Can there be a priori truths for science?

Question: Can there be a priori truths for science, even if science is heavily based on the scientific method with empirical evidence? What if we're using examples like theoretical physics? Please explain.
Answer: See A Priori :

"A priori" and "a posteriori" refer primarily to how, or on what basis, a proposition might be known. In general terms, a proposition is knowable a priori if it is knowable independently of experience, while a proposition knowable a posteriori is knowable on the basis of experience.
A priori justification [of knowledge] has thus far been defined, negatively, as justification that is independent of experience and, positively, as justification that depends on pure thought or reason.

Having said that, if we consider the most abstract empirical sciences, like theoretical physics, whose axioms are very far from mere "generalizations from experience", it is hard to maintain that there is no some sort of empirical support for them.
Without the complex network of experiences, experiments and theoretical predictions built up by scientists during some centuries of inquiries, it is difficult to imagine that someone can "devise" in a purely a priori manner theories like Relativity or Quantum Mechanics.
Comment: thank you. So do you mean that Relativity and Quantum Mechanics are a priori?
Comment: @CCC - not at all... "it is difficult to imagine that someone can "devise" in a purely a priori manner theories like Relativity or Quantum Mechanics."
Answer: We tend to label a priori truths in science as Mathematics, instead of being part of any given Science, even when the mathematics is evolved directly for a given scientific purpose, like calculus for Newtonian dynamics and the second generation of statistics for biological testing.
But most of the content of Mathematics is a priori.  We can see this because when we find that it does not fit the outside world, it does not become false, just less-used.  Any a posteriori argument simply has no force against its 'truth', only against its 'applicability'.
If mathematical constructs must be derived to make sense of a theory, that material is a priori.  The scientific theory itself then is a posteriori, in that it will deploy the mathematical mechanics against actual observations.  The theory might fail, end yet the math might live on and find a different application entirely.
I would suggest this is because the mathematics is dredged up out of human intuition through idealizations that are made about observations rather than observations themselves.  The ideal forms simply are not true of the observations themselves.  But they are the simplified forms that appeal to human psychology, which is "from before" the data.
From that point of view: Celestial mechanics is not a priori, but the Calculus is.  Relativity may not be a priori, but tensor theory is.  Quantum mechanics may not be a priori, but matrix mechanics is.
Answer: A priori truth is a knowledge obtained before and independent from experience.
The issue of a priori truth for any kind of science has first been investigated by Aristotle in Book 1 of his Metaphysics. From today's point of view the only a priori truths of science are the rules of logic and the syllogisms of logic: The law of non-contradiction has already been stated by Aristotle.
Kant - deeply impressed by Newtonian mechanics - claimed that natural science like Newtonian mechanics also disposes of a priori knowledge. See his work Metaphysical Foundations of Natural Science (1786).
Today his claim is rejected by the scientific community. Today's science is much more cautious. As you write, science always starts by observation and experiment. All general knowledge is considered hypothetical. It can be confirmed by observation but not proved. It can can always be refuted by new experiments. Then the underlying theory has to be improved or replaced by a new theory.
Hence the only a priori truths of science belong to the domain of logic.
Answer: The principle of inertia seems to be a good candidate for an "apriori truth": it is never verified and connot be verified positively, but explanations are adduced why  a certain body does not continue its regular movement to infinity.
The conservation of energy was also considered a good candidate and different kinds of energies have been introduced in order to save it. (Feynman has memorably written on this topic.) Recently people have started to argue that it does not apply for the universe as a whole; however, appealing to symmetry and eventually explaining why it is not observed still seems to be a kind of aprioristic stance.
So, one might like to argue that principles are apriori ruths.
Comment: why can the principle of inertia never be verified? @sand1 If we have felt inertia, e.g. in a moving car and when it suddenly stopped our body seems to be moving forward, then isn't that then become a a posteriori truth?
Comment: The whole point of the *principle* is the passage to the limit: what is true up to the limit may  or may not be true at the limit. Proceeding scientifically and empirically as Aristotle will teach you that sooner or later movements are exhausted: experience is finite and non-ideal in contrast with the conditions for the principle which is taken to be true. See Popper and Lakatos.
Comment: You are wrong about the principle of inertia. The principle of inertia claims that in a force free system in an inertial frame moves in a straight line at constant speed. (I am leaving aside complications from general relativity and that sort of thing.) You can't make predictions using the poi without also giving an account of what forces are present but that doesn't make the principle untestable. Rather, it is tested by considering theories that conform to it and theories that don't and seeing which set stands up to critical scrutiny. Likewise for conservation of energy.
Comment: I agree you are not quite on point with inertia, but I get your direction.  You might try reaching back farther.  A concept like 'mass' independent of 'weight' might be considered 'a priori'.  You cannot feel mass, and it is independent of the things it was idealized out of, including weight, inertia, and other abstract notions of size.  The problem then is that we historically have communicated this 'a priori' notion by distilling 'a posteriori' concepts down to what they have in common, and finding a more basic intuition independent of their details, which is kind of 'a post-post-posteriori'
Comment: Conservation of energy has the same disease.  Early thinkers had no problem with gods just creating things.  But we distilled all of this apparent new creation down into something more abstract, which then became very compelling.  So is that underlying intuition more basic, or more constructed?
Answer: A useful contrast is a priori with a posteriorai; and to take each as a kind of ideal point.
Arguments in science can be closer to either in this continuum.
Consider what constitutes a definition of force in Aristotle - though he doesn't use the word:

it is that which has the capacity to cause change, and can actually cause change in another; and this by contact; and that another has the capacity to be changed, and can actually be changed.

This, though doubtlessly by A is based on experience; elsewhere for example, A says:

as for movement, it would be strange if we failed to notice the downward motion of a stone; nor do we fail to notice it is at rest on the Earth.

Which, does make A sound as though he was reacting, as a theorist of physics, here, to a critique of 'armchair' theorising by the wholly empirically minded; a critique that is just as much levelled today, as much as then.
It's also possible, I think, to discern here, the historical mythos of Newtons falling apple - which every schoolboy learns, and then has to unlearn - and which mythically prompted his thought towards gravity; though on the evidence above, it seems a well prompted and fruitful observation.
Comment: @ccc: they work as a dialectic of two; so are often in tension and territorialised by each other; there are various sites where the cases you suggest occur; something which I didn't mention in the answer above, by the way; is that there are different senses of *a priori* - there's the Kantian notion, and Aristotles for example - and Aristotle has at least two; the physical kind, noted above; and a logical one.
Comment: So @Mozibur Ullah, in your opinion, do you think in Science, a priori works with a posteriori. A priori lay the groundwork for the deduction of the hypothesis, then a posteriori to observe the real-life implication? Or do you think they are exclusive and cannot happen together?
Answer: Beautiful question: yes, there's an a priori knowledge: causality. Everyone knows nature's mechanism of action and reaction, cause and consequence. Since we start existing inside the mother's belly, we make stimulus and get reactions. We know that. Nature works with that. Math describes that perfectly, because causality has been perfect (until quantum mechanics found some incoherences). We speak and interact following the causality mechanism.
The mechanisms of causality are related to systems -all things-. There is no cause if there is no system over which to apply it. So, knowledge is built over this a priori base: actions and reactions we clearly identify over things we are familiar with.
This is a topic of the systems theory, and I'm an author working on the subject, so please consider this as an opinion. I write about this because the systems theory requires this kind of adjustments, in the meantime, it's heavily incomplete.
Answer: Every empirical science has an a priori foundation.
If a proposition is a priori, it means it's not justified by experiments.
Any proposition is supported by one or more principles.
Principles are foundational truths which are not deduced from any other (that's why we call them Principles).
If every proposition had to be deduced from another, that would create a problem of infinite regression and no proposition would ever be justified.
Principles are a priori in the same say Logic is.
The Principle of Non-contradiction described by Aristotle in his Metaphysics is assumed to be valid in every empirical science. Thus, every empirical science has an a priori foundation.
Therefore, in answer to your question: there can be no science without a priori truths!


The Best Option For Recording, Playback and Storage re: Hard Drives?

Question: A few months ago I shifted my "Audio' folder to my external hard drive (WD 2TB Studio Edition 2). It has FW400, 800 and eSATA connections. Im currently using FW800 soon to be using eSATA (once I get the driver info from the supplied mini CD that wont fit into my MacbookPro laptop). I use the external drive for all (not just audio) my storage and record/playback too. It is currently approx half full. I often have playback issues when playing a ProTools session. ProTools suggests changing my buffer settings etc yet this doesn't really solve the issue. I've recently partitioned the External Drive to 4 sections. One partition is now dedicated to Audio (for recording, playingback and storage/management). Yet, ProTools is still often freezing when playingback but with a differnt message. Now saying my connection to the hd is either not fast enough or the drive is partitioned..I (maybe wrongfully) assumed that a partitioned drive would make it quicker to search the audio folder for the data needed. So, my questions:
Does partitioning help speed the process up of searching for the info or should i go back to no partitions?
Will the eSata connection solve the issue by increasing the transfer rate?
or should I be using the internal drive for recording and playback and the external for storage/editing?
ps: reminding you I have a Macbook Pro laptop which only has 1 internal drive (if this is relevant?)
Any help is greatly appreciated:)
Comment: @SoundsGood - When you say "I use the external drive for all (not just audio) my storage"- what else are you reading off the drive?

Partitioning should increase performance if anything..
Comment: @James. I have a Film, TV and Other partitions. So four in total. films and tv episodes and all my personal things.
Answer: Dedicate a single drive for audio only, partitioning is not the answer.  Use as small a drive as possible so that the access times are really fast and remember to wipe free space periodically.  Use your large hard drive for back ups.
Answer: Partitioning will not speed up your read or access speed at all. The drive still turns at the same speed (7200rpm in the case of this particular drive), and it still has the same number of heads to read data. All the partition is going to do is help keep your data better organized. If you're not using the "audio" partition when performing other tasks, then data won't be written to that area of your disc. Less data=less clutter (aka fragmentation)...which is not a bad thing at all, but I don't think it will help your buffer idea.
Try limiting the record time available for your sessions in Pro Tools. The software actually operates better if you tell it to reserve a certain amount of space on your hard drive and work within that, than it does if you give it free reign over all of the free data sectors. You can set this by going to the "Operation" tab of the preferences menu. In the there's an option in the "Record" section of that page.
That's all I can think of right now without being in front of your system to see how it's actually behaving. I hope it helps.
Answer: The transfer speed (FW400, 800, USB, etc.) is very important, but the speed (7200rpm vs 5400rpm) of your hard drive plays a huge role in the performance. I'm not sure about the partitioning but it may be a good idea to use your internal drive for current projects and transferring what doesn't need constant access to your external drive.
Answer: Hey @mrchegibson, do you also have your pro tools session files in this external drive? words says it could get messy if you have the session files in one drive and the samples or other media in another one.


