The Laws of Thermodynamics
Physics is a wonderful thing. It can tell us how the universe works, and gives us the ability to manipulate our surroundings to impressive ends. Luckily for us, it also gives us rather unbendable laws which, no matter how much we may wish it, cannot be violated. One of these is "conservation of energy". This is one of the things that Over Unity would violate.
The First Law of Thermodynamics
I'm going to violate a Human law of Physics now, that is, to reference Wikipedia...
Energy can be transformed (changed from one form to another), but it can neither be created nor destroyed.
When you burn gas, you are converting energy contained within the molecule into thermal energy. Energy was used when the carbon-hydrogen bonds in the methane (natural gas) molecule were created, and when you break them by burning the gas, energy is released. By burning the gas, you are not creating energy, but transferring it from one form to another. This is true of all "sources" of energy, without exception.
For those of you of a mathematical persuasion...
dU = dQ + dW
where dU is the total energy contained within a system, dQ is the total energy flow into or out of the system and dW is the total amount of work done on or by the system.
The Second Law of Thermodynamics
The First Law of Thermodynamics says that energy cannot be created or destroyed. The Second Law of Thermodynamics goes further and puts constraints on systems where there is a transfer of energy. The Second Law essentially says that there is no such thing as a perfectly efficient system, i.e. you will never be able to get 100% of the energy out of a system that you put into it due to losses by heat.
Let me explain that a little better...
The Second Law and Heat Engines
Let's take the simplest example of energy transfer, that of one hot body and another cooler one. If you put these in contact with each other, you would expect the hot body to cool and the cold body to warm until they are both at the same temperature.
Now, how would you derive usable energy from this situation? You'd put some kind of heat engine in between them, that takes the flow of energy and redirects it to a useful end. In the real world, say, we take fire, use it to heat water which drives a turbine.
The problem is that energy will always flow from the hot body to the cold one. If there were no colder body, there would be no net flow of energy at all. So, while some energy will be redirected to power our turbine, some will still end up in the cold body. This simple concept can be extended to all systems where there is a flow of energy.
To sum up: energy can be neither created nor destroyed. No energy generation system is 100% efficient, as there are always losses to the environment. This is exactly what Over Unity claims to violate.
Here's a video from YouTube of a song by Flanders and Swann, entitled "First and Second Law". I don't know why the video is all about Star Wars, but this is the only video I can find! Enjoy!
Claims of Over Unity
Search on YouTube for Over Unity and you will find a plethora of people claiming to have invented some sort of free energy device, mostly in the form of a motor, which apparently generates more power than is used to drive it. Others claim to have invented some arrangement of permanent magnets whereby a flywheel will, by the arrangement of these magnets, move on their own for ever.
Anybody claiming to have invented a machine which creates energy, I'm afraid to say, is either trying to con you, or is deluded or confused. It is fair enough to have an open mind when it comes to the possibility of new Physics, but this is not new Physics. This is quite old Physics. Frankly, if they were to violate the laws of thermodynamics, then all of modern technology would be based on the wrong foundations. Since everything is still running smoothly, based on these laws, we can assume that these garage inventions are not what they seem.
Not only that, but why would they have created these machines in their garages, promoting it on YouTube? They would have papers in peer reviewed journals, and if their discoveries were true, there would be no shortage of Nobel Prizes. Please do not be drawn in by these claims, which seem to be growing in popularity.
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