Observation and Measurement

[metamagnet]

Here is something I have been thinking about while reading other threads on this board.

Can something observable be unmeasurable?
Conversely, can something unobservable be measured?

Curious as to others' input, Cheers!

[blueback]

I would say that for something to be observed it must be measurable. The only reason we can sense something is when it is a difference or a change between two or more values. Blind people can't see because they can't measure the difference between values like contrast and hue. Deaf people can't hear because they can't measure the difference between values like decibels and pitch. Etc.

For something to be observable but unmeasurable it would need to be a difference that we could sense but not one we could define. I can't think of an example of that off the top of my head.

For something to be unobservable but measurable I suppose all it would need to be is a difference that we can pick up on if it is scaled to an appropriate size for our senses, but not otherwise. For example, we can see stars with telescopes that are too faint to see unaided and we can see bacteria with microscopes.

[Allie]

Which specific threads led you to these questions?

Can something observable be unmeasurable?
The act of kindness.

Conversely, can something unobservable be measured?
One's thoughts/thought process, beliefs, faith. Measured by what they write/say, how they act/react or arrived at a decision.

I think someone with a strong science background can answer this question easily. For example, I am thinking of infinity, but I am not certain.

[zippikay]

Can something observable be unmeasurable?
The act of kindness.

I think someone with a strong science background can answer this question easily. For example, I am thinking of infinity, but I am not certain.

can't we measure act of kindness? we may not able to quantify exactly, but can't we say that we feel/perceive that this act is kind, but if he/she do this is even kinder...

talking about imaginary numbers such as infinity, can we say that by affixing an imaginary number to some quality or presumed quantity we are measuring it?
is infinity a measure?

[Allie]

but can't we say that we feel/perceive that this act is kind, but if he/she do this is even kinder...

I think this is judging rather than measuring.

I am equating my example of immeasurable with "priceless". Can we put a value on kindness? Can we have a consensus, or some agreement on the value of kindness? If not, then it's immeasurable.

immeasurable:
1. Impossible to measure. See Synonyms at incalculable.
2. Vast; limitless.


talking about imaginary numbers such as infinity, can we say that by affixing an imaginary number to some quality or presumed quantity we are measuring it?
is infinity a measure?

I can absolutely say that I don't know.

I am trying to keep my eyes from glazing over...That happens when it comes to science :p

[Stone]

talking about imaginary numbers such as infinity, can we say that by affixing an imaginary number to some quality or presumed quantity we are measuring it?
is infinity a measure?

Infinity is an abstraction and not a number. It expresses the possibility / ability for unlimited increasing or decreasing. If something can be described with a value / number, it is limited. And measurement works with values. Only things with beginning and end can be measured. Infinity is immeasurable.

[enWTFp]

Can something observable be unmeasurable?Yes, take Measure theory. Fractals, like Peano curves, that have measurable volume/area, but not measurable length. To view links or images in this forum your post count must be 2 or greater. You currently have 0 posts.

Simpler, take a line segment. It is finite in space and observable. But it is not measurable how many dots it contains, since the answer is infinity.Conversely, can something unobservable be measured?Yes, take Particle physics.

And simpler, take the sum of the geometric progression 1+1/2+1/4+...=2. You cannot observe the sum, but you measure it correctly.

[metamagnet]

Yes, take Measure theory. Fractals, like Peano curves, that have measurable volume/area, but not measurable length. To view links or images in this forum your post count must be 2 or greater. You currently have 0 posts.

Simpler, take a line segment. It is finite in space and observable. But it is not measurable how many dots it contains, since the answer is infinity.Yes, take Particle physics.

And simpler, take the sum of the geometric progression 1+1/2+1/4+...=2. You cannot observe the sum, but you measure it correctly.

Excellent examples, but I must ask if there are more....*physical* examples. Your line segment example is perfect, but line segments do not physically exist, they exist in our mind to help explain what we interact with in the world.
I realize i did not define "observable" or "measurable" but - while these explain the questions - are they're any "real world" examples, rather than constructs of the mind?





metamagnet added to this post, 5 minutes and 51 seconds later...

