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Decades-Old Computer Science Conjecture Solved in Two Pages

quantamagazine.org

61–70 of 74 posts

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#61

>the new proof is so simple that one researcher summed it up in a single tweet. Didn't look that simple to me! Reminds me of Andrew Ng showing his students the simple one liner to solve the cocktail party problem in Octave. There's a lot represented in that one line of code!

Where is the tweet?

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#62

>the new proof is so simple that one researcher summed it up in a single tweet. Didn't look that simple to me! Reminds me of Andrew Ng showing his students the simple one liner to solve the cocktail party problem in Octave. There's a lot represented in that one line of code!

Where is the tweet?

The words "single tweet" link to it in the article.

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#63
post #57

Earlier quoted context omitted.

I read that, but I believe that's describing the problem. Anyone care to explain the answer in a similar simple way? Actually one thing weird wiht that explanation is they call sensitive bits the ones that don't change the output? You'd think it would be the red ones

That is the solution! See? It's so simple it seems like a formulation of the problem itself! The solution is to think of the input ('001') in terms of an n-dimensional cube, where n is the length of the input. So for example, a binary logic with 5 bits ('01010') would require a 5-dimensional cube. From there, you check whether moving from one input ('00001') to an adjacent input ('00011') causes a flip in the output.…

Interesting... so what does a "5 dimensional" cube look like? I am having difficulty visualizing that

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#64
post #63

Earlier quoted context omitted.

That is the solution! See? It's so simple it seems like a formulation of the problem itself! The solution is to think of the input ('001') in terms of an n-dimensional cube, where n is the length of the input. So for example, a binary logic with 5 bits ('01010') would require a 5-dimensional cube. From there, you check whether moving from one input ('00001') to an adjacent input ('00011') causes a flip in the output.…

Interesting... so what does a "5 dimensional" cube look like? I am having difficulty visualizing that

4 took me hours. Give up any visuals.

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#65
post #63

Earlier quoted context omitted.

That is the solution! See? It's so simple it seems like a formulation of the problem itself! The solution is to think of the input ('001') in terms of an n-dimensional cube, where n is the length of the input. So for example, a binary logic with 5 bits ('01010') would require a 5-dimensional cube. From there, you check whether moving from one input ('00001') to an adjacent input ('00011') causes a flip in the output.…

Interesting... so what does a "5 dimensional" cube look like? I am having difficulty visualizing that

An easier way to think of it is just as a matrix where each vertex is connected to n other vertices. The reason an n-cube is used specifically is because the bits correspond to spatial coordinates, which obviously require a uniform structure (like a cube if we're talking 3D) in order to make sense.

This[0] article might help though.

[0] https://en.wikipedia.org/wiki/5-cube

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#66

Surprisingly good for a Quanta Magazine article.

It's an important and interesting but unusually simple mathematical topic that can be explained quite well without dumbing it down, leading to a "surprisingly good" article compared to scientific divulgation in general.

What is the importance of such problem in real life?

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#67
post #63

Earlier quoted context omitted.

Interesting... so what does a "5 dimensional" cube look like? I am having difficulty visualizing that

An easier way to think of it is just as a matrix where each vertex is connected to n other vertices. The reason an n-cube is used specifically is because the bits correspond to spatial coordinates, which obviously require a uniform structure (like a cube if we're talking 3D) in order to make sense. This[0] article might help though. [0] https://en.wikipedia.org/wiki/5-cube

Thank you!

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#69
post #59

Earlier quoted context omitted.

From the article: > Other measures involve looking for the simplest way to write the Boolean function as a mathematical expression, or calculating how many answers the banker would have to show a boss to prove they had made the right loan decision. There’s even a quantum physics version of query complexity in which the banker can ask a “superposition” of several questions at the same time. Figuring out how this measu…

I'm not seeing the connection between this research and fixed-point arithmetic.

I don’t exactly follow the above either, but I believe fixed point is meant in a different sense here, as in a function f(x) such there a point x0 exists where x0=f(x0).

https://en.m.wikipedia.org/wiki/Fixed-point_theorem

Re: Decades-Old Computer Science Conjecture Solved in Two Pages

#70
The history of computer science is dauting. Unlike physics, though, it's the history of incremental innovations that culminated in what we have today. Thus, if you go back in time long enough, things eventually are manageable.

A good primer on the history of CS is probably Code, The Hidden Language of Computer Hardware and Software, by Charles Pretzold. I've put together some notes on it here: http://alvaroduran.com/code.

Any feedback is much appreciated!

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