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Lessons by 3blue1brown

3blue1brown.com

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Re: Lessons by 3blue1brown

#71

Post by xpe »

ylhert wrote: post #41

3blue1brown gives me hope that there are a few Michael Jordan level teachers out there, and youtube/the internet will allow us to find those people and reward them appropriately

> 3blue1brown gives me hope that there are a few Michael Jordan level teachers out there…

The basketball player (Michael Jeffrey Jordan) or machine learning professor (Michael Irwin Jordan at Cal Berkeley)?

If the former, surely we have better role models for teaching than a basketball player. Apologies for the prodding, but cross-domain idolatry gets me riled up.

For me and thousands of others, Grant Sanderson, creator of 3b1b, is the archetype of an internet-era world class educator. Thanks Grant.

> … and youtube/the internet will allow us to find those people and reward them appropriately

Yes, there are many others across various fields. While profits can be a useful motivator, we don’t want that to be the only mechanism. Education isn’t only about the most profitable topics or the students already best situated to learn.

Re: Lessons by 3blue1brown

#72

Post by Sohcahtoa82 »

eimrine wrote: post #33
pdpi wrote: post #19

Earlier quoted context omitted.

My "ten minutes to understand something I never quite got" moment was his video on Fourier Transforms.

Just listen to some music with spectrum visualization, this is a Fourier transform of what you are listening right now.

That only tells you what the result of a Fourier transform is. It doesn't tell you how it works.

Re: Lessons by 3blue1brown

#73

Post by jmartrican »

haberman wrote: post #38

I would love it if some of these educational YouTube videos came with exercises. I watch a lot of educational YouTube videos. But I've come to see them as more entertainment than education. Not in terms of the quality of the videos (which is often excellent), but in terms of what I retain. Sometimes I come across YouTube videos that YouTube claims I have watched, and I don't remember the first thing about them. I thi…

There might be a market for this.

Re: Lessons by 3blue1brown

#74

Post by jameshart »

beambot wrote: post #61
jameshart wrote: post #51

Earlier quoted context omitted.

That doesn’t provide the full understanding you might think it does. For example: define ‘right now’. Instantaneously, music is a single sound pressure measurement. That doesn’t have a Fourier transform. It doesn’t have a frequency. It’s just a single sample. Fourier transforms work on functions. Typically functions in the time domain. And typically (but not always) on that function within a bounded range of time. An…

I think I get what you are trying to say... but the intuition about "this moment in time" is perfectly reasonable for a spectrum analyzer, since it's actually doing a DFT (not continuous from +-infinity) with the last sample (i.e. "now") defining the end of the window.

The thing that makes a DFT discrete is that it is over individual samples rather than a continuous function - not that it is over a finite domain.

A Fourier transform applied to a brief window of an underlying continuous function is called a ‘short-time Fourier transform’.

And the frequency information a STFT can pick up is bounded on the low end (think, like the opposite of the Nyquist limit) by the length of the window - this is called the ‘Rayleigh frequency’ - if your window is of length t, you can not detect frequencies lower than 1/t. Which is why your ‘instantaneous’ spectrum analyzer (looking at a short burst of maybe 0.05s of samples) for your 120bpm EDM doesn’t pick up a frequency component at 2Hz - even though that component is there in a Fourier analysis of the whole piece. It can only measure down to 20Hz. Which is fine because that’s also roughly the limit of the part of the song ‘function’ that we hear as ‘tone’ rather than ‘rhythm’.

Re: Lessons by 3blue1brown

#75

Post by hwestiii »

postsantum wrote: post #4
jackling wrote: post #2

I'm likely in the minority, but I found 3blue1brown videos difficult to understand and they usually give me a worse intuition about a concept than I previously had. I wonder why that is. Seems like most people I know swear by his videos.

Any alternatives to recommend?

Numberphile is good, but more "crowd sourced".

Re: Lessons by 3blue1brown

#76

Post by phkahler »

JackFr wrote: post #29
coreyp_1 wrote: post #20

Earlier quoted context omitted.

