Could a species evolve to abandon material form?

Question: In the book 2001: A Space Odyssey, it is revealed that creatures can evolve past physical form. Could this actually happen? Could an organism actually move beyond corporeal existence? And would this new version be called a "soul?"
Comment: No longer limited by physics? Is that even a legitimate concept?
Comment: I wonder why would computer simulations, like all the humans are, would worry about that :-)
Comment: We don't currently know how to make it happen, but that doesn't mean it can't actually happen. Flying in a heavy metal machine at faster than the speed of sound was impossible in 17th century France, but if someone were to ask "could this actually happen?" we now know the answer to be "yes." Flying at faster than the speed of light was also impossible then, and we're now fairly confident that the answer to _that_ question would be "no." But someone in 17th century would have no way of differentiating between those two questions (or even a way of precisely defining them).
Comment: @HowardMiller Check the context. Look up "corporeal" for what "past physical form" means in the context of this question.
Comment: What do you mean by physical form? Gamma rays and magnetic fields are physical forms, aren't they? What do you consider to be "past physical form:?
Comment: Close voting because the soul part of the question is definitely opinion based.
Comment: -1 because this ought to win a prize for "most fundamental misunderstandings of science displayed in one short question". Answers are going to be meaningless unless the answerer does all the OP's definition of terms on their behalf.
Answer: No.
There is no mechanism known to us that would allow a creature to evolve past the point of using DNA. It doesn't rule out the possibility that the life forms could develop machines to convert themselves into energy or whatever is "past physical form". But it's not going to be a natural process.
Some might call these new creatures "souls", but it's an irrelevant designation. More likely any of the creatures remaining corporeal would have remained that way for a reason and would not treat those who have moved on with such reverence.
Comment: So the real question is whether or not magic is a thing... Strangely enough.
Comment: @RileySantos Either magic or a sufficiently advanced technology, they are indistinguishable.
Comment: Man made *is* natural. Is an anthill a natural structure? What about a birds nest?
Comment: If it is not a "natural process", is it super natural?
Comment: @SeanR In the context of evolution the terms are quite clear, for example natural selection vs artificial selection. They are different things, so they are called different things. This is how human language works. "man made" is not the same as "natural".
Comment: Downvoter care to explain?
Comment: @JensSchauder: Natural vs. man-made.
Comment: Nothing in the question states that it has to be a natural process - its entirely an arbitrary distinction. Artificial and natural selection has the same outcome - a species that differs from the progenitor.
Comment: @SeanR It's science, not arbitrary. Evolution is decent with modification. To transform in a single generation is not evolution.
Comment: Of course it is - its not 'natural' evolution (eg Darwinian natural selection in its current form) but still evolution by every other definition of the word.
Comment: @SeanR You're grasping at straws now. The question is about the evolution of a creature, *biological evolution*. At least, that is the way I'm interpreting it and my answer is entirely correct within that context. It's fine if you want to interpret the question differently, but it doesn't make my answer wrong.
Comment: Hmm, any of the four downvoters care to explain?
Comment: I have no idea why, but it was flagged as offensive. The answer or maybe one of the comments.
Comment: @Vincent Alright, thanks for looking into it. Cost of doing business on the internet I suppose.
Answer: I think there are actually two questions here:

Can an organism exist that is non-corporeal?
Can an organism evolve to become non-corporeal?

As you can see, the second question really depends on the first. I would say that as we have no examples of non-physical life-forms, it's really hard to say if they're possible. I mean, just think about it, what would they be made of? Nothing, of course. But if they are something, then what? Maybe they're made of light, or energy, or some other thing that exists that is not matter. I don't think this question can be very satisfactorily answered, so let's assume it's a yes.
The next question, about evolution, brings to my mind the concept of intermediate forms. Between physical and not physical there has to be some sort of middle ground, some sort of half-physical missing link. Over many generations, your organisms will have to become less and less corporeal until there is nothing physical left.
Again, without knowing the final form of this organism, it's hard to say if this could be accomplished, but I would at least like to point out that non-corporeality should be immediately beneficial in some way. If your demi-corporeal creatures can't mate with anyone, or can't defend themselves or sustain themselves, and can't do all of these things better than the competition, then it's very likely any non-corporeal mutations won't last.
A far more probable method is to achieve non-corporeality through artificial evolution. Just look at humans: we developed larger brains for a long time, then in the last century we massively increased our thinking power not through evolution but through the invention of computers. For a long time, human ingenuity has achieved more for our species than evolution could accomplish in millions or even billions of years. We've even been able to create things that don't directly, immediately benefit ourselves, such as space travel. I think that if non-corporeal life-forms exist or ever will exist, it will be not through evolution, but through the inventions of a highly intelligent species.
(slightly tangential)EDIT: Thinking about souls got me to considering the possible example of a human being as an intermediate form between physical and non-physical. In Christianity, animals don't have souls, and since humans evolved from animals (I realize the possible contradictions here, just go with it), it stands to reason that at some point in time humans evolved to have souls. Keep in mind that the intervention of a soul-creator such as God would fall under my last point, of artificial evolution, so let's assume God sat back and let it happen. It is believed that the soul is created upon conception, but lives on after death, so it seems like the body is only needed at the beginning of life, and may be discarded almost immediately, which sounds like we're pretty close to evolving past physicality.
The thing is, the soul seems more like a parasite than part of the body. It only uses the body as a means to procreate, kind of like how a facehugger can only give birth into a human's stomach. If humans evolve to be completely non-corporeal, it would be more like the parasite evolving to be self-sufficient, but since the soul was never physical in the first place, that jump from physical to non-physical wouldn't have happened.
Comment: @Samuel Only the ones that get baptized. Turns out holy water is a breeding ground for souls.
Comment: Gotcha. If it isn't influenced by physics, ya can't find it, thus, we haven't.
Comment: Your tech argument is exactly like the book. :)
Comment: So, wait, all dogs do **not** go to heaven?
Comment: @DaaaahWhoosh That's why I always leave a [BT dunk](https://en.wikipedia.org/wiki/Bacillus_thuringiensis_israelensis) in mine
Answer: Turn their consciousnesses into computer programs.
Samuel argued that there is no known way to evolve beyond using DNA, while DaaaahWhoosh recommended artificial evolution. I agree with them both, in that I believe that nature will never move beyond physical, organic forms. However, the organisms themselves can use advanced technology to do so - namely, computers!
According to some answers here, this might be possible - at least, it might be possible to transform consciousnesses into software programs. The requirements here seem laxer, though, so I think the odds are better. To be able to say that a being has become a computer program, there are a side few requirements that must be satisfied:

The things that make the being unique (its genetic code) must be represented. This can be done by representing DNA by binary code.
The being must be able to take in input from its surroundings and influence its surroundings. This can be done by auxiliary devices controlled by the being. This emphasizes one important point: The creatures obviously still need something in order to run (namely, hardware), but they themselves are about as un-physical as possible.

