I have been blogging 'seriously' about physics since 2012. My motivation has been a blend of jotting down notes on interesting things I've just found, conveying my decades-old fascination with some phenomena, trying my hands at popular science writing, and reporting on my own research.
Today I am asking myself - did I learn anything from that on a meta level? To read myself, I am re-arranging the list of my physics posts and sort them by topic and sub-topic. The list says it all, I think.
I wanted to write about quantum mechanics, but it seems I was always most intrigued by classical mechanics, statistical mechanics, and thermodynamics. The latter has become my true home in physics - which has come as a surprise to myself. Yes, thermodynamics is my specialization, but years ago I rather figured that this is my job, and I rather want to follow the latest news on quantum information and particle theory in my spare time. It turned out that I am more interested in history of physics and in the evolution of concepts that are now 'well known'.
My recurring meta-topic is that classical mechanics / thermo can be as interesting, 'geeky' if you wish, mathematically 'weird', and surprising as fields that seem to be more popular.
This list may remain a static snapshot. I am editing the chronological list of my physics posts here on the blog. This list might lseem to lack some of my more applied / engineering postings, re our heat pump system and data. These are here.
Thermodynamics and Statistical Mechanics
Concepts and foundations
Random Thoughts on Temperature and Intuition in Thermodynamics
Time evolution of systems in phase space: On the Relation of Jurassic Park and Alien Jelly Flowing through Hyperspace.
Phase-space in depth: Hyper-Jelly – Again. Why We Need Hyperspace – Even in Politics.
Carnot’s efficiency, irreversibility, proof by contradiction, paradoxes: Re-Visiting Carnot’s Theorem.
Mathematics used in statistical mechanics: Spheres in a Space with Trillions of Dimensions.
Heat pump basics
Brief explanation, absolute temperature:
Why Do Heat Pumps Pump Energy so Easily?
Coefficient of Performance of a heat pump: An Efficiency Greater Than 1?
Cross-check of numbers for a large heat pump system: Pumped Heat from the Tunnel
COP versus Performance Factor: How to Evaluate a Heat Pump’s Performance?
Energy accounting, economics: Heat Pump System Data: Three Seasons 2012 – 2015.
Heat conduction, diffusivity, latent heat:
Storage Challenge: High Score!
Heat conduction, heat equation: Temperature Waves and Geothermal Energy.
Heat diffusion length: Rowboats, Laser Pulses, and Heat Energy (Boring Title: Dimensional Analysis).
Simple version, daily energy balances:
More Ice? Exploring Spacetime of Climate and Weather.
Heat transport, energy balances. Simulations versus simple energy accounting: Ice Storage Hierarchy of Needs.
Detailed version: Heat exchangers, heat equation, 1-minute time slots: Simulating Peak Ice.
Thermodynamics and energy basics, dimensional analysis
kW and kWh.
No, You Cannot ‘Power Your Home’ by One Hour of Cycling Daily.
Phase transitions, ideal gas law (pressure sensor) Mr. Bubble Was Confused. A Cliffhanger.
kWp, power, energy, energy flow: On Photovoltaic Generators and Scattering Cross Sections.
History and inventions
Einstein’s Refrigerator and other inventions:
Einstein and His Patents
Centennial light bulb, sustainability: 111 Years: A Shining Example of Sustainable Product Development?
Checking 19th century papers: Peter von Rittinger’s Steam Pump (AKA: The First Heat Pump).
Phase transitions of water, Mpemba effect: A Sublime Transition.
By an Austrian start-up – pressure gradient created by centrifugal forces: And Now for Something Completely Different: Rotation Heat Pump!
(I realize that some of my articles in the 'engineering' category would also qualify for this sub-category History. For example: I wrote a - less detailed - post on Rittinger's steam pump before. But part of the fun with these list is that you have to take those hard decisions of tagging ...)
Classical Mechanics and Fluid Dynamics
Equations of motion and Lagrangian formalism
Principle of Least Action.
Sniffing the Path (On the Fascination of Classical Mechanics)
Equation of motion, intuition in physics: Are We All Newtonians?
Motion of a falling slinky spring: The Falling Slinky and Einstein’s Elevator.
Principle of Least Action, again – extended version: Space Balls, Baywatch and the Geekiness of Classical Mechanics.
