Hello,
I was just wondering if random exists within physics.
If not, if there's only one way something can happen depending on how it happens, and future events are determined by present and past events.. then surely the future can't be controlled.. it could only happen that one way.
Is choice an illusion?

Is choice an illusion?

If we have no choice, we're "living" our lives just to entertain someone who has created us to entertain them, and has decided for us what will happen to us. It is a matter of how you think of it. You might try to prove that you really have a choice by saying: i'll close my eyes now...i'll keep them closed for 2 seconds, then i'll open them. It would be your free choice of doing that. But someone might argue that it wasnt truly your choice, but that it was "written in stone" that you will close your eyes, keep them shut for 2 seconds and then open them. But as soon as they say that, try pointing a gun at their head and ask them if it's written that you'll kill them or not. They'll tell you it all depends on you. So they'll soon prove you DO have a choice.

Lets say that events D + E happen as a result of event C, and C happens as a result of events A + B.
If A + B didn't happen in that exact way, C wouldn't have happened as it did.
A small change like this would then go on to cause a larger change, as everything relating to the event change after it wouldn't happen as it would have done before.

If psysics isn't random, then that can't happen.. every event from the birth of everything only has one way that it can occur. So nothing about the futre is random either, it will all happen the only way it can (assuming no outside inffluences such as a god intefere). We are no exception to physics, we follow all the rules, so all the molecules, energies in our bodies are reacting/moving the only way that physics allows, so although it may feel like choice exists, it is merely the events that occured before the event that cause thought to happen in a certain way, the only way it can.

Everything you said is true IF we suppose that previous events determine future events. And if previous events determine future, then it's equal as saying: "Future is already written for us."

You also didn't state that "for each event B, there must be an event A that is causing it". If you don't state that, then it means that there exists an event B that will happen and will not be caused by any previous event A. That means that there actually are random events. On the other hand, if you state that, then you stated "future is already written". Then you have nothing to prove. You just stated there is only one future, and then try to prove it. You cannot do that. You have to prove that all events B are caused by some events A. If you prove that, then you proved there is only 1 future for all of us, prewritten, and you will actually prove choice is only an illusion.

if you pick any one point in time, the entire future depends on that moment, and also any point in time of the past. what happens there sets off what will happen, even what every human shal do according to how they llready and and how they will react to there environment, every thought ever event everything is going to happen a certain way no matter what. this means we can not change the futer. but we do creat it. and the thing with the gun, it depends on the past, if they had or didnt have a gun for example, or the though patterns that lead them to decide to use the gun in such a way-it does not depend on the one holdnig the gun, but what happened to make them hold it

Classical Newtonian mechanics assumes no randomness- everything is controlled by simple equations of motion, and that's the end of the story. However, in modern physics we have a key concept called the Heisenberg Uncertainty Principle, which states that you can never truly measure both an object's position and momentum with total accuracy. Hence it's impossible to predict with total accuracy how one particle will affect another. This effect is most pronounced for objects at the atomic level, but the effect on the real world is profound. The way that molecules in a gas interact, for example, can only be modeled as random.

Think about this experiment that shows how randomness is present in every day life - suppose you line up 10 billiard balls, with each ball separated 1 meter from the next. Using a cue ball, is it possible to hit the first ball into the second, so that the second hits the third, the third hits the fourth, and so on for all ten balls? It sounds simple enough - just a very good combination shot. But if you do the math you'll see that any error in the way two balls collide is magnified by about a factor of 30 when the next ball is hit. So for ten balls any initial error is magnified by 30^10, which is about 6 x 10^15. Stated another way, the initial hit would have to be accurate to better than 5x10^-15 cm. To achieve this level of accuracy the balls would need to be smoother than atomic structure allows. At this level the Heisenberg Uncertainty Principle sets in. So it's impossible to predict exactly what will happen to the 10 bals - the end result is random. Now think just how much more incredibly complicated the universe is compared to just 10 billiard balls, and you can see that randomness is indeed fundamental to how things behave.

random is just a concept...
think about programming...the function random is not so "random" ;) ...in fact it acts randomly as it is programed to act; yes we can say there is random as long as we cannot predict or know the result, but in fact if we could know that there will be random no more...
As a matter an A point can determine a B point to act like "that" because the A point was programmed to act like that...so the right question is there is something or nothing ?! and if there is something...why and how did it appeared? and of course there might not be any need to justify the existence of something as long as it does not exist or it is not defined...