Does randomness exist?

[endless_dark]

Recently I became very interested about philosophical and science deep matters (I wish I didn't, but there is no turning back), anyway, now I'm reading a book written by Stephen Jay Gould about evolution of species, and uses something he calls, the Time Tape.

 

The mental experiment is this way, assuming that you can rewind and fast forward time. If you went back to the first steps of life, and press play, would the human being appear? He claims that maybe not, because it's quite possible that evolution was a random process.

 

But know I think about randomness, looking at it from my perspective (I am a computer enginereen student), as far as I know, a computational device can't generate a real random number, the randomness in computers is product of a function using things like the date. So for computers, randomness is impossible.

Now we move to the real life and think in something random, like rolling a dice or tossing a coin. It will depend on certain variables, maybe thousand of variables that we don't know. But if we could recreate the same scenery, we would get always the same results.

 

Trying to think in another random stuff, someone can say that humans are random and unpredictable, but I am personally quite convinced that a human is no more than a computable device made of biological hardware. So I think it's aswell governed by a HUGE quantity of variables, things like, what a person has eaten, the things he heard or watched would change those variables that make him do the things he is going to do.

 

Briefly, those things make me think that everything it's predetermined and everything makes part of a chain, and we could follow that chain to the origin of time.

 

On the other hand, science has supposely found the real randomness in quantum physics, but I haven't completely understand this issue.

 

What do you people think? Is there real randomness?

 

P.S.: Sorry if my english is not correct

[Bignose]

quantum mechanics seems pretty random at its base. There may be deterministic sources underneath that we haven't discovered yet, but QM seems pretty random at the moment.

[cameron marical]

its impossible for computers to be random, right?

 

what about us, can our brains have any random sequences?

 

is randomness even real?

[stereologist]

A digital computer can be random. There are security devices built to generate random data. The random data is not a digital function, since patterns in digital functions can be determined by viewing enough of the output and knowing the process. This was exploited by hackers who hit an online gambling website that used a poor random number generator.

 

The security devices rely on analog input that is digitized.

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The other thought I had was the definition of randomness. It is used in many different ways by people. There is a nice introduction in Kendall and Moran's book in which they solve a problem using 3 different random definitions and get 3 different answers.

 

Is there a chain to follow?

 

It was a popular thought back in the 1700s that the world was decidable and that the advances in math were the tool to understand the deterministic nature of the world. It may have been LaPlace that was giving a lecture to Napolean on the new mathematical discoveries. When asked where God fit into this scheme, LaPlace answered that God was an extraneous hypothesis.

 

Since that time the certainty of a deterministic world has been shaken by the notion that the most basic events in the world are in some sense random.

 

There are many events that can be described well by using the concept of randomness. Descriptions of physical processes such as pressure in liquids, and radioactivity are well described using randomness.

 

Is there real randomness is a philosophical question. Does it make sense to assume randomness in some situations? Yes.

[Bignose]

is randomness even real?

 

Randomness can certainly be defined mathematically, so in that sense, randomness is real. And there are several situations in real life that while maybe not random at the micro level, at a macro level can be described very well by random variables.

 

Turbulence in fluids, the agglomeration/flocculation/breakage of oil droplets, the dispersion of fine particles/droplets, the birth and death of a large population of cells, the precise arrangement of atoms in an alloy or zeolite are just a few that I know of. I guarantee that there are many more I can't think of.

 

And that doesn't include all the "traditional" ones like rolling some dice or shuffling cards. Yes, while the process of shuffling and rolling dice can be deterministic if every variable is accounted for, these can be made random if you intentionally don't account for every variable.

 

Like I said with QM, it may be possible that truly deterministic processes may be found for all of these, but again at a macro level, all can be described very well with random variables.

 

There is a whole branch of mathematics called stochastic calculus that deals with the processes of random variables.

[lucaspa]

The mental experiment is this way, assuming that you can rewind and fast forward time. If you went back to the first steps of life, and press play, would the human being appear? He claims that maybe not, because it's quite possible that evolution was a random process.