Whether or not this method is valid is, like all other suggestions here, a philosophical question, but I feel like it is valid. After all, would you call a string of ones and zeros physical?
Comment: I don't know when or how this might be possible, but I have to agree - this is the only method that seems like it might someday be possible.  We're still a long way from it though.
Answer: I'm thinking... yes. No. Depends. Can your species evolve to, as in 2001, make technology to do this? We won't know for a long time. But if you believe in 'souls,' then it could be accomplished by slowly dropping the reproductive 'creatures' down to zero. At this point, with no physical mass, they would no longer have any ability to make more of themselves, evolution's biggest spiel. But on the other hand, with no matter, or corporeal form, they wouldn't have to worry about that.
Comment: @HDE226868 Extinction, presumably. If creatures have souls and they all die, then the souls aren't bound up in physical bodies. Voila! Transcendence.
Comment: *slowly dropping the reproductive 'creatures' down to zero.* - What do you mean by that?
Comment: Yes, that there
Answer: The answers to this are frustratingly dependent on the specific definitions of words that we tend to like to think need no definition, like "evolve," "existence," and "soul."  Accordingly, expect no final answers.
That being said, there's a tempting approach to consider for defining some of these concepts.  In particular, consider what it means for a being to be "corporeal."  It tends to vaguely mean they have matter, but when you consider an empirical meaning to the word, it has to deal with how things interact.  We can't detect matter directly.  We detect their interactions, whether gravitational or electromagnetic, or otherwise.  We can see that an object is between us and the sun because we believe we should be seeing photons from the sun, and we are not seeing them.  Thus, we presume something must be blocking them.
From this approach, "corporeal" has picked up an interesting meaning.  Now it means that a third party cannot detect any interactions they would deem corporeal.  This fits quite well with the definitions needed for 2001: A Space Odyssey.  A creature would be deemed incorporeal if we have no way of detecting the presence of their corporeal body.
Of course, to be interesting, such a body does need to interact with the world.  We can presume infinite such bodies that do not interact, but the interesting cases of incorporeal entities, such as ghosts, do interact.  They just do it in a way that is hard to trace causally to matter that is categorized as "part of their body."  To have meaningful interactions with the world, such a being would have to understand the world around them well enough to find ways to amplify the tiniest interactions, and then be "elsewhere" before someone can causally trace what they've done.
Why might an individual undergo such a transformation?  One benefit of this approach is that it is remarkably efficient with energy.  One always applies the absolute minimum amount of energy possible to solve any particular problem.
Interestingly enough, efficiency of energy usage is oft cited as a desire.  This suggests that not only is there a possible path to incorporeality, that it might actually be along the path of any given martial art, reigion, or any other social structure which extols the virtue of efficiency.
Comment: Maybe a corporeal being is one that can be hit with a stick.
Comment: @Samuel True.  In that case, we would be focusing on electromagnetic interactions which acts to prevent other matter from entering a defined volume according to the correct conservation of energy and momentum equations.
Answer: The foremost thing to realize when discussing a question like this is that you're asking whether it can happen, which is actually a question about two things:

What is a consciousness/individual?
What do we not know about the world?

And unsurprisingly the answer to both is that we don't know. Like seriously, popular media might try creating the illusion that the consciousness is just the brain and that it's all perfectly understood, but at university in our introductory course about human physiology literally every second paragraph about the brain finished with 'we don't get this yet'. We have no idea what a free will is and our theoretical deterministic models do not match the models we believe in and act by. And the same goes for the second point, we obviously do not know what we do not know, so saying what realistically could be discovered in the future is a terrible question (and yes, I did downvote the question because of this).

But a far more interesting question and on-topic question on worldbuilding.SE is about how you can justify such an evolution in a story. The first thing to look at then is which things are mass-less (thus without material form) and then create some kind of network which at least at some level resembles the human brain. Within those boundaries you can probably come up with a justification for about anything. Let's go with light as our mass-less basis (or any other form of radiation), it can interact with other light reflect around a bit, etc. A creature in such a model would then be maybe as big as a couple of galaxies and thought processes would probably be really slow. Evolving into such a create could be either 'natural' or artificial. In the first case you could for example claim that there is a creature which emits light naturally to originally communicate and as this communication becomes more and more complex and starts to span more and more generations a point can maybe come where this network of interacting light starts to have it's own consciousness (if that's how you define conciousness in your world). In the second case it's far easier and you can simply state that either God or scientists sat down for a bit and helped such a process along.
Now, all of that assumes that you wish to keep point number 2 in check as much as possible and keep the knowledge in-universe similar to knowledge in the real world. Both realistically speaking and story wise this of course entirely unrealistic, so if you want you can simply think up an alternative form of being in which a creature exists and set up artificial rules to reach such a state of being (e.g. as with Stargate). Technically speaking this could be considered more realistic than the first option, however it will feel more alien and thus unrealistic (scifi-y) to most readers.
Which kind of approach you choose is all up to you, but that's the cool part about creating worlds about stuff we don't know: You have a lot of freedom, just be aware of this freedom and don't let sciencism limit you.
Answer: Maybe some species already have evolved this way. How would we know?
I'm having a hard time trying to come up with a reason why a species would evolve this way. Evolution is largely driven by adapting to the environment, so what in the environment would lead to this? Evolution also takes thousands if not millions of years. During the transitional period, until we finally shed our bodies, are we going to be partly physical and partly not?
The coelacanth has been around for roughly 400 million years. You would think that if any species was going to move beyond corporeal existence, it would be the one that has been around for the longest time. But not the coelacanth. Maybe it just isn't trying hard enough.
Comment: Why? because the physical form is frail and has an annoying tendency to be damaged or even die. So without the physica form, there is less damage to be avoided, which leaves more time to for example look at cat pictures.
Comment: And even better, to fart around in space without the constraints of physics.