From Newton’s Law to Navier-Stokes Equations: Non-Linear Art. (Should Actually Be: Random Thoughts on Fluid Dynamics).
Estimates related to the physics of scything:
Grim Reaper Does a Back-of-the-Envelope Calculation.
Back-of-the-envelope cross-checks, hydro power: All Kinds of Turbines.
Torque, forces, precession, nutation.
The Spinning Gyroscope and Intuition in Physics.
Another way to explain how the gyroscope works: Intuition and the Magic of the Gyroscope
Coriolis force (1): The Twisted Garden Hose and the Myth of the Toilet Flush:
Coriolis force (2). Lest We Forget the Pioneer: Ottokar Tumlirz and His Early Demo of the Coriolis Effect.
Physics and geometry
My first (later corrected) proposal of a solution:
Physics / Math Puzzle: Where Is the Center of Mass?
Correcting my earlier proposal: Revisiting the Enigma of the Intersecting Lines and That Pesky Triangle.
Newton’s geometrical proof of Kepler’s laws: Mastering Geometry is a Lost Art.
Quantum Mechanics and Quantum Field Theory
Interpretations of quantum mechanics:
Is It Determinism if We Can Calculate Probabilities Exactly?
Quantum Mechanics versus QFT: Quantum Field Theory or: It’s More Than a Marble Turned into a Wiggly Line.
Started a series: And Now for Something Completely Different: Quantum Fields!
Summary on QM: May the Force Field Be with You: Primer on Quantum Mechanics and Why We Need Quantum Field Theory
Quantization – starting from statistical mechanics: On the Relation of Jurassic Park and Alien Jelly Flowing through Hyperspace.
Path integrals and symmetries: Learning Physics, Metaphors, and Quantum Fields.
Book review: Student Friendly Quantum Field Theory.
Electromagnetism and special relativity
Unification of Two Phenomena Well Known.
Charged particles lose energy when accelerating: Why Fat Particles Radiate Less.
An alternative way of understanding SR: How to Introduce Special Relativity (Historical Detour).
List of resources: Learning General Relativity.
Using physics-like methods in economics and sociology
Networking theory, instabilities:
Theory and Practice of Trying to Combine Physics with Anything
E-Mails and communications: Using Social Media in Bursts. Is. Just. Normal.
‘Philosophical’: Learning physics, culture
On trying to explain physics without math:
Real Physicists Do Not Read Popular Science Books
Re The Trouble with Physics by Lee Smoli:. I neither Met Newton nor Einstein
On learning physics. Stupid Questions and So-Called Intuition.
Re Margaret Wertheim’s Physics on the Fringe Physics Paradoxers and Outsiders.
Physics as Therapy (1) In Praise of Textbooks with Tons of Formulas (or: The Joy of Firefighting).
Physics as Therapy (2) Ploughing Through Theoretical Physics Textbooks Is Therapeutic.
Today I am writing articles on physics mainly on my English (elkement's) blog and our German (punktwissen) blog. This site (and its precursor, radices.net) 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.
Heat pump usage in different countries and history of heat pumps
- Swedish Ground Source Heat Pump Case Study (2010), by GNS Science (New Zealand based consultancy)
- History of heat pumps - Swiss contributions and interntional milestones, by Martin Zogg, Process and Energy Engineering
Unusual heat sources
- Aquifer at Oslo Airport
- (Former) Cisterns - a paper documenting research done in Iowa in 1993. I have also summarized the paper in this blog post.
Sizing heat pumps - I am trying to learn the terminology of standards commonly applied in English-speaking countries:
Power grid and availability
- March 20 (2015) Solar Eclipse - a challenge for European Transmission System Operators: Announcement by ENTSO-E, Analysis by US-based company, success story. Electricity production in Germany (select week 12 of 2015) - the dip in March 20 is visible.
- Squirrels a major issue for the power infrastructure of the US: Squirrel Power!
- #DarkNL - outage in Newfoundland and Labrador, Canada in January 2014.
Hydro power plants
In Sweden the world's largest pumped hydro storage plant might be built:
- See bottom of page 30 of
this research paper:
Besides the official estimations there are some discussions [28b] about building pumping capacity between the lakes Vänern and Vättern in Southern Sweden. The difference in altitude is 44 meters between these lakes.?
