Some Words About Physics, Python And The World In General

Simple, Complicated, Complex

Central to my area of research are many things that are called complex. Complexity science and complex networks for example. For this reason I have become quite aware of the meaning of the word and therefor of its misuses. So I thought I try to explain what complex means in relation to simple and complicated and why it is so important to understand the difference in the modern world - I am really tempted to write complex modern world but it is kind of unfair to write about explaining a word and then use it without having explained it.


So when are things simple? Sure enough one can use simple do describe many things. However there is a more or less good definition of what simple is in the context of complexity. Simple relationships between two things are those that one can easily understand, the ones that are obvious. One might say linear speaking in a more mathematical context. However I believe it is better to stay with the more vague definition of easy to understand and obvious. These might change from person to person but that only makes it clear that there is no clean border line between simple and complicated.


Complicated is in many ways the opposite of simple. This may sound impossible, since where is the place then for complex - but hear me out. Complicated things are those that we can not understand easily, that take time to think through. Some of the complicated problems are so hard that it might take years to understand them, but it is possible. Complicated problems are hard because they usually don‘t conform to our what we now about the world so far or because the chain of how one thing becomes another thing is much longer then we are used to.


Now that we have both of these words covered we can start to make some examples. Lets have a look at a car. Using a car seems fairly simple, at least in concept. Doing it in the real world takes some time to get used to but everyone can do it. Back to the concept however. In the simplest version you have two pedals and a steering wheel. You push one pedal to accelerate and one to decelerate, while you use the steering wheel to point the car in the right direction. Simple. Even if you have a manual and have to operate a clutch and a stick it is still easy enough to understand. If you look however how the acceleration part really works you will soon find out that it is not so simple. In modern cars it starts with a sensor that measure how far you pressed the pedal. This signal then gets processed by the ECU. Depending on the state of the car, it‘s speed, acceleration, steering angle, possible faults and diverse settings, the state of the environment like the temperature, oxygen in the air and legal requirements (hello VW scandal) the ECU then decides what to do. It does that by feeding all the data it gathers in to a software model of the physical engine it controls. This software model then computes how much fuel and which time to inject in the engine. And so on. Depending in the model of car you can go down this rabbit hole at least a few more miles deep until you hit rock bottom. At several points there will be things that are not happening the way one would expect them to be assuming things are generally simple. However given enough time, we can understand all parts of this process and they will enable us to understand how the car accelerates if we press the gas pedal down.

Engineering, Politics And How To Save The World

When you ask yourself or others to make a list containing the big problems that mankind is facing, you will probably find these among them:

Note that this is an unordered list, so the position has no specific meaning. Many of these problems are tied very closely together for example: hunger and lack of clean water are often due to poverty which is often caused by the lack of education, terrorism/war and or disasters. However the point of this post is to convince you that most of these problems are technically already solved we only lack the political willpower or solution to implement the solution.

Technically Solved

Lets have a look at the overpopulation and hunger complex. Both seem to be closely linked in peoples minds. We are to many, the world can not feed so many people. At the same time we waste almost as much food in the world as is consumed in Africa (222 million tonnes wasted vs. 230 million tonnes consumed). We do not have a food production issue we have a food distribution issue combined with a quality of production issue in some developing countries. Considering that most of the food is produced and wasted in the developed countries however, mainly a distribution issue. This however means we have technically solved food production. The problem then must be poverty, if the people would have enough money they could buy the food.

So what about poverty?

Poverty is so apparent because of the distribution of wealth, the richest 1% of the people now own about 50% of the world. And the rest of the distribution is similarly unjust. As demonstrated by the hunger problem, it is not really the case that we do not have enough for everybody, we just do not know how to give it to everybody. Our attempts to do so have so far failed and ended in totalitarianism instead of communism. Please note, this is no attempt to make any claims that capitalism is inherently bad. I believe quite the opposite, that is, that capitalism has brought as very far – to where we are now – but we still need to evolve it. Nevertheless, we have plenty of ideas of how to fix the problems we have currently in capitalism. There are proposals to change the current money and banking regime and change taxation in ways to keep the rich from owning 50% of the world. Tackling these fundamentals of capitalism, money and property seems impossible (at least without pitchforks). Yet there are numerous example where it has been done before, our money regime changed last in 1971 due to decisions made by the U.S. government. After it was only introduced in the 1940. An example for seemingly impossible taxation can be found in post war Germany where the actual wealth of a people was taxed. It was officially planed as means of to redistribute wealth. And we are not speaking about small amounts: up to 50% of a persons wealth could be redistributed spread over 30 years. Imagine that. One might think that this was only possible due to Germany‘s isolated position after the war. However the law was based on a Finnish law and Finland was not at all isolated after the war. So again the conclusion could be that we technically know how to solve the problems of capitalism but we just can not implement them politically. Anyhow, wealth distribution is certainly not the only cause of poverty.

