Entanglement is one of the most important features — arguably, when you get down to it, the most important feature — of quantum mechanics, but it’s often glossed over in how we introduce the subject to students. Here we dive in, and I use this as an excuse to eventually talk about some of the different physical theories vying to be a complete formulation of quantum mechanics.
Update: I originally uploaded the wrong file, this should be the right one!
The Biggest Ideas in the Universe | 8. Entanglement
And here is the associated Q&A video. (Sorry I was in a hurry and didn’t do the lighting correctly … I’ll never make it big in Hollywood at this rate.)
The Biggest Ideas in the Universe | Q&A 8 - Entanglement
Worried I posed my previous question badly! Second attempt: why can’t the observation of a particle’s spin affect how it was entangled if the arrow of time is emergent?
Dr. Carroll, as always, thanks for all you are doing!
In the double slit experiment, when a single photon/electron progresses from its source, through the double slit, to the screen, is it correct that “many worlds” requires that there be a world for every possible location that the photon/electron could strike? Would it be too much to show and briefly step through a wave equation that would apply for this particular situation. Thank you
Many thanks for these very inspiring videos. I have a very basic question about (your videos about) Quantum Mechanics: the wave function is often said to depend on x and t (i.e. space and time).
Is it correct that quantum mechanics (in the form of Schrodinger equation) assumes the existence of an “absolute time”? If this is the case, isn’t there some tension with (even special) relativity ?
Hello Prof. Carroll,
I still am not clear of the explanation on “Bertlmann’s Socks”.
Alice observers spin in Z-axis to be UP.
Then Bob observes spin in X-axis to be RIGHT.
1. Will Alice spin change if measured again in Z-axis? (Are they still entangled?)
2. If not, then why can’t I say that Alice and Bob have UP spin on X and RIGHT spin on Z? (which may later change if measured again because they are now un-entangled and obeys spin uncertainty)
Please let me know if my question is relevant.