What happens to things that aren't ever observed?

In summary, the conversation discusses the concept of quantum mechanics and its idea that everything exists as a non-tangible wave of all possible outcomes until observation forces the collapse into a single outcome. The discussion also explores the implications of an object or the universe not being observed, and the different interpretations and explanations of quantum mechanics. It is noted that the concept of "observation" in quantum mechanics is not limited to human observation, but rather refers to measurement or interaction. The conversation also highlights the lack of a standard interpretation of quantum mechanics and the importance of focusing on the probabilities of measurement results rather than trying to understand the underlying mechanisms.
  • #1
McNanners
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I'm relatively new to Quantum Mechanics (QM), so please correct me if I'm wrong at any point.

As I currently understand QM, everything exists as a non-tangible wave consisting of all possible outcomes until observation forces that wave to collapse into a single outcome, which becomes real.

Is that true so far? If it is, then what happens if something is never observed by anyone?

My guess is it would exist as a wave of all possible outcomes until an observation forces the wave's collapse into one physical outcome, just like everything else in QM. But in this case, the observation never takes place. Without an observation, nothing forces the probability-wave to "decide" on a single outcome. Now what? I figure all possibilities within the wave drop to a probability of zero percent, ceasing the object's physical existence.

Would the same apply to the universe as a whole if, suddenly, the universe could no longer support life? For example, if the expansion of the universe continues forever, eventually a point will be reached when the atoms in the universe are too far apart to support life. From that point on, the probability of life existing in the universe is 0%. Without life, there's no one around to observe anything. At that precise moment (when observations are no longer possible in the universe) every single possible outcome for every single different thing in the universe instantly drops to a probability of zero percent. With no life and no observations, the entire universe would forever be an intangible wave of possibilities, never collapsing into a physical reality. The physical universe would cease to exist, instantly becoming nothing at all.

But nothing can not exist, by definition. Perhaps this is what causes the next Big Bang? Maybe the probability of a Big Bang rises to 100% when all other possible probabilities in the universe drop down to 0%. That would mean the Big Bang serves as nature's way of keeping this balance: Physical reality must be observed to exist & Consciousness requires physical reality to exist. Like yin and yang. One can not exist without the other. Your thoughts?
 
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  • #2
In the conventional view of quantum mechanics, the "collapse" of quantum states has nothing to do with consciousness/intellingent observers. Analyzing a system that doesn't collapse at any point is actually simpler, as it's behavior is simply a solution of the time dependent Schroedinger equation.
 
  • #3
An "observation" in the QM sense is unrelated to life. The physics of the universe did not suddenly change upon the advent of life.
Yes, with an observation, there a QM system will not collapse - it will remain wave-like.
 
  • #4
McNanners said:
As I currently understand QM, everything exists as a non-tangible wave consisting of all possible outcomes until observation forces that wave to collapse into a single outcome, which becomes real.

Is that true so far?

Not really.

According to some interpretations of QM (such as the MWI), all of the possible outcomes are real; they all happen, just in different "worlds". According to other interpretations, "wave function collapse" is not a real process that happens to the quantum system, it's just a change in our knowledge about the system.

The general point is that QM in itself allows us to make predictions about the probabilities of various measurement results, but it does not tell us any underlying "mechanism" that produces those probabilities or results. Any talk about underlying mechanisms is interpretation, and there is no standard accepted interpretation of QM. So the best thing to do if you are not a QM expert is to refrain from making any interpretation at all, and just focus on how QM predicts the probabilities of various measurement results.
 
  • #5
McNanners said:
Without an observation, nothing forces the probability-wave to "decide" on a single outcome. Now what? I figure all possibilities within the wave drop to a probability of zero percent, ceasing the object's physical existence.
.Scott has already said above that observation in quantum mechanics (QM) is unrelated to life. Also, "observe" in QM does not (necessarily) mean "see" with our eyes. A better, more accurate, word is measurement and/or interaction.

(and please ignore my signature below, which is only a joke :smile:)
 
  • #6
DennisN said:
Also, "observe" in QM does not (necessarily) mean "see" with our eyes. A better, more accurate, word is measurement and/or interaction.
"Measurement" is too narrow, "interaction" is too broad. The best is - decoherence.
(BTW, good signature!)
 
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  • #7
McNanners said:
If it is, then what happens if something is never observed by anyone?

My guess is it would exist as a wave of all possible outcomes until an observation forces the wave's collapse into one physical outcome, just like everything else in QM. But in this case, the observation never takes place. Without an observation, nothing forces the probability-wave to "decide" on a single outcome. Now what? I figure all possibilities within the wave drop to a probability of zero percent, ceasing the object's physical existence. (my boldings)
Hi again, McNanners, I have already replied, but I reread your first post and wanted to highlight some things for you to think about:
  1. The Moon is a big, natural satellite of Earth, and it is fair to assume it obeys the laws of physics. It is known that the position of the Moon determines tides on Earth. So, if we assume that there is a short period of time when no living being observes the Moon, do you think the Moon would cease to exist, and the tides automagically would disappear?
  2. Furthermore, there is scientific evidence that the Moon is older than the earliest forms of life on Earth :wink:.
 
  • #8
DennisN said:
there is scientific evidence that the Moon is older than the earliest forms of life on Earth :wink:

but look, according to QM, the history before the very first observation act was a quasi-classical Everettian branch (or rather stem) which was a pure mathematical spatiotemporal object - albeit many billion mathematical years long, it's just one single primordial object, with the math-Big-Bang at its "beginning". So, the existence before observation is a mathematical mirage.
 
