What is random?

[Angry Floof]

I know what the word means, but is there truly such a thing as randomness? Or is there a level of complexity of pattern that our perceptions and technology simply can't see?

It's not that I'm attached to any ideas of a grand pattern to explain everything. I for one am quite happy with unpredictability and uncertainty, but I do wonder how much of what we don't or can't predict do we chalk up to random? Can we even know for sure if randomness really reflects anything of reality?

 

[steve_bnk]

Random means uncorrelated, or nopattern.


Put 900 red balls and 100 black ballsin a large bowl.


Shake and mix as thoroughly as you can.


Pick a ball, record its color, put itback in the bowl, and reshuffle.


As you repeat the process on any givenselection or sample there is no pattern of colors that will allow youto predict what the next color picked will be.


Flip a coin 100 times. For a decentlyrandomized toss the average of heads and tails will be close to50/50. But on any toss the fact that the prievious toss was a heador tail has no effect on the next result, uncorrelated events.


Some gamblers at the craps tables thinkthey see patterns and bet accordingly.


Generating random numbers andsequences are important in many applications.


Random number generators done insoftware are pseudo random, the sequences will always repeateventually and have some pattern. Critical for encryption.


Hardware generators have used cosmicnoise and electronics noise.


The old 'numbers game' in which peoplebet numbers in some cases used the daily ending numbers of the stockmarket.


Whether or not processes that appearrandom to us are just the inability of us to measure is an openquestion.


What is random is actually an importantquestion. In his chapter on random number algorithms Knuth simplysays random is what fits your definition of random. One way to lookat it.

http://quanterion.com/FAQ/Bathtub_Curve.htm


In the 'bathtub curve' applied to humanmortality phase 1 is called infant mortality. A period of highmortality due to things like birth defects. Phase 2 is the 'usefullife' adult period in which you are more likely to die from chanceevents. Hit by lightning, hit bay car, catching a disease.Unpredictable random events.

 

[fromderinside]

OK.

 Randomness This gets at what is meant by random

 [B]Pink noise[/B] is the noise form I used to study minimum audible movement angles because it best matches the form of our sound sensitivity function.

 [B]Shot noise[/B] .... ff the laser brightness is reduced until only a handful of photons hit the wall every second, the relative fluctuations in number of photons, i.e., brightness, will be significant, just as when tossing a coin a few times. These fluctuations are shot noise.

 Johnson-Nyquist noise a wide spectrum of electromagnetic noise appearing in electronic circuits and devices as a result of the temperature dependent random motions of electrons and other charge carriers.

and

 Noise (electronics) In electronics, noise is a random fluctuation in an electrical signal, a characteristic of all electronic circuits. Here is where random is broken down in relation to physical process.

Don't blow a fuse.

 

[Atheos]

I'd say nearly everything we consider to be random is actually explainable in terms of pure mathematics provided one can account for all the criteria. The nature of time contributes to the illusion of randomness when (for example) a pair of dice are rolled. If one were to be able to know the precise starting positions and orientations of the dice, all the factors of vector, duration and encapsulation shape of the palm in which the dice were shaken, the angle and velocity at which the dice were tossed, the precise measurements, bumps and surface qualities of the table on which the dice landed, etc., one could predict with accuracy the result of the roll.

The fact that it is currently impossible to know all of these things before the roll is started makes the outcome impossible to determine. This is the illusion of randomness and it is completely compelling for all intents and purposes.

 

[NobleSavage]

https://www.random.org/

Perhaps you have wondered how predictable machines like computers can generate randomness. In reality, most random numbers used in computer programs are pseudo-random, which means they are generated in a predictable fashion using a mathematical formula. This is fine for many purposes, but it may not be random in the way you expect if you're used to dice rolls and lottery drawings.

RANDOM.ORG offers true random numbers to anyone on the Internet. The randomness comes from atmospheric noise, which for many purposes is better than the pseudo-random number algorithms typically used in computer programs. People use RANDOM.ORG for holding drawings, lotteries and sweepstakes, to drive games and gambling sites, for scientific applications and for art and music. The service has existed since 1998 and was built by Dr Mads Haahr of the School of Computer Science and Statistics at Trinity College, Dublin in Ireland. Today, RANDOM.ORG is operated by Randomness and Integrity Services Ltd.