Is "Viking mythology" the same as "Norse mythology"

Question: Does "Viking mythology" and "Norse mythology" mean the same, or are there any differences?
The Norse deities were: Odin, Thor, Heimdall... Does it mean, that the Viking deities were them too?
Comment: Vikings were all Norsemen, but not all Norsemen were Vikings.  (See @solsdottir's answer.)
Answer: A "Viking" was a a warrior who went raiding abroad. (See the Jorvik site for more on this.) They were probably the most famous medieval Scandinavians, but they were a small subset of all the Norse people.
Having said that, warrior gods would have been closest to their hearts, and Michael Enright has theorized that the rise of the god Odin was linked to the cultural and religious rise of warbands with a charismatic leader. (You'll notice on the show Vikings that Ragnar Lothrbrok has a close connection to Odin.)
So while farmers would have mainly worshipped Frey or Thor, and merchants and sailors probably focused on Njord, warriors certainly focused on Odin.
Comment: haha. I never thought of answering this way--the question is a little ambiguous. In light of that ambiguity, this is probably a good answer!  (PS nice Ragnar Lothrbrok reference.  I loved the way they presented him with Rollo and Floki as an Odin/Thor/Loki triad.)
Comment: Yes, you could see why they would prefer Thor or Frey. I enjoyed the Odin/Thor/Loki bit of Vikings, too.
Comment: @Iter Ator Odin is a fairly terrifying figure--ruthless, bloodthirsty, and often quite treacherous. He was not considered to be beloved of the common folk.
Answer: Snorri Sturluson would likely have had some thoughts on the subject.
Norse Mythology generally refers to stories about the Gods and Giants, codified first in the Poetic Edda, and later in the Prose Edda. (There are several English translations of both, but my favorite is Kevin Crossley-Holland's "The Norse Myths".)
"Viking Mythology", if I understand your meaning, would likely refer to the Sagas, which are often, but not exclusively, generational stories of heroes. Many of the Icelandic Sagas are concerned with the history of the settlement of the island.
I bring up Sturluson because both the Prose Edda, and sagas such as Egil's Saga are attributed to him.
Comment: Should be noted that Snorri Sturluson was a Christian and may or may not have been influenced by Christian philosophical ideas of his time. Though no doubt he does provides good insight into Norse mythology.
Answer: It's actually a very interesting question. The only documentation regarding these people is from the Icelandic sagas who were principally Norwegian people fleeing the oppressive taxations imposed by King Harold Haradri. However, I think it's a safe bet that everyone was singing from the same hymn sheet and that they are one and the same. All over Scandinavia the only grave finds have been inscribed in the Norse Futhark (like running writing) and always the only deities they refer to are in the pantheon of Norse gods.
There is a school of thought that intimates that most religions in fact only worshipped one god and that other 'gods' are only supposed to be taken as aspects of that one god. A point to note is that historically ordinary people were told about the affairs of gods by the priests. That pecking order has only really been changed with the advent of the Christian church. Although it might be thought that Christianity came to Scandinavia with the introduction of various Christian missionaries intent on bringing god to a host of barbarians there is another school of thought held with some credibility by myself that the Norse were Christians, that for Odin read Jesus, that when in the Bible god disowned the Jews who had been his chosen race that he then made the Vikings his chosen race, beginning with Jesus/Odin (who was (killed?)by the jews) and tasked them to spread there seed around the world (note that the Norse were the only society in history that did not have capital punishment. If a Viking killed someone he was banished not executed). The Vikings spread into the UK, the Viking Rus formed what is now Russia, the Normans came from Scandinavia. These areas were the western Europeans that conducted the Crusades, these areas went and colonised America, Australia, New Zealand. So in hindsight whose seed has now been spread around the world?
If you're wondering about the Vikings first visits when they butchered the priests at Lindisfarne and subsequent monasteries etc., the people they butchered were the only ones that had vast deposits of gold with abbots that lived like kings whilst the average person struggled to feed his family. Maybe these initial Viking raids were heaven sent.


Can a Knob & Tube live hot wire be left disconnected without the neutral in a switch box?

Question: Can a live (capped) knob & tube hot wire be left disconnected, without the neutral (it's removed) in a new switch box now fed by a modern 20amp circuit and romex?  The reason it is still live is because the circuit operates other lights in the house.
Comment: What is the general condition of the live knob & tube wires?
Comment: Does the portion powering lights have it's own neutral? or is it sharing another neutral?
I would not do that if so.
As for being disconnected in a box without a neautral, this means you have 1 leg or power there which can do nothing harmful unless shorted out nor anything beneficial without its other side/ leg of power.
Answer: Knob and tube is no longer listed and approved, it should be de-energized and abandoned when encountered within the scope of any new work after being replaced with listed cable assemblies suitable for the location (in your case, non-metallic bonded cable, aka Romex).
That said, it sounds like what you have in the box used to be a switch leg where the original knob and tube feed part of the leg is no longer present (hence, the absence of the neutral), and through the process of removing it the lighting circuit was changed so that the leg ended up being always hot. What you should do is just disconnect it from whatever fixture is now back-feeding it. Be gentle, that stuff is brittle and the insulation can just disintegrate in your hands as you handle it.
If that's the case, then you probably don't have a multi-feed (two circuits on the same phase sharing the same neutral) going on, it was just a switch leg, but you should probably consider retiring the rest of the old wiring anyway.
If you can't find where it's being fed, your immediate concern is now to ensure that the box is suitably grounded if it's metallic, you can test this by attaching one end of a voltage tester to any known hot leg, and the other to the box itself. You should read around 120V and be able to confirm the presence of some kind of physical ground connected to the box. If that's not the case, call an electrician and have them straighten it out.
Still, the best guidance in these cases is just get rid of it where / when you see it, especially if it's been disturbed recently. That old feed is probably not going to cause you any problems, but please consider erring on the side of caution and having that old lighting circuit re-fed.


Anonymous user cache control

Question: We have written some custom blocks that render dynamic content; unfortunately, the caching defaults cache the first render of this block (and don't refresh for anonymous users). Cache control seems to only work for authenticated users. Are we missing something obvious? Is it possible to control anonymous caching on a block (or page) basis?
Comment: Is the block implemented in a module?
Answer: There are two different page caches.
The Internal Dynamic Page Cache works with all kind of elements like blocks and nodes and is uses the cache tags, cache contexts and cache max-age provided by these elements.
The Internal Page Cache is for complete pages for anonymous users and only uses cache tags.
You can control the page cache for anonymous users with one parameter.
Go to the perfomance configuration:
admin/config/development/performance

And configure the page cache maximum age with the time how long your information is valid. This is also important for proxies and the browser cache, because it would not help to invalidate the drupal cache, if the page is cached in other places. After that time the page expires and should be built again. According to the documentation:

Configuring the internal page cache On the Performance page, you can
  configure how long browsers and proxies may cache pages; that setting
  is also respected by the Internal Page Cache module. There is no other
  configuration.