And for the record Peano Curves are a F*ckin awesome topic





metamagnet added to this post, 3 minutes and 48 seconds later...



For something to be observable but unmeasurable it would need to be a difference that we could sense but not one we could define. I can't think of an example of that off the top of my head.

Would the length of size of the universe be an example?


For something to be unobservable but measurable I suppose all it would need to be is a difference that we can pick up on if it is scaled to an appropriate size for our senses, but not otherwise. For example, we can see stars with telescopes that are too faint to see unaided and we can see bacteria with microscopes.
Good point, but are not microscopes and telescopes just extensions of our innate senses?

[Brutananadilewski]

Here is something I have been thinking about while reading other threads on this board.

Can something observable be unmeasurable?
Conversely, can something unobservable be measured?

Curious as to others' input, Cheers!

You bet, and it all stems from Heisenberg's Uncertainty Principle and quantum physics.

We can measure only 1 dimension of a particle. That is, we can either know a particle's momentum or position, but never both. Thus, we have an observable particle that is not entirely measurable, as there will be always be aspects of said particle that will remain unknown to us.

On the flip side, the implication of the uncertainty principle is that a particle exists in an infinte number positions until we seek to measure it; that is to say, our measurement brings the particle(or wave) into a single existence of any number of possible existences. Thus, the particle is in essence unobservable until someone actually looks for it, and in which case we can measure certain aspects of it (but not all, as you may recall). As an aside, this then brings up the can of worms known as the observer effect, in which any attempt to measure, or not measure, a particle, will invariably affect its dimensions (position or momentum) such that is it an impossiblity to view it without bias.

Cool stuff :)

[Tachyons]

Can something observable be unmeasurable?
Nothing observable can be absolutly measured. Only relatively measured, best guess so to speak. Even with that, we (humans) do pretty well.

Conversely, can something unobservable be measured?
Depends on which point of view your refering to. I can't observe your perseption, how could I measure it? However the thoughts in my head can be measured with my own personal yardstick...some would call it ethics.

[blueback]

You have to accept that measurements are always at least second hand. Even when we "directly" measure something, say by laying a ruler against it, we still have to wait for the light waves to bounce off of both objects, off of our retina, and then for the signal to be transmitted to our brain. That is a chain of at least three things that have changed.

I'm not sure that it would be even be fair to say that we "measure" our own emotions directly. Emotions always have a chemical component, and even if they didn't we can only measure a CHANGE in emotion, from one emotion to another or from one emotion to a different level of that emotion.

Therefore, since we have to accept that everything is measured indirectly, it doesn't make any sense to claim that a thing which is measured indirectly is not measured. We can't lay a rule against ethics but we can count the number of people it affects and how strongly it affects them. That is fundamentally no different from watching the leaves move to measure wind speed and direction.

Our senses are just tools that register change. Things like telescopes, surveys and thermometers are natural extensions of our senses in that they are things that register change.

[Ligda]

Something unobservable can only be indirectly measured with peoples subjective perceptions. Such as pain, happiness, fear, etc. and external aspects as well.

But something observable can't really be measured to the true ideal either. It is only as good as the measurement tool, and no tool is perfect. In practice, everything is an approximation. Going back to Plato.

[zibber]

What is measuring and how do you define it to be different from observation? Is any attachment/association of numerical values to anything a measurement? How do you decide the terms by which to measure something?

[alphawolf]

Can something observable be unmeasurable?

A smile.



Conversely, can something unobservable be measured?


Wind.

[metamagnet]

Wind.

Wind can be observed, we can feel it. I guess what I mean by "observation" is that which can be perceived, though not necessarily looked at [sight]. Or perceived with an extension of our senses (telescopes, etc).

[Vagrant]

Electrons, anybody?

You can either know where they are. Or you can know their charge. Not both.