 

But know I think about randomness, looking at it from my perspective (I am a computer enginereen student),

 

What you need to do is look at "randomness" from the pov of an evolutionary biologist. You are tying yourself into knots because you are using the term differently than Gould uses it.

 

In evolutionary biology, randomness means "random with respect to the needs of the population or the individual. In a climate getting warmer, just as many deer will be born with longer fur as shorter fur. Selection is nonrandom, and the shorter furred deer will do better and be selected.

 

Gould was also talking about contingency in evolution. There are usually several different designs that will do the job. For instance, each species that uses oxidation for energy has its own cytochrome c protein that is essential in getting energy. By "own" I mean a cytochrome c that has a different amino acid sequence. Yet they all work equally well.

 

So, why 4 limbs instead of 6 in vertebrates. Contingency. The variation for 4 limbs appeared first in vertebrates. Why did intelligence evolve in mammals instead of dinosaurs? Contingency. An asteroid hit earth 65 million years ago and wiped out the dinos. If it had not, sapience might well have evolved in small theropod pack hunters like the raptors.

 

Gould is saying that, if the history of life on the planet were repeated, our particular physical form-- that of a modified ape -- would not have appeared. Sapience would probably eventually appear as natural selection explored possible genomes, but our particular genome would not have happened.

 

In terms of randomness, from what I have read individual events on the quantum level are random. In large groups they are regular, but not the individual events. For instance, with 1,000 atoms of C14, 500 of them will decay in 5,280 years (a half-life). But which atoms will decay is "random". After all, all the C14 atoms are identical so why would 1 decay 1 second from now and the one adjacent to it not for 5,000 years?

 

As an experiment for an engineer, you could hook up the controllers to a computer mouse to a liquid scintillation counter and place a solution containing C14 in the counter. The counter has photoelectric sensors at perpendicular to the axis of the vial and each other. So you could connect one to the vertical control to the mouse and the other to the horizontal control. The movement of the mouse would then be random.

[thief]

Thief here...

It's been about a year since I saw the demo...please forgive the lack of reference.

 

The demo was simple.

Choose three points on large paper....and a forth point inside the triangle.

Label the corners one thru six.

Grab some dice...throw one cube away....roll the remaining cube.

 

From the fourth point, measure halfway to the corner chosen by the cube.

Make a point there. Roll again. Measure halfway to that corner from the second point. Continue.

 

As you do so, a pattern will form. Congruent triangles. Overlapping, and various size, but all having the same proportions as the original boundary.

 

The science program was announcing the new science of Chaos.

 

Numbers can be difficult to work in this new study.

Try calculating the flight of a dandelion seed.

But random events can repeat, and the repetition is what counts...even though the numbers don't work well.

[the guy]

i can prove that randomness exists. just have a chat with me when im drunk.

 

on a serious note though, i don't believe that randomness exists. take the filght of a dandelion seed, it would be controlled by all the insanely large number of things that happened around it at the time and a long time before. if you had powers of god and created a world which had happened exactly the same as the last up to the point were the dandelion seed was about to fly and then let it happen, it would happen the same.

or so it seems in my mind.

 

but now i think differently. because i just thought of something. see what you think of this:

if you took a baby and put it in a room and then paused time. you then once again used your god powers to create a parralel universe in which everything was the same and had happened the same until now. the baby in this room has had exactly the same experiences and every little neuron and whatever in its brain was the same etc etc etc and then you started time once more, would the baby do the same thing as in the other world?

one part of me says yes the other says no. i cant decide. what do you think?

 

ahh i'm really confusing myself now :s

 

btw i know this is not possible stopping time and all that but just for the sake of this imagine that you are god and you can. just like that. ZIP! the leaning tower of piza was never built and consequently the whole world is a different place! ZIP! time never existed. woops. nothing here. um. ZIP! a sheep has been elected president of the united states and has unknowingly declared war on russia! BING! bartholemew the frog has undergone laser eye surgery in his toe.

oh got a bit carried away there. sorry

[Kaeroll]

My view (and it is just that... I don't claim any truth or evidence for this viewpoint) is that randomness exists to a point. The probabalistic nature of QM suggests it does. So to answer the scenario posited by 'the guy':

if you took a baby and put it in a room and then paused time. you then once again used your god powers to create a parralel universe in which everything was the same and had happened the same until now. the baby in this room has had exactly the same experiences and every little neuron and whatever in its brain was the same etc etc etc and then you started time once more, would the baby do the same thing as in the other world?

one part of me says yes the other says no. i cant decide. what do you think?