No splash screen after installing nvidia drivers

Question: Elementary OS splash screen has dissapeared after installing nvidia drivers, is there an easy way to restore it? I´ve read some tutorials for Ubuntu but they're hard to follow and results weren't guaranteed. Thanks for your help.
Answer: Step 1.
Use Ctrl+Alt+F1 at login screen to open the root terminal
there you use
apt purge nvidia to remove the nvidia driver and go back to the noveau driver. after that reboot
Step 2.
To install the current stable version of the nvidia driver by writing the current commands in either the root terminal or
sudo add-apt-repository ppa:graphics-drivers to add the driver repository to the list
sudo apt-get update to update your repository list making the repository active
After that use sudo apt-get install nvidia-387 to get the latest driver.
If that doesn't work redo step 1.


What can be done about the calendar app closing itself on an iPad?

Question: I have been using my calendar fine but this afternoon when I click on the tile it briefly opens (1 sec) and then closes itself. I have waited 30 mins, I have turned iPad off & back on and still no joy.
Answer: This is how applications crash on iOS - so you may want to check your settings to see if your iPad is sending crash reports to Apple.
Settings App -> General -> Diagnostics & Usage
You can also look in the Data submenu from the above screen and scroll down to look for LatestCrash.plist and see if the date matches when your iCal quit.
In general, it's not possible (even as a developer) to read these reports without access to the iCal source code and you have some short term things you can do to isolate the issue further.
First is to remove any notifications (turn of WiFi and cellular data) and reboot the iPad. If iCal crashes, then it's due to the calendar data on the device and not some external cause. You can then remove your calendar information, account by account to clear up which account has the data corruption that is causing iCal to have a problem. Worst case, you will have to connect your iPad to a computer (iTunes) and force a sync to erase the calendar data on the iPad and replace it with data from the computer to clear the data that is causing the crash.
Apple will likely fix the crash (even with bad data - the program should handle it and let you know an event is broken or ignored and why) in the upcoming updates - but you can report the crash to add weight to this particular bug getting fixed.
You can also take an overkill (but faster) approach to erase all content and settings on the iPad and set it up again.
It's unlikely the data will come back corrupt from your calendar sources (or the backup) but if it does, at least you'll know a bit more about how to isolate which calendar is causing iCal to have problems.
Comment: Thank you very much for the answer, i have isolated it to one particular month and going through your suggestions.
Comment: If you end up isolating it by hand, look up Binary search if you have more than ten items in that month to save time finding the problem. Also, attachments and attendees are generally more likely to be corrupt or cause issues.
Answer: Sounds like the April 1st calendar crash. Delete whole day events on April 1st (and unsubscribe from calendars that give you public holidays on that day), and that should fix crashes that occur when you go to month view in March.
Answer: Apple support tell me that the problem is known, their engineers are working on it and the temporary solution is to deselect the uk holiday calendar, and by implication any other calendar where events on April 1st are all day, and to change any all day events on April 1st on your own calendars to say 0100 to 2300.
It occurs that people might have several day events stretching over 31st March and 1st April which might also need amending.
Conspiracy paranoids might think the original programmer thought, ahah it's April Fools Day in 2013, but I guess it's more likely to be an unintended consequence of the 31st not having enough hours for a 24 hr all day event.
Answer: If your calendar appears as a blank page and then closes you are unable to delete or change all day events from the 25 hours imposed by daylight saving to fewer hours.
In that case change your location a territory that does not use daylight saving, e.g. Most of Africa. When you reopen Calender you should be able to edit your all day events
Answer: I deleted the subscription to DE Holidays events (German holidays) - and it fixed the problem, even though I have other all-day events listed on April 1.
Answer: Drag the appointment to an empty date. Then you should be able to delete it. Worked for me.
Comment: Are you sure you are answering the right question?


strange inequality involving infinite series

Question: while doing a complex analysis exercise, i came to a strange inequality which i don't know how to interpretate. Suppose you have a sequence $\{a_j\}$ of positive real number. Let $\rho$ a positive real number. The inequality i found after some calculation is
$$\sum_{j=1}^{+\infty}\frac{1}{|a_j|^{\rho +\epsilon}}\leq \sum_{j=1}^{+\infty}\frac{1}{|a_j|^{\rho-\epsilon}}$$
for every $\epsilon>0$.
My question is: can i deduce something from this inequality? for example the convergence of the first series (that with $+\epsilon$)? Can i deduce nothing? Is that inequality surely false?Is it always true, so that i can't deduce nothing in particular?
EDIT: the sequence $a_j$ tends to $\infty$
Comment: If $a_j\to 0\,$ then $\,\frac{1}{a_j}\rlap{\;\;/}\to 0\,$ unless $\,p\pm\epsilon <0\,$ ...
Comment: i've edited, the sequence tends to $+\infty$
Answer: If $|a_j|\geqslant1$ for every $j$ then $|a_j|^{\rho+\epsilon}\geqslant|a_j|^{\rho-\epsilon}$ hence indeed,
$$
\sum_{j=1}^{+\infty}\frac1{|a_j|^{\rho+\epsilon}}\leqslant\sum_{j=1}^{+\infty}\frac1{|a_j|^{\rho-\epsilon}}.
$$
Otherwise no comparison holds (consider the limit $|a_1|\to0$, every other $a_j$ fixed).
But of course, if the series $\displaystyle\sum_j\frac1{|a_j|^{\rho-\epsilon}}$ converges, then $|a_j|\geqslant1$ for every $j$ large enough hence the series $\displaystyle\sum_j\frac1{|a_j|^{\rho+\epsilon}}$ converges as well.
Answer: Basicaly, what you are saying is that if $a_j>0$ and $\alpha<\beta$, then
$$
\sum_{j=1}^\infty\frac{1}{a_j^\beta}\le\sum_{j=1}^\infty\frac{1}{a_j^\alpha}.
$$
This is certainly true if $a_j\ge1$. Since in your case $a_j\to\infty$, this holds for all $j$ large enough. But the inequality is not true in general. Let $N\in\mathbb{N}$ and define
$$
a_j=\begin{cases}
1/2 & \text{if }j\le N,\\
2^{N-j} & \text{if }j< N.
\end{cases}
$$
Then
$$
\sum_{j=1}^\infty\frac{1}{a_j^\beta}-\sum_{j=1}^\infty\frac{1}{a_j^\alpha}=
N(2^\beta-2^\alpha)+\frac{1}{1-2^{-\beta}}-\frac{1}{1-2^{-\alpha}},
$$
which is positive if $N$ is large enough.
In general there is nothing you can deduce from the inequality, since the right hand side can be $\infty$ and the left hand side $<\infty$.
Comment: which is exactly the case, unfortunately....


Can I give a part or full of my zakat to my father who has debt

Question: Can I give a part or full of my zakat to my father who has debt and its increasing day by day for high interest rates.
Answer:
They ask you (O Muhammad SAW) what they should spend. Say: Whatever you spend of good must be for parents and kindred and orphans and Al-Masakin (the poor) and the wayfarers, and whatever you do of good deeds, truly, Allah knows it well.
Surah Baqarah Ayah 215

Yes, you can give your full Zakah to your father until your father's debts are cleared off, or until he is able to bear his expenses by himself.
References:
Can a mother give zakat to her unemployed and poor son?
Is giving zakat to a family member allowed?
Are you allowed to give zakat to your parents or wife?
Answer: Zakat cannot be given to either of the parents. However, you may pay off your father's debt from your money and that will be considered as sadaqa (charity).
My brother, if you have the money to pay off your father's debt, please pay it off. Releasing a person from his debt is a highly appreciated by Allah. And since he is your father and you have the money, please by all means assist him.
And Allah Knows Best.


What is the meaning of ルンパッパ?

Question: I've noticed the word ルンパッパ (runpappa) is used in the KEMU VOXX series of songs, but I don't know how to translate it. Using google translate just returns rumpappa, which isn't an English word. I've tried googling it, but it just returns Ludicolo, which certainly isn't relevant. The top result says it means to sin, but it also says their source may be unreliable. The three songs to use it are Haikei Dopperugenga, Inbijiburu, and Kamisama Nejimaki. Thanks!
Answer: That is a mimetic word to feeling the rhythm of a song.
So translate it into "Rum-pa-ppa".
Rumpappa is the word combined "Run-run" and "Um-pa-ppa"
"Run-run" is a mimetic word expressing good/happy mood.
https://ja.wikipedia.org/wiki/%E3%83%AB%E3%83%B3%E3%83%AB%E3%83%B3
"Um-pa-ppa" is the title of song. This word is familiar with Japanese as they sing it when in primary school.
"Um-pa-ppa" is "Oom-Pah-Pah" in musical "Oliver!".
https://ja.wikipedia.org/wiki/%E3%82%A6%E3%83%B3%E3%83%91%E3%83%83%E3%83%91
Comment: Thanks! I guess it could just be a sound. +1 (even though I don't have enough rep) for a well-constructed informative answer.
Answer: Could this be ウンパッパ? In English, "Oom-pah-pah" is a conventionalised representation of the sound of a large brass musical instrument such as a tuba or trombone. It is the title of a rousing song in the musical "Oliver!", sung in the film version by the great Shani Wallis.

What is the meaning of ルンパッパ？


Why would I export my raw DNA data?

Question: 23andMe, AncestryDNA, and Family Tree DNA all allow you to export your raw DNA results. What is the advantage of doing this? Is there anywhere I can import it for additional analysis?
Answer: There are two reasons:

to secure the data against the (possibly unlikely event) that the company which performed the original analysis ceases to operate or loses your data.
(more important) to import it elsewhere, and so increase the potential number of matches that you make and/or access analysis tools that may not be available with your initial 'provider'.

