In this article, we talked about quantum entanglement. While doing so we touched on “action at a distance”. In this article we are going to use it as an introduction to the Principle of Physical Interactivity.
Let us summarize action at a distance with a quote from the article:
Suppose you have two particles, particle A and particle B. Suppose these two particles can interact in some way such that if particle A does something, it will cause particle B to change state. Perhaps if particle A emits a smaller particle that strikes B, particle B will spin in a different direction. We will call that change in direction “event C”.
If particle A and particle B are to interact to cause event C, then some kind of physical action must occur. The particles must act upon each in some way which then causes event C.
Particle A will have to emit some particle, vibrate some physical connection between particle A and particle B. Or somehow affect some kind of physical interaction. An interaction being some kind of action taken by A which effects B.
Otherwise, how else could particle A cause particle B to change the direction of its spin? By non-physical means? Using an abstraction? I think not…
Let us try to put this more simply. Let us say that we have a computer and a wireless keyboard connected to the computer. It is connected by a wireless connection.
We will use these two macroscopic objects as our example. However, it is trivial to extend these examples to subatomic particles and apply some simple logic to them.
Even though modern physics insists the subatomic world is not rational. Or that it is not subject to the laws of logic.
Now, suppose we press the button “A” on the keyboard. As a result, the letter “A” now appears on the screen. In other words, our keyboard has interacted with the computer.
Now, what has happened here? Is this witchcraft? Should we expect the Spanish Inquisition?
I am going to explain this by laying down a simple principle, which I am going to call the Principle of Physical Interactivity.
The Principle of Physical Interactivity says that in physics, all objects that interact with one another do so by physically interacting with one another. All interactions in physics are the interactions of physical objects with each other.
What does this mean? What do I mean by physical? I mean that which has shape or “physical extension”. It is not an abstraction, not an attribute, not a relationship, not an action. It is a non-abstract entity.
So, when I say that all objects interact via physical means, I mean that this interaction takes place when two physical objects act upon one another. The interaction is not by means of abstractions. It is via the actions of physical entities.
Take the computer and the keyboard. Are they physically interacting? Yes. There are physical objects of some kind traveling from the keyboard to the computer. Or some other kind of physical activity in the keyboard which causes another physical action to take place in the computer.
That interaction might be described by saying that there are waves traveling from the keyboard to the computer. The waves are abstract descriptions of some kind of motion/relationship.
In that case, the keyboard interacts with the computer by some physical process involving the keyboard interacting with some kind of physical medium.
The point of the Principle of Physical Interactivity is that some kind of physical interaction is required.
Must Objects Touch?
What does it mean for objects to touch? I take it that they must have direct physical contact. Is this necessary?
No. The Principle of Physical Interactivity merely says that there must be physical interaction. It does not require that two objects are in direct physical contact.
Let us return to the example of our computer and wireless keyboard. For the wireless keyboard to send a signal to the computer, must the keyboard and the computer be touching? Must they be in direct contact via some part of each other?
The Principle of Physical Interactivity does not require this. It merely requires some kind of physical interaction. It does not require that the computer and the keyboard directly touch one another.
Other Forms of Contact?
Must there be some kind of invisible thread directly connecting the keyboard and the computer? The Principle of Physical Interactivity does not require this either. Physical interaction need not take place via objects such as a thread that directly connects the two objects.
How then can they interact? Well, the keyboard might send waves through a medium such as air, which the computer picks up.
Hold on now, I thought waves were abstractions? Additionally, I thought you said that the computer and the keyboard must interact by physical means?
The wave is an abstract description of objects taking some kind of action, of causing something to move through the air in a wave pattern and to hit the computer. Therefore, the keyboard and the computer do interact by physical means.
(Note that here on this site, we define waves as a kind of abstraction that describes motion or some other kind of relationship. Thus when we say “there is a water wave”, what we are talking about is an abstract description of a bunch of water molecules arranged in that shape.
The referents of the concept of wave is the water molecules, the concept of “wave” describes the fact that they related in that pattern).
This is still a kind of physical interaction between the computer and the keyboard that causes the letter “A” to appear on the screen.
To sum up, this physical interaction does require some form of physical interaction via touch or some other form of medium.