But this is not true. You should configure this time for proxies and browser cache, but the internal page cache does not respect the time you set there. The only reliable solution I found is to uninstall the module Internal Page Cache or set an expire time in an EventSubscriber (for example 3600 sec in the future):
/src/EventSubscriber/SetExpiresSubscriber.php
<?php

namespace Drupal\mymodule\EventSubscriber;

use Symfony\Component\HttpKernel\Event\FilterResponseEvent;
use Symfony\Component\HttpKernel\KernelEvents;
use Symfony\Component\EventDispatcher\EventSubscriberInterface;

class SetExpiresSubscriber implements EventSubscriberInterface {

  public function onResponse(FilterResponseEvent $event) {
    $request = $event->getRequest();
    $response = $event->getResponse();
    if ($event->isMasterRequest()) {
      $request_time = $request->server->get('REQUEST_TIME');
      $expires_time = (new \Datetime)->setTimestamp($request_time + 3600);
      $response->setExpires($expires_time);
    }
  }

  public static function getSubscribedEvents() {
    $events[KernelEvents::RESPONSE][] = ['onResponse'];
    return $events;
  }

}

mymodule.services.yml
services:
  mymodule.setexpires:
    class: Drupal\mymodule\EventSubscriber\SetExpiresSubscriber
    tags:
      - { name: event_subscriber }

Comment: You can disable the internal page cache with \Drupal::service('page_cache_kill_switch')->trigger(). Of course, if your block is displayed on all pages then that's kinda pointless.
Comment: You could also use a "RequestPolicyInterface" class to deny caching according to some parameters and the request. See https://api.drupal.org/api/drupal/core!lib!Drupal!Core!PageCache!RequestPolicy!NoSessionOpen.php/class/NoSessionOpen/8.2.x for more information.
Comment: Yeah, the page_kill_switch helped us out! Thank you!
Comment: @gavz When using the switch, test with `curl --head`, that `max-age` is correct in `Cache-Control:`
Comment: To let the performance page settings control the internal page cache expiration, the service's `onResponse()` method in this example could be updated to use `$page_max_age = \Drupal::config('system.performance')->get('cache.page.max_age');` instead of hard-coding the expiration to a fixed number of seconds in the future such as 3600.
Comment: In my case with both both Internal and Dynamic Page Cache enabled with max age 0 under config/performance. I also was trying to use a computed field value whose default value for "cacheMaxAge" was set to -1. This seems to translate somewhere like Sun, 19 Nov 1978 05:00:00 GMT in the expires header. Also the X-Drupal-Dynamic-Cache header was set to HIT for anonymous users. I was able to set to MISS by using some thing like $this->invalidator->invalidateTags($event->getResponse()->getCacheableMetadata()->getCacheTags()); where $this->invalidator is the injected @cache_tags.invalidator service.
Answer: Check out Added 'no_cache' route option to mark a route's responses as uncacheable
In your routing.yml file:
some.route:
   path: '/some/path'
   defaults:
     _controller: '\Drupal\Some\Controller::response()'
   options:
     no_cache: TRUE

Comment: Is there a way to achieve the same outcome, no_cache: TRUE for a particular path, but via theme-level preprocessing?
Answer: If you need the Internal Page Cache enabled (i.e., you can't use Varnish or another memory-based solution), and you simply want Internal Page Cache to respect the time set on at admin/config/development/performance, you could add your own Event Subscriber that modifies the FinishResponseSubscriber that Drupal provides. You can even use Drupal Console to generate most of the Event Subscriber for you, and then take the other bits from FinishResponseSubscriber. Your result would look something like this:
/**
 * Class MyModuleSubscriber.
 *
 * @package Drupal\my_module
 */
class MyModuleSubscriber implements EventSubscriberInterface {

  /**
   * Sets extra headers on successful responses.
   *
   * @param \Symfony\Component\HttpKernel\Event\FilterResponseEvent $event
   *   The event to process.
   */
  public function onRespond(FilterResponseEvent $event) {
    if (!$event->isMasterRequest()) {
      return;
    }

    $request = $event->getRequest();
    $response = $event->getResponse();

    $this->setExpiresNoCache($response);

    return;

  }

  /**
   * Disable caching in ancient browsers and for HTTP/1.0 proxies and clients.
   *
   * HTTP/1.0 proxies do not support the Vary header, so prevent any caching by
   * sending an Expires date in the past. HTTP/1.1 clients ignore the Expires
   * header if a Cache-Control: max-age= directive is specified (see RFC 2616,
   * section 14.9.3).
   *
   * @param \Symfony\Component\HttpFoundation\Response $response
   *   A response object.
   */
  protected function setExpiresNoCache(Response $response) {
    $response->setExpires(REQUEST_TIME + 300);
  }

  /**
   * Registers the methods in this class that should be listeners.
   *
   * @return array
   *   An array of event listener definitions.
   */
  public static function getSubscribedEvents() {
    $events[KernelEvents::RESPONSE][] = array('onRespond');
    return $events;

  }
}

The above hardcodes the cache lifetime at 300 seconds, but you could easily retrieve the user setting instead.
Comment: > "You can even use Drupal Console to generate most of the Event Subscriber for you,"
What do I need for? Modul, Controller? Where to past this codec?
Comment: Hi @FrankGiesecke, there are a number of ways to get Drupal Console. See https://drupalconsole.com/
Comment: Hi, Console runs now.
Which files Do I still need?
Answer: I think you need to disable the 'Internal Page Cache' module to get cache contexts working.
With 'Internal Page Cache' enabled content for anonymous users is cached by default.
If you turn off 'Internal Page Cache' you still need to tell Drupal to not cache for anonymous users
$variables['#cache'] = [
  'contexts' => [
    // The "current user" is used above, which depends on the request,
    // so we tell Drupal to vary by the 'user' cache context.
    'user',
  ],
];

does it for me - but is probably not sompletely correct.

Anonymous user cache control


long distance cat5 run

Question: I need to run a cat5 cable 400'. I know this is just a little over the 325' that the 'standard' says cat5 can do, and will probably work. But we'd like to make sure this isn't a weak link in the system. Can I just put a simple switch in the middle as a signal boost or do I need a specialized 'repeater'? If so, what product am I looking for?
Answer: A simple switch should do the job. So would a hub.
From the point of view of signal amplifying, all work the same. It all comes down to the price.
Answer: A simple switch will work. The limit is per segment, and a switch generates different segmetns on every side.
Answer: 75 feet isn't just "a little" over the limit, it's 25% over the limit. That being said, a switch in the middle should be all you need.
Comment: Plus the standard restricts how close to other cords the e5 cable can be placed. Which will add the overhead.

long distance cat5 run


Does a gravitational wave loses energy over distance?