As https://genealogy.stackexchange.com/a/3550/104 says, anyone considering uploading their data to a public DNA database or a DNA utility site such as gedmatch should ensure they are happy with the privacy arrangements first.
Answer: Family Tree DNA has a Transfer Program that allows you to import DNA results from both 23andMe and AncestryDNA. It might be useful to have another company analyze your DNA to see if there is any significant difference in what they say are your ethnic origins. But the greatest value would probably be in having your DNA match against the other Family Tree DNA customers to find potential relatives. DNAeXplained shares some other possible benefits based on additional features that Family Tree DNA offers for genealogists.
Public DNA databases allow you to upload your DNA data to search for matches. Though be aware of some privacy concerns when making your DNA results public.
Answer: Family Tree DNA allows you to join specific groups for DNA comparisons.  In joining a family surname group, you may find other submissions that closely match your submission. You can contact close matches via the FT database, and in corresponding with a match you may find out how you are related or find and unknown relative who has your family line identified back further than you do.  When you contact them, you are not given their email address, if they want to respond to you it is up to them.  Same for you. Joining a haplo-group that matches yours may tell you where your family originated even if you can't find the links between.
Answer: Here's one use of exported raw data from Ancestry.com.
I just used my data from Ancestry.com to compare the results to various interesting rsIDs related to health, appearance, etc. using Promethease:
http://www.snpedia.com/index.php/Promethease
There's a $5 online version, $2 offline (Mac or Windows, takes about 10 minutes to run), or free offline (same program slowed down to 4 hours).
The offline version means that while it downloads an updated database of interesting SNPs, it does not upload yours back to anywhere, all of the comparison happens on your own computer.
While it's not a diagnosis tool, seeing how my genes stack up to current research into risk factors for various diseases is very interesting and well worth the few button clicks it took to get it from Ancestry.
Answer: If you have a cousin your curious to verify whether they COULD BE a direct maternal or paternal cousin, then you can play snap, with the corresponding mtDNA and YDNA value sets. If a direct cousin the corresponding mtDNA or YDNA sets should be identical, ignoring no calls, and any formatting tweaks between providers.

Why would I export my raw DNA data?


SXA Search box - add SXA token support to Rendering parameter for SearchPageResults

Question: We have an SXA Search box defined on a partial design in our Master Shared site. The problem is we need to have the SearchPageResults rendering parameter field use a query to pull the search results page relevant to the derived host site, but it seems that setting the SearchPageResults to a query value such as query:$home/search-results doesn't work. It doesn't resolve to the proper search results page when viewed from a derived site with the the search-results page existing in that specific place.
I've done some reading; I don't believe rendering parameters support Sitecore queries syntax with SXA tokens, or at least the SXA components don't from what I can tell. I was talking to some team members and they suggested I could set up the SXA Token pipelines to handle the Rendering Parameters for the component.
However, Googling and digging through Sitecore documentation has only gotten me so far. I would think the following configuration would work for what I'm trying to do:
<code>    <pipelines>
      <getLookupSourceItems>
        <processor type="Sitecore.XA.Foundation.Multisite.Pipelines.ResolveTokens.ResolveMultisiteTokens, Sitecore.XA.Foundation.Multisite" resolve="true"/>
        <processor type="Sitecore.XA.Foundation.Presentation.Pipelines.ResolveTokens.ResolvePresentationTokens, Sitecore.XA.Foundation.Presentation" resolve="true" />
        <processor type="Sitecore.XA.Foundation.Theming.Pipelines.ResolveTokens.ResolveThemingTokens, Sitecore.XA.Foundation.Theming" resolve="true" />
        <processor type="Sitecore.XA.Foundation.TokenResolution.Pipelines.ResolveTokens.CurrentTemplateToken, Sitecore.XA.Foundation.TokenResolution" resolve="true" />
        <processor type="Sitecore.XA.Foundation.TokenResolution.Pipelines.ResolveTokens.EscapeQueryTokens, Sitecore.XA.Foundation.TokenResolution" resolve="true" />
      </getLookupSourceItems>
    </pipelines>
</code>
Any ideas on how I can get this to work? Am I on the right track? Perhaps there's a simpler way of accomplishing this that I'm not seeing.
UPDATE -
Looking at a note on the ticket, I see I may have left out some details. Let me try again.
I have my search box inside a partial design that is located in my shared site "Master". The search box component has a Rendering Parameter named SearchResultsPage, which points to the search results page it should redirect it's query to. I tried to pass the parameter "$home/search-results", which is where the page will be on every derived site of "Master", such as my derived site "QA."
The problem is, when I set this value on the partial design in "Master", it doesn't work on my derived site "QA". I'm not redirected to my relative search results page path from the QA site, I'm just taken to the same page with the fields relevant to the query updated past the hash. It would seem the relative path I set in the "Master" partial design isn't being resolved properly on the child "QA" site.
Note: the search-results page doesn't exist on "Master", so I don't expect this to work in the context of working with the "Master" site itself, such as editing the partial design in the "Master" site in Experience Editor. The issue I'm having is it's not resolving on my derived "QA" site.
Let me know if anything here isn't clear.
Comment: Sounds like you are not setting up the Scope Query properly. This scope is converted to a search that automatically scopes the results to the site.
Comment: @MichaelWest see the UPDATE section for further details. I don't believe it's the search scope that's the problem, it's that I can't seem to use a relative path with SXA tokens in a Rendering Parameter to have go to the proper search results page.
Answer: The solution I went with is outlined in the answer here, with some changes made on our end.
Displaying SXA Search Results on the separate page


A list of parts of speech

Question: I want to know if there are other parts of speech -other than particles- in other languages than English or other Romance/Germanic languages.
Comment: Different linguists analyse language in different ways which makes this too broad.
Comment: Good question, though I wouldn't count particles and inflections as parts of speech.  We have perhaps verb, noun, adjective, preposition/postposition, and then what?
Comment: English also has adverbs, at least :) And I love romantic languages.
Comment: [The 'Part of speech' WP page lists](https://en.wikipedia.org/wiki/Part_of_speech) some parts of speech under the section 'functional classification'.
Comment: @IvanKapitonov's answer is quite romantic, but, more explicitly, the usual name is: romance languages.
Comment: Why are you separating "romantic/germanic" from Indo-European? Our names for the parts of speech go back to the ancient Greek grammarians.
Comment: @GAMPUB thank you :) I should've put "romantic" in quotes indeed. Or even better edited the question.
Comment: @fdb I didn't know the extent to which the parts of speech go back to.
Comment: The terms for the parts of speech or better the word classes are Latin, not Greek. But the Romans  learnt from the Greeks and translated the Greek terms into their language.
Answer: The problem with this question is that parts of speech are just a construct used for the description of language - not necessarily a real thing in a language. You can see that across languages only nouns and verbs are fairly uncontroversially universal with adjectives being another good but still disputed candidate (See Dixon's Basic Linguistic Theory).
So if you were starting with a different language you might be surprised by things like determiners in the languages you list or prepositions. Other languages may have various classifiers that may seem a bit strange. There are other things that represent a distinct category but do not make it as a part of speech like quantifiers. Even in English, you will find lists ranging between 8 and 11 different parts of speech depending on the authors' perspective and need.
You will also find a lot of variations in the internal typology of parts of speech across languages. So Czech pronouns and English pronouns or adjectives will come out looking quite different (e.g. Czech possessive adjectives).
Answer: The most important message is that about one dozen parts of speech seem to be sufficient for part-of-speech (POS) tagging. Additional markers often include things not classically regarded as parts of speech, such as punctuation, symbols (e.g., for Twitter corpora!) and a "residual" container class for everything else.
There is some disagreement about the content of some classes: Traditionally, pronouns include pronomial adverbs and adjectives. A modern school takes the pronomial adjectives out of the pronoun class and names them determiners (and often, the classical articles are put there, too) and classifies the pronomial adverbs (e.g., "how") just as adverbs.
There are several attempts to unify POS over languages, and here are some them:
EAGLES: http://www.ilc.cnr.it/EAGLES96/pub/eagles/corpora/annotate.ps.gz EAGLES Recommendations for the morphosyntactic annotation of corpora, ''Obligatory attributes/values, Major Categories'', §4.2.1 on page 7
OXFORD: http://www.natcorp.ox.ac.uk/docs/URG/codes.html#klettpos Simplified Wordclass Tags
STTS/HW: http://www.sfs.uni-tuebingen.de/resources/stts-1999.pdf Guidelines für das Tagging deutscher Textcorpora mit STTS (Kleines und großes Tagset), ''Hauptwortarten'', Tabelle 2.1 on page 4
TANL: http://medialab.di.unipi.it/wiki/Tanl_POS_Tagset#Coarse-grained_tags Tanl Coarse Grained Tags
UD-17: http://universaldependencies.github.io/docs/u/pos/all.html Universal Dependencies
UP-12: http://www.petrovi.de/data/universal.pdf Universal POS 2nd paragraph in the right hand column of page 2
The summary table below shows the tags drawn from the tag sets quoted above (in their original spelling).
<code>||= EAGLES =||= OXFORD =||= STTS/HW =||= TANL=||= UP-12 =||= UD-17 =||= Notes =||
||  N       ||  SUBST   ||  N        ||  S    ||  NOUN   ||  NOUN   || noun    ||
||          ||          ||           ||       ||         ||  PROPN  || proper noun/named entity ||
||  V       ||  VERB    ||  V        ||  V    ||  VERB   ||  VERB   || verb    ||
||          ||          ||           ||       ||         ||  AUX    || auxiliary verb (includes modal auxiliaries like ''should'' or ''must'') ||
||  AJ      ||  ADJ     ||  ADJ      ||  A    ||  ADJ    ||  ADJ    || adjective ||
||  PD      ||  PRON    ||  P        ||       ||         ||         || pronoun/determiner (as one single class) ||
||  AT      ||  ART     ||  ART      ||  R    ||         ||         || article ||
||          ||          ||           ||  D    ||  DET    ||  DET    || determiner ||
||          ||          ||           ||  T    ||         ||         || predeterminer (e.g., '''tutto''' il giorno)
||          ||          ||           ||  P    ||  PRON   ||  PRON   || pronoun ||
||  AV      ||  ADV     ||  ADV      ||  B    ||  ADV    ||  ADV    || adverb ||
||  AP      ||  PREP    ||  AP       ||  E    ||  ADP    ||  ADP    || adposition (circum-, pre-, postposition) ||
||  C       ||  CONJ    ||  KO       ||  C    ||  CONJ   ||  CONJ   || conjunction ||
||          ||          ||           ||       ||         ||  SCONJ  || subordinating conjunction ||
||  NU      ||          ||  CARD     ||  N    ||  NUM    ||  NUM    || numeral; cardinal numeral (ordinals are tagged as adjectives or adverbs) ||
||  I       ||  INTERJ  ||  ITJ      ||  I    ||         ||  INTJ   || interjection ||
||  U       ||          ||  PTK      ||       ||  PRT    ||  PART   || unique; particle ||
||  R       ||  UNC     ||           ||  X    ||  X      ||  X      || residual; unclassified; other ||
||          ||          ||           ||       ||         ||  SYM    || symbol ($, %, §, ©, +, −, , !http://example.org, !email@example.com) ||
||  PU      ||  STOP    ||           ||  F    ||  .      ||  PUNCT  || punctuation ||
||  13      ||  11      ||  11       ||  14   ||  12     ||  17     || total number of tags ||
</code>
STTS/HW lacks generic tags for punctuation and other: They could be supplemented as $ (for punctuation) and X (for other)
UP-12 lacks a tag for interjection; interjections are mapped to the class X
UP-12 and UD-17 lack a tag for article, it is absorbed into the determiner class.
TANL lacks the category particle, the Italian negation particle ''non'' is classified as an adverb.
TANL considers article, determiner, predeterminer, and pronoun as first-class citizens in parts-of-speech.
OXFORD classifies cardinal numbers as adjectives.
Comment: re:   OXFORD:   Cardinal numbers as adjectives?   I can't find the adjective in "2 and 2 make 4."
Comment: This is how they treat them. The CLAWS5 tag "CRD" is mapped to "ADJ" as seen in the linked documentation.
Comment: These sets were not developed to do the same things as (for instance) generative or traditional grammars were sposta do. Consequently they don't preserve the same properties as they do
Answer: After a quick scan of the paper A Common Parts-of-Speech Tagset Framework for Indian Languages, nothing stood out as particularly distinct from the POS of European languages. However, on running over a chapter from Antony's thesis on Kannada, I noticed two categories I have not seen in most European languages: echo words, and reduplication. Finnish and Hungarian seem to have these two categories of words.
On second thought, English seems to have echo words too (teensy-weensy, itty-bitty, higgledy-piggledy, etc.) but I have not come across POS tag sets that recognize these as a separate category, probably because there are just a handful of such expressions in English. In contrast, in Indian languages, these POS categories are open classes.
Comment: I would consider  "echo words" as a type of word formation, but not as a word class (part of speech). I don't know what reduplication is in Finnish,  but in Latin  it is a rare way of forming the perfect stem of irregular verbs  as in curr-ere to run,  perfect cu-curr-i  I have run. That has nothing to do with word class. The word class of cucurri is verb.
Comment: Could I add that English has one verb whose past tense is formed by reduplication: Do/did.  The second 'd' isn't the weak-verb suffix, but an echo of the first.
Comment: @rogermue You first sentence applies just fine to English, but not to Indian languages, as explained in my second paragraph. In Indian languages, [Echo words](https://en.wikipedia.org/wiki/Echo_word) modify the semantics in a manner quite different from my English examples. While the word class of the resultant phrase is the same as the root word (be it noun, verb, adjective or adverb), what would you say is the word class of the echo word? Keep in mind that the echo word cannot be used in isolation.
Comment: @DavidGarner  Even if  "did" is seen historically as a verb form with reduplication, this is not a word class, did is a verb form.
Comment: @prash  I've read what Wikipedia says about echo words in Tamil. A special word form that can be added after a noun with the meaning "and similar things". I doubt that such words (the form depends on the form of the noun) that only have one meaning form a word class. Its more an idiom-like thing. I doubt that anyone would say that "and the like"  is a word class, even if that expression changes its form according the preceding noun.
Comment: @rogermue Wikipedia lists only nouns, but echoing can be done just as readily with verbs, adjectives, and adverbs. As for 'I doubt that anyone would say that "and the like" is a word class', the thesis chapter I linked to clearly disputes that. If you can dismiss it by calling it an "idiom-like thing", why not use that approach with **all** grammar? Please remember that these echo words are not random. Their formation is entirely rule-driven, and the semantics, quite rigid.
Comment: Sorry, @rogermue, I didn't mean to suggest that it was a word class; I was just pointing out that there's a relic of IE reduplication in English.
Answer: English has: noun, pronoun, adjective, verb, adverb, preposition, conjunction, interjection, particle (yes, no, to), article.
English has several forms of verb that can be considered parts of speech depending on viewpoint: present participle, past participle, gerund.
Russian does not have articles, but has participle and transgressive. Both described as a form of a verb in English Wikipedia (English also has participles), but in Russian linguistics they are considered separate parts of speech.
German language has another form of verb, known as "inflective". This can also be viewed as a separate part of speech depending on viewpoint. In Russian such words are considered interjections.
Some languages (including English and Latin) have clitics, which are sometimes classified as parts of speech, but I prefer to count them as parts or word (morphemes) that come after ending (prefix(es)-root-suffix(es)-ending-clitic). In Russian clitics (-де) are classified as particles.
Comment: ... and numerals?

