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Zeroing in on Zero-Point Motion Inside a Crystal

physics.aps.org

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Re: Zeroing in on Zero-Point Motion Inside a Crystal

#11

Post by jagged-chisel »

irjustin wrote: post #8
jagged-chisel wrote: post #4

Earlier quoted context omitted.

No it does not dictate such. And you’re describing “the observer effect.” Heisenberg says the more accurately you measure one property, the less accurately you can measure a second [related] property. The usual property pair used in explaining the principle are position and momentum.

> Heisenberg says the more accurately you measure one property, the less accurately you can measure a second [related] property. mmm you've redescribed what the parent post was saying. Heisenberg's principal is about the _knowability_ and not the measurement. So it's fundamental regardless of whether you measure it or not. This is why it's impossible to cool something to absolute zero. Because fundamentally, it's pos…

There is no cause and effect in Heisenberg, nor due to it.

Re: Zeroing in on Zero-Point Motion Inside a Crystal

#12

Post by Khaine »

irjustin wrote: post #8
jagged-chisel wrote: post #4

Earlier quoted context omitted.

No it does not dictate such. And you’re describing “the observer effect.” Heisenberg says the more accurately you measure one property, the less accurately you can measure a second [related] property. The usual property pair used in explaining the principle are position and momentum.

> Heisenberg says the more accurately you measure one property, the less accurately you can measure a second [related] property. mmm you've redescribed what the parent post was saying. Heisenberg's principal is about the _knowability_ and not the measurement. So it's fundamental regardless of whether you measure it or not. This is why it's impossible to cool something to absolute zero. Because fundamentally, it's pos…

Doesn't measurement == knowability ?

like you don't truly know something until you measure it?

Re: Zeroing in on Zero-Point Motion Inside a Crystal

#13

Post by irjustin »

Khaine wrote: post #12
irjustin wrote: post #8

Earlier quoted context omitted.

> Heisenberg says the more accurately you measure one property, the less accurately you can measure a second [related] property. mmm you've redescribed what the parent post was saying. Heisenberg's principal is about the _knowability_ and not the measurement. So it's fundamental regardless of whether you measure it or not. This is why it's impossible to cool something to absolute zero. Because fundamentally, it's pos…

Doesn't measurement == knowability ? like you don't truly know something until you measure it?

Knowability directly means "ability to know" meaning whether you are even able to know it at all i.e. you can/can't ever know it.

The Heisenberg uncertainty means you can't know it (i.e. it's not a value/property exists to extract), regardless if you try to measure it.

Re: Zeroing in on Zero-Point Motion Inside a Crystal

#14

Post by Khaine »

irjustin wrote: post #13
Khaine wrote: post #12

Earlier quoted context omitted.

Doesn't measurement == knowability ? like you don't truly know something until you measure it?

Knowability directly means "ability to know" meaning whether you are even able to know it at all i.e. you can/can't ever know it. The Heisenberg uncertainty means you can't know it (i.e. it's not a value/property exists to extract), regardless if you try to measure it.

I took knowability to be, how well you know the properties of a particle? For example, if you could perfectly knew the position of a particle, then you would have no knowledge of its momentum.

I thought Hisenberg meant the more you knew about one property (i.e. the smaller the bound on the position of a particle) the less you knew about the other property.

I'm not an expert on this, so more than happy to be corrected.

Re: Zeroing in on Zero-Point Motion Inside a Crystal

#15

Post by jagged-chisel »

Khaine wrote: post #14
irjustin wrote: post #13

Earlier quoted context omitted.

Knowability directly means "ability to know" meaning whether you are even able to know it at all i.e. you can/can't ever know it. The Heisenberg uncertainty means you can't know it (i.e. it's not a value/property exists to extract), regardless if you try to measure it.

I took knowability to be, how well you know the properties of a particle? For example, if you could perfectly knew the position of a particle, then you would have no knowledge of its momentum. I thought Hisenberg meant the more you knew about one property (i.e. the smaller the bound on the position of a particle) the less you knew about the other property. I'm not an expert on this, so more than happy to be corrected…

irjustin is either redefining words to suit their purpose, or isn’t articulating their point well.

