and our universe is strange and compelling from a philosophical perspective. Classical Mechanics is dull. I do not believe that. The fundamentals of Newtonian Mechanics can be represented in a …

Unification of Two Phenomena Well Known (2012-08-12 13:46:34)
Unification is a key word that invokes some associations: The Grand Unified Theory and Einstein’s unsuccessful quest for it, of course the detection of the Higgs boson and the confirmation of the validity of the Standard Model of Particle Physics, or Kepler’s Harmonices Mundi. …

Why Do Heat Pumps Pump Energy so Easily? (2012-05-10 14:22:28)
I know my posts are usually walls of text, but I am trying to improve! In his landmark physics course, the Feynman Lectures on Physics, Richard Feynman tries to explain what an explanation in physics actually is. You can always understand …

Stupid Questions and So-Called Intuition (2012-04-29 12:21:09)
At the very beginning of my career I organized a meeting of a research project team, still an undergraduate. The project was concerned with the development of thin films for microwave circuits, and my task in the project was the optimization of those films. …

Anatomy of a Decision (1) (2012-04-11 22:41:38)
About a year ago I have taken a decision and I am now taking a leap of faith. This blog is gravitating about this decision and I am writing now about a journey that began a while back. I am …

I neither Met Newton nor Einstein (2012-03-28 11:23:54)
I am just reading The Trouble with Physics by Lee Smolin. I am not familiar with string theory, quantum gravity and the related communities, so I cannot comment on Smolin’s main statement. But there is a section in the last …

Real Physicists Do Not Read Popular Science Books (2012-03-25 12:09:39)
At least this is what I believed for quite a while. Now I think I was wrong – not only for the reason that also real scientists might enjoy light entertainment or simply stay informed about the science communication activities …

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