What about war and terrorism?

This is one of the things I really struggle with. Is there a technical solution to war? For many cases there actual might be one, however other conflicts seem impossible to resolve. Will the Palestinians stop to hate the Israelis once their economic situation is better? Would the Israelis allow the situation to become better? Will this end the terror? Impossible to answer. We know that there are basically no wars in modern day and age that lead to an economically better situation, so one might assume that there are no wars in capitalism but this is obviously not true. Never the less, the number of people involved in wars is on an historic low (video), so maybe capitalism is also winning on this front. Terrorism however seems to be another shoe. It seems to be the case the the western world constantly looses its battle against terrorism and the more wars we fight the more terrorists we create. And since the modern terrorism is basically founded as an answer against the wars the US and its allies are fighting in the middle east this should not surprise anyone. In other words, terrorism is the evolutionary answer to war. We can not win against it with war. However there are plenty of ideas of how to fight against it, which again we do not implement because we can not bring it on politically. So lets look at some other fields. (Note: I should link to something about this, however I don‘t feel like I have proper sources. A lot of my thinking however is based on ideas from this awesome podcast)


There is no doubt that diseases are a problem – admittedly one I do not know much about. I know we have a problem with a shrinking number of effective antibiotics. I have seen how quickly a virus can get out of control (Ebola) and how infectious mutations (SARS/MERS) can be. However we have also seen how quickly we actually can develop a vaccination and discover even new classes of antibiotics or mechanisms of defeating harmful bacteria. So the real question might be why did we not manage to develop these things before a serious crisis was around the corner. The answer is most of the time given in the form of capitalism: it is usually not effective for a company to develop a treatment that heals quickly. If you develop a new antibiotic drug it will be given to the patient for 1-2 weeks an that is it. A vaccine is even worse, a one time shot. If you develop a new pain medication, a new cancer or depression treatment you will likely make profit from the same patient for years. You can just not sell an antibiotic so expansive that it has the same return of investment. So where do you invest your money? This makes the pharmacy industry look like bad people when in fact they are only doing the same as every other business. However we have plenty of ways to influence what the big industries are doing, it all comes down to the right incentives – as it always does in capitalism. You want to keep your patents for your most grossing drug for two years longer? No problem develop something that helps against on of the things on this list we update yearly and you can! Who can implement such a thing? Right, politicians. So what about the other big problem...

Climate Change / Availability Of Energy

This is a problem where we definitely do not have the technical solution yet right? Why in the world would everybody be working on a solutions otherwise? Wrong. I wrote at this at length in a previous post. In review: you could harvest all the energy the world needs in a 500 km square in Africa. One would need to build thermo solar power plants, which would feed the power to methane production plants. The methane production needs CO2 and Water as input. The CO2 can be taken from the air and the water might be gathered through desalinization of ocean water. The compressed methane can then be shipped or pipelined in the world to be used like conventional natural gas. Most of the infrastructure is already there, as are natural gas powered cars, buses, heating systems and power plants. The solar plants, desalination plants and even the methane plants already exist. Just to make this clear, this is not a partial solution. If implemented this will be a CO2 neutral way of supplying the world with easy to store and transport energy until the sun burns out. This could put an end to climate change. At least to further damage. Anyway, it is obviously not about to happen. Instead we have climate conference after climate conference no end insight. We also develop all kinds of fancy plans and complex infrastructure to solve it. So again, the problem is technically solved we just can not implement it politically.

But The Most Important Problem Is … !