A list of parts of speech


Placing a Police Officer Under Citizen's Arrest

Question: If you place a police officer under citizen's arrest, does that officer still hold the authority to arrest you?
Answer: While it is from a different jurisdiction, the following goes to the heart of the matter:

Arrest, when used in its ordinary and natural sense, means the apprehension of a person or the deprivation of a person's liberty. The question whether the person is under arrest or not depends not on the legality of the arrest, but on whether the person has been deprived of personal liberty of movement.

Directorate of Enforcement v Deepak Mahajan, (1994) 3 SCC 440 at ¶46 (SC of India)
In your example, the police officer has been deprived of "personal liberty of movement"; if they can still speak there would be no legal impediment to them placing the person who arrested them also under arrest.
It would then be incumbent on both parties to deliver each other into lawful custody. The citizen would need to seek out a law enforcement officer to do this; the police officer has already done so, being their own law enforcement officer.
After this, comes the paperwork.
Comment: In other words, it sounds like "might makes right" until somebody with more authority (or more might) says otherwise?  I.e., the more determined party is going to drag the other before a court, and the judge will decide for both who will be held and for what.
Comment: @feetwet Many states say that someone who has been subject to citizens arrest must be immediately delivered to the custody of an LEO, or an LEO must be called to take custody. Commonly, that LEO can then release the arrestee, since citizens get things wrong from time to time. Of course, if you try disarming a cop, they *will* resist and call for backup, so you're already going to be swarmed with other cops anyways (assuming you even manage to get them actually arrested, which is nontrivial).
Comment: @feetwet Not a judge, a law enforcement officer - anyone can arrest anyone - to be legally detained they must be placed in the custody of a policeman, FBI agent, Military Police etc. whoever has the legal authority of detention. That person can then decide if charges will be laid or the arrestee will be released.
Comment: Could you elaborate on that?  All roads must go through a law enforcement officer?  Even if one fears that those immediately available would be less-than-perfectly-objective in such a scenario?  So if one manages to arrest a police officer, who promptly declares the arresting citizen to be "under arrest," the citizen would be guilty of a crime if he *detained* the cop until he could be delivered to a court marshal or some law enforcement officer of an independent agency?
Comment: Yeah, sounds like in the best scenario this wouldn't play out especially well for the non-LEO citizen.  I wonder if there are any real-world examples?


What is the temperature of outerspace?

Question: I want to know whether the temperature in Outer space is higher than earth's or cold.Is the temperature in outer space vary as it does on earth?
Answer: The temperature in the heliosphere is about one million Kelvin, lower (but still very hot) in the outer regions of the heliosphere, higher close to the sun.
But the density of the plasma is very low, so you wouldn't feel the heat (except close to the sun).
Within Earth's exosphere, reaching up to 10,000 km, the temperature is lower, roughly 1,000 to 1,500 C.
In interstellar space there exist hot (e.g. 10,000 K) and cold gas clouds.
Due to the very low density, hot and cooler fractions can penetrate each other, such that there doesn't need to be a uniquely defined temperature.
The large-scale average temperature of outer space should be 2.7 K (about -270.5 C), close to the CMB black body temperature.
Comment: You don't differentiate between the day and night sides of Earth's exosphere.
Comment: @called2voyage Temperature fluctuations of the exosphere seem to be dependent of solar activity, not much from diurnal factors, but I've not yet found an explicite reference to be quite shure. This paper investigates some of the waves of the upper atmosphere: http://heliophysics.nasa.gov/SolarMinimum24/papers/BruinsmaForbes_JGR_2010.pdf
Comment: where are you getting the average temperature of outer space? What are the steps taken to get this number?
Comment: @RyanMcGaha From the linked WP article: _The baseline temperature, as set by the background radiation (from the theorized Big Bang), is 2.7 kelvin (K)._
Answer: Than answer to whether it varies or is definitely yes but not in the same way as on Earth. The temperature in completely empty space with no stars for large distances would approach absolute zero ( −459.67°F or −273.15°C depending on the system to which you are accustomed) the further you go away from any heat producing body such as a star or active black hole. If you get close to stars or active black holes or many other things, the temperature could be thousands of degrees higher than on Earth. It just depends on distance.

What is the temperature of outerspace?


How to manipulate speed of playback music during live show?