 

[fromderinside]

Even if it were possible for one to know all things before the dice began to roll one cannot know what is going to happen as the dice are rolling since everything interesting is in flux all the time. Sure one could develop predictions, but, computers often produce 0's when 1's are programmed. Never know when that cute little particle down the street is coming from somewhere else to much things up.

 

[Atheos]

Yeah, but can it not be argued that these things that are in flux are little else besides things we don't yet fully understand? What if we at some point in the future learned the mechanics behind those cute little particles living down the street? My theory that it would be possible to predict accurately the result of the dice roll is based on knowing all the criteria, not just the ones we can know now.

 

[fromderinside]

Isn't enough to understand things are determined? If we were beings aware of all thing in all time, which we demonstrably are not, we might ultimately know. Since we aren't we shall be always have uncertainty about time, space, place. So, for us such is not 'knowable'.

 

[ryan]

I think that the OP meant randomness in general, not relative to a human. In that case, the only randomness there is might quantum mechanics.

 

[rousseau]

Either everything or nothing, depending on how you look at it.

 

[doubtingt]

Randomness does not imply uncaused or necessarily without a pattern.

The vast majority of the time the term "random" does not refer to a single variable but to the relationship among variables. Each single variable can have a pattern to its variance, such as a bell-curve, yet if their is no systematic relation between the variables than one is "random" with respect to the other. As is the case with language, we often leave much of this explicit such that it can superficially seem like we are referring to a single variable as random, when really the other variable is just implied. Random genetic variation is a good example. The variations are very much caused in systematic ways by factors and the distributions might be highly explicable in mathematical terms, such as variations in the genes (and their phenotypic effects) that impact height, with there being reliably more variations that deviate only slightly from the mean height than variations that deviate highly, resulting in a bell curve distribution. The "random" merely refers to the fact that their is no reliable relationship between which variations will appear for the first time and the properties of the environment that relate to which variations would be adaptive.

Likewise, a random lottery merely means that there is no reliable relationship between which numbers are drawn and which numbers people have picked (whether an individual person or collectively what the most picked numbers were). In sum, random usually just means the same as the lack of a systematic correlation or - with something else.

 

[Malintent]

There is no such thing as "random"... only really really really really complicated.

The flip of a coin is not "random", it is determinant on the forces applied to the coin, aerodynamic forces applied to the coin as it flies through the air, gravity, and the angle and hardness of the surface(s) struck as it lands.

Or, does someone want to argue there is an indeterminable (not just indeterminant) force "out there" that "mixes it up" a bit.

 

[ryan]

There is no such thing as "random"... only really really really really complicated.

The flip of a coin is not "random", it is determinant on the forces applied to the coin, aerodynamic forces applied to the coin as it flies through the air, gravity, and the angle and hardness of the surface(s) struck as it lands.

Or, does someone want to argue there is an indeterminable (not just indeterminant) force "out there" that "mixes it up" a bit.

What about two different positions where an electron has an equal probability of being in? For the electron to be in one position rather than the other may be truly random.

 

[steve_bnk]

There are ideal models and real world approximations.

The level of approximation depends on the need.

In Scilab I have used the internal random number generator to do Monte Carlo simulations. The generator would be totally inadequate for a lottery.

In an experiment to me random means there is no correlation between variables.

Flip a coin 20 times, the probability of the 21st flip remains 50/50.

 

[fromderinside]

NSRR

 

[Malintent]

There is no such thing as "random"... only really really really really complicated.

The flip of a coin is not "random", it is determinant on the forces applied to the coin, aerodynamic forces applied to the coin as it flies through the air, gravity, and the angle and hardness of the surface(s) struck as it lands.

Or, does someone want to argue there is an indeterminable (not just indeterminant) force "out there" that "mixes it up" a bit.

What about two different positions where an electron has an equal probability of being in? For the electron to be in one position rather than the other may be truly random.

Maybe.. but given the track history of Science, we most likely just don't understand all the forces at play.