Randomness

[xodkrm]

My current question at hand: what exactly is random?

A good example would be flipping a coin.
You flick it up with your thumb, catch it, and the side that faces towards you is the result.

We call this "random", but actually, if you were to exactly calculate the strength/speed in which the thumb manipulates the coin, we can find out the result, using some basic physics.

So Action ---> Result.
If we can figure out the action, we can understand the result.

Vice versa, if we know the result, we can know the action?

If we were to apply this logic to more bigger questions at hand, such as the randomness of eg life, it's weird. For me, I kinda start doubting random, does it exist?

Discuss.

[migidu]

Random is associated to things in which we cannot actually what the result will be given so many factors. like in your coin, there are only two given possibilities, either heads or tails. but if we have a fixed output given many factors and conditions, we do not call this random. since we can predict it.

Random can be perceived differently fom different observers. As humans, we have the instinct to observe the phenomenas around us. When we have a set of data, then we make an experiment. Not being able to get a logical pattern we say its random.

In Life, things may seem to happen in random, but i believe there is a pattern we follow since everything happens for a reason, but not always we find the reason. It may only be an illusion that there is such thing as random, but actually not. I think it is only our inability to understand the pattern of such things, that why did this thing happen instead of that, that we say things are random.

here's wikipedia link to random : http://en.wikipedia.org/wiki/Random

So my conclusion, randomness is more like a label to such phenomena observed. A popular randomness would be here at the forums. People start discussing about random, then one person suddenly posts "hey chocolate icecream, cookies n cream tastes good". Under that situation, we say "that was a random posting". :) There are a plenty of random posts out there . . . :)

[Oblongato]

If I am reading you right, what you are talking about is causality. And if you believe that the universe consists only of matter and energy, and that causality applies all the way down to the basic building blocks of the universe (whatever they may be), then randomness does not exist. And if randomness does not exist, the universe must be deterministic.

If you believe the universe is not deterministic, they please show me where causality breaks down. ;)

[Nostradamus]

If you believe the universe is not deterministic, they please show me where causality breaks down. ;)

http://en.wikipedia.org/wiki/Radioactive_decay

It would appear that the only thing that is not random is radioactive decay. As for causality it makes perfect sense to me. Every cause must have an effect. Every effect must have an effect of it's own, a chain reaction spreading back to the big bang.

However, how do you feel knowing that according to causality there is no such thing as free will? I for one do not mind so long as I can understand the reason for this chain of events.

Also, can causality be used to prove The Butterfly Effect? Again, this makes sense to me although I don't think it could be as catastrophic as a buttefly causing a hurricane.

Finally, there may be no such thing as randomness due to the multiverse theory. If one were to flip a coin then it would seem that the result will either be heads or tails. But in theoretical physics, it may be a possiblity that both results occur and a paralell universe is created for each. (This issue has been discussed in a few other threads such as my Predestination and Schrodinger's Cat threads)

[Oblongato]

I am still unconvinced that radioactive decay and other subatomic phenomena are truly random. I find it more likely that the causal factors at work are invisible to us. It would be too coincidental if the point at which everything becomes random just happened to be the point at which our powers of observation have reached their limit.

Another idea I've been thinking about is what the consequences would be of true randomness anywhere in the system. How can anything appear coherent if the level just below it is random? Would it even be possible to have a system built on random behavior of matter and energy?

My thinking thus far is that randomness anywhere in the system, but especially at the basic level, would preclude order at any level in the system. As a model, we could look at the behavior of matter and energy at a higher level where our predictions of their behavior are relatively good. Let's take the behavior of gravity. If we were unable to predict whether an object when released was drawn toward the massive object (Earth) or was repelled by it, what other aspects of the behavior of matter and energy would be affected? If this one aspect, gravity, were random, I would argue that all order in the universe would fail. Would not the consequences be the same at the subatomic level?

How can order even exist when it must interact with randomness? I suggest that if any of the building blocks are random, there can be no system because causality is the prerequisite for a system.

[Modred]

If everything is purely deterministic, what caused the first effect?

Now, to leave the metaphysical realm of debate, let's look at another coin-flipping example. Hold a fair coin vertically within a vacuum at a given distance above a surface. Release the coin and record which side faces upward when it settles. Can anyone deterministically predict which side will show?

