Randomness Definition and 136 Threads

Found this question while think of determine&random. If a system if very complex, it may looks like random. Even GUT is found, it is still impossible to tell what a determined system will be after a long period because of Heisenberg's uncertainty principle. An error in initial conditions, even...

Hi everyone! I have two questions about radioactive decay that some of you might be able to answer (I'm a mathematician and no physicist by the way). The first one is very general: As I understand it the time at which a single instable atom decays is believed to be a truly random process. But...

Hi everyone. It's been years since I've done any stats, so I need a bit of help, please. I want to include it in a blog post I'm going to do (not here on PF), so I don't want to give away too many details :p I apologise for my terrible understanding of stats, please be patient! Anyway, over...

Hi, I've got a distribution of points in two dimensions and would like to demonstrate if these are randomly distributed. The points have been measured using single particle tracking, so likely have some degree of error in their position. What I'd like to show is whether, as time progresses...

Greetings, I'm not sure if this site, or this area of the site, is the most likely place for me to get an answer to the question I am about to ask - so if anyone reads the question and doesn't know the answer, but knows of a more likely place for me to get an answer, please let me know, it...

maybe this is too basic question but it is not so clear for me. when we refer to a random experiment, can a phenomenon be absolutely random by itself or its all about our uncertainty about the outcome that we call it random?

Let's say we randomly select integers to construct a potentially infinite number, for example 3588945... There is a non-zero chance that eventually we will obtain any possible finite series of numbers, say a billion 3's in a row. It is known that pi is indistinguishable from a random series of...

hi folks, the last couple of times I've been on here have been extraordinarily useful, and i have a new challenge that I'm stuck on so thought i'd ask. this one takes a bit of explaining, apologies. i've encountered an issue with a standard cryptographic algorithm. take a block of data (say...

Hello, Sometime in the last 6 months I read that researchers analyzing data from the decay of a subatomic particle and reported that the decay appeared to be random or unpredictable. I recall they said this particular reaction was very low level. This would have been in either Science, Nature...

In decoherence.. it is said that it is in an improper mixed FAPP (for all purposes) which is the same as collapse. Are you saying that decoherence is deterministic and not random (probabilities)? Random or probabilities only occurred in proper mix? Why. Is it not possible to calculate exactly...

I have seen some controversy among this question and would very much appreciate it if somebody is able to give a good straight answer (if possible) with some proof to back it up. Does true randomness exist in the universe at a subatomic, higher or perhaps lower level? This is in perspective...

This is a very important question for me which has bothered me greatly. I started talking about it in the Smolin cosmic natural selection thread. What I would like to know is, if the Universe started over a very large number of times (n) from t=0, the start of the big bang, In how many of these...

I'm posting this here because it's neither fully statistics or biology, and I have no technical knowledge of statistics. It's well known that humans have trouble behaving truly randomly. If a group of people is asked to choose a random number between 1 and 10, each person is very likely to...

Disclaimer. I am a PhD level neurobiologist, and like most of my peers a crappy physicist. I went back to better complete my scientific understanding and just on my own am giving physics a crack as a curious adult, and in the process I have gotten hooked on the beauty of physics. I am working it...

What is the relationship between a-causality and randomness? Let's look at the argument below: For something to be (truly/inherently) random there cannot be a cause. Because, if there is a cause then the cause can be studied and the result/output can be predicted and hence there would no...

"Average Randomness" Thought experiment Please bear with my explanation, I am, by no means a Physicist. During a recent theoretical thought experiment, I thought of a strange factor that I feel I should let out before it becomes forgotten by the constant wave of thought experiments that flow...

Hi All, How do we tell the difference between something being random and something being deterministic but unpredictable because of limitations without with our tools/technology or methods of knowing (e.g. uncertainty principal)? Are there cases where we cannot tell the difference? For...

if a nucleus decays at random, it should be impossible to effect that in any way and if observered, you are effecting something that is by definition supposed to be random. for example if i am a particle and have true randomness, then being observed at certain intervals, probability would...

not to be impolite, but i truly view randomness in reality as something you can trick your kids into accepting along with santa, the tooth fairy etc. when compared to causality the idea of true randomness existing in reality seems incredibly weak to me. is there any logical way to...

not to be impolite, but i truly view randomness in reality as something you can trick your kids into accepting along with santa, the tooth fairy etc. when compared to causality the idea of true randomness existing in reality seems incredibly weak to me. is there any simple logic which can...

I'm trying to at least understand what decoherence can and cannot explain about how quantum mechanics works, the more I read, the less clear I am about what is known and what is merely speculative. So I finally decided the only way to get any further was to try and clarify what I think is...

Electrons appear randomly in quantum physics, but are there any other places where particles behave randomly, is there any other true randomness in the universe, something we can not predict?

I started this thread to continue a conversation from another thread. Does HUP imply randomness? What really is the definition of randomness? I would say that HUP does not imply randomness, but just tells you the relationship between how the state vector is spread out along the basis of two...

Is it yet possible to have an equation whose output is completely random? I know that programming random numbers on a computer is based on a seed (a current time stamp), and is not total random though it is sufficient for the job. I was thinking that if it were possible to create a...

