Is the Uncertainty Principle affected by the number of particles in a system?

[ArmenianG]

To my understanding Heisenberg Uncertainty Principle, states that we do not exist due to the fact that atoms("what we are made of") are not present, when they are not consciously observed. Please elaborate.

 

[DrChinese]

To my understanding Heisenberg Uncertainty Principle, states that we do not exist due to the fact that atoms("what we are made of") are not present, when they are not consciously observed. Please elaborate.

Welcome to PhysicsForums, ArmenianG!

Your statement is not in accordance with the conventional reading of the HUP. The HUP says that you cannot know simultaneously, to unlimited precision, what is called non-commuting observable properties of a particle (or particles). An example would be knowing both the position and momentum of an electron precisely. This principle has been experimentally verified in thousands of experiments.

It does not say that *particles* do not exist when they are not observed. A closer reading would be that unmeasured particle properties are not well defined. This is a purely quantum phenomenon, as classical objects have such properties at all times independent of observation.

 

[phinds]

To my understanding Heisenberg Uncertainty Principle, states that we do not exist due to the fact that atoms("what we are made of") are not present, when they are not consciously observed. Please elaborate.

Just as a general rule, when you hear something about the macro world (outside of black holes) that seems nonsensical (such as your interpretation of the HUP) it's likely wrong.

At the MICRO level, lots of stuff is nonsensical --- but RIGHT.

 

[homeomorphic]

I don't see any reason to assume there is anything special about conscious observation as opposed to "observation" as just measurement by a measuring device. This came up in another thread. I don't like the word observation at all when used in this context because it has too much of a connotation with human observation, which, I think, has no privileged place in physical law. Human observation is just another physical process.

Even the word measurement is kind of misleading because it suggests someone set it up when, actually, nature sets up lots of "measurements" herself without any human involvement.

It's just that some physical processes have a different status in quantum mechanics than others--those that result in some macroscopic classical effect ("measurement"). This is a very artificial-looking division of physical processes, but it does predict the results of experiments.

 

[ArmenianG]

Thank you

 

[Neandethal00]

Welcome to PhysicsForums, ArmenianG!

Your statement is not in accordance with the conventional reading of the HUP. The HUP says that you cannot know simultaneously, to unlimited precision, what is called non-commuting observable properties of a particle (or particles). An example would be knowing both the position and momentum of an electron precisely. This principle has been experimentally verified in thousands of experiments.

It does not say that *particles* do not exist when they are not observed. A closer reading would be that unmeasured particle properties are not well defined. This is a purely quantum phenomenon, as classical objects have such properties at all times independent of observation.

Can it also be possible that Uncertainty gradually disappear as the collection of particles increases. It is possible when trillions of particles occupy a small space, number of certain 'still unknown constraints' go up which make HUP disappear.

In the back of my mind I 'feel' our knowledge (theories) has a serious 'disconnect' between microscopic and macroscopic worlds. The reason the other thread on 'QM's statistical interpretation' is going ballistic is no one knows how/when to cross the boundary of this 2 worlds.