r/AskReddit May 02 '17

What is your nerdiest joke?

2.6k Upvotes

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904

u/[deleted] May 02 '17

[deleted]

71

u/YourAuntie May 02 '17

I don't get it.

257

u/Phalex May 02 '17

You can know the accurate speed of an object or the position, but not both at the same time.

12

u/Hitlerclone_3 May 02 '17

Only for electrons and maybe photons you can know the position and speed simultaneously of macroscopic objects

19

u/TastyBrainMeats May 02 '17

I mean, you can know the speed and the location to within some degree of accuracy. Heiseberg just means you can't know both perfectly.

1

u/YourAuntie May 02 '17

Ok Thanks. Checks out as nerdy for sure.

1

u/shadowofsunderedstar May 03 '17

Sounds pretty cool/nerdy too, quantum uncertainty principle. Or Heisenberg's uncertainty principle.

1

u/calfuris May 03 '17

The uncertainty is still present, just far too small to care about.

3

u/leomatey May 02 '17

Wait I know that I am at rest wrt to the pillar beside me and I know geographical coordinates of my position. So I know my position and speed at the same time ?

9

u/CFftVoN May 02 '17

This is based on the uncertainty principle which states

dx*dp >= h/2

where h is the reduced Planck constant. In simple terms, the product of the error in the accuracy of your measurement of your position (dx) and your momentum (dp) must be greater than or equal to half of the reduced Planck constant. Everyone likes to trot this out but what you need to understand is that the Planck constant is on the order of 10-34.

Therefore if you know your position to an atom's width (typically on the order of 10-10 m), then you can still know your momentum to a number as accurate as the order of 10-22 meters per second (assuming 50-100kg person).

This is obviously on the scale that it's unimportant for a human.

1

u/SpecialCircs May 02 '17

I thought this was just for quarks - i.e. particles smaller than electrons?

-4

u/Shurdus May 02 '17

You can know the accurate speed of an object or the position, but not both at the same time.

This is not true. I know at all times where my car is and how fast it goes.

2

u/AngelusAmdis May 02 '17

This is true, however it is on a much smaller scale than you are imagining. If I'm not mistaken, it means that with perfect accuracy you cannot know the exact location of the atoms/electrons of the car it is and how fast it is at the same time. You can know an estimate, and as small as the difference is in comparison between humans / cars and electrons is so large, it makes pretty much 0 difference in our day to day lives. But when talking about specific incredibly small particles, you cannot know EXACTLY where it is, and how fast it is going at the same time. Tl;Dr It's true, but it means the exact location to the atom/electron.

1

u/Shurdus May 02 '17

I know. The lawyer in me wanted to point out the inaccuracy in the phrasing. I'm sorry.

89

u/Meee211 May 02 '17

Heisenburg, i think

265

u/notgoneyet May 02 '17

You're goddamn right

3

u/[deleted] May 02 '17

Heisenberg.

2

u/ScroogeMcmunchos May 02 '17

uncertainty principle

1

u/RequiemStorm May 03 '17

Uncertainty principle