Activity for Peter Taylorâ€
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Comment | Post #285984 |
Quaternions are not complex numbers. The complex numbers can be seen as a subalgebra, but I'm not sure to what extent that is useful or helpful. (more) |
— | about 2 years ago |
| Comment | Post #285671 |
Have you drawn a diagram of the squares in question? (more) |
— | over 2 years ago |
| Comment | Post #285015 |
@#55022, if you have a property which you do not find intuitive or counter-intuitive then you need a very good reason for believing that it *should be* intuitive to justify the question. Axioms and definitions are chosen and become popular because they're *useful*, with no guarantees about how intuit... (more) |
— | over 2 years ago |
| Comment | Post #285425 |
My impression (and I haven't just rechecked the question list to validate it) is that very few of the questions are at a level of needing a grad student to answer them. It's probably fair to say that those which *are* at that level are mostly unanswered, but it's also probably fair to say that that *... (more) |
— | over 2 years ago |
| Comment | Post #285342 |
Closed as off-topic because the issue at heart here isn't mathematics but linguistics. In particular, what a good answer would address is the flaws in assuming firstly that a word has only one meaning, and secondly that whoever made that YouTube video is the absolute authority on what that meaning is... (more) |
— | over 2 years ago |
| Comment | Post #285086 |
I don't think that MCD is "based on" either site, but my point is that its scope is similar to MSE's and so it's not a surprise that it has the same problems as MSE. (more) |
— | over 2 years ago |
| Comment | Post #284996 |
That graphic helps a lot, thanks. But if the two initial squares aren't horizontally or vertically adjacent, it's not clear that the border is well defined. You can draw the 8-square box around each one, and then connect appropriate corners of the boxes with straight lines, but deciding which squares... (more) |
— | over 2 years ago |
| Comment | Post #284996 |
The notation can be read "the set of points $(0, t)$ where the variable $t$ is between $0$ and $1$ inclusive". It's just the line segment (technically not a line, because lines are infinite) between the two points. (more) |
— | over 2 years ago |
| Comment | Post #284996 |
This seems to be getting less clear, not more. Take a concrete example: let the two points be $(0, 0)$ and $(0, 1)$. What is the "minimal border" if not the line segment $\\{(0, t) \mid 0 \le t \le 1\\}$? (more) |
— | over 2 years ago |
| Comment | Post #285015 |
Turn the question around: what is *unintuitive* about it? (more) |
— | over 2 years ago |
| Comment | Post #284996 |
The area of a circle is $\pi r^2$, and a point is the limit of a circle as $r \to 0$. (more) |
— | over 2 years ago |
| Comment | Post #285005 |
If the question is "Why does dividing two equal things by the same thing give two equal things" then I'm not sure why that isn't intuitive already. Separately, the first image gives a false statement (because you always need to be wary of the special case of division by zero), and I'm not sure what t... (more) |
— | over 2 years ago |
| Comment | Post #284997 |
I can't even guess at what you're asking. (more) |
— | over 2 years ago |
| Comment | Post #284773 |
@#54114, when r~~ gave essentially the same answer in comments saying that it wasn't clear whether it was what you were looking for, your response was much more lukewarm. (more) |
— | over 2 years ago |
| Comment | Post #284550 |
Is "transpose matrix" a technical term from some field (perhaps mathematical physics) or should the tag be changed to `matrix-transpose`? (more) |
— | over 2 years ago |
| Comment | Post #284561 |
If you're asking about notations that physicists use, you might have a better chance of getting a good answer on the physics site. (more) |
— | over 2 years ago |
| Comment | Post #284651 |
You can easily calculate the expected steps per roll as 1.68. To reach a million steps you're going to need at least 20000 rolls, and an estimated 595238 rolls. Is there anything which you can't calculate to sufficient precision for your purposes just using the central limit theorem? (more) |
— | over 2 years ago |
| Comment | Post #284550 |
`$\tilde{e}$` gives $\tilde{e}$ (more) |
— | over 2 years ago |
| Comment | Post #284052 |
You seem to be amalgamating two orthogonal issues: citing the source of the material which the question is about, and establishing some kind of whitelist of acceptable sources. IMO the first is a reasonable issue to raise and the second is an unreasonable suggestion, but the discussion would be clear... (more) |
— | over 2 years ago |
| Comment | Post #283952 |
Yes, that's what I said in my comment yesterday. (more) |
— | over 2 years ago |
| Comment | Post #283935 |
@#53922 I think (although without more context I can't be certain) that you're misunderstanding the flow of the text. It looks to me as though (2.6) states a condition (which you've misquoted in your comment: that subscript $\alpha = 0$ is there for a reason) and then the following text, from "By the... (more) |
— | over 2 years ago |
| Comment | Post #282564 |
@#54204, I'm not sure what suggested edits you're talking about. (more) |
— | over 2 years ago |
| Comment | Post #283886 |
I don't think it's a duplicate as such, but you asked a [previous question](https://math.codidact.com/posts/282771) on a later sentence from this exact passage from your textbook (and Wolgwang kindly replaced your image with text and MathJax there, which you could reuse here). (more) |
— | over 2 years ago |
| Comment | Post #283899 |
@DNB, your teacher seems to have a vocabulary full of obscure English words which reference supernatural beings or supernatural knowledge of the future (*soothsay*, *augure*, *fey*, *sibylline*, *vaticinate*), but that vocabulary isn't suitable for use (a) in mathematics; (b) with native English spea... (more) |
— | over 2 years ago |
| Comment | Post #283400 |
Hint: you can find the answer near the start of the [Wikipedia page on matrices](https://en.wikipedia.org/wiki/Matrix_\(mathematics\)). (more) |
