Is Anything in the Universe Truly Random?

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The discussion revolves around the nature of randomness and determinism in the universe, questioning whether true randomness exists or if everything is ultimately deterministic. Participants explore concepts from quantum physics, chaos theory, and probability, noting that while quantum mechanics introduces elements of unpredictability, classical systems often appear random due to complex interactions and incomplete knowledge of initial conditions. The conversation highlights that randomness can be defined in various ways, including uniform distribution and the inability to predict specific outcomes. The role of human perception in interpreting randomness is also considered, with examples like coin tosses and the behavior of particles illustrating the complexities involved. Ultimately, the dialogue suggests that while many phenomena may seem random, they are often rooted in underlying deterministic processes, raising further questions about the definitions and implications of randomness in both scientific and philosophical contexts.
  • #31
marty1 said:
An unsolved differential equation.

An unsolved whatever. The idea that nature must obey the preconceptions of scientists is so old and has been disproved so many times you'd think academia would insist by now on everyone receiving a doctorate getting a tattoo that says it just ain't so. A new law of nature, science is invariably proven wrong.
 
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  • #32
Pythagorean said:
Well, first it depends on your definition of "True" randomness (I agree that Wolfram's definition is not sufficient, though I think part of it is necessary).

But, more importantly, I'm pretty sure quantum chaos is still a very open subject. We have very little knowledge about open quantum systems our large-scale coherence. Deterministic chaos and quantum probability must be reconciled somehow (some might point to the deficiency in the definitions of space and time, as they manifest at the Planck scale, but others point out the significance of so-called "subplanck" structures at these scales:

http://www.ncbi.nlm.nih.gov/pubmed/11507634

You seem to imply that:

quantum probability --> deterministic chaos

But I don't think there's any evidence for that at all. Of course, I could be completely wrong, but I'd be interested to see the evidence.

In my view, these are two huge, complex concepts based off a myriad of human assumptions and in different aspects, both:

quantum probability --> deterministic chaos
deterministic chaos --> quantum probability

are true (or our understanding and language for cause and effect is currently inept)

Maybe I'll try to simplify my platform, maybe not...

A mechanism that randomly causes events can at times produce order (by chance). Some of this order may result in other mechanisms that can themselves cause events but the important ones are those that have lasting consequences that reinforce their own persistence. My position is that those larger mechanisms have an abillity to produce random results that diminishes with scope.
 
  • #33
Pythagorean said:
But, more importantly, I'm pretty sure quantum chaos is still a very open subject. We have very little knowledge about open quantum systems our large-scale coherence. Deterministic chaos and quantum probability must be reconciled somehow (some might point to the deficiency in the definitions of space and time, as they manifest at the Planck scale, but others point out the significance of so-called "subplanck" structures at these scales:

http://www.ncbi.nlm.nih.gov/pubmed/11507634

I suppose I can agree. The fact that a quark, for example, seems to be a persistent fixure in our universe would imply to me that there is at least some structure smaller than it keeping it here although we might not be able to ever measure it because its reach ends there (the machinery inside does not cause events independently "outside" the quark).
 
  • #34
Mathematically, a purely random process is one that has maximum entropy. You can use this definition to really study random-ness in a well defined mathematical context.

As has been pointed out, one thing relates to whether you have all the information in order to describe an assess the process and one thing to be aware of is that most things that are analyzed in a systematic way are inductive and extrapolatory.

By inductive and extrapolatory I mean that we start off with a very narrow spectrum of observations and then try and explain the entirety of the system given this information.

This is the opposite to inductive where you start off with a complete description of something and then use this to get attributes for some particular subset of the system.

The inductive approach is what scientists do and the deductive approach is what mathematicians do and somewhere in between is what happens when you look at everything being put together.

Now in statistics (which is what science is using as its language ever more slowly), we can make inferential statements about things but we do it with a machinery of mathematics behind it (which is bound by its own assumptions).

But statistics and its use is based on having incomplete information (a sample, is usually always considered to be a narrow subset of the entire population) and the best we can do is make an inference under relative uncertainty and this is what statisticians and people that use statistics actually do.

One final thing about randomness is so far, we can't really describe or easily deal with models with severe complexity both in an algebraic and also in a geometric form. Most people can't deal with more than 5-10 variables and beyond that it becomes too complex.

This relates to randomness in a way that a lot of things are called "random" if we can't see an immediate pattern even though the pattern may exist and may not really be hard to describe algebraically or geometrically even though its hard for "us" to do so.
 
  • #35
You could say the opposite for "ordered" and claim mathematically it has minimum entropy and we have incomplete information on whether anything is "truly" ordered. Furthermore, we can't fully model orderly systems and even the 3 body problem continues to frustrate.
 
  • #36
An ordered system in the context of a particular language may have minimum entropy and in that case, the system under that description is fully deterministic within that descriptive capacity.

Just because you can't get something in the descriptive capacity you want doesn't mean that it doesn't have minimum entropy under another descriptive capacity that is purely deterministic.

If you can't get things in terms of exponents and elementary functions, then this does not imply that you can't get a minimum entropy description under some other descriptive capacity, and unfortunately that is what a lot of people do.

What you are saying is ridiculous.
 
  • #37
Then you are merely splitting semantic hairs insisting anything can be defined as "deterministic" which is absurd.
 
  • #38
It seems to be better to separate process from state when talking about ordered vs random. A random process can result in an ordered state. This is not a deterministic process, however, there could be certain states that are stable enough to survive long enough to have consequences. Combinations of state that can have consequences (cause events?) are themselves processes.

Contrary to popular believe there are many identical snowflakes. The process creating them is not deterministic, but is limited in its degrees of freedom enough that the path of crystal formation can be followed more than once by chance alone. Each establishment of an ordered state at each "tick" of the clock limits future possibilities as the current state is used as "input" to the process generating the subsequent "output" state.
 
  • #40
The definition of "random" should include some measure of the influence that the pre-existing state has on any subsequent change in state. A choice made under no influence is indeterministic at one end of the scale. The degree of influence is measured in both space and time. Maximimum influence, maximum determinism, is the light cone into the past.
 
  • #41
marty1 said:
It seems to be better to separate process from state when talking about ordered vs random.

Which violates quantum Indeterminacy and would make all of quantum mechanics utterly useless. A recent experiment involving weak measurements that compensate for the observer effect without collapsing the wavefunction has confirmed the Ozawa formulation of the HUP. If confirmed by other experiments it would elevate Indeterminacy to the status of a physical law (if that isn't a contradiction!) Similarly, there is an effort underway to see if it is possible to prove whether Indeterminacy applies to causality itself.
 

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