Question: I'm a sound engineer for the play my school is doing. At one point, which the director has warned me could vary each night, the music that will be playing out of my laptop and into the mixing desk will need to slow down, as the characters take some drugs and it needs to get a bit psychedelic and weird. I don't know, however, how best to manipulate this speed change? The only idea I've have is to  use my budget to buy a digital DJ deck/turntable which has a speed control on it and run the music through that. If that's the best option, can anyone recommend a turntable?
Answer: Since you're working with an audio file, not "live" sound...and you appear to be trying to do this with no budget...you can download Audacity (free open source program) and do time manipulation to the file within it. Work with the director to get the desired effect, then output the file. You'll have something predictable and repeatable for the performers that way.
This video should give you most of the info you need to pull it off:
Answer: If it were me, I would prepare a separate audio file for the slow motion cue, and make sure that the regular speed cue before it is considerably longer than it needs to be. And then trigger the crossfade when the action onstage goes slow motion.
In my experience, that kind of loose instruction from a director often just means, "I don't know exactly when yet.  This is hard for a sound designer to plan around! But if you are manipulating the slowdown on the fly, it will (likely) be completely different every performance. In some cases, this is the desired effect, and the director and actors like the spontaneity. Again, in my experience, actors like some predictability from the music. Music can then be a familiar guide to lead them through the story.
Just my thought.
If the music is going hyper slow, like Paul Stretch slow, then it won't matter too much if it triggers at EXACTLY the same part of the music pre-slow down.
Comment: Turns out, you were entirely right. I sat down with the director, and managed to get it out of him that he does want it at the same spot every night (he's a nightmare). So thanks for your advice, but I'm going to mark Shaun Farley's answer as correct because I'm going to use Audacity. Thanks!
Comment: Great! Glad if I was of some help.
Comment: If you want ridiculous slow, check this out: http://hypermammut.sourceforge.net/paulstretch/
Answer: You could just run the entire mix from a DAW and perform the pitch shift there using a real-time pitch shifter plug-in (there are many ways you could do this in terms of mixing and control). This is probably the most easiest way, given that computers are so commonly used for playback anyways (in addition to decks, which you don't seem to be using).
You may need to try out how it sounds.
Answer: I think a DJ CD or MP3 player software is probably the best but a software sampler might work as well or PrTools can playback at 1/2 speed(shift-play?), other software might do the same.  With the DJ software you could vary the sound more and it would be much smoother I think.
Answer: You can use the 'Rate' fader in Reaper for on-the-fly rate changes.  Using a MIDI or OSC fader may help to smooth it out and reduce pops (not sure), but in any case you can type in a new value and press Enter on the cue.
The Rate parameter can be found just next to the transport.  You can try Reaper for free, if you don't have it.
http://www.reaper.fm


Calculate current drain from the battery in a drive

Question: Control module voltage is one of the OBD PID. It signifies the car battery voltage. Is there any way to calculate how much current is drawn in a drive (say 7 km from my office to home). The voltage will keep on decreasing, increasing in this drive, but I am interested to calculate how my current (or rate of current) is being drawn during discharging of the car battery. The calculation would involve using OBD PIDs (most preferably the generic Mode 01 PIDs).
Comment: I don't think any production car does this with generic obd2 PIDs and the only manufacturers I know that do measure battery current draw are on GMs and Hondas.
Answer: The notion that battery voltage will reduce while driving is incorrect.
All modern production vehicles will boast alternator acting as a electrical generator to maintain battery voltage. The battery cannot sustain sufficient charge for even an hour in the absence of a charging issue.
As such, control module voltage will remain steady during normal operation and cannot be used to perform any kind of electrical energy consumption calculation.
Comment: Yeah, sorry my bad. I meant how will I come to know if my battery is draining faster compared to normal rate while doing operations during driving like listening to the radio, giving indicator lights etc.
Comment: You can't because the battery is charging while the engine is running. Plus, the OBD-II PID's do not provide you the necessary information. It's like someone trying to assess the condition of a mobile phone 's battery while it is being charged.
Answer: On some vehicles you can monitor duty cycle on time of the alternator control circuit or alternator load. Both are usually an on/off signal that will give you a percentage. Some flaws in this are something like A/C on will cause 100%  whether needed or not and hard acceleration ( like going uphill ) the car will disable the alternator 0% to give you more engine horsepower ( the alternator is a load on the engine ).


PhD Thesis based on published articles on different topics

Question: I am in 3rd year of PhD and I was suppose to graduate after 1 year, but suddenly due to some unknown reason my adviser gave me 2 months to write my PhD dissertation. He said I have published 7 SCI journals (as a first author) and what I need to do is just compile all articles into single document.
I know it is common to publish article based on PhD dissertation.  Is it also common to compile a PhD thesis based on published SCI journal Articles? More tricky part is that out of 7 only 2 articles are written on same topic rest of work is totally different. But he insist I can create a link between all articles, which in my opinion doesn't make any sense. It something like saying apple and orange are same fruit.Let say I have no other option except compile my dissertation within 2 months. Is it possible that the PhD dissertation chapters may cover unrelated topics? Let say one part is related to Operating System and other part is related to Future Internet?
Comment: So-called "stapler theses" are quite common. Surely the articles are not that different, as you worked on all of them. You need to think of some unifying theme to join them together, even if it is a bit forced. And, you don't need to include all 7 papers if that makes it easier to join them.
Comment: A PhD merely shows that you are qualified to conduct research. So, finishing it quickly has advantages. E.g., promotion. Ask your supervisor if there's any reason to finish early. Perhaps he has an agenda that's mutually beneficial (e.g., promotion).
Comment: And, the 'stapler thesis' is a real thing - I have several from various colleagues on my shelf. They really are reprints from journal articles stapled between two cover sheets with the thesis title on the front. They all seem to be Scandinavian in origin, so your mileage may vary.
Comment: Thank you all for the comments and answer. Seems like there is no particular agenda and I feel maybe it's a kind of funding issue. I am trying to take it positively but feel uncomfortable to see I have a week PhD dissertation. I had some ideas plans for my dissertations which now I might publish in Journal in coming future.
Answer: First of all, writing a PhD dissertation in 2 months is one hell of a task. You should probably talk to your supervisor about more time.
I believe it is not uncommon, as Thomas stated in the comments, that people assemble a PhD disseration from the publications they had during their time. Many people work of different topics at the same time, but usually there is something that combines them. The title of your dissertation can be very vague and cover a wide topic. In your dissertation you can split it into different chapters of sections according to your covered topics. Of course, it is good if you find a common thread and can build upon that. Even if you don't, I still think it is okay. After all, that seems to be what your supervisor wants.
If you are really unsure, there is no way around talking to your supervisor about it. Ask for his expectations and tell him about your plans. Then, you will be able to meet somewhere in the middle.


web3 deprecated - web3/ethjs etc. difference

Question: I am currently working with smart contracts and the implementation and communication to web apps using MetaMask. I am now confused about what to use and how to implement it. What exactly will be deprecated? What and how should I use it now? Can you tell me an actual and not deprecated way/tutorial to connect to MetaMask, ask for balances and connect to contracts etc.?
Comment: What do you exactly mean with "web3 deprecated"?
Comment: "MetaMask: web3 will be deprecated in the near future in favor of the ethereumProvider
https://github.com/MetaMask/faq/blob/master/detecting_metamask.md#web3-deprecation" I get that in the console.
Answer: Web3 will not be deprecated,
I am not totally sure but as i understood this post :
https://github.com/MetaMask/faq/blob/master/detecting_metamask.md#deprecation-of-global-web3js
MetaMask and mist will stop injecting a web3 global object as they do right now because it is chainging fast and a lot. they will instead inject an other API which is smaller and can let the users use a locally injected ( imported via code ) version of web3 or any other provider instead.
So you will be importing web3 for example  :
var web3 = require("web3");
then you will integrating it with MetaMask by initializing the provider by the given provider (the Ethereum Provider) : web3.setProvider(web3.currentProvider)
Please correct me if i am wrong.
Answer: Well smart contracts use events to communicate with the frontend. But, I suggest you start with the basics so learn how to call metamask using a button :
https://github.com/MetaMask/TipButton/blob/master/index.html
Then, you can learn how to use Remix to deploy your smart contract and play with it a bit :
https://remix.ethereum.org/
and finally you can try this tutorial :
https://coursetro.com/courses/20/Developing-Ethereum-Smart-Contracts-for-Beginners
I hope this would help a bit.
Best,
Tarik


Can this function be expressed in terms of other well-known functions?

Question: Consider the function $$f(a) = \int^1_0 \frac {t-1}{t^a-1}dt$$
Can this function be expressed in terms of 'well-known' functions for integer values of $a$? I know that it can be relatively simply evaluated for specific values of $a$ as long as they are integers or simple fractions, but I am looking for a more general formula. I have found that it is quite easy to evaluate for some fractions--from plugging values into Wolfram I am fairly sure that
$$f(1/n)=\sum^n_{k=1}\frac{n}{2n-k}$$
for all positive integer $n$. However, $f(a)$ gets quite complicated fairly quickly as you plug in increasing integer values of $a$, and I am stumped. Do any of you guys know if this function has a relation to any other special (or not-so-special) functions?
Answer: Notice that

$$ \int^1_0 \frac {t-1}{t^a-1}dt= -\sum_{k=0}^{\infty}\int_{0}^{1} (t-1)t^{ka}dt = -\sum_{k=0}^{\infty}\frac{1}{(ka+1)(ka+2)}. $$

Now, if you sum the above series with help of maple or mathematica you get the same answer as in Jonathan's answer

$$ f(a)=\frac{1}{a}\Big(\psi\left(\tfrac{2}{a}\right)-\psi\left(\tfrac{1}{a}\right)\Big), $$

where $\psi(x)$ is the digamma function.
Answer: Mathematica says that
$$f(a)=\frac{1}{a}\Big(\psi\left(\tfrac{2}{a}\right)-\psi\left(\tfrac{1}{a}\right)\Big)$$
where
$$\psi(z)=\frac{\Gamma'(z)}{\Gamma(z)}$$
is the digamma function.
Answer: Let $\zeta$ be a primitive $a$-th root of unity. You can use a partial fractions expansion to rewrite
$$
\frac{t-1}{t^a - 1}
= \sum_{i=0}^{a-1} \frac{\zeta^i - 1}{a \zeta^{i(a-1)} - 1} \frac{1}{t - \zeta^i} $$
and then integrate termwise. The result doesn't appear to simplify nicely, though.


"unknown file system. Grub rescue" won't let me access to BIOS

Question: So I installed Ubutu 13.04 alongside Windows 8 and after a week or so it stopped working and I couldn't figure out how to recover. I went back to windows for a little while and downloaded Ubuntu 12.04 to install that version. As I couldn't access the partition I had made for Ubuntu, I formatted it and then made a bootable USB with the iso. I went to bios to change the boot settings from UEFI and when I applied the changes it showed me "Unknown filesystem. Grub rescue" and won't let me Access to bios to go back to Windows and try to figure something out. Any help is much appreciated.
Answer: You need Windows 8 Recovery CD, you can make one by using specific option on Windows 8 or by downloading image of it (search google for guides). Then, make a bootable CD or USB (I recommend using WinToBootic) and repair boot - automatically or in command prompt (two commands: bootrec.exe /fixboot and bootrec.exe /fixmbr).


How can I remove thousands of spam members on a non-member site?