The coin should hit on the edge with velocity perpendicular toward the surface. We have no torque, no air resistance, no human interaction to game the system. This scenario is incredibly more simple than a coin toss, but I propose that you cannot tell me which side will face upward in any particular instance.

I think it's fairly obvious that the coin will not stay on its edge, so which way does it fall? In a purely deterministic scenario, we could count on the coin always falling to the same side, regardless of how many times we repeat the experiment. However, I guarantee with almost 100% certainty that this coin will not always settle to the same face. In fact, it should land on either face approximately the same number of times.

What do we call it when we have a set number of possibilities, each with the same probability of occurrence? That, my friends, is a random event.

[Oblongato]

There is no evidence that there was a "first effect." If such evidence is found, perhaps it will suggest a first cause, perhaps not.

Whether the universe is deterministic, however, (universal causation) does not depend only on our own ability to predict the outcome of an event. The fact is, true randomness (as opposed to the use of the word random to refer to behavior we cannot predict because we cannot keep track of the variables) is possible only if causation breaks down, i.e. if physical laws break down. This semantic distinction between the two definitions of the word "random" is an essential aspect of the discussion of determinism.

Your statement that you "think it's fairly obvious that the coin will not stay on its edge" is based on ... what?

In this example we would be talking about measuring variables of the equation with incredibly minute tolerances; we would even have to be aware of events on the quantum level, probably. Our current state of technology does not offer us this opportunity, effectively hindering us, therefore, from predicting such outcomes.

Holding the coin "vertically within a vacuum at a given distance above a surface," for example, would have to be done with a precision that we are not capable of if we are to predict the outcome. Further, the atoms themselves will not make actual contact - rather, it will be the forces in the sub-atomic particles (which are in motion) that will determine the outcome. We are not capable of observing these these particles in action, rendering us effectively unable to predict in such cases. The problem with your example is precisely that it is not simple; rather, it is astonishingly complex. In the end, it is the complexity which prevents us from making an accurate prediction. There is nothing about the example, however, that suggest that physical laws break down. And if physical laws do not break down, anywhere, universal causation (determinism) applies.

[Modred]

The fact is, true randomness is possible only if causation breaks down, i.e. if physical laws break down.

Unlike my coin example, we cannot verify this through experimentation. Might I ask how you know this, or if it's simply conjecture? On another note, has anyone ever proven that by tracking every subatomic particle, one could predict exactly what will occur for some given instant of time? Your entire argument rests on this assumption.

[Oblongato]

As I've mentioned in other threads, since we are part of the system we are looking at, there is no way we can prove conclusively whether it is deterministic or not. To be quite frank, we can never know know this because we cannot look at the system from the outside.

However, since we are speculating, it is possible to argue that one theory is more logical than the other.

This is the basis of my argument:

It is physical laws that have allowed us to predict the behavior of matter and energy at many levels. Every successful prediction of the behavior of matter and energy is evidence for the existence of causation; indeed, I don't assume that you would deny causation exists.

On the other hand, We have encountered no instances of complete non-predictability of matter and energy except at the quantum level, which, it just so happens, is at the very limits of our ability to observe. What takes place beyond our ability to observe? We have no way of knowing, obviously. Should we therefore assume that the behavior that we are unable to predict at the subatomic level, except as a probability, is truly random, that physical laws break down at that point? Or would it be more logical to assume, since at least the probability of the position of an electron can be predicted, that there are physical laws there, too, which we simply have no means of detecting?

Since true randomness would be unprecedented, I consider the latter assumption significantly more logical.

A further point is the question of whether it is even possible to build a system on a basis where causality does not apply (i.e. the subatomic level), where matter and energy may behave randomly. I suggest that if this were the case, a system would not be possible, that order itself depends on a basis of universal causation.

[Battlecruiser]

The coin should hit on the edge with velocity perpendicular toward the surface. We have no torque, no air resistance, no human interaction to game the system. This scenario is incredibly more simple than a coin toss, but I propose that you cannot tell me which side will face upward in any particular instance.