— | over 2 years ago |
| Comment | Post #283399 |
@#53628, it's not an unreasonable assumption that someone with questions about material at this level is in full-time education and has access to a teacher. (more) |
— | over 2 years ago |
| Comment | Post #283339 |
You do realise that this is the Mathematics site, not the Physics one? (more) |
— | over 2 years ago |
| Comment | Post #283299 |
Yes, and then we can see how well the "revert to previous version" feature is implemented. (more) |
— | over 2 years ago |
| Comment | Post #283254 |
Does this really need two questions? There are marginal differerences to the other one, but really they're both asking for explanations of the same diagram, and if there's any answer other than "If that explanation doesn't help you, find a better one" then it's probably better in one place rather tha... (more) |
— | over 2 years ago |
| Comment | Post #282600 |
What makes you think that "*these authors and publishers are desperate for income*" as opposed to unsatisfied with the alternatives? (more) |
— | almost 3 years ago |
| Comment | Post #283086 |
Firstly, I don't see anything in the T&C on the physicsforums site which says that content is CC0-compatible, which is why I've deleted your self-answer. But secondly, even if it were, it's almost always better to write an answer in your own words once you've understood the solution to a more than su... (more) |
— | almost 3 years ago |
| Comment | Post #282645 |
This question at present is completely different to the question originally posted and to which my previous comment applies. Recycling a question ID like that is a source of confusion. What's going on? (more) |
— | almost 3 years ago |
| Comment | Post #283086 |
That sounds very broken. DuckDuckGo in an incognito browser window gives me a useful result from Wolfram MathWorld as the very first result. (more) |
— | almost 3 years ago |
| Comment | Post #283086 |
What does your favourite search engine say? (more) |
— | almost 3 years ago |
| Comment | Post #282658 |
@#8046 , go ahead. (more) |
— | almost 3 years ago |
| Comment | Post #282658 |
I won't pretend to be enthusiastic about the idea, but I recognise that in small communities it's sometimes necessary to serve a term in office as a public duty. I have no prior experience as a moderator *per se*, but in another place I did have maximum rep-based privileges unlocked on one site and m... (more) |
— | almost 3 years ago |
| Comment | Post #282642 |
If the quoted exercise is the true problem and this is an XY question, it's far simpler to consider the basic combinatorial meaning of $\binom{n}{k}$. (more) |
— | almost 3 years ago |
| Comment | Post #282645 |
Probably not. But if you interpret $\sum_{k=0}^n k \binom{2n}{k}$ in terms of choosing a team of up to $n$ people with one designated captain from $2n$ people then you can transform it into a sum which you're already familiar with. (more) |
— | almost 3 years ago |
| Comment | Post #281319 |
@DNB, the sum total of your edits seems to be to remove all MathJax content. If you refer to explaining to a primary school pupil, I think the correct response is probably "The subject is too advanced. Wait a few years," but since I've never tried to teach maths to primary school pupils I may be unde... (more) |
— | almost 3 years ago |
| Comment | Post #282286 |
You ask whether questions "like these" are considered on-topic, but give the example in a format which only moderators can actually read (a link to a deleted question). That doesn't seem very productive. (Although, FWIW, my attempt to reconstruct the question from clues in this meta-question suggests... (more) |
— | almost 3 years ago |
| Comment | Post #281724 |
Would I be correct in guessing that the lack of any comment on my answer is because you haven't seen the final version? (more) |
— | almost 3 years ago |
| Comment | Post #281987 |
This appears to be exactly the same as your earlier question https://math.codidact.com/posts/280741 , and certainly suffers the same flaw that I raised then in the comments which makes it unanswerable. (more) |
— | almost 3 years ago |
| Comment | Post #280851 |
Do you have a definition of $\lim_{a \to \infty} f(a) = \infty$ in first order logic (i.e. as a simple statement with $\exists$ and $\forall$)? (more) |
— | about 3 years ago |
| Comment | Post #280741 |
How are you quantifying "contrast the base rate fallacy"? (more) |
— | about 3 years ago |
| Comment | Post #280639 |
@TechnologicallyIlliterate, yes. The wording around arbitrary constants and families of solutions indicates that you need to be more careful than just eliminating the common $y$. The $c$ is (32) is not necessarily equal to the $c$ in (33). (more) |
— | over 3 years ago |
| Comment | Post #278332 |
For $n=3$ you want three rectangles of 1/3 by 1. Beyond there it gets more complicated; I suspect that the initial cuts will tend to leave a rough circle, but if so then IIRC some calculations I made a few months ago showed that the diameter of a sector sliced from the circle would eventually be grea... (more) |
— | over 3 years ago |
| Comment | Post #280068 |
@Derek Elkins, I would say that the key difference is that division by 2 isn't really division in binary floating point representations: it's subtraction applied to the exponent. (I'm sure you know this already, but I didn't think it came through clearly in the explanation). (more) |
— | over 3 years ago |
| Comment | Post #280118 |
To be clear: am I correct to understand that by "*the last two points*" you mean everything from "*and we define*" until the end? (more) |
— | over 3 years ago |
| Comment | Post #279400 |
What is the division ring in your "intuitive" instantiation? (more) |
— | over 3 years ago |
| Comment | Post #278431 |
Or the property $P(x) = x \not\in x$ cannot exist in such an axiomatic system, or such an axiomatic system can contain a set of all sets but at the cost of consistency, or possibly such an axiomatic system can contain a set of all sets as long as it doesn't have the law of the excluded middle. (more) |
— | over 3 years ago |
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