I'm womdering if real quantum randomness is important for evolution to work. In a universe without randomness i.e. where the future is predetermined, the amount of information contained inside the universe would be constant. No matter how old it is, the information content of the universe would...

The Oxford English Dictionary defines 'random' as: "Having no definite aim or purpose; not sent or guided in a particular direction; made, done, occurring, etc., without method or conscious choice". However, if we intend randomness as events with equal frequency probability this can't be. Think...

Suppose I have a true random number generator. It generates a string of 10 numbers. I then look at those numbers. Are they still random? If no then why, and would they be random for a bystander who did not see the numbers? If yes then consider this. I am an omniscient being. This same random...

Weak measurement show that you can get "partial/probabilistic" which-way info and get a "partial" interference pattern. Deduction 1: Does this mean that weak measurements prove that we can control the degree of randomness? (either of individual photons or average of a thousands of photons)...

I've recently been having a discussion with someone about whether it is accurate and meaningful to describe the random behavior of quanta as "supernatural". The origin of the word comes from "supra-natural" meaning above and beyond the laws of nature which certainly fits the description of the...

According to Nick Herbert in Quantum Reality: "Even if we believe (with the support of Bell's theorem) in universal superluminal links, we must face the possibility that such links are private lines accessible to the workings of nature alone, and are blocked to human use by an undecipherable...

I'm trying to get my head round this. I don't see why our inability to measure the world around us means that at the quantum level things must be random. I understand that measuring momentum of a particle to a high degree of accuracy means losing accuracy in it known position. But I don't...

Hello all, Please excuse my naive question that follows. I do not have much experience in Statistics and need to obtain a set of variables which assures randomness in the variables. From central limit theorem, I believe addition of random independent variables assures randomness of the...

Homework Statement 1. A bus arrives at a station every day at a random time between 1:00 PM and 1:30 PM. a) What is the probability that the person has to wait exactly 15 minutes for the bus? b) What is the probability that the person has to wait between 15 and 20 minutes for the bus...

Hi, everyone: I am trying to prepare a class for tests of randomness. I am trying to use as output, the 6 numbers of an (actual) lottery. Would a test of runs of the means of the winning numbers be effective here? I am thinking of selecting, say N=50 consecutive...

I will give it a try: Randomness appears to be the descriptive complexity of a data structure such, that description of the structure takes more bits of information than what appears to be contained in the structure itself. In that respect, we live in a random world due to the inability...

hello guys. What does true randomness mean Is it that you cannot predict the next number in the sequence ? Can repeating of numbers take place ?

Does quantum randomness or uncertainty tells us that we have free will?

I was reading the book "the grand design" by stephen hawking and I reached the part about randomness and Heisenberg's uncertainty that I didn't understand. The book seems to suggest that "Probabilities in quantum theories reflect a fundamental randomness in nature". The thing seems right to me...

Help! I can not catch meaning of: 1. random event 2. random number 3. random process

It isn't supernatural, is it?

I've searched these forums hardcore about these questions and the wide range of answers is so confusing to me, so I hope that maybe if I provide some examples and specific questions, I may better understand. I always hear that quantum particles exhibit "intrinsic" randomness in the states they...

Hello, all -- I feel as if I've only really been exposed to classical physics thus far, and I want to educate myself a bit further. What really puzzles me the most is the concept of randomness, which I've always attributed to an inability to measure all variables involved with the outcome...

If you have played games of chance, you may have seen rolls of the dice, or flops of the cards that did not strike you as being random. I have played many games of backgammon, where the roll of the dice trumps talent. You can be bearing your checkers off, and lightning strikes. You get hit...

I understand decay is truly a random process approximated by half-life. So two particles that appear similar to us in every way will experience decay at different times impossible for us to predict. Are there any theories that explain some underlying process that dictates this action. Even...

Hi everyone, I'd like to start by saying that I have no background or knowledge of maths other than high school. As a consequence, I have no idea if this question is stupid, trivial, nonsensical or whatever. I also don't even know if it's in the correct thread (I made the best guess I could). So...

Hi, I have a question which I've been pondering over and would like to have an anwser to. I'm not schooled in physics so I may be using bad terminology which you're welcome to point out of course. Anyway my question mainly has to do with the randomness in quantum physics. I know that the...

the subject is all there is to it. I mean, is randomness a provable property of the integers? can there be such thing as a random integer? to me it seems no IF the "one way function" theorem is disproved. at the same time, what about those wacky isotopes from half lives, ie schrodinger. what's...

If I fire photons at a glass, some will be reflected back and some will go through. Which ones is by deifnition random, sincee all photons are exactly alike. Is this correct?

"True' randomness cannot be generated by any efficient algorithm (Kolmogorov) while pseudorandomness can be, such as the apparently random digit sequences of irrational numbers. The experimental realization of quantum states is taken to be an example of 'true' randomness in nature. However, if...

I have often thought that 'true' randomness and free-will are similar in the sense that neither require previous state dependence, but both do require acting as their own 1st cause. The question is: How then might someone talk about either existing, without being led into paradoxes...