The Biggest Ideas in the Universe | 7. Quantum Mechanics

The Biggest Ideas in the Universe is a series of videos where I talk informally about some of the fundamental concepts that help us understand our natural world. Exceedingly casual, not overly polished, and meant for absolutely everybody.

This is Idea #7, "Quantum Mechanics." We talk about the quantum recipe -- the basic ingredients of wave function and Schrödinger equation, and how they are mixed together -- leaving deeper interpretational issues for later.

#science #physics #ideas #universe #learning #cosmology #philosophy #quantum

[squatchymcsquatchsquatch]

You literally have no idea how much I appreciate that you're putting this out during this period of time, and how much I enjoy being able to follow along with it. I love that you show how calculus is integral (pun intended) to all of these ideas and show a few examples, but that your focus is on the ideas themselves, not trying to explain 5d tensor homework problems to people like me who C'd my way through calc 106 the second time through... That's how you get people EXCITED about these big ideas. I am excited, because you sir, are doing an amazing job! Thank you.

[MartinWilson]

You can tell by the comments that Sean has reached a Feynman-level of teaching and inspiring. These videos will be referred to time and time again. We are watching history in the making. Despite them being lectures about 'we don't know', The honesty he provides us laymen trumps the deception laid on undergraduates. Devoting his career to turning this big ship around, in order to save future generations going wildly off-course. Cheers Sean.

[ArvinAsh]

Fantastic video that summarizes not only what QM is all about, but also how it came about. Brilliant! Should be required viewing for any student of quantum mechanics.

[jamesbra]

The only thing better than free physics lectures is physics lectures from the master, Sean Carroll, himself. Great day! Perhaps if this pandemic produces anything positive, it is a new Isaac Newton with all the answers lol.

[venil]

Who's disliking this? Must be Newton

[houstonsaft]

You are now one of my favorite humans for doing this.

[weissmann]

great kudos to you for using your time to put out these "classes" - super good presentations - clear and concise and at the right speed and depth

[thingsiplay]

12:24 "We have ultraviolet, which is even bluer than blue." - Sean Caroll, 2020

[ghoulunathics]

we are honored to have a man like you having his own youtube channel.

[SandipChitale]

Sean, can you please clarify definitively that even in Copenhagen interpretation whether or not the “observer” or “measurement device” in a quantum experiment, does or does not have to be a conscious entity like a human. As I understand it, “observer” is simply a macroscopic thing that interacts with a quantum system – which causes the “collapse” of the wave function according to Copenhagen interpretation. Did any one of Copenhagen club members ever say that “observer” has to be a conscious entity? I know that Jon Von Neumann and Wigner proposed that “observer” has to be a “conscious” entity. But later Wigner changed his mind. How many modern scientists use the word “observer” to mean “conscious” entity? Could you please convince your fellow scientists to clarify the word “observer” as it is used in quantum mechanics.

IMO the use of the English word – observer – for the measuring device in quantum experiments, was a unfortunate choice and has caused countless amount of mischief by new age gurus like Deepak Chopra. I am really annoyed by it.

I am surprised that even at respectable conferences like FQXi there is a discussion about “observer” in quantum mechanics as if it needs to be a conscious entity. Or is it still true many scientist think that “observer” has to be a conscious entity? It is obviously true that a macroscopic conscious entity can play a role of “observer” not because it is it is conscious but because it is macroscopic.

[jeffwells]

What a great video! You clarify so many things that I was fuzzy about all along and I only wish you were there when I was ploughing through this stuff 50 years ago!
You also touched on the difference between "observation" and "measurement, " something that I wish scientists had done from the beginning, because to the uninitiated an "observation" implies an "observer, " and that implies a conscious mind to a lot of people. This has led to travesties like Deepak Chopra telling people that "they create the universe" but simply looking at it, which is of course barking nonsense.
I wish science could change its terminology and change observation to measurement, but it's probably too late for that. In the same vein, the use of "theory" to label what is actually an "explanation" of a set of related facts has resulted in encouraging millions of ignorant religious types to insist that scientists are only guessing about these things.
I look forward to more of these videos!

[roblindsey-nassif]

It's a privilege to hear Sean Carroll. He's brilliant yet down-to-earth. What a thrill.

[antonio]

Out of laymen's curiosity I watched your Lecture #7, Quantum Mechanics (and propose to watch a few more of interest to me) and found it fascinating, even if a whole of the material went over my head. I wanted to tell you how very nice of you it is to devote your time and effort to make physics (some aspects of it) available to ordinary members of the public. Thank you very much for your generous offer of time and expertise.

[andybeans]

I'm not falling for that "You can watch cloud chambers..." trick again, I lost a whole day looking at tracks from all sorts of particles, totally mind-blown.

[grow-nannyinc]

I've been following you since your talks on quintessence and ive listened to 'The Big Picture' and 'Something Deeply Hidden' at least 50x each. Thanks for being my mentor all these years.

[YogiMcCaw]

As someone who can't do a lot of the math (but i could follow the simplified equations you drew), these lectures are clarifying a lot of concepts that I had only vague knowledge of. Of course, I still only have a beginner/novice knowledge of the these ideas, but nevertheless, this is helping me clarify how i think about these concepts that people bat around a lot when they talk about QM. Thanks, Sean!

[dmfrench]

You wouldn't know what I love about Dr. Carroll? He's not perfect, and he doesn't try to hide it. I always thought such a great mind would be superhuman, but not so! He gives me hope.

[zeynoleee]

It's extremely infuriating to come across videos like this, now that I graduated from high school. I can see how a waste of time my physics classes were compared to this. My teachers had either no real understanding of the topic or teaching in general. It's oftentimes forgotten how important it is to set the context before delving into subjects that are new and foreign to our understanding of the world we live in. And this is just a brilliant example of a high school level introduction of a subject!! thanks:)

[kayrosis]

That I could generally (though not perfectly) follow along with this just by listening, and not even watching is a testament to how well you're translating this into terms laymen can understand. This is a fantastic series you're doing Mr Carroll, I'm sure countless people will turn to these in the coming years.

[akumar]

Oh my God this is the hardest thing ever concept for the layman to understand, hopefully my limited understanding will be improved, Thank you Sir.