I am more or less doing research in the energy sector. Therefore I usually argue like this: Availability of (cheap) energy is the most important problem we need to solve because it will solve all other problems. All we do is consuming energy, all things that make our life easier are consuming energy. We want everyone to have clean drinking water, no problem if we have cheap and "clean" energy we can just build a wastewater treatment plant or a desalination plant. We need more food? No problem we just build a greenhouse, temperature and light controlled and we are good. War? Mostly due to oil nowadays, once we need no oil anymore: gone. Disease? Once people do not need to care about oil and war they have more time to work on disease prevention … and so on. And you will find a lot of other very clever people arguing the same way for energy. Or for war, or poverty, or hunger …  In fact all of these problems are somehow connected, you can not solve one without the other. This does not mean that there is one root problem connecting them, they are all real problems on their own. However the connection between most of them is politics …

So Should We All Become Politicians Then?

Definitely not. While there are some former scientist in politics, some even from natural sciences, I believe not all of us are suited for a job in politics. However most researchers should radically change the view on how to do research. There is one part of science which is tasked with finding out new things about nature, sometimes very fundamental things like the particles that make up the universe, sometimes more about tiny details like how two very specific molecules interact. The another part of science however is tasked with finding solutions, often to the problems discussed here or related ones, or even completely unrelated ones. There might not always be a clear distinction between these roles and the same researcher or group may switch between both of them rapidly. However most of the time it is very clear if the outcome is a solution to a problem or a new fact about "how things work". Now every time you develop a solution to something you have to consider the politics that might be needed to implement your technical solution – because if your solution is political not possible to implement it is just not a solution. For other fields this kind of thinking has become very common, every time a new engineering solution is developed someone will check if it is cost-efficient. From the engineering standpoint this is not necessary if it technically works, the problem is solved right? Except it isn‘t because if it is not a profitable solution for a company it will not be adopted. The same is true if the solution is not feasible in a socio-political sense. Therefore in the same way engineering and many other disciplines have adopted economic theory we need to adopt socio-political thinking to test if our solutions are actual solutions to a problem not just technical ones. In many ways this means to just adopt more from economic theory than just cost calculations, because at the core economics deals with the incentives people have for making their decisions, it just happens to be the case that incentives often come in the form of money. Nevertheless incentives and rules are what politicians can use to make a difference, however very few technical solutions we have come with a bundle of incentives and rules that need to be in place in order for the solution to work right.


To give a more concrete example, we just saw the introduction of distributed energy storage for the mass market. However the battery technology is not yet cheap enough or good enough to go off grid. But since we have a lot of solar and wind energy in certain countries, resulting in high price fluctuations for power, these batteries start to make economic sense in a way that they can be cost effective. Which is why we will most probably see them adopted in many places. Once we have enough batteries they will however begin to influence the price of electricity, because they dampen the price fluctuation we currently see, by buying power when it is cheap and selling it when it is expensive. Which means once we have enough batteries the fluctuations will reduce considerably if not vanish, which is very beneficial for society because it means energy is always available in enough magnitude. We have to remember however that these very fluctuations are what made the batteries worth buying in the first place. Economic theory now suggest that people will stop buying batteries because it is no longer profitable. The problem however is that the cost effectiveness of the batteries was calculated over many years, so once at the point that the price fluctuations begin to shrink, it is already to late for all the buyers of batteries. Economic theory again suggest that we all try to optimize our profit, how could you do that if you have bought a battery? Fairly easy, you just try to sell as late as possible when the price starts to rise, because as long as no one is selling the price will continue to rise. So there is now an incentive and a possibility in place for all the battery owners to increase the fluctuations instead of decreasing them. There are several reasons why you can not play this waiting game indefinitely, first of all at some point the grid will have a blackout. Second, the regulated power plants will kick in and supply the power needed. Third, if enough of the other players sell before you, you will not make your needed profit. While the third reason might keep the whole situation in check, by keeping everyone on its toes while waiting, it does by no means guarantee stability. Because now everyone is looking for a change in the speed of the rising price, because a slower rising price suggest the others have begun to sell. So now a slowdown might trigger an avalanche of sales, flooding the market. So instead what we need is a regulations that makes it very unlikely or downright impossible for the owners of batteries to engage in this kind of speculation, while still giving them an incentive to buy a battery helping to stabilize the power grid. It is exactly this kind of political solution that is needed for the technologies to succeed and be of value for all of society. We engineers are problem solvers, however we leave some of the toughest problems to figure out for the politicians – even though we know they fail to solve them a lot of the times. This has to change.

