Communities

Writing
Writing
Codidact Meta
Codidact Meta
The Great Outdoors
The Great Outdoors
Photography & Video
Photography & Video
Scientific Speculation
Scientific Speculation
Cooking
Cooking
Electrical Engineering
Electrical Engineering
Judaism
Judaism
Languages & Linguistics
Languages & Linguistics
Software Development
Software Development
Mathematics
Mathematics
Christianity
Christianity
Code Golf
Code Golf
Music
Music
Physics
Physics
Linux Systems
Linux Systems
Power Users
Power Users
Tabletop RPGs
Tabletop RPGs
Community Proposals
Community Proposals
tag:snake search within a tag
answers:0 unanswered questions
user:xxxx search by author id
score:0.5 posts with 0.5+ score
"snake oil" exact phrase
votes:4 posts with 4+ votes
created:<1w created < 1 week ago
post_type:xxxx type of post
Search help
Notifications
Mark all as read See all your notifications »

Activity for Mithrandir24601‭

Type On... Excerpt Status Date
Edit Post #282648 Post edited:
Edited title so Latex doesn't overflow
over 3 years ago
Edit Post #281987 Post edited:
fixed latex formatting
over 3 years ago
Comment Post #281586 Whether or not it's off-topic is up to the community - for reference, we created a category on physics for 'problems', where people essentially ask for help with their attempts to whatever problem (not 'the solution', just help), which is similar-ish to the idea of homework and exercises
(more)
over 3 years ago
Edit Post #280857 Initial revision almost 4 years ago
Answer A: Don't downvote just because someone posted screenshot.
For various reasons, people need to use screen readers. To my knowledge, screen readers can't read text from images, so this is an accessibility issue. In addition, some people might just find it hard to read text in images. While there's nothing wrong with using screenshots, it is important t...
(more)
almost 4 years ago
Comment Post #278558 Worth mentioning that the paper has now been taken down as they were detecting "dead time in the NuSTAR detectors". This is apparently "further evidence for why standard timing methods should not be used with NuSTAR data"
(more)
about 4 years ago
Comment Post #278638 I'd added an additional (yet more convoluted) edit that should explain in more detail what's going on but honestly, 'it's required because $10nx - x$ is an integer' is by far the best answer because this whole 'left concatenation' process follows immediately and directly from that. Call it a geometri...
(more)
about 4 years ago
Edit Post #278638 Post edited:
about 4 years ago
Comment Post #278638 "with change ... the change being what needs to be added to digits further to the left." Is this carrying over process. What more do you want me to say? All you're doing is multiplying a digit by n and shifting it to the left one place. Repeat, summing everything up, this is *precisely* what's going...
(more)
about 4 years ago
Comment Post #278638 I've updated my answer (although honestly, I feel that the first bit is about 100 times clearer). I've included the bit about the powers of $n$ and what you're referring to as 'backwards concatenation' is what I'm referring to as 'multiplying a digit by $n$ to get the digit to the left'. It works bec...
(more)
about 4 years ago
Edit Post #278638 Post edited:
about 4 years ago
Edit Post #278638 Initial revision about 4 years ago
Answer A: Why does the decimal expansion of $1/(10n - 1)$ have this neat pattern?
First of all, there is indeed a pattern. To figure out why, there's an easier example than what you've found: $$0.\bar{1} = \frac{1}{9}.$$ How does that work? $1$ is the only power of $1$: $1^n = 1$. Now, how do we prove this? if $x = 0.\bar{1}$, then $10x = 1.\bar{1}$ and so, $9x=1$. Hid...
(more)
about 4 years ago
Comment Post #278553 Except that's not what I'm doing here, so why is that relevant to the question?
(more)
about 4 years ago
Comment Post #278553 I'm not sure who told you that, but we [really don't](https://en.m.wikipedia.org/wiki/Degree_of_coherence#Degree_of_first-order_coherence) - is useful *because* it doesn't average over time (or frequency if that's your thing). In classical physics, $g^{(2)}$ is intensity correlations. Anyway, this qu...
(more)
about 4 years ago
Comment Post #278553 See my comment [to this answer](https://math.codidact.com/a/278553/278562) - we're generally not time averaging anything - the expectation values are taken at specific spatial and temporal locations
(more)
about 4 years ago
Edit Post #278553 Initial revision about 4 years ago
Question Which of the multiple definitions of correlation to use?
In optics[^1], we have a notion of coherence, that's defined as a normalised correlation/cross-correlation/autocorrelation function: Simplifying notation from the linked Wiki page we can write the (un-normalised, first order) correlation function $$G^{(1)} = \left\langle XY\right\rangle,$$ where I'm ...
(more)
about 4 years ago
Edit Post #278114 Post edited about 4 years ago
Edit Post #278114 Post edited about 4 years ago