Question: How does a gravitational wave travel over vast distances without losing its energy? Could they go on forever as long as the Space?
Thank you
Comment: all waves (propogating fields)  travel without losing energy until there's something to interact with
Answer: tl;dr: Yes. Feynman's beads on a string argument
The other answers skirt what I think is the issue that the OP is asking about. In a lossless medium a spherical wave packet itself, caused by a disturbance, will not "loose energy" itself. If you integrate over a large volume you get a constant energy versus time. Of course the flux per unit area will decrease by the same rate that the area increases, but that's a trivial result.
But, when gravitational waves pass matter, they really do deposit energy in the matter, and thereby become attenuated. The effect is very very tiny for a given amount of matter, but it is non-zero and the universe is pretty big.
In this answer to the question Transfer of energy from gravity back to other "more familiar" forms of energy? I've said:

This is from the Wikipedia article mentioned.
  I think this is really worth reading, as it not only describes some of the physics associated with the accepted answer and it's citation of Feynman's argument about a bead a stick, but perhaps gives a little insight into the development of the field as well.

Feynman's argument
Later in the Chapel Hill conference, Richard Feynman — who had insisted on registering under a pseudonym to express his disdain for the contemporary state of gravitational physics — used Pirani's description to point out that a passing gravitational wave should in principle cause a bead on a stick (oriented transversely to the direction of propagation of the wave) to slide back and forth, thus heating the bead and the stick by friction. This heating, said Feynman, showed that the wave did indeed impart energy to the bead and stick system, so it must indeed transport energy, contrary to the view expressed in 1955 by Rosen.
In two 1957 papers, Bondi and (separately) Joseph Weber and John Archibald Wheeler used this bead argument to present detailed refutations of Rosen's argument.(5)(6)

(5) Bondi, Hermann (1957). "Plane gravitational waves in general relativity". Nature 179 (4569): 1072–1073. Bibcode:1957Natur.179.1072B. doi:10.1038/1791072a0.
(6) Weber, Joseph & Wheeler, John Archibald (1957). "Reality of the cylindrical gravitational waves of Einstein and Rosen". Rev. Mod. Phys. 29 (3): 509–515. Bibcode:1957RvMP...29..509W. doi:10.1103/RevModPhys.29.509.
Answer: In empty space, just like a light wave, they spread out, becoming less intense as they get further from their source, but never vanishing completely. At some stage the waves from a distant event might become undetectable in local noise, or so weak that quantum effects might become relevant, but essentially they never die out.
As @uhoh points out, they do lose some energy when they interact with matter.
Comment: This is wrong. See my [answer](https://astronomy.stackexchange.com/a/28550/7982).
Answer: It's a wave, and like any other wave, it loses flux (power over area) with the square of the distance. That is, if you double the distance it travels, your wave will have a quarter of the flux it had. If you triple the distance, your wave will have a ninth of the flux it had. This is a property of waves and can be observed in light intensity, sound, and any other wave.
Technically, the wave will never fully dissipate. If the wave travels a million times the distance, the wave will weaken to one trillionth of what it was. Still not zero, but very tiny nonetheless.
Comment: Energy is conserved. You mean the flux (power per unit area) decreases. Note also that gravitational wave detectors detect amplitude not intensity.
Comment: @RobJeffries You're right, I used the words interchangeably when I shouldn't have. I'll correct it.
Comment: This is wrong. See my [answer](https://astronomy.stackexchange.com/a/28550/7982).


Highest current raspberry pi can take from usb

Question: I'm going to be working on a project from a DC power supply, and I need to know the maximum current the Raspberry Pi can handle from the USB port. I know my wall wart adapter that came with my Pi outputs 5volts at 1000mA, but how high can I crank up the amperage without destroying my Pi?
Comment: Do you mean you want to *back-power* the pi via the USB ports? http://elinux.org/RPi_Hardware#Power (3rd list, 4th bullet point)
Answer: Current (amperage) doesn't work like that. The device draws the current it requires, and the power supply needs to provide that or higher. For example, if you were to switch to a 2A (2000mA) supply, it would operate fine (assuming 5V of course).
So the answer is there is no limit. Just make sure you provide the appropriate voltage and at least the actual current the Pi (and any attachments) will require.
Comment: There is probably a limit (though I don't know what it is) to the amperage the Pi can pass on to the attached USB/GPIO peripherals though.
Comment: I took the question to mean "how much current can be supplied to the mini-USB power input". If the question is "how much current can be drawn from one of the on-board USB sockets", then yes, there is most definitely a limit.
Answer: there's a short-circuit protection polyfuse, that's supposed to trip when the current drawn from the power supply exceeds 1.1A (constant, or a little bit higher for the short bursts). considering the RasPi consuming about 0.7A, your project may safely draw about half-an-ampere.
if you shorten the polyfuse, you may get higher currents, provided your power supply can handle them, but you may eventually burn and damage PCB tracks depending on how high you'd go.
also, earlier versions of RasPi included separate 150mA polyfuses for every USB port, you may check for these if your board is not a recent one.


ubuntu 13.04 - can't see external ntfs drive

Question: I have upgraded from ubuntu 12.10 to 13.04 (x64) and from kde v4.10 to v4.11. Same kernel 3.8.
Since the upgrade I have an issue with my Verbatim store'n go 500Gb usb external drive recognition, it takes a lot of time before recognize my external drive. I'll give you some more informations:

it just happens with my external drive and it does not with my usb pen drives
it happens on ubuntu but it works well on windows 7 (windows 7 immediately recognizes the external drive as it does with other devices) so it's not related to my external drive
it's not related to my usb port because it's the same I use to connect the same external drive on windows 7
it doesn't happen with other external drives (so it's very strange now)
The same external drive was immediately recognized with ubuntu 12.10
it's not related to the desktop environment because I have the same issue with unity
sometimes the drive is seen with 'sudo fdisk -l' but it's not recognized from the file manager (same thing with unity and kde)

How can I solve it?
edit:
here is /etc/fstab:
http://pastebin.com/raw.php?i=QPawt31b
and this it /proc/mounts: http://pastebin.com/raw.php?i=Ub4F1XuW
Thanks
Comment: What is the output of */proc/mounts*  when the drive is plugged in? What is in */etc/fstab*?
Answer: It's seems (but not sure) that Ubuntu changes the way the devices are mounted now using subfolders for each user in /media
So if you launch Nautilus as root and see your files so just it's a matter of rights.
try this from a shell:
<code>sudo -i nautilus --no-desktop
</code>


My scenes seem too fast

Question: I'm having issues because while I'm in the process of writing I think my style has enough length to it, but when I go back and read my work it feels extremely fast. A scene I expected to take me fifteen minutes to read is over as soon as it started. Especially with dialogue. I enjoy writing dialogue so much—- when I hear it in my head, there are so many beautiful pauses, like the way an actor will let the silence hang for dramatic effect—- but apparently, I'm not translating that onto the page. Any tips on how to make scenes move slower (more specifically, dialogue) would be greatly appreciated. If anyone wants to see an example, just ask.
Comment: Welcome to Writing.SE, Grace! Glad you found us! Take a look at our [tour] and [help] pages, they're useful. :)
Answer: You say that in your head there are pauses in the dialogue, but in the text they just aren't there. Well then, insert the pauses.

