Observing observables of an entity

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Discussion Overview

The discussion revolves around the observation of different observables of entities, particularly in the context of quantum mechanics. Participants explore how observables, such as the position of an electron, are measured and whether these processes fundamentally involve interactions with light waves. The conversation touches on definitions of particles and quantum states, as well as the philosophical implications of measurement in quantum mechanics.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • Some participants question how different observables of an entity, like an electron, are observed and whether all observation processes involve interactions with light waves.
  • There is a discussion about the definition of an "entity," with some suggesting it refers to a quantum state while others seek clarification on the terms used.
  • One participant proposes that observables do not have significance before measurement, likening the concept to asking about election results before an election.
  • Another participant emphasizes that the wavefunction, which solves the Schrödinger equation, has significance and provides probabilities for measurement outcomes.
  • Some participants argue that observables are properties of observation rather than properties of the entity itself.
  • There is mention of indirect measurements in quantum physics, where properties of particles are inferred rather than directly observed.
  • Concerns are raised about the validity of personal interpretations of quantum mechanics without a solid understanding of the theory.

Areas of Agreement / Disagreement

Participants express multiple competing views regarding the nature of observables and the process of measurement in quantum mechanics. There is no consensus on the definitions of key terms or the implications of measurement.

Contextual Notes

Participants highlight the complexity of defining "observation" and "observable" independently, indicating that these concepts are intertwined. There are also references to various interpretations of quantum mechanics, suggesting a lack of agreement on foundational principles.

quantum philosopher
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TL;DR
Observing observables of an entity
●How are different observables of an entity ( like electron ) observed ?
● Is every observation process fundamentally interaction of the entity with light waves?
● how does observation takes place?
 
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What research have you done on this so far? What have you found?
 
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quantum philosopher said:
TL;DR Summary: Observing observables of an entity

●How are different observables of an entity ( like electron ) observed ?
● Is every observation process fundamentally interaction of the entity with light waves?
● how does observation takes place?
What even is an entity? From your question it seems that you mean a quantum state. Is that the case? Or does it refer specifically to particles?
 
How do you define a particle and a quantum state? Only after knowing that I can say what I mean according to you.
 
quantum philosopher said:
How do you define a particle and a quantum state? Only after knowing that I can say what I mean according to you.
Maybe you should start by that? I mean observables act on quantum states.

A quantum state can be written as ##|\Psi\rangle## or in position space as a wavefunction ##\Psi(\mathbf r)##, is a vector of Hilbert space, it encodes all of the state of the system.

(Fundamental ) Particles are a series of different models with specific properties (usually single particles can be very localized in space when measured). A quantum state may contain a single particle, ##N>1## particles or none at all. Some of the properties of a quantum state depend on the type of particles that you are trying to describe.
 
phinds said:
What research have you done on this so far? What have you found?
Nowhere I found any text regarding how do observation takes place so my research is done in my copy using my own thinking . And in quantum mechanics different interpretations are there . So I have also developed my own interpretation . According to my research (may be wrong) which is philosophical , observables have no significance before measurement . First i will discuss about significance of observables then how they are done . When we measure suppose position of an electron we get one space coordinate as it's position . So asking about "position of an electron or a proton before measuring it " is like asking about election results before election . Thus "position of an object " is not a valid phrase but " value obtained after position measurement " is a valid one . Till here no quantum viewpoint I have used . Now Schrödinger equation says that there is a thing which we can know about an object without observation process . That is its wavefunction (which is just a function dependent on space and time and solves Schrödinger eqn). Thus "Wave function of an object" is a valid phrase and wave function have a significance . Mod square of the wavefunction at a particular space coordinate gives us the probability of getting it as the value of position(no other observable but position) when measured . The conclusion is that observables are not properties of an entity but wave function and what we get after operators acting on it are properties of it but observables are properties of observation . Till here I have complete faith on my viewpoint except one big issue that is i cannot define "what is observation" and "what is observable" Independently . I would only be able to say observing means obtaining observables of an entity and observables are what we get after observation. So I thaught it appropriate to introduce a separate kind of entity which would be responsible to carry out interaction between other entities(which is photon).
 
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pines-demon said:
Maybe you should start by that? I mean observables act on quantum states.

A quantum state can be written as ##|\Psi\rangle## or in position space as a wavefunction ##\Psi(\mathbf r)##, is a vector of Hilbert space, it encodes all of the state of the system.

(Fundamental ) Particles are a series of different models with specific properties (usually single particles can be very localized in space when measured). A quantum state may contain a single particle, ##N>1## particles or none at all. Some of the properties of a quantum state depend on the type of particles that you are trying to
By entities I mean something that we know it exists . I can never say it is localized in space . I can say that when I measure it's location I get one and only one value.
 
Last edited:
quantum philosopher said:
TL;DR Summary: Observing observables of an entity

●How are different observables of an entity ( like electron ) observed ?
● Is every observation process fundamentally interaction of the entity with light waves?
● how does observation takes place?
A better word is measurement. The simplest definition of a measurement is any experiment or process that results in gaining information about a system or particle. Typical measurements involve a particle interacting with a detector or screen. Or, a measurement of the wavelength of light emitted from a system. In general, there are a wide range of measurements corresponding to all the different types of experiment you can do.

Because it's difficult or impossible to measure an elementary system directly, measurements are often indirect. The transition of an atom between eneregy levels is inferred from the wavelength of light in its emission or absorption spectrum. You can't directly look at an electron and watch it jump from one state to another.

If you dig more deeply, then measurement in quantum physics becomes quite a subtle concept.
 
quantum philosopher said:
I have also developed my own interpretation . According to my research
Personal theories must be published in the professional scientific literature before they can be discussed here.
 
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quantum philosopher said:
I have also developed my own interpretation .
As an additional note for future reference, someone who says this...

quantum philosopher said:
How do you define a particle and a quantum state?
...is in no position to even try to interpret QM. You can't interpret a theory if you don't even know what the theory says or how it makes predictions.
 
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