# the Indeterminacy principle **URL:** \ **Category:** Factual Questions\ **Created:** [July 29, 2017, 3:40pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392 "2017-07-29T15:40:38Z")\ **Posts on this page:** 13\ **Page:** 2
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [July 30, 2017, 12:33pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/21 "2017-07-30T12:33:08Z")
A baseball truly at rest would have less momentum (i.e., zero) than a moving electron. But a baseball could have many, many times the momentum of an electron and still be moving so slowly as to be indistinguishable from “at rest”. ---
**Author:** ![abashed](https://avatars.discourse-cdn.com/v4/letter/a/c6cbf5/32.png) [@abashed](https://boards.straightdope.com/u/abashed)\ **Post date:** [July 30, 2017, 1:54pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/22 "2017-07-30T13:54:09Z")
> [@ftg](#): > > The opposite. The faster it goes (or the heavier it is), the [shorter](https://en.wikipedia.org/wiki/Matter_wave) the wavelength. > > The problem with an object at complete and total rest is that its wavelength is infinite\*. Which is not possible. Hence everything is always jiggling around in a certain sense. The bigger the object, the less the “jiggle”. As noted, a baseball is so immense in terms of quantum effects it’s impossible to realistically measure such motion. > > - Which means its position could be nailed down to “Somewhere in the Universe.” Oh, now even\* I\* can understand that! 😃 When you said ‘the faster it goes (or the heavier it is)…’ were you talking about the relativistic effects? Also, is this why we get such odd behaviour of free particles in a vacuum in the double-slit-experiment, i.e., that they are isolated from anything much bigger? ---
**Author:** ![abashed](https://avatars.discourse-cdn.com/v4/letter/a/c6cbf5/32.png) [@abashed](https://boards.straightdope.com/u/abashed)\ **Post date:** [July 30, 2017, 1:56pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/23 "2017-07-30T13:56:34Z")
> [@Chronos](#): > > A baseball truly at rest would have less momentum (i.e., zero) than a moving electron. But a baseball could have many, many times the momentum of an electron and still be moving so slowly as to be indistinguishable from “at rest”. Okay, that makes sense from what ftg said. 🙂 ---
**Author:** ![Trinopus](https://avatars.discourse-cdn.com/v4/letter/t/2bfe46/32.png) [@Trinopus](https://boards.straightdope.com/u/Trinopus)\ **Post date:** [July 30, 2017, 4:38pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/24 "2017-07-30T16:38:34Z")
> [@ftg](#): > > . . . The problem with an object at complete and total rest is that its wavelength is infinite\*. Which is not possible. Hence everything is always jiggling around in a certain sense. . . . I have read science articles that say this is why liquid helium doesn’t freeze solid. The “quantum jiggle” is just enough to keep it liquid. (Is this correct, or am I remembering it completely wrong?) ---
**Author:** ![eschereal](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eschereal/32/18939_2.png) [@eschereal](https://boards.straightdope.com/u/eschereal)\ **Post date:** [July 30, 2017, 4:40pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/25 "2017-07-30T16:40:18Z")
Can a baseball be at relative net-rest? Where its net momentum within its frame of reference is zero but the motion of its many constituent parts is each non-zero? ---
**Author:** ![Half\_Man\_Half\_Wit](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/half_man_half_wit/32/21766_2.png) [@Half\_Man\_Half\_Wit](https://boards.straightdope.com/u/Half_Man_Half_Wit)\ **Post date:** [July 30, 2017, 6:07pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/26 "2017-07-30T18:07:26Z")
> [@Derleth](#): > > [I have a post which goes into this in detail, so instead of rewriting all of it I’ll just link to it.](http://boards.straightdope.com/sdmb/showpost.php?p=17495230&postcount=27) Good post, but I’d like to urge some caution against overstating the analogy between duration and frequency of a wave, and the uncertainty principle (not that I think you do, but people might get the wrong impression). Basically, there’s nothing counterintuitive about the relationship between frequency and duration: a note that’s been played for a certain finite time simply doesn’t have a single frequency; and when we record that note, we have exact values for its duration and the frequency range it spans. All of its properties are thereby completely known and fixed. The same can’t be said for a quantum particle: if it is, say, in a fairly sharp state of momentum, then it’s not possible to exactly predict its position; but upon measurement, we will always find it in a single place. So all of the particle’s properties, as they are revealed to us via measurement, are not fixed by what we know about its state. Furthermore, uncertainty also exists between discrete variables: for, e.g., a particle’s spin, which can be either ‘up’ or ‘down’ in a given direction, there exists an uncertainty principle between different orthogonal directions of spin—perfectly knowing spin in the x-direction means you don’t know anything about spin in y-direction. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [July 30, 2017, 8:54pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/27 "2017-07-30T20:54:07Z")
