Editing 1473: Location Sharing

{{comic
| number    = 1473
| date      = January 14, 2015
| title     = Location Sharing
| image     = location_sharing.png
| titletext = Our phones must have great angular momentum sensors because the compasses really suck.
}}

==Explanation==
{{incomplete|First draft.}}
In this comic, [[Megan]] is visiting a website on her mobile phone. After loading it, the website {{w|Location-based service|asks for her location}}. The choice between allowing or denying a website or app access to certain information is common among smartphones. The term "location sharing" specifically refers to when a smartphone user shares their location with such an entity. An example is a weather app which would need your location in order to automatically find the correct forecast.

Megan is then asked her {{w|momentum}}, which she denies. The joke is based on the Heisenberg {{w|uncertainty principle}}, which, in quantum mechanics, states that some pairs of values cannot be known precisely and simultaneously. The most famous example of such values (and the example Heisenberg himself used) are location and momentum: the more precisely you measure the location of a particle, the less certain you are of its momentum, and vice versa.

Heisenberg's uncertainty principle is typically observed only at sub-atomic scales, and not at macroscopic scales (it is possible to measure both the position and momentum of a large object such as a smartphone or human being). Nonetheless, Megan refuses, actively enforcing the uncertainty principle as a conscious action rather than as a simple limitation of knowledge.

The title text refers to the inclusion of {{w|gyroscope}}s in modern cell phones that measure angular momentum, mostly to detect when the phone is tilted, but also used in a few mobile games. Randall suggests the poor accuracy of the compasses in mobile phones (measuring the angular position) is due to the gyroscopes being too good. If both the gyroscope and the compasses were completely accurate to a subatomic scale, it would violate the uncertainty principle. Modern phones also include varied technologies (such as GPS) to pinpoint the user's location, with varying degrees of accuracy.

The uncertainty principle has previously been referenced in [[824: Guest Week: Bill Amend (FoxTrot)]]. It has also been discussed in relation to the two comics [[1404: Quantum Vacuum Virtual Plasma]] and [[1416: Pixels]].

==Transcript==
:[Megan is holding her phone. Above her is the text she can see on the screen:]
:This website wants to know your location.
:[Two buttons are below this text. The first is white with a black frame and black text. The second (the chosen button) also has a black frame, but inside the frame is a black rectangle with white text. Around the chosen button are small lines indication rays.]
:Deny
:'''Allow'''

:[Megan is holding her phone.]

:[Megan is holding her phone. Above her is again the text she can see on the screen.]
:This website wants to know your momentum.
:[Two buttons are below this text. The first (the chosen button) has a black frame, but inside the frame is a black rectangle with white text. The second is white with a black frame and black text. Around the chosen button are small lines indication rays.]
:'''Deny'''
:Allow

:Megan: Nice try.

{{comic discussion}}
[[Category:Comics featuring Megan]]
[[Category:Physics]]
[[Category:Smartphones]]