If we made an ensemble of babies in boxes to find the average behaviour over an effectively infinite number of identical babies, I think you'd find different behaviours with different probabilities, determined by the mass of complex interactions at the atomic (and sub-atomic) level - which are random but guided.

[thief]

Thief here...

I think you're overlooking something.

Repeated action produces predictable results.

It's not the science of numbers that so many people favor.

But because the results repeat...then some are willing to say..

Chaos is science.

[Vortigon]

I personally don't think randomness really exists.

 

When something is called random, I think were really saying that we don't have all the information concerning a certain event or process to understand what happened or what will happen.

 

If we were able to know everything completely and know all of the interactions concerned with a process throughout the entire Universe all the time then I think that we could theorectically predict any outcome to any process or event.

 

Of course it will be impossible to ever aquire all the information about every event in the universe in real time as it occurs that may be effecting a certain process or event but theoretically if we did know 'everything' then randomness would not exist in my opinion.

 

Even the apparent randomness of quantum mechanics I feel is just our lack of understanding, we may of course never have enough knowledge or ability to aquire enough information to predict any particular single quantum event. But if we did have 'ALL' the information about a quantum event then it's randomness could be predicted. Scientifically we just haven't reached that level yet and may never reach it.

[jimmydasaint]

I am just a simple minded man but is it possible for true randomness to select the Laws of Physics, setting them to finely tuned limits, e.g. the force of gravity or the speed of light?

[thief]

Thief here...

Before we start doing a lot of numbers....

Let me point out that equations lean toward exact results and therefore

exact predictions.

Random events don't have that quality.

Randomness deals in probabilities.

If you can..... equations that demonstrate probability might work.

But, equations having exacting quantities and results..... 'probably' won't.

[Bignose]

Thief, there is a whole field of mathematics -- stochastic calculus -- that is the calculus of random variables. They are "exact" equations written for variables that involve randomness.

 

For that matter, even saying x is distirubted normally with mean 0 and variance 1 has an exact definition:

 

[math]p(x)=\frac{1}{2 \pi } \exp(-0.5x^2)[/math]

 

This equation is the an exact mathematical formula for the distribution of samples of x. So, you need to be a bit more careful in explaining exactly what you mean, because the mathematics of probability, statistics, and stochastic calculus is very rich and very well defined.

[thief]

Thief here....

That a mathematical technique has been developed does not indicate it's ability to predict an exact result.

Can your equations plot the path of dandelion in flight?

Can you be sure the landing location?

 

This is what random events are about.

Numbers don't apply to everything.

[Bignose]

And I never said it did, thief. The equations can predict the most probable location of where the dandelion seed would fall, however, or the region where 95% of the seed will fall. And that's pretty powerful, really.

 

Part of it is in your use of the terminology -- because when you write "exact" that has different meanings. That p(x) equation I wrote above is exact in that p(x) is exactly the probability density function of a random variable that distributed normally with mean 0 and variance 1. It doesn't --- and doesn't claim to be able to -- predict what any single value of that random variable will be. It predicts what a large number of samples from that random variable will be. And that's it.

[thief]

Thief here...

Defend your equations as you care to.

The topic is...does randomness exist?

Yes.

And that's it!

[Vortigon]

The path of a dandelion falling could be predicted 100% of the time with the right information at hand.

 

Therefore it is not a random event.

 

If with enough information an event 'could' theoretically be predicted then I wouldn't consider it random just hard to know.

 

If you know all forces at work on the dandelion at all times then you would know exactly where it would land.

[cameron marical]

Well said Vortigon.

[Bignose]

The path of a dandelion falling could be predicted 100% of the time with the right information at hand.