'How terrifying!' said Frodo. There was another long silence. The sound of Sam Gamgee cutting the lawn came in from the garden.
  'How long have you known this?' asked Frodo at length. 'And how much did Bilbo know?'
J.R.R. Tolkien, The Lord of the Rings, book I, chapter 2 - The Shadow of the Past

"There was another long silence. The sound of Sam Gamgee cutting the lawn came in from the garden" provides a long pause. "asked Frodo at length" provides a shorter pause, a breath in the middle of the passage. When a description interrupts a dialogue, we perceive it as a pause in the dialogue - there's something while the dialogue holds. So when you imagine your character pausing, you break the line of dialogue with "he said", or with something longer, depending on the length of the required pause.

'When did I first begin to guess?' he mused, searching back in memory. 'Let me see – it was in the year that the White Council drove the Dark Power from Mirkwood, just before the Battle of Five Armies, that Bilbo found his ring. (ibid)

"Let me see" and similar interjections are also a way of inserting a pause. Even "well" will do.
Punctuation is also your friend: you can use em-dashes are your particular friend, but there are also commas, semicolons and periods.

'Known?' said Gandalf. 'I have known much that only the Wise know, Frodo. But if you mean "known about this ring", well, I still do not know, one might say. There is a last test to make. But I no longer doubt my guess. (ibid)

Another tool you have is repetition. By stalling in place, as it where, by using the same word or different words to say the same thing, by elaborating on the same point, you slow down the transfer of information. Instead of running forwards, the conversation stays in place. Everything feels slow and measured, rather than rushed. This can also be used to make a point stronger - it stays in our mind if it is repeated.
Read dialogues that feel slow and measured (I didn't choose this dialogue at random), and notice how the effect is achieved. There are multiple tools at play, all mixed together. Once you can recognise them, try to apply them to your writing.
Comment: Thank you for your help. I have been using similar techniques, trying to fit in a description between sections of dialogue, or simply saying "I fell silent" or whatever. I will take your advice and try to read other's work to get ideas.
Answer: Read something you wrote a year or more ago.
It is entirely possible that the reason your recently written dialog is racing by so fast is that you are very familiar with its content.  When your eyes touch the first few words of a sentence, you already know how the sentence will end, so you skip the tedious reading time and just dump the content from memory into your narrative.
By reading something older, something that you haven't thought about for a long time, you can avoid such lazy reading and actually proof/experience your words at their intended pace.
You might just find that your pacing is fine when you actually take the time to read your words.
Comment: @Grace: do not over think your work.    there is a reason why a lot of great writers wrote their best work while drunk or enraged.    you can't be inhibited when you write.  you can't over analyze.   you have to hone your craft and just let your words soar.
Comment: Thank you for the speculation, maybe this is the case, since I seem to get more dissatisfied the more I re-read my work.
Comment: I had this thought as well... It's kind of the same feeling you get when you watch the same movie close to the first time you watched it.   Especially in the emotionally high moments where you waiting to see what happens next.  The first time you don't know what's coming so a brutal fight sequence might seem like it goes on forever... when you rewatch, it becomes decidedly quicker cause that anticipation of what is going to happen is gone...
Answer: Grab a friend or family member and print out the scene so you each have it on paper.  Ask the other person to read it out loud, acting it out to some degree.  Was there a pause in your head that your reader just missed?  Circle it on your copy.
Have your partner take one character while you take the other (add people or double up on characters if you need to).  If beats are missing, you'll hear it.
Now, try the passages different ways.  Play with it.  How much time do you actually need for it to feel right, as if it were dialogue in a movie?  Of course you don't want a scene that would take 15 minutes in a movie to take 15 minutes to read, but you want the reader to feel that that amount of time has gone by in the character's world.
Intersperse your dialogue with narrative.  It helps break things up for the reader too.  If there's a pause in the conversation, show the reader what your viewpoint character is looking at, or thinking.  Or use the narrator to add descriptions of the setting.  Make sure these things add to the story and aren't just filler.
These elements can be directly about the passage of time or they can just move the reader's focus for a bit, which has a similar effect.  Use paragraph breaks when jumping from one element to another or when narrating that significant time has passed.
None of your scenes should be very long though.  Fifteen minutes is forever both in a movie and in a book chapter.  It's okay if the writing is sparse as long as you convey the passage of time.
Answer: This has been an issue for me as well. As the writer, you bring a wealth of context to each word that isn't present for the reader, unless you put it on the page. If all you're writing is dialogue, you'll end up with a script, not a book --something that will be incomplete unless some actor puts in the work to bring it to life.
With that said, the answer isn't just to add pauses or actions. That's still just more stage directions. What you need is to put your reader in the setting, and in the mindframe, and in the attitudes, and in the histories of the characters. (Along those lines, here's a a similar question I asked a while back --I found the accepted answer, by @Amadeus, very helpful.)

"Would you like..." she began, as she fumbled in the pocket of her rough, homespun dress.
In those few seconds as I waited in anticipation of her next words, I mentally filled in my own answers. "A million dollars?" Of course I would. "My heart?" Well, we hardly knew each other well enough for that. "A piece of hard candy?" It seemed appropriate enough to the dress, but although she was attired like someone's farm-dwelling grandmother, she wasn't anywhere near old enough to start filling her pockets with candies.
Of course, it was none of these. Out of the old-timey pocket came a perfectly modern smartphone, and she finished the sentence as she called up her app. "Would you like to donate to my Kickstarter?"
I sighed and nodded as my heart sank.  "What are your donation levels?"
Answer: Thinking about it.
This bit expands on Chris Sunami's suggestion, one way to extend the dialogue is to describe the thoughts and feelings of the POV character as the dialogue progresses, or as the scene progresses.
We are presumably following some character, or several characters, that are not wooden posts, and care about and think about what is being discussed. Along with the setting, along with adding the pauses, this is another element that can be discussed.
Many long silences exist because someone is thinking through what was said, or is experiencing emotions about what was said.
Usually when people pause in the middle of saying something, they aren't brain dead for three seconds -- They are struggling for the right words, or to not give offense, or deciding whether they should say anything or not. Even if they are not the POV character, the POV character can be guessing at which of these reasons apply, or assuming one and taking offense anyway:

Bill said, "I just think, Stan, if you do --"
Bill stopped and grimaced, struggling for a word.
Trying to think of way to not call me stupid.
Bill continued, "-- it could backfire."
'Cause it's stupid, right? Screw you Bill!
Stan spoke calmly. "I'm not stupid, Bill. I've thought this out."
"I don't think you have," Bill said.

