11 ай бұрын
Жыл бұрын
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@palfers1 3 күн бұрын
I could only take 10 minutes of this. It is moronic.
@alieslami2321 12 күн бұрын
Va l v Al c ucuci cu o h o o rdeh nu u u w hyyyyyyy
@alieslami2321 12 күн бұрын
Oh pinttt pp gg this ss re w v ooiew v sooio vcc c o nnj e cry T ti o n Ddd add d j o into ddd d as f e r d a g e r d ager EY E yey e Z e e e z ET e e e mannn Z e e e e go fd s g o d s gods
@alieslami2321 12 күн бұрын
Yeaj n mwe e t wvooo s o g maaa key o o unt o e r go d
@alieslami2321 12 күн бұрын
E r rr r r Y a d dd d d dddd w d dot
@alieslami2321 12 күн бұрын
Greetings e ned gen E d ccc r8sssss s sd re a l n uuum be r in e y e ye e e Z e e e e er e e ee xo ox g e n e d T a u r usssz a v iii rgoo o o w ooonedig o h o r e eeee Z e e e e e r e v Ed a ft e r t h T o h aasa d e d T e vo o r r r r hre r e thosss treee
@alieslami2321 12 күн бұрын
Nooo that Y e a h we e e an c hin h vggg online ree e e e e iam really l l o art so o n nnn er r r e eeta a Dof d I T D I T D O T US S DS DIG H RE N RE A D 0HO BU O HI TH A NK S SS D
@JAW-i8e 13 күн бұрын
I have found your lecture series to be first rate. Everything is so well explained particularly the topological aspects which were certainly neglected when I learned group theory as part of my graduate physics program back in the dark ages. Have you continued beyond the 40 lectures? If so how can they be accessed
@tursinbayoteev1841 14 күн бұрын
At 26:31 isn't it a directional derivative?
@apm77 16 күн бұрын
Suppose an expression like [T⊗U](V,W) was written in a notation that does not distinguish between A⊗B and (A,B), that is, in which the tensor product of A and B is indistinguishable from the ordered pair of vectors A and B, so for example [T⊗U](V,W) looks identical to [T⊗U][V⊗W]. Would any information actually be lost? In one sense, clearly yes, but that's because the null operator is overloaded: depending on the arguments we interpret the absence of an operator to mean either "acting upon" or "multiplied by", and we need to know which it is. But if that ambiguity were removed, would information still be lost? Because it seems like the distinction between an ordered pair of vectors and a rank 2 tensor is the same as the distinction between a stick and a lever, it's entirely a question of how it's being applied.
@hershyfishman2929 22 күн бұрын
39:59 even in dimension 1 clearly not all smooth differentiable atlases are compatible, as shown at 19.30 here: kzbin.info/www/bejne/fJKZhIV3rL5rZrs. See further 56.59 in that lecture.
@hershyfishman2929 Ай бұрын
32:19 in case it isn't clear, this means the set of all points on the graph
@alangrayson761 Ай бұрын
While your definition of a tangent space might be fine for a general manifold, it fails when the manifold is spacetime since we cannot have paths traversed in spacetime at speeds greater than c. If we omit these paths, it's not obvious how to construct a vector space on a tangent space. For example, we cannot simply multiply any vector on the tangent space by some arbitrary real scalar. I know you vehemently disagreed with this claim previously, but you're wrong.
@brendawilliams8062 Ай бұрын
49 :34 tracking differences. You rock. Thx
@rafisics Ай бұрын
16:50 Where can we find your book?
@brendawilliams8062 Ай бұрын
A comfortable, pertinent well explained representation. Appreciated. Thankyou
@darkknight3305 Ай бұрын
Thank you so much
@rifatkhondkar4327 Ай бұрын
This is an excellent lecture series. i have had a series of misconceptions that this series is clearing up and i'm honestly so thankful for these. Also can you please share names of some books that I can refer to while studying from this series?
@bobmvideos Ай бұрын
The Wikipedia article discussed at 21:46 seems to start here en.wikipedia.org/wiki/Comparison_of_vector_algebra_and_geometric_algebra#Equation_of_a_plane and not the main article on GA en.wikipedia.org/wiki/Geometric_algebra which appears briefly in the screen shots a few seconds later
@RandaRenneke Ай бұрын
Which lesson do I have to make it to in order to be irradiated again?
Ай бұрын
i' in video 3 and would like to see each new abstraction given a simple 2 or 3 or 4 diminsional example
@PymGordonArthur Ай бұрын
thanks :)
@faizahmed1601 2 ай бұрын
your teaching style is very awesome pleas provide me your lecture slides that would be very beneficial
@lucasgroves137 2 ай бұрын
Painful.