Question: My first EE 1.6.8 site is coming back to haunt me. The site crashed and burned the other day. Took a look at the members in the DB and there's about 78000 spam members in there. I have access to PHPAdmin for the DB, but I don't know what I'm doing in there. Any help?
Answer: Always backup first!
Hopefully they're all still pending. Go into phpMyAdmin query tab and run the following query to delete pending members:
DELETE FROM exp_members WHERE group_id = 'PENDING GROUP ID'

You can also run the query right from the control panel:

Admin › Utilities › SQL Manager › Database Query Form

If the site isn't setup to verify membership, you could run a query to delete all members after a certain date, specifically the day of spam and after:
DELETE FROM exp_members WHERE join_date > 'UNIXTIMESTAMP'

Use this tool to help figure out the unix timestamp. If you don't feel comfortable running the query at first, you could always run a SELECT query to confirm correct selection of members.
SELECT * FROM exp_members WHERE join_date > 'UNIXTIMESTAMP'

Comment: Thanks Siebird! I ran the query on exp_members for group_id that all the spam registrations had. I also ran queries for a couple other things and it was a success. Thanks for pointing me in the right direction, I didn't have any previous experience running db queries.
Comment: Awesome, glad you got it sorted!


Sent ETC from hardware wallet to ETH address on poloniex

Question: I mistakenly sent ETC from my hardware wallet to an ETH address on poloniex. I sent an email to Poloniex helpdesk and they sent me over here to resolve the issue. I've read online that people have made similar mistakes as me and have been able to recover there coins.
Here is my response from Poloniex.
Answer: It actually appears that you may have emailed the Ethereum Foundation instead of Poloniex; Hudson Jameson is part of the Ethereum Foundation and not Poloniex.
Log into Poloniex's customer support portal here and provide them with your tx id, as you did above. Let them know what happened.
Poloniex controls the private keys and, therefore, should be able credit your account the ETC to the amount that was sent to your ETH deposit address.
Comment: You are correct. I forgot that I had sent emails to both Poloniex and Ethereum Foundation and I assumed the email was from Poloniex. Poloniex got back to me and they were able to credit me with my etc.


How to calculate variance between baseline 1 start and actual start in MS Project (2007)?

Question: I would like to find out the variance between baseline start 1 and actual start. However, I realised that the start variance value as seen from the Variance table actually shows the difference between the baseline and actual start. How should I go about getting this value? Thanks!
Answer: In "Options", find the EV calculation choice and choose Baseline 1 for your EV calculations.  I don't have 2007 anymore so I can't direct you more specifically.  But the EV Calculation method is where you need to make the change from baseline to baseline 1.
Answer: Another way to approach this is to save your old schedule as Baseline1, then do your schedule modifications and rebaseline as Baseline. I've found this to be a bit easier to remember to do compared to changing the EVM options.


I want to move drivers out of my archive manager/file roller

Question: I want to move drivers that are in my archive manager/ file roller to Update manager, ubuntu software center or synaptic package manager
Answer: Update manager, Software center and Synaptic all only access software present in one of the package repositories you've added to your system.
There is no easy way to have them use a archive file from the archive manager (you'd need to convert the driver archive to a .deb file and set up your own package repository for that).
For some drivers there are already (unofficial) package repositories, so if you tell us which driver you want to add maybe someone knows a repository for it.
Comment: Thanks for the response the driver is= driver-x86_32-4.4.0.tar.gz For a matrox g400, thanks


How might the cooling of the Earth's core be accelerated?

Question: Essentially, what would be the most efficient way of causing the Earth's core to cool as much as possible without damaging human civilization in any other way (the outcome can damage it, but not the process), given our current understanding of physics? Assume financial and political obstacles are not an issue.
Comment: large scale [geothermal](https://en.wikipedia.org/wiki/Geothermal_energy)
Comment: Is there a worldbuilding context to this ?  It sounds off topic at present - science wild idea rather than significant element in world building.
Comment: Not too many ways. The *most efficient* is @nzaman's. Even so, the core is well insulated by a *lot* of rock, and the heat is produced by radioactive decay on a scale that can't reasonably be interfered with given current or foreseeable technology.
Comment: @StephenG - I think its on topic... i.e. a world where people are dealing with this, the process of it happening in the first place might well be relevant - even if just for describing the background of the story.
Comment: How much do you want to accelerate it (at least)? You might want as much acceleration as possible, but can you give a broad rate you are aiming for? I think this is absolutely needed because it makes a difference if you want it cold by December or in 3 billion years. Btw, you always have to assume finite resources, otherwise you can end up with pretty stupid scenarios (just a mandatory comment, it's not as bad here, but your question might be strictly better without that addition)
Answer: I suspect that cooling the Earth's core significantly without destroying civilization may not be possible.
Roughly speaking, the core (inner and outer) is about half the mass of the planet (so 3x10^24kg).  Assuming a specific heat capacity of 500J/kg, and a temperature change of 1000K, that gives us:
500x1000x3x10^24J = 1.5x10^30 Joules to get rid of. That's a lot.
The oceans weigh about 1.4*10^21Kg, anf would therefore require roughly
4200x100x1.4x10^21J =6x10^26J to raise to boiling point.
So you are dealing with an amount of energy sufficient to raise the oceans to boiling point about 2000 times over. Doing it once would be catastrophic for life on the planet, obviously.
So, no matter how you get the heat out of the Earth - and I can't think of any even semi-plausible mechanisms to do so* - the chances are that you'd destroy everything on the surface by doing so. Even dumping the heat near to the Earth would probably cause overheating by radiation.
*Physical possibilities:

Conduction: Put many, many rods of come highly conductive material all the way to the core. Except that mantle convection would quickly shear them apart, and any density contrast with the mantle would cause them to collapse.
Convection: Stir the mantle more vigorously to allow more cooling? Would disintegrate the crust and everyone on it.
Radiation : Expose the core directly to space by digging a very big hole (not physically plausible).  Place a black hole at the Earth's core, and somehow stop it swallowing matter, just radiation. Would work, but probably destroy the planet, again.
Comment: You should also mention that *successfully* cooling the core would make it contract with "amusing" effects to people on top of the sphere around it and that it would shut down the planets magnetic field with equally "amusing" effects to any civilizations relying on electronics and radio communications.
Comment: Yes.. I sort-of assumed that the whole idea behind quietly cooling the core was to shut down the magnetic field.. but yes, if every plate boundary became a site of rapid convergence at the same time it wouldn't be fun.
Comment: Now that you mention it, I cannot think of any other reason for cooling the core myself.
Answer: Utterly insane method: nested heat pumps.
Use a geothermal heat pump to power another geothermal heat pump, which is used to directly cool the core, or whatever depth of the mantle you can reach. Localised cooling and compression would crush the pipes within weeks, if not days, but with large enough pumps (and enough pumps), you could probably set off some major earthquakes on the surface.
Of course, that leaves the issue of what to do with all that waste heat...


Royalty free, Open Source Data

Question: Does anyone know of a site that lists various open source data feeds or data stores?  By this I do not mean OS database applications like MySQL or Postgre, but royalty free sources of DATA.  For example, IMDB.com allows you to download their data for free, but it is proprietary and cannot be used for commercial purposes for less than $10k.  It would be nice if there was a royalty free version of that somewhere.  However I'm looking for any source of data in any industry--entertainment, auto, tech, etc.
Answer: Freebase has structured data on approximately 20 million topics or entities.
http://wiki.freebase.com/wiki/What_is_Freebase%3F
http://en.wikipedia.org/wiki/Freebase_%28database%29
Answer: Freebase is a great option as Osvaldo mentioned, some others that look interesting (haven't personally tested them but have browsed / heard mention of):
http://opendata.socrata.com/
http://www.infochimps.com/search?query=&view=list&price_category=free&dataset_type=&has_categories=&order=balanced
Although not a list of useable data sets for free, Some cool data on the federal budget available for the data viz challenge which could be some fun if you're just trying to learn something.  Not so useful if you're trying to build something to sell :)
www.datavizchallenge.org/data - sorry for not hyperlinking these - don't have enough rep to do more than two hyperlinks :)

Royalty free, Open Source Data


Compute Nash Equilibrium for 2-player games

Question: I want to compute a mixed strategy that will be the Nash Equilibrium of the game.
I have used my knowledge in order to create the system for the mixed strategy.
I concluded on a system with 3 variables and 5 constrains.I am not able to solve this system using the common Gaussian Elimination method.This system is a linear program from what I can imagine.I have searched google for similar examples but all the examples was on 2-player games with only 2 strategies per player.In those games was quite easy to compute the mixed strategy.I am thinking of using the simplex method for finding the NE but I am thinking that this is weird for such a small game...
Are there simpler method that can be used in computing a NE profile?
Thank you.
Comment: If general linear programs were solvable by some easy method that wasn't the simplex method instead of the simplex method, everybody would be using it. For a 3x3, you might be able to simplify it by inspection (as you are trying to do), but you also might not.
Comment: Did you mean linear program? That's what it sounds like when you say "system with 3 variables and 5 constraints". If it's a zero-sum game, computing the mixed strategy equilibrium is easy, and can be done with the simplex method and linear programming. If it's not a zero-sum game, computing the Nash Equilibrium, is in general hard, but should be possible with such small numbers. You haven't given us enough information to be able to answer your question properly.
Comment: The general question is hard, see for example the following paper and its references: http://arxiv.org/abs/1104.3760. Your problem has very small numbers, so it might be solvable after all, perhaps with more computational effort than what you'd expect.
Comment: @Peter Criss-cross? I always wondered whether it is actually used (and what exactly does it do).
Comment: Yes I have a linear program and I am trying to find a way to calculate the mixed strategy without using the simplex method.I tried to look for dominant strategies to make the problem smaller but I am not able.The game is a 3x3 game but it is not a zero sum game.
Comment: Ok I have found out that we haven't cover this topics on our lectures.I understood that if I can't make my problem smaller (e.g dominant strategies) it is very difficult to find a Nash Equilibrium.It is better if i delete the question?
Comment: You can use the following web-based software to enumerate all equilibria of general bimatrix games, which includes zero-sum games: http://banach.lse.ac.uk/.
Answer: We have developed a user-friendly browser-based system to input and solve 2-player strategic-form and extensive-form games:
http://www.gametheoryexplorer.org/ (GTE)
Currently, we support:

finding all equilibria via polyhedral vertex enumeration (which works on the strategic-form representation, which is converted to in the case of extensive-form games; this uses David Avis' lrs http://cgm.cs.mcgill.ca/~avis/C/lrs.htmlW); and
finding one equilibrium using Lemke's algorithm (which works on the strategic-form representation or on the sequence-form representation for extensive-form games).