TENSION: Conflict, argument, disagreement, intrigue, concealment, deception, the search for knowledge, a search for connection, negotiation and rejection.
A second thing that has not been mentioned is the need for disagreement in dialogue. Conflicting plans, disagreement over the facts, arguments about whose idea is better or why an idea isn't going to work.
Dialogue without tension is passive, flaccid, and gets skimmed, and in the worst cases is just an info dump. Dialogue should be some kind of struggle, whether it is in romantic pursuit or facing down a villain, telling a parent they are an alcoholic that needs help.
It doesn't have to be over-the-top fraught, but even friendlies can disagree or want different things; and dialogue that is planning a future course of action can be inherently tense; people are accepting roles and responsibilities they will have to meet. They should seldom agree lightly, and often should negotiate, demand concessions, or exact a price, or try to strike a bargain.
Tension engages a reader, puts them in the mind of what they would do or say in the same situation. It is also your opportunity, as an author, to come up with something clever for your character to say, instead of a knee-jerk response.
Tension for non-dialogue scenes and description.
You can add tension, and interest, even to the description of a landscape by having a character's thoughts contrast it with similar landscapes, situations, memories it evokes. A warrior standing on a new street will see it differently than a merchant; the warrior can see things in terms of tactical advantage if a battle were waged here, prioritizing the assets. The merchant is assessing where best to set up shop, and what shops are missing, or not doing well, or look profitable.
On the trail through the woods, the princess is looking for flowers and birds and thinking it is a nice day, her guard are looking for brigands in trees, behind bushes and rock formations and thinking it's a nice day for an ambush.
You can filter your prose through the eyes, thinking and emotions of a character in order to add tension. Tension helps keeps readers from being bored by endless description. A character can sense conflict with their environment.
Comment: :) --that earlier answer was one of the most helpful I've received on this site
Comment: I *did* focus on the characters' inner life in my answer. But in all fairness, my answer --as I mentioned --was heavily based on an earlier answer you made to one of my questions. :)
Comment: @ChrisSunami Repaired.

My scenes seem too fast


Specific heat capacity at constant volume VS constant pressure

Question: For an ideal gas, why is the specific heat capacity at constant volume lower than the specific heat capacity at constant pressure?
Comment: I have not yet learned about isothermal compressibility, or that much about partial derivatives in detail. I was hoping for a simpler explanation, possibly including the ideal gas equation $PV=nRT$ and/or the heat equation involving specific heat capacity $Q=mc \Delta t$. @ACuriousMind
Comment: What about the [Wikipedia article on relations between heat capacities](https://en.wikipedia.org/wiki/Relations_between_heat_capacities) does not satisfy you?
Answer: The simple answer, which is what I think you're hoping for is the following: At constant volume, the system (by definition) is not able to do work on the surroundings because work involves a change in volume. All the heat you put in is spent raising the temperature (internal energy).
At constant pressure, some of the energy you put in goes into raising the temperature (internal energy) and some of it goes into doing work by expanding the ideal gas.
Thus, the temperature increase is smaller in the constant pressure case than in the constant volume case. This is equivalent to saying that the specific heat capacity at constant pressure is larger than the specific heat capacity at constant volume.
Answer: First law of thermodynamics $$\delta Q=\delta E+p\delta V  $$
$$\therefore\frac {\delta Q}{\delta T} = \frac{\delta E}{\delta T}+nR$$
As $p\delta V$ can be written as $nR\delta T$
When volume is constant $$\delta Q= \delta E $$
$$\therefore\frac {\delta Q}{\delta T} = \frac{\delta E}{\delta T} $$
$\frac {\delta Q}{n\delta T}$ is Molar heat capacity.
$$\therefore C_\textrm{constant pressure}=C_\textrm{constant volume} + R $$
Heat capacity at constant volume lower than heat capacity at constant pressure.
Answer: If you cannot understand, you are not alone; even teachers find difficulty to grab.  The difficulty of understanding is due to the rubbish ways of explanation in academic/ textbook. Let's see the actual concept.
Cv is heat capacity at constant volume.  Constant volume has no direct meaning in heat retaining capacity.  Constant volume indirectly means work done is prevented.  In this situation, all the heat, if added, is contained within the system volume.
On the other case, Cp is heat capacity at constant pressure. Constant Pressure is of no meaning in heat containing capacity. But the fact is: when heat is added, system pressure raises leading to expansion.  During expansion, some of energy is expelled i.e. transported to boundary/ periphery and resides over the boundary as potential energy between the system and neighbour/ surrounding.  Here, heat is kept in two locations - one) within volume, two) Over-periphery.
While Cv is referring capacity within volume, Cp is referring capacity within volume as well as on periphery.  Hence Cp is more than Cv.  Cv may be redefined as heat capacity within volume and Cp may be redefined as heat capacity within upto periphery.
Comment: Welcome on Physics SE. Please consider writing your post a bit more structured and with less personal judgements. Also, please see our help page for help in typesetting formulas.
Answer: i think ,heat energy is required to change the temperature of the gas as well as for the the expansion of the gas against external pressure hence,change in temperature at constant pressure ,therefore Cp>Cv
Comment: Don't add, `i think`; it reflects your ignorance of the matter and nothing else; if you're not sure, then don't post your view as an answer.


Why doesn't my government, and governments in general, provide useful statistics in digital format?