@AnthonyBrakus 2 ай бұрын
Bro, I appreciate your treatment of these subjects. I'm a self taught math/science enthusiast. Much of my knowledge has it's roots in your lessons. Thank you. Plus, I must add. When I have my balls I can make anything as well! The truth of mathematical abstraction strikes again ❤🎉😂
@XylyXylyX 2 ай бұрын
Thank you for your kind comment
@alexkatko431 2 ай бұрын
8 years later and still an amazing set of videos
@forheuristiclifeksh7836 2 ай бұрын
1:00
@danielvolinski8319 2 ай бұрын
In you zest to repeat everything at nauseum you never get to the point!
@XylyXylyX 2 ай бұрын
Acknowledged! Thank you for your patience.
@billfeatherstone3018 2 ай бұрын
Or mr Pauli’s😅
@billfeatherstone3018 2 ай бұрын
Thanks , its so nice to get the first principles.. like walking in Diracs footprints
@AnthonyBrakus 2 ай бұрын
If you were a University I think I would owe you $50,000 for these wonderful elucidations. Thanks for sharing this. You have given me a solid foundation for a deeper understanding of qm and gr.
@XylyXylyX 2 ай бұрын
Thank you for your kind comment and thanks for watching. I am going to restart my content creation soon!
@LolIGuess123 2 ай бұрын
Distracted by all the snot snorting and swallowing
@XylyXylyX 2 ай бұрын
Acknowledged. I am working on improving my production value these days. I am considering redoing all my old videos to get away from this. I probably need to write a script and control my speech or use an AI voiceover.
@AmrMuhammed137 3 ай бұрын
Would you please suggest a book for studying p-vectos and Covectors in a much more detailed manner ?
@nda4591 3 ай бұрын
Thanks for the great content! I‘ve been watching most of this channels playlists and I‘m mesmerised at the strong grip this lecturer has on the nitty gritty details of the topic. The mathematical depth is mind boggling! And the capacity to dig deep into the dirty details and resurface delivering on equal footing from the micro to the macroscale is fascinating! Thanks for the huge conscientious effort, many scientists are benefiting from your excellent communication skills and your rare intellectual skills(rarely seen such deep firm grip on mathematical physics). Looking forward for your next videos!
@felipeflores5403 3 ай бұрын
Hey, just wanted to say I was banging my head against the wall for a good 40 minutes trying to figure out why the angles added and not subtracted in eq 1.15. If I expand the exponential into hyperbolic functions and did it all by hand it worked out, but I was missing the intuition that I could exchange the exponential and an e_0 with a minus sign on the exponent because they anti-commute being on the same plane. Wonderful little detail. Thanks!
@XylyXylyX 3 ай бұрын
Yep. I still miss those little things. I am not sure GA will ever really take off because it requires learning a lot of specific facts and tricks, in my current opinion. Of course that is the way learning something new always feels. Still working on this myself.
@javadrazavi2840 3 ай бұрын
beautiful, clear and enjoyable representation of the subject
@PymGordonArthur 3 ай бұрын
Thanks. 🧡 from Serbia.
@VuongNguyen-mq7po 3 ай бұрын
It is such a good explanations of tensors that go to the fundamental level. Thank you for these wonderful courses.
@davidhand9721 3 ай бұрын
Hey buddy. You doing alright? Working on the next one? I'd like to see more on Dirac spinors at some point, get a better handle on how they relate to geometry of the field derivatives, if that's on the agenda. Totally unrelated to this series, I also really want to get a sense of what the SU(3) generators are doing in color space; the lie algebra series ends just before you get to that, I think. You're a really gifted science communicator, and I've got you to thank for a lot of things I know. I hope you understand that you're doing something really valuable here.
@XylyXylyX 3 ай бұрын
Thank you for your kind comments. I am really trying to put out more content. Perhaps this weekend? Tell me more about your specific interests regarding Dirac spinors?
@davidhand9721 3 ай бұрын
@@XylyXylyX I assume it's sort of like a tensor product space between a pauli spinor and something else. In the GA representation, pauli spinors are these rotors - bivectors + scalar. What's the second basis then? Given that it's about antimatter, and Feynman diagrams use matter going back in time to represent antimatter, _and_ the spinors context in the Dirac equation, I want to say that the second basis is something like a time derivative, differential form, something like that. I have no clue how that would be represented in GA even if I knew I was right, which I do not assume one bit. I think you once said that the Dirac gamma matrices had a geometric meaning, as well, and every time I try to work out what that is, I don't really trust my result very much. By analogy to the GA representation of the SU(2) group, i.e. the Pauli sigma matrices, I presume there's a direct correlation between the gamma STA basis and the gamma matrices. At least I expect the Lie bracket to be identical, but it's hard for me to picture how basis vectors are supposed to equate to what the gamma matrices are doing. These two things are related, so I'm pretty sure having the full set of Dirac spinor basis vectors will make it all click for me.