- ... and the
last page of this presentation:
Possible future? Mariestads Kraftverks AB & others 50 km tunnel between the lakes Vänern & Vättern Cost: 250 billion SEK. Installed capacity: 50000 MW .
Free long-term weather data
Inputdaten für eigene Simulationen.
Germany and Austria.
- FTP server of the German weather service. Extensive and detailed datan, e.g. ambient air temperatures, for some locations since 1950!
- Annals by ZAMG - Austrian national weather service. Daily averages since 1994 as CSV files (only if you pick the link for German readers. The EN version still links to data in the older HTML format that requires you to run a browser in compatibility mode.
- Climate data for the last decades. The navigation is something you need to get used to (Pick: Cities, Climate, Climate Robot...). Therefore I start with Ice Days for Vienna. It is a bit weird that available data seem to depend on the choice of the language (less data for Vienna in English).
The winter 1962/63 was the coldest since 250 years in Europe (German article:
Winter 1962/63 in Europa. Englisch article:
Winter of 1962–63 in the United Kingdom).
More data from a talk / slides avaiable at the website of the Royal Meteorological Society: The bitter winter of 1962/63 - this winter was unusually mild in Canada and Greenland (p.17)
Could such a winter ever happen again? "The 1963 winter is well within the population of other cold winters that have been experienced in this country ... It is not necessary therefore to seek some very special cause in order to explain it." – H.C. Shellard , Meteorological Magazine , 1968 (p.21 of PDF)
Different heating systems
Statistics for Austria: Heating 2003 to 2012 by fuels used and heating system (in Austria). Less than 15% of (primary) heating systems are stoves, and they have been on a decline in the last decade.
Units, heat values, energy costs
Tools for converting units
- Heizwerte von festen, flüssigen und gasförmigen Brennstoffen auf Wikipedia.
- Heat values of different varieties of wood, per cord.
- Energy Content in Common Energy Sources (engineeringtoolbox.com)
Properties of water (for comparing the energy stored in a water / ice tank)
- Interesting properties of water as per Wikipedia: Specific heat, density.
- Thermal properties of water (engineeringtoolbox.com)
Costs of energy - international
- Photovoltaic systems are more expensive in the US than in Germany (2014), despite prices have dropped.
- Comparion of costs of kWh electrical energy worldwide. Costs seem to be much lower in the US and in Canada than in German. This article about the details of a typical US electrical bill implies that there are delivery fees on top of energy fees. On the other hand, the value for Germany seems to include anything.
Monitoring, Control, IT
Metering and monitoring electrical power consumption
- Smart meters with data loggers and/or various interface for attaching
loggers - to be installed behind the official smart meter:
- EMU Professional, different types available with different interfaces such as M-Bus, Modbus TCP and RTU, HTTP, included logger.
- Specification of the EMU meter's Modbus RTU interface.
- EM Series by B-Control / TQ-Systems (The SMA Smart Meter is an OEM meter of that type): EM210 has a web server for online monitoring and stores log files, EM300 supports real-time logging via Modbus RTU, Modbus TCP and a simple HTTP interface (but does not store log files, and uses the web server for configuration only).
- Parsing an online monitoring website is perhaps the most universal 'real-time protocol' in case not other interfaces are available. E.g. by using Powershell, I tested with the local website of a Fronius Symo inverter and their web portal www.solarweb.com. One option: Start an InternetExplorer.Application comobject and identify the html containing the interesting value per its ID (getElementById).
Manuals of data loggers by Technische Alternative Gmbh (for control units UVR1611, UVR16x2)
- C.M.I - Control and Monitoring Interface
- BL-NET Bootloader
- Logging with CMI and BL-NET on the same CAN bus in parallel is not supported.
- Bus topology. Note that UVR1611 is automatically terminated by default.
Heating with computers
Computers installed in private homes provide their computing power to cloud services - while heating those homes.
- Paper presented at the conference Hotcloud 2011: The Data Furnace: Heating Up with Cloud Computing.
- A prototype based on a similar idea, in need of crowdfunding, 2015: Project Exergy wants to build a home computer that also heats your house.
Basics (Physics) - Mechanics, Electrodynamics
The Feynman Lectures of Physics