Help me understand this. If entropy is about signal transmission, and is measured by “how much information is missing,” it implies a transmitter and receiver – in other words, a relationship. Entropy is an appealing notion because at first glance the receiver of the information cannot suddenly know more than what is transmitted. But the amount of information the receiver can receive seems to be highly relative and transformable.This is if I understand correctly that entropy is not a measurement of a system’s physical properties, but of how much information is missing when that system is observed. For sure, a system will emit is information, and there will be a less than 100% reception of that signal for any system observing it. That number cannot be 101%…. But there are two sides to a relationship, and a system’s entropy is not related to some total “information” it “contains”… So there are simple workarounds to that 100% threshold.
For example, if I look at a blade of grass that I hold in my hand, I can only receive so much information about it, and I cannot get more information than what it is transmitting to me… Unless I then look at it under a microscope and now the information loss (entropy) has decreased. If entropy were a law of the universe, my act of changing my receptor would be “impossible.”
It seems to me that labeling entropy as an unbreakable law is a naive notion, and instead I see it as a useful property of observation. Does entropy deserve the status of “law of the universe”?
The subject of entropy is, appropriately highly entropic. There are a lot of different ways that the word is used, some more figuratively than others. Thermodynamic entropy is not the same as information entropy, in the sense that if we make an MPEG compressed video of a glass of ice melting into room temperature water, the first half of the movie would take more resources to compress than the last half, given that the last half would feature only a glass of still water. As the thermodynamic entropy of the actual ice increases, the information entropy of the content of the video decreases. The sensitivity of the video camera is limited, so it can’t detect the microstates of the water molecules.
I think this speaks to the question of perception, and how our designation of what constitutes a ‘system’ is more arbitrary than it may seem. All of our instruments and all of our sensing and sense-making capabilities are potentially as limited as the video camera. Our attention is squeezed into an anthropocentric range, so that our window on ourselves and the universe does not allow us to discern ultimately what is ‘a law of the universe, or simply an assumption based on our perceptions’. Everything that we can understand about the universe is furnished to us only by our perceptions, intuitions, and understanding.
Our perception leads us to expect a universe of laws and realities beyond itself, but these too are either ultimately subjective conditions, or else subjectivity itself must include the possibility of transcending itself. The difference between what we presume to be our private perceptions and what we presume to be something more is…. entropy. There is no way to obtain 100% of the information about anything. Even given omniscient access to the entire history of the universe, the nature of the universe may be intrinsically open ended within any given inertial frame.
What I am suggesting is that just as entropy is the gap between what we experience and what we think could be experienced (‘objectively’), what we consider information may only appear to be finite because of the gap between our native perceptual frame of reference and the target frame of reference. Rather than being a true description of what a phenomenon is, ‘information’ may be as fictional in its amputation of subjective qualities as perception is in its failure to pick up on physical properties. The definition of entropy itself can be thought of as gradually reversing or flipping in proportion to the distance (literal and figurative) between two perceptual frames. Take these words for example. If you read English, then your absorption of their meaning is rather loose and general. You get the idea of what I am saying, and even sort of ‘hear’ an inner narrator voice that stands in for me. It’s all rather fuzzy, but it works really well. Entropy is actually what allows you to get the gist of what I am saying or even what I am not saying (reading between the lines).
By comparison, someone who cannot read English at all may have a much clearer view of what these characters ‘actually’ look like (without as much fuzzy interpretive conditioning). In the same way, some people find it easier to draw realistically if they are copying an image upside down. Entropy and significance, subjectivity and objectivity are not functional properties, they are aesthetic ranges. The universe as a whole can, in the same way, be considered primarily an aesthetic phenomenon as a whole, in which any part can reduce another to a functional stereotype using variations on the theme of distance or insensitivity.