Random Thoughts About The Future - Cars

TL;DR: I believe we overestimate the capabilities of battery driven cars and ignore other possibilities, such as fuel cells or grid connected vehicles.

Since my master thesis is now finished, I have some more time for other things. There are several things I plan to write about, including my thesis itself. One topic that gets a lot of coverage without really going in depth is the future of cars. In many ways Germany is the land of cars: We have the fastest roads. We not only build a lot of cars (Volkswagen is almost the biggest car manufacturer), but we also build the high end ones, which everyone desires (say BMW, Audi and Mercedes). Furthermore, a lot of jobs in Germany depend on the automobile industry, some say every seventh, but in reality it’s probably not that much.

In a recent discussion someone told me that it is impossible that the big German carmakers do not have a plan for the future – they must have because it is their job. I argued that it was not the big mainframe companies who prospered through the PC age and not the big phone manufacturers that build our smartphones to day – so why should the carmakers of today deliver the transportation of tomorrow?

What the transportation of the future will look like is the key question. In other words we have to ask: What job does the car for us and what job has a new the techology to do, when oil gets too expensive to burn. This question does not get asked enough. We only try to replace what we have with something similar; instead of making or at least dreaming about something that is better suited to do its job. Or as Henry Ford said: "If I had asked people what they wanted, they would have said faster horses." What most companies do at the moment is, take a car with a combustion engine and put a battery pack and an electric motor in it – seems like a “faster” horse to me. On the other hand, the first car, built by Gottlieb Daimler in Germany, was pretty much a horse wagon with a combustion engine.

The car enables us to get from A to B whenever we want, with almost all the luggage we desire and virtually no matter where A and B are. It does that, with a reasonable price per distance, a reasonable price per car and with adequate speed. Furthermore, a car is easy enough to drive, anyone can learn. You can go faster via a small plane, but you lose a lot of the flexibility and flying is much more expensive. Plus you will need years to learn how to fly. On the other end of the spectrum is public transport. To go by bus or train is usually cheaper, but you again lose a lot of flexibility, however, you do not have to learn anything. Well, except how to navigate the overly complex ticket vending machine. Carrying a lot of luggage is more exhausting because you not only have to get it to the next bus stop or train station, but you also usually have to move it several times between different lines.

One thing we tend to forget is, that we only can travel that easily by car because of the entire infrastructure that we build around it. First of all we have roads everywhere. Sometimes this seems so normal that we tend to take it as given. Imagine if we somehow came to the conclusion that we would use planes for every longer distance trip, so that there would be no road network between cities, no motorway and no interstate. The world would look very different then. Secondly there is a very dense network of gas stations, car dealerships and car workshops that support our cars. There are some places in the world where you do not have such infrastructure, like in parts of Siberia. In such places driving suddenly becomes a much harder undertaking, involves much more planning and gets a lot slower.

In reality there are two parts that make up the car experience if you will: the car itself and the infrastructure. We tend to see trains as very limited, because you need to build railway lines everywhere to use them – but that is exactly what we did for cars. You could argue that a road is much more versatile than a railway lines and that we as mankind used roads long before the car was invented. But how many cars modern cars can you drive for long distances on the roads of the middle ages?

But let‘s focus again on the vision of the electric car, its shortcomings and possible solutions, which I think are overlooked a lot of the time. The idea of the electric car is really old and simple: you combine chemical electricity storage with an electric motor, put that in the body of a standard car and you are ready to go. What you get is a car that drives silently, has a lot of torque and needs a lot less mechanical parts. It is even simpler to drive than a car with combustion engine because you don‘t need a clutch or gearbox. There is one severe problem though: energy density.

Energy density means: How much energy one can store (and then easily release) in proportion to the weight of a certain system. In a lithium ion battery you can store about 0.5 MJ per kg while one kilogram of gasoline can release about 43 MJ. It is much harder to put the energy back into the gasoline than into the lithium ion battery though. In other words you need about 80 kg of battery system to replace one kg of gasoline. This results in heavier cars, because the loss of mechanical components does not compensate the weight. In fact accumulators are so heavy that you cannot pack enough of them into one car to get the same mileage as in a gasoline car. The famous Tesla Model S weighs 2.1 tons and can drive up to 480 km. A comparable Audi A6 or Mercedes E class weighs between 1.6 and 2.0 tons and has a total mileage of up to 1000 km. Even though the whole system in the electric car is much more efficient – it can transform a higher percentage of the stored energy into movement (or kinetic energy) – does not help. This is the energy density problem. We will discuss it in the next few paragraphs.