  • #9
AlexCaledin said:
but look, according to QM, the history before the very first observation act was a quasi-classical Everettian branch (or rather stem) which was a pure mathematical spatiotemporal object - albeit many billion mathematical years long, it's just one single primordial object, with the math-Big-Bang at its "beginning". So, the existence before observation is a mathematical mirage.
Talk of "existence before observation being a mathematical mirage" belongs in Copenhagen. Bohr had some very strange views about reality and Everett was quite unable to get him to understand MWI. Which is why he gave up on QM and went off to make bombs instead.

Everettian branching occurs through decoherence, not observation. It is a unitary evolution within the universal state.

By all means stick to Copenhagen and try to make sense of its anti-realism. Or stick to MWI and drop the metaphysics. But you can't mix and match.
 
  • #10
hilbert2 said:
In the conventional view of quantum mechanics, the "collapse" of quantum states has nothing to do with consciousness/intellingent observers. Analyzing a system that doesn't collapse at any point is actually simpler, as it's behavior is simply a solution of the time dependent Schroedinger equation.

It's more than simple. It's the only way that is consistent. It's easy enough to have both though. Do all the calculations without collapse and then apply the Born rule to see what you get. From then on it's a mixed state. It's only when people insist on using probabilities half way through an analysis that all hell breaks loose. You can do it as long as the information that is lost stays lost.
 
  • #11
McNanners said:
I'm relatively new to Quantum Mechanics (QM), so please correct me if I'm wrong at any point.

As I currently understand QM, everything exists as a non-tangible wave consisting of all possible outcomes until observation forces that wave to collapse into a single outcome, which becomes real.

Is that true so far? If it is, then what happens if something is never observed by anyone?

As others have mentioned... no, it's not "true" (it's not what QM says), but more importantly, "observe" in QM doesn't mean what you think it means. More to the point, something macroscopic (say, our very own Moon, but this would also apply to a speck of dust... or even to many things microscopic like large molecules) cannot _EVER_ be "never observed", because it's always strongly interacting with the rest of the Universe. Many of these interactions are "observations" in the context of QM, so such an object is constantly being "observed". Look up "environmentally induced decoherence" for more specific information, although this is highly technical (graduate level Physics).
 
  • #12
McNanners said:
what happens if something is never observed by anyone?
For us observers it doesn't really matter, since it will be unknown to us for ever.

Thus we can only speculate. It depends how the university is run.

From efficient design principles one would expect lazy generation. There observable items of the universe are generated on demand the moment someone observes it. This is the most parsimonious version since for far away objects only very little (a small stream of photons in the direction of the observer) needs to be generated. On the other hand, with the increase in the number of observers, and the increase in very short time resolution experiments, the generation on demand might exceed the capacity of the server running the universe, and then important and frequently observed items are kept in cache and are updated in the background.

On the other hand, some think that we live in a block universe, where (like in a movie) the complete history is already determined in all eternity, and observers just walk through it along their word lines. Others think that only the past is determined like in a block universe, and the future is generated at every moment. It is difficult to understand in such a view how this can happen for observers in very different Lorentz frames. But perhaps observers are restricted to the Earth, then this is not a problem.

In any case, it is undecidable on the basis of observations, by the nature of the question.
 
  • #13
Derek P said:
By all means stick to Copenhagen and try to make sense of its anti-realism. Or stick to MWI and drop the metaphysics. But you can't mix and match.
I think I perfectly can! Everett is looking from inside the unitary evolution+decoherence (every theorist is looking from inside his theory) and Bohr is looking from inside the whole Science (as any great scientific teacher ought to look) but they are describing the same thing.
 
  • #14
Derek P said:
Bohr had some very strange views about reality...

To my mind, Bohr had never strange views about “reality”. He was merely aware that “reality” cannot be described in terms of misleading classical concepts.
 
  • #16
McNanners said:
I'm relatively new to Quantum Mechanics (QM), so please correct me if I'm wrong at any point.
News flash -- any thread that starts with this will automatically be closed. o0)

Thread is done. Thanks folks.
 
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1. What is the significance of observing things in science?

Observation is a key aspect of the scientific method. It allows scientists to gather evidence and data about the world and form hypotheses and theories. Without observation, it would be difficult to make accurate predictions or understand the natural world.

2. Can things exist without being observed?

In quantum mechanics, there is a principle called the "observer effect" which suggests that the act of observation can affect the behavior of particles. However, just because something is not observed does not mean it does not exist. There are many things in the universe that exist even if they are not observed by humans.

3. What happens to things that are not observed?

It depends on the context. In quantum mechanics, some theories suggest that particles exist in a state of superposition until they are observed, at which point they collapse into a specific state. However, on a larger scale, things that are not observed may continue to exist and interact with their surroundings, even if we are not aware of them.

4. How do scientists study things that cannot be observed directly?

Scientists use various indirect methods to study things that cannot be observed directly. This can include using instruments such as telescopes and microscopes, conducting experiments, or analyzing data. They also use mathematical models and theories to make predictions and understand phenomena that cannot be directly observed.

5. Is it possible to observe everything in the universe?

No, it is not possible for humans to observe everything in the universe. The universe is vast and constantly expanding, and there are many things that are beyond our current technological capabilities to observe. However, scientists continue to make advancements in technology and techniques that allow us to observe more and more of the universe.

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