You can use lrs separately offline to solve larger bimatrix games.
The GTE project is under active development (supported by the Google Summer of Code in 2011, 2012, and 2014), so please provide feedback and/or let us know if you would like to contribute) at
firstname.lastname@example.com
For a paper that covers the basic theory and a number of methods for enumeration of equilibria, see
D. Avis, G. Rosenberg, R. Savani , and B. von Stengel (2010).
Enumeration of Nash Equilibria for Two-Player Games.
Economic Theory 42, 9-37.
For a paper that describes GTE and what it can do, see
R. Savani and B. von Stengel (2014).
Game Theory Explorer - Software for the Applied Game Theorist.
Computational Management Science, 29 pages, to appear. arXiv version
Zouzias' answer gives a good description of how to use support enumeration, which works fine for small examples. The methods in the paper above and used in GTE will in general be much quicker than support enumeration for finding extreme equilibria. In addition, GTE will find the complete set of equilibria (which can include convex combinations of extreme equilibria) by finding maximal cliques in a bipartite graph.
Answer: As far as I remember there is a simple exponential time algorithm for computing  a Nash Equilibrium (NE) for 2 player games.

Guess the support of the NE mixed strategy for each player.
Assuming that you know the support, you now have to compute the weights of selecting each pure strategy. This can be written down as a system of linear equations, which can be solved efficiently. More precisely, the system of linear equations encodes the constraints of a mixed strategy being a NE (i.e., each strategy on its support is best response, sums up to one, etc).

This algorithm can be programmed quite easily assuming access to a linear solver.
Comment: To be more specific about the system of linear equations: if $P$ is the *other* player's payoff matrix, then a player's equilibrium action profile is $P_S^{-1} \cdot \langle 1, \dots, 1 \rangle^T$ (normalized) on the chosen support set and $0$ off it (in this equation, $P_S$ denotes the principal submatrix of $P$ gained by keeping only the rows and columns chosen in the support set $S$).  It's also worth mentioning that you may assume that the two players have equal support size.
Comment: Also, that equation might fail if the equilibrium value is $0$ (because $P_S$ will be singular).  You can dodge this problem by adding $1$ to each entry of $P$, which won't change the equilibrium action profiles.


Travel Maps Creation/Integration

Question: We should offer a feature to create, or integrate travel maps (somewhat like TripAdvisor). It will surely allow us to gain more insight into the destinations fellow members have traveled, and can help along with.
Comment: What do you mean by "travel map"? I don't think we should do route-planning but I do think an illustrative map in the side panel with a marker for every place mentioned in the question, answers, and comments would be super smooth. It could also be leveraged into a different use on our profile page I suppose.
Answer: I think there are many sites with such feature already. Our point is a Q&A site, not the Plan-A-Trip site. If user wants to point out some travel plan, he can share the URL to the google maps or something.
Also Plan-A-Trip question are very uncertain, users provides many options, and this is not how I think this site should work.
Answer: What may be interesting would be a "world heat map" indicating for what country/region of the world a given user is active on the forum.
ie. a user who is only active for questions related to Croatia would have all the countries greyed out except Croatia coming up in red.

Travel Maps Creation/Integration


In SQL Server, when should you split your PRIMARY Data FileGroup into secondary data files?

Question: Our database currently only has one FileGroup, PRIMARY, which contains roughly 8GB of data (table rows, indexes, full-text catalog).
When is a good time to split this into secondary data files?  What are some criteria that I should be aware of?
Answer: There's two parts to this question: when to add a new FILEGROUP, and when to add a new FILE in a filegroup.  First let's talk theory:
Mark's right about the primary reason being performance.
The secondary reason is disaster recovery.  With SQL Server 2005 and newer, you can do filegroup restores.  When disaster strikes, you can restore just your primary filegroup first and bring the database partially online for queries.  Users can run queries while you're restoring other filegroups.  This is useful for databases with a large amount of historical data that may not be required right away, or data warehouses that need to load data into current tables without needing historical data for access.
Another reason is the read/write profile of groups of data.  If you have some data that is constantly written to, and other data that gets heavy read activity, you can build different types of storage to accommodate those needs.  You could put the heavy-write stuff on raid 10, and leave the read-biased stuff on cheaper raid 5.
Now, let's talk files versus filegroups.  When you place objects in SQL Server, you have to place them at the filegroup level.  You can land a table or an index in a filegroup, but you can't pick a specific file.  So everything we've discussed so far has been about when to add a filegroup - but when do you add a file?
If you're designing storage, and you have 80 hard drives, there's a few ways you can break it up:

One pool of 80 drives
Two pools of 40 drives
Four pools of 20 drives, etc...

Different storage subsystems have different performance profiles.  I've worked with some SANs that performed best with 12-16 drive arrays, and anything larger than that didn't have a performance improvement.  Another example is SANs with multipathing: if you have several HBAs connecting your server to your storage, and if your multipathing software isn't real active/active, then you may need one array per path in order to distribute load.  Four paths, four pools of drives will get better performance on those types of drives.
In those cases, you end up with four different arrays, four different drives under Windows (unless you use mount points, and even then it's different folders) and you'll need four separate files in SQL Server.  Those separate files can be in the same filegroup.
Comment: Yup... spot-on analysis of the benefits. The only thing I would add is that you can also frequently off-load indexes from heavily accessed tables to their own spindles/filegroups to boost async/read-ahead performance. I've done that in a few cases with some larger deployments and helped companies save tens of thousands of $$ in hardware costs that their SAN vendors swore they would need to obtain the throughput they wanted.
Answer: The primary reason is performance. When you run out of IOPS capacity on your primary filegroup disk drive, you'll need to expand onto a second filegroup to split IOPS over multiple disks/LUNs depending on storage config.
EDIT:
Brad Wilson made a good comment regarding SSDs. If you're using a composite SSD/SATA/FC storage system, you may want to have different filegroups on different types of storage. You can then put your extreme IOPS requirement tables onto SSD filegropus, while history/stats tables may be stored on cheap SATA filegroups.
Comment: SSDs have a chance to make a HUGE change in the way we think about splitting data, given how much more difficult it is to saturate them because of their ultra-low latency.
Comment: Indeed, good point!
Answer: I would also point out there is a recoverabiltiy / data availability aspect to this question as well. By using multiple file groups, and not placing any user defined objects on the primary file group, you have more flexibility in enabling online restores. this allows piecemeal restore at the file group level.
Online restore are available in Enterprise and Developer editions of sql server later than 2005
Another thought that comes to mind is to separate read only static reference data from transactional data. For larger databases, this could reduce the amount of time and /or space needed to perform a backup.


Sync photos between iPhone and OS X

Question: I want to import photos I made on an iPhone to a MacBook so that I can, firstly, keep a copy on the phone (to be able to quickly show photos to someone), and, secondly, to be able to delete photos from one device and get those photos deleted on the other. In other words, I want the photos synchronised between these devices.
I tried to:

Import photos with iPhoto via cable — it works, but the photos are not synced, just copied;
Enable iCloud Photo Library (Beta) option in Settings — iCloud — Photos on the iPhone. This way all photos get uploaded to iCloud, and I can see them in the icloud.com web-interface, but I can't see them in iPhoto. I tried enabling My Photo Stream and Automatic Import in iPhoto as suggested by Apple docs on their website, but that didn't help — iPhoto still shows "No photos" in iCloud source;
Use Photo Stream (without beta iCloud Photo Library) — still no photos in iPhoto.

I think I may have misunderstood something — in my opinion photo synchronisation should be a somewhat simpler task. I am also quite new to Apple stuff and thus I'm a bit confused with all these different terms; I am more accustomed to simple file operations as on Linux and pre–synchronisation era Windows operating systems.
What would be my options please? For now, I'm more inclined to ditch the whole idea of synchronisation and just copy my photos to the laptop (and maybe delete the sources on the phone).
I am using an iPhone 5s with iOS 8.1.3 and a MacBook Pro Retina mid 2014 with OS X Yosemite 10.10.2.
Comment: Look at Photosync.
Answer: Well, for one iPhoto doesn't have iCloud Photo Library implemented into it. There has been a new update to OS X that adds a new photos app, update your Mac using the Mac App Store ad then also update your iPhone to iOS 8.3 ad enable iCloud Photo Library. Everything will be synced: Edits,  deletes and additions.

Sync photos between iPhone and OS X


IR protocol for Duplo RC Dozer (2949)

Question: Does anyone know where to find the IR protocol for Duplo RC Dozer (2949)? I have the RC Dozer and no remote and wanted to use a universal remote to control it.
Answer: Actually, I have had some success through trial and error and found that a Spybotics remote will do the trick of controlling the RC dozer.

IR protocol for Duplo RC Dozer (2949)


Jenkins Pipeline GitLab API Credentials Management

Question: I have a Jenkins pipeline that executes a build whenever a change is pushed to the appropriate branch. Jenkins uses an API token to authenticate with the GitLab server and checkout the repository. Besides creating a "Jenkins" user account in GitLab and using that user's API token, is there any other way I can manage GitLab authentication for an automated CI/CD pipeline? Each user of Jenkins currently has their own API token.
Answer: Are you doing the building using web hooks or just polling? I think it's inevitable that you'll have to create a Jenkins account to manage API access. This Gitlab link explains how to use the Jenkins Gitlab plugin to manage building when changes are pushed. You'll see they use a Jenkins account as well. This is common practice in my organization to remove single points of failure, such as a departing employee.


Will I be understood in all Portuguese-speaking countries, if I learn Portuguese in Portugal?