I think it's fairly obvious that the coin will not stay on its edge, so which way does it fall? In a purely deterministic scenario, we could count on the coin always falling to the same side, regardless of how many times we repeat the experiment. However, I guarantee with almost 100% certainty that this coin will not always settle to the same face. In fact, it should land on either face approximately the same number of times.

What makes you so sure it wouldn't stay on it's edge? If it is perfectly thrown vertically up, I would think it would bounce when it lands on it's edge but still stay on it's edge. At least that's how I imagine it. There is no unbalanced force to knock it down to either side, and the center of mass is directly along the axis perpendicular to the ground.

Anyway, I remember reading about an experiment where some scientists had an extremely thin divider, and then they shot a photon at it, and sometimes the photon went to one side of the divider and sometimes to the other. I forgot what the experiment was called but I think that was the gist of it. Scientists were unable to predict what happens. So that seems like a truly random event. But maybe you are right, Oblongato, maybe we just don't understand quantum mechanics that well.

[Giantfish]

I am assuming Oblongato is defining randomness as something that can end up with multiple different outcomes and having absolutely no preference for any of them.

While I do believe that it is not possible to make an observation that would disprove either randomness or causation, I do believe that if randomness were to exist, it would still be possible to make accurate predictions concerning the behavior of matter and energy.

Suppose for a moment that we can observe a truly random "coin flip." When we flip one coin, then there are two separate outcomes with equal chance of happening. When we flip two coins, we note that there are four possible outcomes. However, two of these outcomes are equivalent, so there are only three separate outcomes. Furthermore, if we consider because two outcomes are equivalent, we say that the three separate possibilites are not equally likely. One result, where one coin is head and the other is tails, is twice as likely as either of the other two results.

If we continue to increase the number of coin flip, reason out the different possible outcomes, and then add up the equivalent outcomes, we will find that roughly half our coins should land on heads and half of our coins should land on tails.

Now if randomness did exist in the real world and had equivalent results adding up to favor one outcome, then all we would have to do to predict what will happen is create laws that allows us to predict the most the outcome with the most equivalent results when given a situation.

On a related topic, if the laws that we have right now really are based on the most probable outcome, then we would expect that our laws will not always be perfectly accurate on any single observation. That is indeed the case that we find. Our laws do not match what happens in the real world exactly. While, human error is probably responsible for a large part of the difference from expected observations and actual observations, we do not have the ability to measure and know that the difference was not because of randomness in the system.

[Lithium]

Random can be perceived differently fom different observers. As humans, we have the instinct to observe the phenomenas around us. When we have a set of data, then we make an experiment. Not being able to get a logical pattern we say its random.


That's the one. For someone, such as a cop observing a string of murders, they might appear random. But for the serial killer, he might know the common string of the victims; to him, they're not random at all.

I don't think certain words in any written language should be taken literally ie: randomness, fate, chance. I believe they were words simply fabricated to say

1) randomness - word for an unseen or seemingly non-existent pattern

2) destiny - the belief that everything is set in stone, although it isn't. Humans probably use this word to rationalize why certain things happen, such as the end of the world.

In conclusion, randomness is not meant to be explained, but it is in our human nature to ponder upon such things. Why? Because we can. :D

RANDOM SMILIES TIME!

:_papple: :cookie::banana::cuss::samurai::twak::kiss::chair: :angel::alcoholic:chuckball

[Oblongato]

I am assuming Oblongato is defining randomness as something that can end up with multiple different outcomes and having absolutely no preference for any of them.

Yep.

While I do believe that it is not possible to make an observation that would disprove either randomness or causation, I do believe that if randomness were to exist, it would still be possible to make accurate predictions concerning the behavior of matter and energy.

Suppose for a moment that we can observe a truly random "coin flip." When we flip one coin, then there are two separate outcomes with equal chance of happening. When we flip two coins, we note that there are four possible outcomes. However, two of these outcomes are equivalent, so there are only three separate outcomes. Furthermore, if we consider because two outcomes are equivalent, we say that the three separate possibilites are not equally likely. One result, where one coin is head and the other is tails, is twice as likely as either of the other two results.

If we continue to increase the number of coin flip, reason out the different possible outcomes, and then add up the equivalent outcomes, we will find that roughly half our coins should land on heads and half of our coins should land on tails.