@XylyXylyX 3 ай бұрын
@@davidhand9721 ok. All those interests are easy to address. I’ll try to get to it asap.
@davidhand9721 3 ай бұрын
@@XylyXylyX thanks man! I appreciate it.
@evandrofilipe1526 3 ай бұрын
I just happened upon these videos and will probably watch all of the GA ones. I really like your slow methodical and skeptical approach to this topic, very unbiased and cool.
@jahanschad1445 3 ай бұрын
Excellent!
@jacquessmeets4427 4 ай бұрын
I stopped being a patreon because of low frequency of lessons. Did you stop? Any other plans for video's? As soon as you start, I will be your patreon again. Would be nice to have some reply. Thanks.
@XylyXylyX 4 ай бұрын
Thank u for your patronage. I will restart in a few weeks. I am very grateful for your viewership!
@sahhaf1234 3 ай бұрын
Same sentiments here...
@sahhaf1234 3 ай бұрын
@@XylyXylyX I hope that you do.. I have learned a lot from your lectures. I also hope that you will pick up the Lie groups series again. I am waiting for representation theory with excitement.
@jacquessmeets4427 3 ай бұрын
@@sahhaf1234 I also want to continue with representation theory. In the meantime, I started a course on representation theory on KZbin: see *Theoretical Physics with Mark Weitzman* - KZbin . He is following a book by Irene Verona Schensted (*A course on the application of Group theory on Quantum mechanics*, 1976). This is an introductory text. For me, the big advantage of this site is that you can use the “piazza” platform: a) the book is free available from this platform, including good notes/summaries on a series of books about this topic and b) you can ask questions and Mark responds quickly. Furthermore, this book (as I see it) has the same style as XylyXylyX. After Schensted he plans to discuss other books also. My experience thus far: The more I learn about representation theory, the more I like it (and the more I realize how important it is for physics). One advice: Study the subject from his book (self study) and use Piazza and use his KZbin videos' as supplementary only. You might give it a try.👍
@jacquessmeets4427 3 ай бұрын
@@sahhaf1234 I also want to continue with representation theory. In the meantime I have started a course on representation theory: see *Theoretical Physics with Mark Weitzman* site on KZbin. Link: (1) Theoretical Physics with Mark Weitzman - KZbin , Playlist "Group theory in Physics 2”. This channel has the extra (as I call it) “Piazza” features; that is that, after log-in, you can discuss items/questions with the instructor on the Piazza platform (in the same way as comments in KZbin videos). But the big advantage is that Mark always reacts and even very fast and detailed. This is very motivating (for me). Furthermore, for every course, you have access to many written documents: many notes/summaries of many books. The course *“Group theory in Physics 2”* (which basically discuss Representation theory) follows (to start with) the book *“A course on the Application of Group theory to Quantum Mechanics”* by Irene Verona Stensted, 1976. This is an introductory text on representation theory. In one way or another, I really like this book. It has in some sense the same style as XylyXylyX, but then written. So, “the best there is”. Furthermore, this book (as well as many other documents) can be downloaded for free from the Pizza platform. For me, the “Piazza” option, together with the good/fast communication is the deciding factor why I have chosen this channel. My advice: see the book as the “primary source” for self-study. The videos are only as supplementary (just as with XylyXylyX). Might give it a try 😀
@Channel-zb1fi 4 ай бұрын
Hey, what does your username mean?
@aaronTNGDS9 4 ай бұрын
Can't say enough about how helpful your videos are compared to a raft of others on this subject. At last I now see why such emphasis on matrices in the Lie Algebra/Group context exists without hand-waving and a perpetual shroud of mystery concealing what is happening behind the scenes. The raison d'etre if you will of the Lie Group topic and methodology so often taken for granted.
@XylyXylyX 4 ай бұрын
Thank you for your kind comment and for watching.
@davidhand9721 4 ай бұрын
What does it even mean physically to have a spinning reference frame? The guy taking all the measurements is spinning?
@XylyXylyX 4 ай бұрын
Yes, exactly.
@bahramhejrani9816 4 ай бұрын
Great!
@DominicProMax 4 ай бұрын
"A Mu B Nu - A Nu B Mu, e Mu e Nu, whew!!" 😂
@fjaresj 4 ай бұрын
Clap clap clap! Such an excellent explanation.
@drexflea52 4 ай бұрын
Sir, In comp notation u said covariant derivative adds an extra covariant index for any object's component it is differentiating. A vector component becomes (1, 1) object's component. But in CFREE u r saying covariant derivative of a vector field yields a vector and not an object of (1, 1) nature. I'm bit confused. Any words from u would be highly appreciated. Always been a follower of ur work. Your videos are something every undergrad and post grad mathematics students should go thru. That's what I feel. Thank u for putting out such quality content. From- India.
@miguelaphan58 5 ай бұрын
..clear and luminoues ..as no seen before..any place