ForumsWEPRPhilosophical aspects of the laws of Thermodynamics

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Ok, granted, the title needs a bit more work But hey, since you are here, please don't leave! I promise it's not a science thread or anything, you need no specific background to take part in this discussion


I've been recently studying thermodynamics a bit more extensively and a lot of the aspects in thermodynamic systems that we want to increase (or decrease) revolve around the system's efficiency per the first and second law.

The efficiency of a system per the first law of thermodynamics is, very roughly, the system's net work (in a general sense, its output) and how much is that, compared to the same system's input. This leads to a percentage which could be described as

η = net work (system's output) / Q (or system's input).

This is all in terms of energy and it is only true for systems in which the output is more important than the input (cooling systems withdraw heat from the environment so it gets a little different) but either way it describes the same physical quantity. How much a system gives, compared to how much it takes in

Surely you've heard of the phrase "a machine can't give you more than you give it". But why is that? Well, because some of the energy given itself is used up for the machine's function. In this case, our system, made up of one or more machines, converts energy from one form to another through a series of processes. Processes which in the real world, are not totally reversible. Suffice to say, losses always exist.

But how do we count those? That's where the second law of thermodynamics comes into play. Efficiency as per the second law is a system's work output compared to the maximum possible work output it would have, were things optimal (again, very roughly). It describes how close to optimal function we have, in a thermodynamic process (or more than one processes)

ηΙΙ = work output/maximum possible work output.

And here's where the philosophical aspect begins. In our daily lives, every person is faced with a series of tasks, challenging or otherwise. Some rise to the challenge, some perform adequately, some others do not. We could draw a metaphorical parallel between the two laws of thermodynamics and people.
Where efficiency according to the first law would be

η = output/resources.

Depending on the concept we can substitute the resources with many different things, or even all of them if the output is broad enough. Notable examples of "resources" include time, education, financial resources, etc. We could in a sense measure what people accomplish in life based on their output/resources at their disposal ratio. The various potential "outputs" (or even all of them if we were bold enough to generalize the ratio enough for the entirety of the life or life period of an individual or group), make this quantity very hard to compare to another individual's, or group's efficiency

And this is the difference with the second law. Using the same logic, I would argue that efficiency as per the second law would be

ηΙΙ = Output/ maximum possible output

Now we are getting somewhere. The first law is all about how much an individual or group of people produces compared to what that individual or group "absorbs" (in the form of resources). The second law is all about how optimally said individual or group's production or output would be, under the same circumstances. Which means that the second law measures how closely one approaches the limits of their possibilities.

This leads to certain interesting discoveries. More importantly, what is more important?


On a first glance the first law seems to be more important. If you are accomplishing more, in a shorter timeframe, surely you are more capable. Professionally speaking you have a much higher chance of success, but the same conclusion can be extrapolated for various other aspects of life as well.

However the second law, measures not how much you accomplish, but how close to your maximum possible accomplishments your output is. In a sense, it could represent all the opportunities you have seized, the chances you've had in life, out of all the opportunities you could have taken.

It seems that the second law is definitely very important as well. People with disabilities have to strive to meet marks that other people can meet without any sort of effort. Yet the first group finds acceptance, cheers and encouragement as they reach those milestones. That is because they approach their own limits, very very closely. The reach of what they could possibly do.
Stephen Hawking. Notable scientist who achieved a lot in the field of theoretical physics, even despite his ALS

But of course, very often, in life, it is the actual output that matters. Even if someone is very efficient according to the second law, if the limits of their potential are too low, then the work they produce, or output, is also low. An example of such a mechanism is the common bicycle, which is one of the simplest energy converting devices in existence. Through the use of a single chain and one gear, it converts your potential energy into kinetic energy, or movement. Its simplicity also means it suffers very few losses of energy, through negligible amounts of friction between the bike's chain and the gear along with the rest of the environment of course. But a bike is no plane, or train, or car All of which are a lot more complex, and achieve the energy conversion a lot less efficiently, but with greater results still.

If you made it this far, what is your take on this? What do you think is more important and in which aspect of our lives?

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