Learning is all about using your current knowledge and understanding to refine and augment those mental models. Be aware that many people don't watch videos to learn, they watch to be entertained. They think that they are learning, but really they are just watching animations. In the end, they can't actually do any of the math. They haven't actually learned anything. In the same vein, that's why TED talks are so popu…

Professor I had for Real Analysis (the second time I took it) was probably the best math professor I've ever had. He had the most extensive mental catalog of the wrong ways people could understand and the failure modes of students. When you would ask a question he was able to help, not just because he understood the material, but because he knew why you didn't. In my evaluation of him I mentioned this, but added that…

>> When you would ask a question he was able to help, not just because he understood the material, but because he knew why you didn't.

When my high schooler come to me with math problems, the first thing I do is look at the failures and figure out what higher level step or concept is missing in the brain. Then I explain that, sometimes more than once with different approaches. Once the higher level thing clicks, I can just sit back and mostly watch.

Sometimes I'm not sure how a concept clicked, but something did and the right answers start coming out.

Re: Lessons by 3blue1brown

#77

Post by jackphilson »

dingosity wrote: post #7

2b1b does a video on how you raise e to a matrix (hint: raising something to e is converted into another function where it's not nonsensical to do such a thing.) In about 10 minutes he explains something my math methods instructor struggled with over two weeks (4 classes). I was resistant to the view that YouTube could host "decent" instructional content for a long time. That video was one of the first that was CLEAR…

perhaps we should remodel our educational system towards content that had a great deal of time spent creating it rather than a slideshow created last night. if only there was this medium that allowed information to be duplicated all over the world instantly so that every professor doesn't need to create their own content

Re: Lessons by 3blue1brown

#78

Post by udev »

liorben-david wrote: post #54

Let me preface what I'm saying by just expressing gratitude to 3b1b for making an amazing math animation library, getting tons of people excited about math(Including me), and producing some really great videos to give people intuition. All that being said, I've found that 3b1b videos tend to bound the intiution you can get on a topic. Most of his videos tend to reframe an idea in some sort of interesting way that can…

This reminds of Richard Feyman's observation how some people count visually while others do it by sound.

You might be one of those people that can do math purely symbolically, by parsing and manipulating expressions, a bit like regular language and you don't need your brain to build a mental image for the things you work with.

I am intuition-first kind of person, and let me tell you, intuition is not a crutch, it can do things where symbol manipulations would take orders of magnitude more effort.

It is actually possible to imagine and manipulate highly-complex, multi-dimensional things that don't have equivalents in nature.

Imagination is a muscle used a lot when thinking intuitively, some of us have it developed to a ridiculous degree.

Re: Lessons by 3blue1brown

#79

Post by GrqP »

haberman wrote: post #38

I would love it if some of these educational YouTube videos came with exercises. I watch a lot of educational YouTube videos. But I've come to see them as more entertainment than education. Not in terms of the quality of the videos (which is often excellent), but in terms of what I retain. Sometimes I come across YouTube videos that YouTube claims I have watched, and I don't remember the first thing about them. I thi…

I'm in the same boat.

Although I find instructional videos helpful in understanding concepts, the knowledge is fleeting. Exercises would be helpful, but IMHO, sometimes you need the support of a cohort or TA to solve problems in a different way.

MOOCs are pretty good. They have instructional videos, exercises and a cohort. Still, they seem to be missing something. AI will push online learning to 2.0.

Re: Lessons by 3blue1brown

#80

Post by LordDragonfang »

Silverback_VII wrote: post #28
armchairhacker wrote: post #9

3b1b is doing everyone a huge favor with these lessons. Teaching is certainly a lot different today. Decreased attention spans, underfunded schools, and ChatGPT make it a lot harder, but online modules and tutorials like these make it a lot easier.

The problem is that you can learn many things, but time is limited. Learning and understanding abstract concepts won't make you more successful, increase your SMV and give you access to better mating opportunities. What's the use of arcane knowledge about prime numbers if you are not mathematician, and even then, one should question its importance? Time is often better spent learning about crucial factors of success…

As a counterpoint to what you've said, doing things to increase your understanding of the language of the universe can lead to a more fulfilling life than a myopic focus on your... "sexual market value".
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