Question: I really like the Portuguese language, but if I want to be understood in all Portuguese speaking countries (e.g. Brazil, Cape Verde, Angola, Mozambique), would it be enough to speak "Portuguese" Portuguese? If not, would learning Brazilian Portuguese be a better alternative, given the huge soap opera industry in Brazil.
Comment: May be a little late now, but surely Portuguese Language (http://area51.stackexchange.com/proposals/64172/portuguese-language?referrer=orLJP04NTcWiXPBrvsRSFA2) is a nice proposal for that kind of question. Please commit to it!
Answer: The answer is yes, but you will have to speak a bit slower to most Brazilians,  since they are not so used to listening to Portuguese with "Portuguese accent".
The other way around is easier because Portuguese people are used to listen to Brazilian accent in soap operas.
In Angola, Mozambique, etc. differences also exist but the understanding might be a bit easier due to several cultural and historical reasons.
There are also some minor differences in word spelling and meaning between country's but if you learn Portuguese in any Portuguese speaking country it should be easy to overcome those differences.
There will still be differences in pronunciation and even specific words in each country, specially in colloquial language, but that's the beauty of a language, it's live and dynamic.
There are actually very nice, let's call them, regional terms in each country:

Portuguese / Angola
Portuguese / Brazil
Portuguese / Brazil:  a very nice article, unfortunately in Portuguese, where some  minor grammar explanations and some idiomatic expressions

These are just 2 examples. But I am sure you can find them also for Mozambique, S, Tome and Princepe, Guine Bissau, Cape Verde, India (Goa), Timor and Macau.
Comment: The vast majority of Macau residents don't speak Portuguese at all; the Portuguese language isn't really used outside of law and administration (and the small Eurasian community). You would have a much, much better time trying to speak to people in English.
Comment: @xuq01 I guess that as time goes by that will be less and less spoken in Macau since the territory is now under Chinese administration. But the people speaking portuguese will be understood by other speakers.
Comment: True, the problem here is to find another speaker :-D
Answer: I'm from Brazil. I lived 12 years in Portugal. In Portugal I met many Africans, Portugueses of course and people from countries where speaks Portuguese.
Have many differences between the Portuguese Language ( Brazilian, Angolan, Portugal ). When someone ask me this questions I use to explain the same difference between the English from different countries like USA, UK, Australia. Exist difference but you can communicate.
Normally the Portuguese people will understand better the Brazilian because in television in Portugal have a lot of soap opera from Brazil and news. The Brazilians have less contact with the Portuguese from Portugal but still understandable.
Some words in Portugal are rude in Brazil but are understandable when you are from overseas.
Answer: The Portuguese spoken in Mozambique is a little closer to Portuguese spoken in Portugal. You will be understood here if you are trained in 'classic' Portuguese.
Comment: closer than what? Brazilian? You can write it in full, it would be clearer


In MCU, despite Guardians of the Galaxy and Thor, why aren't aliens actively engaged with Earth society?

Question: Despite Peter Quill being from Earth, despite Asgardians easily travelling to Earth, why is it that it's really only SHIELD that communicates with the aliens? In Guardians of the Galaxy, many different aliens gather together and with Peter Quill being from Earth, we know that the aliens made contact with Earth too. This would logically mean that space travel should be simple for humans too. If space travel is hard for some reason, at least communication with aliens should be pretty normal. But how come Earth is portrayed as an exclusively human society with almost no contact with aliens besides them attacking Earth?
Comment: Have to dispute some premises here. It's not like Peter Quill built a ship and left, he was taken by aliens, so his ability to leave the immediate area has nothing to do with human race capabilities, overall, technologically. As far as his physical ability to do so, he's from Earth, his mother was from Earth, but his father was a nearly omnipotent immortal super-being - that's why he was able to hold the Infinity Stone, and it was the basis of the entire sequel.
Answer: Why aren't aliens actively engaged with Earth society?
Who said they didn't? We do know S.H.I.E.L.D. is working from a long time in secret and covering up the stuff from the rest of the world. Even in Agents of S.H.I.E.L.D. we got to know that they have a

 Alien dead body with them

But I have not seen the show so can't give you much details about it. But as much I am familiar with that show, they do show how S.H.I.E.L.D. cover the tracks of this kind of stuff. So S.H.I.E.L.D. must be keeping humanity away from alien contact.
Also remember Asgardians are also kind of aliens and have been quite involved with Earth.
Despite Peter Quill being from Earth
Does it matter? Is it public knowledge that he is from Earth? He looks like any other Xandarian. And Ravengers only picked him up for Ego, they had no interest in Earth.
Overall in MCU Earth is shown as inferior to other planets and realms based on technology. And the only superior things are kept in secret like S.H.I.E.L.D. or Kamar-Taj.
But how come Earth is portrayed as an exclusively human society with almost no contact with aliens besides them attacking Earth?
Why would they come to Earth as long as they have no profit? Ego did came to Earth for his planning and chitauri for infinity stone etc. Consider yourself, would you go to a nation where you would not get a good job or go to a big nation where you have a better opportunity?
But I can bet in future this will change, Earth has multiple infinity stones now and they are getting technically advance day by day and S.H.I.E.L.D. is also out of closet now.
Comment: I'm not sure I'm remembering entirely correct, but don't some of the aliens Quill encounters claim not to have heard of Earth?
Answer: It's kind of similar to saying "Someone from Ohio moved to California to be an actor. So clearly they can talk to each other, so why aren't there tons of Californians in Ohio all the time?"
So what we know is this:
Some aliens know about Earth. The Asgardians have a long history here, forming the basis of a mythology. Ego visited it on his quest to create a son. There's something about Kree visiting that I can't remember from Agents of SHIELD.
Peter Quill is from Earth, and communicates with aliens. But we know why Peter is with Aliens: The Ravagers picked him up as a job for Ego, but kept and raised him instead. None of those aliens had any particular interest other than Ego's directing them to it.
The Chitari attacked Earth, but it wasn't out of interest from Thanos. It was out of Loki's interest in besting his brother on a planet they know, and where Thor had people he cared for. It was only after the attack was rebuked that Thanos took real interest.
So aside from a long relationship with the Asgardians (where we thought they were gods), the interactions with Earth have just be occasional, one-off incidents.
Why is this?
Maybe there's a Prime Directive style pact among the larger galactic civilization, to not interfere until Humans reach a high enough level.
Maybe because Midgard is one of the 9 Realms ruled by the Asgardians Odin protected it from interference.
Maybe there just never seemed to be anything of value there: Limited technology, limited resources, nothing to learn, not a threat. Maybe Earth is out of the way too.
So
I guess the answer in universe is we don't know, but it seems Earth is not a priority for most aliens aside from the Asgardians (who protect their realms), and the occasional wanderer like Ego who visited hundreds and hundreds of planets.
Out of universe, obviously, it's that we want the world to look like ours despite the crazy things happening elsewhere in the fictional universe.
Answer: With Agents of S.H.I.E.L.D, they introduced Kree which can be classified as aliens... With the Captain Marvel movie, Skrulls are going to be introduced and that might solve why "aliens" are under scrutiny since the events in the movie are "supposed" to occur in the 90s. Hopefully Infinity War is the movie that bridges the gap between interaction with the aliens and humans...


Yosef Bones out of Egypt

Question: What Happened to Yosef Bones when the Took them out of Egypt ot actually when the Found them?
Answer: The Bavli, Sota 13, says (if I understand it correctly):Come, see how beloved commands were to Moshe rabenu, for all the Jews were busy with spoils and he was busy with commands [specifically, filling the promise of taking Yosef's bones, see the beginning of B'shalach —msh210], as it says "a wisehearted person will take commands...".And how did Moshe rabenu know where Yosef was buried? They said, Serach the daughter of Asher was left from that generation; Moshe went to her and said to her "do you know where Yosef's buried?". She told him, "the Egyptians made him a metal coffin and set it in the Nile River so its waters would increase".Moshe went and stood on the Nile's bank and told him "Yosef, Yosef, the time that God has sworn 'I'm redeeming you' has come, and the oath you made the Jews swear has arrived. If you show yourself, good; otherwise, we're exempt from your oath". Immediately, Yosef's coffin floated....Rabbi Nasan says, he was buried in a royal tomb. Moshe went and stood by the royal tomb and said "Yosef, the time that God has sworn 'I'm redeeming you' has come, and the oath you made the Jews swear has arrived. If you show yourself, good; otherwise, we're exempt from your oath". At that time, Yosef's coffin shook. Moshe took it and brought it with him....
Answer: The Tosfos Shantz (סוטה יג, א) says that they took the Bones of Yosef and placed it in the skin of a כבש (Goat I Think) the Animal then came alive with Yosef Bones in it and Thats why it says נוהג כצאן יוסף.
Comment: My question is it says that the Yam Suf split when it saw the Casket of Yosef which If you think it is not a Problem its a Machlokes Medrashim.Or maybe even they took the Casket separately and thats why it split

Yosef Bones out of Egypt


What should I do if an answer is just plain wrong?

Question: I have stumbled upon this answer which is just plain wrong. I left a comment below it to indicate why the answer is incorrect and potentially destructive. Is there any other measure I should take? Is flagging the answer correct behavior in this case?
Answer: There is no need to flag it. If it's wrong, downvote it and (as you have) leave a comment explaining what the problem is. This is not something that moderators will take any action on.
Comment: Unless you have a particularly great idea, this is as good as it gets @FUZxxl. The tick mark was only ever meant to indicate helpfulness as judged by the OP. It is not a sign of correctness.
Comment: No, it is not. That's what downvotes are for.
Comment: There needs to be a better way to handle this. People will see the answer marked as accepted and there is no clear way to make visible that the content is not correct.
Comment: @Stijn I doubt that many people will review a question with an answer that has been marked as accepted. I fear that my comment will not be read by those who read the answer.
Comment: @Bart I fear that others might misunderstand that. Is it acceptable to edit the answer to indicate its falsehood?
Comment: @FUZxxl There is: leaving a comment. If people agree with you, your comment will be upvoted and the answer downvoted. I understand your frustration (having been in the same situation) but that's the way it is.
Comment: People *do* notice when the accepted answer is heavily downvoted. At least, it motivates them to read the second-listed answer, the one the community has "accepted" by upvotes. @fuz
Answer: I've also downvoted plain wrong answers, and commented on why they were wrong, but if the answer is popular and at the top of the list (or worse, accepted), it can take ages for a better answer to come up. That is, if the question isn't already closed.
Editing the answer to point out that it is no longer accurate may be morally right, but as far as I've seen, is against SO policies because it changes the overall meaning of the answer significantly. However, see this answer on historically popular but wrong answers, which suggests it may be okay to edit the wrong answer and point to a correct one.
Flagging it for moderator attention may again feel right but moderators aren't tasked with evaluating technical accuracy.
The only semi-effective measure I've found was to leave a comment on the question and ask the OP to revise the answers. You can hope they'll accept a correct one. In my experience, about half the time this was the case, while in the other half the OP has moved on and stopped having enough current knowledge, interest or time to review the answers, or was no longer active on the site.
I'm afraid this is the best we have. So do leave a comment on the question, and hope the asker will have a second look!
Answer: Judging the technical correctness of an answer is not a job for moderators, but for subject matter experts.
You can often get the attention of other subject matter experts (who will let you know if you missed something, or else add their votes to yours) in a relevant chatroom.