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For videos explaining Universe and evolution we will need to understand what the term force exactly means in physics. It is because Universe is of physical nature and it is physics that describes Universe and since the beginning of science physics has been dealing with forces.
So what is a force? First let’s have a look on definitions that are already available.
A force is an influence that can change the motion of an object says wikipedia.
A force is an interaction between the objects because of which they make changes in their motion says one learning internet site.
A force is an interaction between two or more physical objects that causes a push or a pull between them says another site.
A force is a push or pull upon an object resulting from the object’s interaction with another object says yet another site that concentrates on teaching physics.
I agree with all those definitions. As you see physics has no problem defining force which is no wonder because physics is dealing with forces for centuries.
Definitions of force always say that it is an interaction of two or more objects that is causing something which usually is a movement.
Now let’s have a look on my definition of force that is useful for our future videos.
Force is always a manifestation of interacting material objects. It is the actual presentation (perception) of interaction of matter.
What I mean with manifestation of interaction is that the force actually is of non material nature that means that force does not exist as such and it is always the material objects interacting with each other what we perceive as a force. So force is only a perception of interacting matter by another material system such as our human brain.
What an interaction exactly is please have a look on my video about system theory and its author Ludwig von Bertalanffy that I have published here on this channel earlier. This video also explains that Universe is strictly of a hierarchical nature.
Now let’s have an example of a force and its explanation. Let’s have a look on suction force of a vacuum cleaner. Every child knows that this device is producing suction force that is capable of sucking small objects into the vacuum cleaner. How such force originates is easily explainable.
On this second image you see how the vacuum cleaner looks from inside. As many of you know there is an electric motor with blades. And it is the rotating blades that are producing sucking force. As the blades interact with air molecules, they move the molecules inside vacuum cleaner and as a consequence small objects are moved inside as well. This is called sucking force.
When the interacting material objects are easily visible or detectable we have no problem to say that the action is being caused by the objects themselves. But what if the objects that we perceive as a force are on another hierarchical level and we are unable to see them or even detect them with our available devices?
For example what if the material objects causing an interaction are so small that we have no clue about their existence?
In this case physicists and humans in general tend to use the term force instead of talking about interaction. That is logical because physicists have no idea what objects are interacting here because the objects are non detectable.
But that does not mean that the objects are not there and that they are not causing interaction. They are!
The force as we perceive it is always a perception of interacting matter. This must be and is an universal principle because there is no information available that something would disturb this principle and secondly if you are building a system of scientific knowledge such as physics you must always keep on having a system where everything is based on same principles and where everything fits together.
Here I want to mention Albert Einstein and his wrong views on origin of gravitational force. Einstein was certainly wrong when he postulated that gravity is not a force. It is and the reason why we cannot find material systems causing this interaction is that they are probably so small that even today’s particle physicists have no clue where to look for them.
When we have explained what a force is and that behind every force there are always interacting material objects and nothing else we are ready to learn net videos explaining the nature and functionality of Universe.