Uploaded May 2020 | Updated September 2026, 2 hours ago
We tend to think of Classical Physics as straightforward and intuitive and Quantum Mechanics as difficult and conceptually challenging. However, this is not always the case! In classical mechanics, a standard technique for finding the evolution equations for a system is the method of least action, where a functional known as the action is minimized to find the equations of motion. Inside of the action lives a mysterious function known as the Lagrangian. While mundane on the surface, it raises some serious questions on how to interpret classical mechanics.
To answer these questions, we must turn to quantum mechanics, and specifically the Feynman path integral formulation of quantum mechanics. This video shows how to get from the world of quantum mechanics to that of classical physics by a straightforward analogy to the ticking of stopwatches.
Feynman's QED Lectures:
youtube.com/watch?v=eLQ2atfqk2c&t=3620s
youtube.com/watch?v=kMSgE62S6oo
youtube.com/watch?v=jNNXD7fuE5E
youtube.com/watch?v=UigjOJm6F9o
Music Credits:
'Low Frequency Music'
Track Name: 'Good Day'
Music By: Low Frequency Music @ soundcloud.com/user-551516820
License for commercial use: Creative Commons Attribution 3.0 Unported "Share Alike" (CC BY-SA 3.0) License.
Music promoted by NCM goo.gl/fh3rEJ @
LoFi-HipHop.com
LAKEY INSPIRED
Track Names: "WARM NIGHTS"
Music By: LAKEY INSPIRED
Official SoundCloud soundcloud.com/lakeyinspired
Official YouTube Channel: youtube.com/channel/UCOmy8wuTpC95lefU5d1dt2Q
License for commercial use: Creative Commons Attribution 3.0 Unported "Share Alike" (CC BY-SA 3.0)
creativecommons.org/licenses/by-sa/3.0/legalcode
Music promoted by: Chill Out Records @ goo.gl/fh3rEJ
ChillOutMedia.com / LoFi-HipHop.com
'Homie Cat'
● Track Name: 'Sweet In Bitter,' 'Childhood Imagination'
● Official "Homie Cat" SoundCloud HERE - soundcloud.com/homie-cat
● Official "Homie Cat" Instagram HERE - instagram.com/homiecatbeats
● DOWNLOAD @ chilloutmedia.com/download
License for commercial use: Creative Commons Attribution 4.0 Unported "Share Alike" (CC BY-SA 4.0) License.
● Music promoted by NCM goo.gl/fh3rEJ @
LoFi-HipHop.com
"Who I Want To Be"
Track Name: "My Favorite Song Is Your Heartbeat"
• Snapchat - soundcloud.com/who-i-want-to-be
• SoundCloud - soundcloud.com/who-i-want-to-be
• Music released by: Chill Out Records goo.gl/fh3rEJ
License: Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
• See More @ LoFi-HipHop.com
We tend to think of Classical Physics as straightforward and intuitive and Quantum Mechanics as difficult and conceptually challenging. However, this is not always the case! In classical mechanics, a standard technique for finding the evolution equations for a system is the method of least action, where a functional known as the action is minimized to find the equations of motion. Inside of the action lives a mysterious function known as the Lagrangian. While mundane on the surface, it raises some serious questions on how to interpret classical mechanics.
To answer these questions, we must turn to quantum mechanics, and specifically the Feynman path integral formulation of quantum mechanics. This video shows how to get from the world of quantum mechanics to that of classical physics by a straightforward analogy to the ticking of stopwatches.
Feynman's QED Lectures:
youtube.com/watch?v=eLQ2atfqk2c&t=3620s
youtube.com/watch?v=kMSgE62S6oo
youtube.com/watch?v=jNNXD7fuE5E
youtube.com/watch?v=UigjOJm6F9o
Music Credits:
'Low Frequency Music'
Track Name: 'Good Day'
Music By: Low Frequency Music @ soundcloud.com/user-551516820
License for commercial use: Creative Commons Attribution 3.0 Unported "Share Alike" (CC BY-SA 3.0) License.
Music promoted by NCM goo.gl/fh3rEJ @
LoFi-HipHop.com
LAKEY INSPIRED
Track Names: "WARM NIGHTS"
Music By: LAKEY INSPIRED
Official SoundCloud soundcloud.com/lakeyinspired
Official YouTube Channel: youtube.com/channel/UCOmy8wuTpC95lefU5d1dt2Q
License for commercial use: Creative Commons Attribution 3.0 Unported "Share Alike" (CC BY-SA 3.0)
creativecommons.org/licenses/by-sa/3.0/legalcode
Music promoted by: Chill Out Records @ goo.gl/fh3rEJ
ChillOutMedia.com / LoFi-HipHop.com
'Homie Cat'
● Track Name: 'Sweet In Bitter,' 'Childhood Imagination'
● Official "Homie Cat" SoundCloud HERE - soundcloud.com/homie-cat
● Official "Homie Cat" Instagram HERE - instagram.com/homiecatbeats
● DOWNLOAD @ chilloutmedia.com/download
License for commercial use: Creative Commons Attribution 4.0 Unported "Share Alike" (CC BY-SA 4.0) License.
● Music promoted by NCM goo.gl/fh3rEJ @
LoFi-HipHop.com
"Who I Want To Be"
Track Name: "My Favorite Song Is Your Heartbeat"
• Snapchat - soundcloud.com/who-i-want-to-be
• SoundCloud - soundcloud.com/who-i-want-to-be
• Music released by: Chill Out Records goo.gl/fh3rEJ
License: Creative Commons Attribution-ShareAlike 4.0 International (CC BY-SA 4.0)
• See More @ LoFi-HipHop.com