There are some more problems coupled with it. Refilling a fuel tank is easy and reasonably fast, but charging a battery instead takes much more time and in the case of li-ion accumulators is rather complex. This becomes especially problematic when you want to drive a distance longer than it is possible with one charge. One solution is to replace the whole battery pack with a new charged one. Tesla Motors demonstrated that this is a technically feasible solution but it may have some economical problems because batteries age. But that is only a problem for the business model. Tesla could track the usage of every battery a driver uses and charge him accordingly. The Question might be if this would kill the price advantage of the electric car. If you look at the cost of "fuel" (a better term might be energy) per kilometre the electric car can easily win. You need about 20 kWh (Tesla Model S) per 100 km which will cost you about 5€, in comparison you will need at least 6 L fuel per 100 km for a price of about 9€. But if these costs suddenly include the compensation for the aging battery, it does not look so bright anymore. A new battery will set you back about 10.000 € and will last 200.000 km, again these numbers are from Tesla, for 100 km this means 5€ for the battery.

A minor problem is that eclectric motors work so much more efficiently than combustion engines that there is not enough heat for heating the passenger cabin and since the energy you carry in your battery is very limited you are unwilling to spend any of that for heating. Driving in the winter, time will be even worse than now.

A much bigger problem with electric cars seems to be that they are not only expensive, but in addition to that the process of making them does not appear to scale (get cheaper with mass production). This is because a lot of the minerals used to build the batteries are in short supply and will become more expensive if demand rises. The next problem might be where the energy to charge all the electric cars should come from if we abandon oil and coal, but we will ignore this one for now.

While electric cars still can transport us from A to B they limit the distance between A and B. Aside from that; they seems to be and to remain expensive.

One solution may be, to make private transportation public, via car sharing. Anytime you need a car, you just grab one from the next sharing point and drive where you want to drive. If your destination is further away than the reach of the car, you just stop by a sharing point along the way and grab another one. While this is a very good solution for big cities and a lot of everyday driving, it mostly ignores problems with large amounts of luggage. How many times do you want to repack your car on the family vacation trip? How many times a day would a traveling businessman or salesman want to change his car? Even though we are talking about cars, imagine the same system for trucks – almost impossible.

Let‘s not forget another fact: not all people live in big cities. Even with rising costs of transportation in the future this will probably not happen. Depending on the country, the urbanisation might be on different levels, but even in the highly developed countries you still have 9% (Japan) up to 40% (Portugal, Greece, Ireland) of the population living in rural areas. How well can car sharing work for them? What if a shared car becomes stranded in a small village? How do you share a car if you need it every day? The solution of the shared electrical car seams worse here than what we already have.

One way to solve the energy density problem is to make cars independent of energy transportation – you just connect them to the grid. Just like an electric train or a trolleybus. There are even ideas to transfer energy wirelessly via induction. Imagine you are driveing on a motorway; your car connects to the overhead wire and switches into autopilot, to charge its battery and take over driving for you while doing so. You can lean back and take a nap. The combination of connection to the power grid and the autopilot are actually separate things, but they fit very well together. You do not want to manually connect to the power line and whilst trying to overtake someone forget to unlock your connection first.

The ability to connect a car to the power grid for long trips would mean we could downsize the battery pack to last only for 100 km, with a small reserve for cold days. This would be sufficient for a shopping trip even if the next city is a bit further away. This would lower the cost of the car dramatically. We could even switch to other battery technologies (apart from lithium ion) that are much cheaper and widely available. The technology for pantographs (connection to the overhead wire) is also common and established. The obvious question is: what about the entire new infrastructure? We will need new infrastructure anyway; the question is what will be the best investment?

Let‘s not end the discussion of infrastructure here. If we consider building a network of filling stations either for hydrogen or for battery charging/exchanging versus some kind of system to connect cars to the grid on the highway, the big difference is who is going to finance it. A network of filling stations can be built by numerous companies as long as a standard connector for filling is established. The grid connection system instead will probably have to be founded by the state. My personal standpoint is that infrastructure should be provided by the state, like roads, water supply, electricity and telephone/internet connection, but your mileage may vary. Maybe a government-run project to build new infrastructure as a beginning of a new century and to overcome the current crisis is not such a bad idea.