 

Therefore it is not a random event.

 

If with enough information an event 'could' theoretically be predicted then I wouldn't consider it random just hard to know.

 

If you know all forces at work on the dandelion at all times then you would know exactly where it would land.

 

Maybe, maybe not. Again, we just don't know. Turbulent fluid motion is random down to very small scales -- small enough that the random fluctuations of the atoms themselves could be having an effect on macroscopic turbulence quantities. And, as near as we can tell, those fluctuations as describes by Brownian motion are indeed completely random -- perhaps as a quantum mechanical effect.

 

If someday we figure out that QM is deterministic, then maybe, but at the moment, the best information we have is that QM has a strongly random component, and that the exact result for a single event is unknowable -- all we can talk about is what happens over a large number of samples.

[cameron marical]

Is not randomness to the contrary of Newtonian Mechanics?

 

For every action there is an equal opposite reaction...

[TheMathGuy]

Part of the difficulty with the discussion of whether or not randomness exists is the problem of defining just what, exactly, randomness is. It's not as simple as it looks. Let's say you have a binary sequence. Perhaps you'd like to define this sequence as random if there does not exist a mathematical formula for determining the next bit in the sequence given the previous bits, but every sequence encountered in real life is always finite. And given a finite sequence, it is no problem to construct a formula that describes every bit in the sequence. Just make your formula sufficiently large, and presto! And if you think you have a formula that works, and it gets the next bit wrong, that doesn't necessarily prove the sequence is random either. There may always be some other formula that would have gotten it right.

 

The probabilistic model is simply the last mathematical model that we have to resort to when we can find no better model (or modeling it deterministically would be infeasible) and observations lead us to have a reasonable degree of confidence that the distribution is uniform. But even the randomness tests themselves are subject to question. Just because these tests don't find a pattern doesn't mean there doesn't exist a test that will.

 

We have in our heads this intuitive idea of "randomness" as being without pattern. But what kind of "pattern" are we to allow here? Could not the data itself be thought of always as a "pattern", just perhaps a highly complex one? "True randomness" is unfortunately not even a well-defined concept, which we would need to have if we can ever hope to have a meaningful discussion on whether or not "true randomness" actually exists.

[thief]

Thief here....please see post seven...this thread.

 

Random events repeat, and many people are using numbers hoping to get a better handle on this item.

 

It's the repetition that generates the patterns.

In regards of post seven....you could take the roll of the dice....and the pocket scale for the measure....replace them with your own choice of corner..at random...and replace the measure with a drafting divider.

The demo will take longer....but the results will be the same.

Triangles will appear without numbers.

[Bignose]

Part of the difficulty with the discussion of whether or not randomness exists is the problem of defining just what, exactly, randomness is.

 

I think you have this backward, it is very easy to define randomness.

 

Let x be distributed uniformly across the set (H,T). This would represent a truly fair coin.

 

Or let x be distributed across the set (1,2,3,4,5,6) which would represent a truly fair 6 sided die.

 

Or the previous example of the normal distribution -- a random variable doesn't have to be uniform to be well defined -- it just needs a definition that obeys some regulations (like the integral over all values has to have a total of probability of 1).

 

From these definitions you can work out all the properties you want about these events.

 

No, again, I think that it is fair to make comments how there is no such thing as a truly fair coin, or a device that would be able to act as a truly fair coin flipper, or a fair die or a fair die roller. Or a be able to write a computer program to truly simulate random events. etc. etc.

 

But, that doesn't preclude us from being able to define a variable that is truly random. The definition exists, and it is a solid definition. The definition isn't the problem -- it's the applicability of the definition to the real world

[thief]

Thief here...

I think you've got it backwards.

 

We seem to agree that random events do exist.

But the events don't need numbers or explanation.

 

The dandelions, the ocean waves, the rain and wind, the flight of the insect...

the long list of such things....were all doing just fine...long before numbers were invented by Man to help him reason about such things.

 

That we try to make our world more controlled is natural.

Man was made to subdue all things.

Equations help him do so to some things.

It is ironic that same goal, will elude us.

No matter how many equations you have.