> [@](#): > > Quoth **eschereal** : > > Can a baseball be at relative net-rest? Where its net momentum within its frame of reference is zero but the motion of its many constituent parts is each non-zero? Yes, by definition. “Its own frame” means the frame where its overall momentum is zero. But we can’t tell what frame that is. (surprisingly, the math for combining quantum mechanics and special relativity still manages to all turn out just fine) > [@](#): > > Quoth **Half Man Half Wit** : > > The same can’t be said for a quantum particle: if it is, say, in a fairly sharp state of momentum, then it’s not possible to exactly predict its position; but upon measurement, we will always find it in a single place. And immediately upon making that position measurement, it’s no longer in a fairly sharp momentum state. ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [July 31, 2017, 10:30am UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/28 "2017-07-31T10:30:36Z")
OP has his answer, I think, so jokes are in order: > [@](#): > > Erwin Schrödinger and Werner Heisenberg are driving down the road with the top down, having the time of their lives. They blow past a hidden state patrol officer who jumps in his car and pulls them over a few miles down the road. The officer gets out of his car, hitches up his britches, and saunters up to Heisenberg who is driving. > > He motions to roll the window down and Werner complies, then the officer asks: “Sir, do you have any idea how fast you were going?” To which Heisenberg replies: “No Sir. But I know exactly where I am.” The cop, taken aback by the non-sequitur, begins to believe that he has stumbled into a drug bust so asks to search the car. Werner consents, and pops the trunk. The cop walks back, takes a look, then suddenly pops up with a disgusted look on his face, asking: “Did you know there is a dead cat in here?” And Schrödinger says “Well we do now!” > > The cop can’t seem to find anything to charge the men with, walks back to the driver and begins writing a ticket. He says, as he has done many times before: “Sir, I clocked you going exactly 88 miles per hour!” And Heisenberg exclaims: “Great. Now I’m completely lost!” ---
**Author:** ![abashed](https://avatars.discourse-cdn.com/v4/letter/a/c6cbf5/32.png) [@abashed](https://boards.straightdope.com/u/abashed)\ **Post date:** [July 31, 2017, 11:10am UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/29 "2017-07-31T11:10:20Z")
> [@septimus](#): > > OP has his answer, I think, so jokes are in order: Very good. 😉 As a post script I think I would like to say that I have learnt that sub-atomic particles are very \* elusive.\* ---
**Author:** ![swampspruce](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/swampspruce/32/261_2.png) [@swampspruce](https://boards.straightdope.com/u/swampspruce)\ **Post date:** [July 31, 2017, 3:00pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/30 "2017-07-31T15:00:15Z")
**abashed** , thank you for asking this as I am in the process of reading (for fun),“[Quantum Mechanics: The Theoretical Minimum](https://www.amazon.ca/Quantum-Mechanics-Theoretical-Leonard-Susskind/dp/0465062903)” and this clears a few things up for me. **Derleth** , thank You for the clear analogy! ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [July 31, 2017, 3:30pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/31 "2017-07-31T15:30:45Z")
I think we did a set of Heisenberg jokes a couple of months ago. This is the one I like. Heisenberg is driving down the road and he gets pulled over by a cop. The cop walks up to him and says “Do you know how fast you were going?” Heisenberg says “No, but I know **exactly** where I am!” ---
**Author:** ![Nature\_s\_Call](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nature_s_call/32/19006_2.png) [@Nature\_s\_Call](https://boards.straightdope.com/u/Nature_s_Call)\ **Post date:** [July 31, 2017, 6:29pm UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/32 "2017-07-31T18:29:53Z")
> [@Derleth](#): > > [I have a post which goes into this in detail, so instead of rewriting all of it I’ll just link to it.](http://boards.straightdope.com/sdmb/showpost.php?p=17495230&postcount=27) This is awesome. It caused me to google, where I found this [Interactive Guide to the Fourier Transform](https://betterexplained.com/articles/an-interactive-guide-to-the-fourier-transform/). This really helped me understand what you explained even more intuitively. ---
**Author:** ![abashed](https://avatars.discourse-cdn.com/v4/letter/a/c6cbf5/32.png) [@abashed](https://boards.straightdope.com/u/abashed)\ **Post date:** [August 1, 2017, 6:04am UTC](https://boards.straightdope.com/t/the-indeterminacy-principle/792392/33 "2017-08-01T06:04:53Z")
> [@swampspruce](#): > > **abashed** , thank you for asking this as I am in the process of reading (for fun),“[Quantum Mechanics: The Theoretical Minimum](https://www.amazon.ca/Quantum-Mechanics-Theoretical-Leonard-Susskind/dp/0465062903)” and this clears a few things up for me. > **Derleth** , thank You for the clear analogy! Glad to be of service swampspruce ;). [Previous page](https://boards.straightdope.com/t/the-indeterminacy-principle/792392.md?page=1)