The possibilities of cars that can drive on their own is another, not so distant, future prospect that I believe is overlooked a lot of the time. Some of us view driving as a fun activity, like as it would be a small adventure every time, or even a race – and for sure there are times when driving is fun. Most of the time however we do not feel any kind of fun when driving to the supermarket though the rush-hour, or when we drive home from work like we do every day, or when we drive several hundred kilometres with a fully loaded vehicle to arrive at the beach even more stressed and ready for a holiday than when the trip begun. For all those times a self-driving car would be marvelous – just get in, set the destination, and lean back. That would be much more joy than the cars we have today. A car that is able to navigate and drive on its own would even allow for a better shared car experience. Just tell your service provider when you need a car and it will be in front of your door.

Another solution for the energy density problem is to just not exit the era of liquid fuels. The usage of fuel cells in cars made a lot of noise in the early 2000s, but since then it seems that nothing has happened on the hydrogen front. The contrary is true. Toyota as well as Nissan, Honda and Mercedes-Benz have continued development of fuel cell cars and plan to release them to mass market in 2014/15. The cost of manufacturing is still higher than for a normal car (about 20%) but this is nothing unusual for a new technology. The Toyota fuel cell prototype FCHV was already available for leasing in Japan.

The good news is that liquid hydrogen can store even more energy than gasoline, which translates to fuel cell cars that have a total mileage of about 800 km, like we used to get from fuel. The problem with liquid hydrogen is that it will not stay liquid so easily - in fact hydrogen will not stay where you want it to be in any form easily. Hydrogen at normal pressure and room temperature is a gas. In contrast to a battery with a fixed energy density, you can compress or liquefy a gas to raise its energy density. You need either a very low temperature to make it liquid or high pressure to store hydrogen in a form that is dense enough to be competitive. Since it is not easy to keep things at low temperatures, the only feasible way to store hydrogen in a car is in a very high-pressure tank (700 bar). This is because hydrogen atoms are so small that they tend to leave a normal the tank very easily right through it‘s walls. With a combination of several synthetic materials it is possible to reduce these diffusions to an acceptable level, so we can mark this problem as solved. The fuel cell cars weigh only about 100 kg more than their combustion engine counterparts and use the same amount of platinum in there fuel cell than a normal car in its catalytic converter. Sounds perfect right? All we need is a network of hydrogen refill stations and we are set.

The production of the pressurised hydrogen though uses a lot of energy. To fill a tank with hydrogen at a pressure of 700 bar you need the energy of 12% of the hydrogen you fill in the tank. That means you not only need the energy to produce the hydrogen, you need 12% more to store it. But once again we come back to the question of energy later.

Another possibility is to produce synthetic oil. That may sound strange but the qualities of oil as energy storage are so good that a lot of people are working on projects to produce cheap oil without drilling for it in the ground. One way is to grow special algae that can be used as fuel. There are several different approaches, but until now it does not seem like they will be successful in the near future. Nevertheless it might be part of the solution to keep cars with combustion engines around and fuel them with synthetic oil produced from algae.

What about combustion engines anyway? They are probably not completely going away but with rising prices for fuel they will become more of a hobby. We do not use sailing ships for transport anymore but there are still a lot of people who use them just for fun. The same can be said for horse-drawn carriages and so on.

A more utopian version for the energy density problem could look like this: You have to travel to a bigger city, say it is 500 km away, you have a lot of luggage and the trip has to start tomorrow. You pull your smartphone out of your pocket and type in your destination and the time you plan to start. Your phone will suggest an appropriate route on a car train and book your car. The next morning the car is waiting in front of your door. When you have finished loading you, or your car, drives to the next train station several kilometers away. The car train leaves every hour, your smartphone knew that and suggestet a time early enough to catch it. Once your train has reached its destination town your car will drive you to the address you entered yesterday. That way your car will need a much smaller battery, same as in the grid connection example. We already have the technology to integrate different means of transportation like that. The question is if something like this will be fast enough compared to traveling by car and whether it can deliver enough throughput for the big routes. It will need even more new infrastructure.

Now you might expect some words about the question of where the energy to power electric cars might come from. When I started writing about this so many thoughts crossed my mind that I decided they should go in another article.

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