To even “know” position, one must measure it. Because electrons are always in motion, if you want to know their speed perfectly, you won’t know their position precisely. You’ll have a probability of where the electron should be, but no definite position.

That’s all Heisenberg has to say. It doesn’t talk about your observations changing the thing you observed, it doesn’t “cause” anything to happen, it is not dependent on the consciousness of the observer and doesn’t make effects itself.

Re: Zeroing in on Zero-Point Motion Inside a Crystal

#16

Post by jagged-chisel »

irjustin wrote: post #8
jagged-chisel wrote: post #4

Earlier quoted context omitted.

No it does not dictate such. And you’re describing “the observer effect.” Heisenberg says the more accurately you measure one property, the less accurately you can measure a second [related] property. The usual property pair used in explaining the principle are position and momentum.

> Heisenberg says the more accurately you measure one property, the less accurately you can measure a second [related] property. mmm you've redescribed what the parent post was saying. Heisenberg's principal is about the _knowability_ and not the measurement. So it's fundamental regardless of whether you measure it or not. This is why it's impossible to cool something to absolute zero. Because fundamentally, it's pos…

I didn’t. As I said, taneq mentions the observer effect. This is not the same as the Heisenberg Uncertainty Principle.

Re: Zeroing in on Zero-Point Motion Inside a Crystal

#17

Post by irjustin »

jagged-chisel wrote: post #15
Khaine wrote: post #14

Earlier quoted context omitted.

I took knowability to be, how well you know the properties of a particle? For example, if you could perfectly knew the position of a particle, then you would have no knowledge of its momentum. I thought Hisenberg meant the more you knew about one property (i.e. the smaller the bound on the position of a particle) the less you knew about the other property. I'm not an expert on this, so more than happy to be corrected…

irjustin is either redefining words to suit their purpose, or isn’t articulating their point well. To even “know” position, one must measure it. Because electrons are always in motion, if you want to know their speed perfectly, you won’t know their position precisely. You’ll have a probability of where the electron should be, but no definite position. That’s all Heisenberg has to say. It doesn’t talk about your obser…

> irjustin is either redefining words to suit their purpose, or isn’t articulating their point well.

https://www.merriam-webster.com/dictionary/knowability

Man you're frustrating. I'm literally using the definition. Just because you don't know what it means...

Re: Zeroing in on Zero-Point Motion Inside a Crystal

#18

Post by irjustin »

Khaine wrote: post #14
irjustin wrote: post #13

Earlier quoted context omitted.

Knowability directly means "ability to know" meaning whether you are even able to know it at all i.e. you can/can't ever know it. The Heisenberg uncertainty means you can't know it (i.e. it's not a value/property exists to extract), regardless if you try to measure it.

I took knowability to be, how well you know the properties of a particle? For example, if you could perfectly knew the position of a particle, then you would have no knowledge of its momentum. I thought Hisenberg meant the more you knew about one property (i.e. the smaller the bound on the position of a particle) the less you knew about the other property. I'm not an expert on this, so more than happy to be corrected…

> I took knowability to be, how well you know the properties of a particle?

No, I'm using the literal definition: https://www.merriam-webster.com/dictionary/knowability

> I thought Hisenberg meant the more you knew about one property (i.e. the smaller the bound on the position of a particle) the less you knew about the other property.

Yes, this is it, but remove "you knew"... just - property. The more one property is defined, the less the other property is.

The key I'm trying to get across is it doesn't matter what you, the observer know/don't know (i.e. measure). As temp ->abs_zero, momentum becomes more-undefined/fuzzier. Nothing to do with you measuring.

The "other" property is fundamentally undefined (i.e. not knowable, i.e. able to be known).

Maybe we're getting hung up on our shared understanding of "knowable" and I shouldn't have used it, but it is, technically, the correct usage.

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