Now if randomness did exist in the real world and had equivalent results adding up to favor one outcome, then all we would have to do to predict what will happen is create laws that allows us to predict the most the outcome with the most equivalent results when given a situation.

On a related topic, if the laws that we have right now really are based on the most probable outcome, then we would expect that our laws will not always be perfectly accurate on any single observation. That is indeed the case that we find. Our laws do not match what happens in the real world exactly. While, human error is probably responsible for a large part of the difference from expected observations and actual observations, we do not have the ability to measure and know that the difference was not because of randomness in the system.

Actually, I think our physical laws are perfectly accurate. The prediction errors are generally the result of a too-large number of variables to track, unexpected influences of other factors or a system that is so complex we do not understand completely how it works. In such cases, we can use a probability model, but only because of the problems mentioned above.

It would be interesting to know what a model of the mechanics of randomness would look like. On a larger scale we would never dream of a situation where two pool balls hit and rebound in anything but the predictable way. On the subatomic level, where, allegedly, truly random behavior of matter and energy exists, we just can't see well what is going on. What is our model of random behavior? Is it possible even to conceive of the mechanics of randomness? I believe that where randomness exists, there can be no mechanics, for mechanics describes the rules of behavior of matter and energy. For me this is one of the largest problems with the concept of a non-deterministic universe model - it requires that a point exist where there are no rules - where there is no potential to make sense of observed behavior.

And again, how is it possible to explain the behavior of matter and energy on the level above the supposedly at-least-partially-random subatomic level? If there is random behavior below it, how can there be a foundation for predictable behavior on the next level, where the behavior of matter and energy is more or less completely predictable? Could it be that the predictability of the behavior of matter and energy on the super-atomic level is evidence for the existence of physical laws that extend beyond the reaches of our observational powers?

[TheBB]

I think you guys are mixing randomness and determinism (or nondeterminism, really). They're two different things.

It's possible to have random phenomena in a deterministic universe. Randomness, as is hinted at by some people here, is perceived differently according to point of view - or rather, according to information.

I wish I had a good example now. I'll get back if I can think of one.

By the way,

I am assuming Oblongato is defining randomness as something that can end up with multiple different outcomes and having absolutely no preference for any of them.

Random variables can have arbitrarily high preference for some outcome. Random variables without preference are called uniform, but there are many, many more, and they're all random.

Consider a loaded die. It might show 6 more than 1, but isn't it still random?

[Oblongato]

The fact is, true randomness (as opposed to the use of the word random to refer to behavior we cannot predict because we cannot keep track of the variables) is possible only if causation breaks down, i.e. if physical laws break down. This semantic distinction between the two definitions of the word "random" is an essential aspect of the discussion of determinism.

Random variables can have arbitrarily high preference for some outcome. Random variables without preference are called uniform, but there are many, many more, and they're all random.

I need to revise what I said previously. Even if there is a preference for one particular outcome, if that outcome cannot be predicted, it is still random.

The question, then, is whether we are talking about seeming randomness (it is theoretically possible to predict the behavior of matter and energy if all underlying variables are known and can be monitored) or true randomness (it is impossible to predict the behavior because there are no variables and there is no cause - the behavior just happens).

I am arguing that the former is true, and the latter cannot be reconciled with the fact that there is behavior of matter and energy in the universe that we can predict.

If the underlying behavior were truly random and the level above it were caused by the truly random behavior, the caused behavior of the level above the random level would also be random, and this randomness would be passed on to each succeeding level, resulting in a completely chaotic universe. Since we are able to perceive order and predict the behavior of matter and energy at higher levels, the existence of true randomness at any level would be ruled out.

In fact, if a layer of randomness were inserted into a system that is otherwise caused, the randomness would render everything above it chaotic.

We can more or less perfectly predict the angle a pool ball will move in when struck if we know the angle of the ball that strikes it. If we inserted a pool ball with random behavior between the first pool ball and the second, the behavior of the second pool ball would also be completely random. Nothing after the random pool ball would be predictable.

It's possible to have random phenomena in a deterministic universe.

Only if we are talking about seeming randomness.

[TheBB]

Only if we are talking about seeming randomness.

Which we are. Otherwise we would be talking about determinism...