Why do things collide?

[Story]

Why is it that objects, for the most part, must collide in order for effects to occur?

There are phenomena that occur without any collision, such as gravity, radioactive decay and the polarised spin pairing of leptons in quantum entanglement, but for the most part, why does collision cause effects to occur?

I ask this because I'm trying to understand if we think that it makes sense for collisions to produce effects because we see them do so or if we see them do so because it makes sense.

What things other than collisions could cause things to be? And if something happens without the involvement of any collision, is it causeless?

 

[ArthurWilborn]

Why is it that objects, for the most part, must collide in order for effects to occur?

There are phenomena that occur without any collision, such as gravity, radioactive decay and the polarised spin pairing of leptons in quantum entanglement, but for the most part, why does collision cause effects to occur?

I ask this because I'm trying to understand if we think that it makes sense for collisions to produce effects because we see them do so or if we see them do so because it makes sense.

What things other than collisions could cause things to be? And if something happens without the involvement of any collision, is it causeless?

Collisions generally cause things to happen because it's a common means of transferring a relatively large amount of energy between objects. Other interactions, such as the ones you mentioned, are usually caused by fundamental forces.

 

[KnowingLaughter]

Hey Story!

Forgive my over simplified answer if you could, I am an artist rather than a scientist but I have a possible idea.

Some things have an area or range of effect (radiation, magnetism) that has influence outside of the matter they are comprised of. This allows them to have an effect on other things without physical contact of matter.

However when thinking of radiation, light etc. it is easy to think of an area of effect, but (and please somebody correct me if I am wrong!) the effect that they have on things is actually due to waves or particles colliding with matter. So even at that level collisions are occurring.

Other things are relatively inert and the only seeming way for them to influence another would be to interact with it physically. Two balls for example in a snooker game. (I am ignoring gravity here as everything is subject to its force.) The only way for these inert things to interact (transfer energy for example) is physically.

It seems to me that "motion > attraction > collision > resultant change or annihilation" is the universe's way of getting things done but I know I am over simplifying this!

What things other than collisions could cause things to be? And if something happens without the involvement of any collision, is it causeless?

I think the "four forces" would count: Gravitational, Electromagnetic, Weak Nuclear and Strong Nuclear.

Personally in answer to your second question in the quote, I don't believe so. I think that by virtue of something happening it is safe to assume it had a cause. We don't always yet know what it was of course!

Also, why assume that collision is the cause and not the result of other effects (gravity for example)? Please don't think I am criticising, I just love to hear different viewpoints!

Personally I see things in a causal way like this: cause >> effect ( is now cause ) >> effect ( is now cause ) and so on, so I find it hard to see any interaction as one or the other, rather than both.

I ask this because I'm trying to understand if we think that it makes sense for collisions to produce effects because we see them do so or if we see them do so because it makes sense.

I think it makes sense to assume that interactions produce effects - whether by collision, attraction, manipulation or any other means. In that sense everywhere above that I wrote "collision" I personally feel should be written "interaction". Collision being matters favourite way of interacting!

 

[Master_Ghost_Knight]

I profoundly disagree with everything, that is because I have a greater insight on what exactly is going on that I didn't had a couple of years ago, and I could have never imagined the way things really are because it is extremely non-intuitive. All actions are at a distance, just like gravity, only some of the effects acumulate so you can see them interact from far away while others tend to cancel eachother out that the gap between the interacting parts is to small for you actualy being able to see.

I bet you are probably siting on chair (if you are not please do so), and the force that prevents you from falling trough your chair and continue way down to the earth's core is the same force that allows your computer to work (the electro magnetic force). The atoms that composes your body are themselves made out of positively charged protons in the nucleous and the same ammount of negatively charged electrons (which for now only requiers not to be in the same place as the protons), because the atom as an all is essentialy neutral and the protons and electrons are so close togheter, at a certain distance it is almost as like the atoms have no charge at all. But if you are close enough that gap between the protons and electrons makes a difeerence enough so it produces the radical response that we precieve to be in a generic sense "contact". It is almost like the oposite effect of being sucked by the gravity of a planet while traveling trough space, only in extremely shorter scale. The electromagnetic force is very very strong compared to gravity, but they prety much work the same way, they just happear to be radically different due to the arragement in which we experience them (i.e. gravity is weak but can only acumulates, while electromagnetic is strong but can be canceled out).

 

[Aught3]

I was going to say something similar to MGK, everyday objects are not solid but are composed mostly of empty space. It's not a physical collision that occurs but an interaction between the electromagnetic forces of the two objects.