Question: I live in Sweden, but this applies to all other countries as well.
I have a general interest in, and fascination of, statistics and working with data in databases. By far the biggest obstacle has nothing to do with technically dealing with the database software, writing SQL queries, or designing databases. Rather, the #1 problem is:
Nobody wants to provide useful data!
I have spent a significant part of the last 20 years searching for databases/data files of all kinds. Time and time again, I end up at a "contact us for pricing" webpage, or a "Buy now for only $4,799!" text. Oddly, this does not just apply to commercial entities, but also authorities.
Even though the Swedish government has been talking about "open data" and "free information for all" for a very long time, the actual reality is that virtually none of that juicy data is available for you and I to grab and use. Instead, they have multiple layers of "red tape", requiring you to pay through the nose for any kind of access, and in many cases, you aren't even allowed to pay for it unless you run a major corporation with special ties to the government. It's really bizarre.
The data they do allow you to look at is meaningless/shallow statistics, rarely if ever provided in a format which can be reasonably parsed by a computer and fed into my database for further analysis. The so-called "open data for everyone" often consists of nothing more than a bunch of formatted PDFs, useless for my purposes.
I'm not interested in static columns showing how many new people were born in 2020. I want a list of those people, with their names, genders, race, blood type, etc.
I realize that all data cannot be open without heavy abuse inevitably resulting from it. However, at least the Swedish government has this idea of "public records", where you are theoretically allowed to request all kinds of data. The problem is that they only allow you to do this in person, over phone or via e-mail, and you have to do it manually and only request at most three (3) "units" each time. In practice, this makes it useless.
If this information is allegedly "public", why are they so unwilling to actually make it available? I could send an e-mail to a Swedish government entity right now, requesting all kinds of information (including their full social security number) for a given person, and they will respond within 24 hours with it, no questions asked. I've done it many times. However, if I ask them for a Swedish_people.csv file with every person registered in Sweden and the same information I requested manually for one or up to three persons, they will refuse.
Major corporations are able to pay a lot of money to get access to their government APIs, but it costs a fortune and they wouldn't let me buy access to it even if I had the money (because I don't run a major company).
It doesn't make any sense to me. I wonder why they have these double standards, and how they can possibly charge money for "public" records.
A dream of mine would be to be able to do:
<code>SELECT name, email_address, physical_address, passport_photo FROM people WHERE current_city = $1 AND gender = $2 AND age >= $3 AND age <= $4 AND civil_status = $5 ORDER BY distance_from_me DESC;
</code>
Of course, this is completely unrealistic, but you get the idea. I wish to have actual, curated records from (semi) trusted sources rather than having to play with the few, measly databases which are freely available to the public at no charge.
A perfect example of something very basic would be the telephone book. Back in the day, they sent out a complete book of every single person's name, telephone number and address to every household in the entire country. This was standard practice all over the world, I believe. A digital version of that would be a .csv file which I could just download from a government website at a static URL, always kept updated. Nope. Nothing like that. I'm forced to use these third-party, commercial websites where I get to enter individual people's names and send this information to the company in question. They are paying the government a lot of money to get this information, even though it could be made available for virtually no cost at all.
Why, since they used to provide this information in physical form, is it now unthinkable in the digital age?
Comment: it's a little bit of effort, but with today's technologies like CI/CD, git, free hosting, etc, it's possible to create pipelines to read official but difficult open data and re-factor it as your swedish_people.csv. It's a pretty good project for a hackathon
Answer: It would be easy if data was available. You are paid to clean it. If you provide your own clean database then people will pay for it if its important.
The cleaning is left up to private  data vendors. Gov only provides raw data. It's better because less errors. No reason for them to add complexity.


Are people really punished for their bad deeds?

Question: In this world people commit many bad deeds in their day to day life. Some on extreme level, but still those people live their life happily. There are many historical examples of such people for instance Aurangzeb etc. So do such people get punished for their bad deeds? Now the common answer would be that there is hell and heaven after life or they are punished in their next birth, but I didn't get this concept. If a person is not punished in his present life, how can he be punished in his next life? Puranas have a lot of references to hell and heaven but what does Vedas, Upanishads, Bhagavad Gita or epics or Agamas have to say about it?
Comment: You could limit the number of scriptues.Otherwise becoming too broad.
Comment: Related: https://hinduism.stackexchange.com/questions/8848/if-karma-works-why-are-so-many-evil-or-corrupted-people-successful/33090#33090 My answer there is also applicable here
Comment: If it's difficult to understand that people have to suffer for their bad deeds in the next life, then this question may be of some help: Why people have to suffer in this life, is there some reason for their suffering or they just suffer because of no karmic reason?
Comment: no. everything you do carries along with it a slew of other things. those add-alongs are what causes the bad things following bad deeds. there is no cosmic retribution. Now, that said. if you do bad things that generally carries ill-will from those around you which is part of the add-alongs. so in a way that is the punishment for bad things also. but there is no moral judgment from brahman.
Answer: The misdeeds are like the "act of sowing seeds in the soil".
Just like we don't get fruits immediately after sowing a seed, in a similar manner, the fruits of misdeeds are not received immediately. It takes some time before the fruits are received.
In KulArnava Tantram Chapter 1, Lord Shiva says:

Iha yat kriyate karma tat paratropabhujyate | Siktamulasya
  virkshasya phalam shAkhAsu drisyate || (verse 53)
Whatever deeds that are done here (in this world - Ihaloka) create
  fruits and that are to be reaped. The roots of the trees are watered
  and the fruits are seen in the branches.

So, without doubt the Jiva has to face the consequences of it's good or bad deeds.

DAridrya-dukkha-rogAshcha vandhana-vyAsanAni cha |
  AtmAparAdha-vrikshasya phalAn-yetAni dehinAm || (Verse 54)
Poverty, misery, diseases, bondage and the bad habits -- these all are
   the fruits of the tree (Atma-Aparadha Vriksha) which is the
  manifestation of the Jiva's misdeeds.

So, the misdeeds are like seeds, which grow up, in time, into trees that are ready to bear fruits. And, the fruits of the bad deeds are those miseries mentioned above. But it takes time for the seeds to grow into fruit-bearing trees. Mostly, fruits of karmas are received in the next lives.
Therefore, Aurangazeb or any other miscreants must have been punished for their bad deeds.
In Hinduism, the king should punish for the sins that are traceable i.e. which are openly done (like theft, murder etc etc). And, Yama punishes for the secret sins and the rest.

3 The elder disciplines those who are self-controlled and the king
  disciplines those who are wicked, whereas Yama, son of Vivasvat,
  disciplines those who commit sins secretly
Vashishta Smriti 20.3

Auragazeb himself was a king. So, there was none (except other kings and rulers) who was able to punish him. So, from the perspective of Hinduism, all his bad karmas must have been duly judged by Yama in the afterlife.


ms sql differential backup size jumps

Question: We are doing a full backup once a week and a daily diff between that.  The total db is 80Gb, the diffs start out under 1Gb, then gradually grow to approximately 3-5Gb which is ok, but then all of a sudden jump to 40Gb almost every week.  Why would this happen?  How do I investigate?  I'm reasonably sure that the actual db usage is uniform w/o spikes.
Answer: Perhaps you've got a maintenance job - such as reindexing - that occurs once a week - that would cause a massive jump in diff backup file size. Or perhaps it's a once-a-week application job that imports or changes data?
If you're also taking regular transaction log backups (say once an hour), if you look at the file size of those backup files it may give you a clue as well as to when the change activity is.
Answer: The size of your differential backup is dependent upon the amount of data that has changed since the last full backup.
You should be able to identify which day there is a spike in the size of the backup. Start by seeing if there is a trend, perhaps it is the same day every week, for example. Then look to see if you have any maintenance jobs that are running on those days.
It could be the case that perhaps you do not have jobs running at that time, but there could be a piece of application code that decides to perform some maintenance without your knowledge.
If you are able to isolate the particular day that you see the spike you may want to use Adam Machanic's free tool sp_WhoIsActive http://whoisactive.com/, and see this blog post from Kendra Little on how to store the results http://www.littlekendra.com/2011/02/01/whoisactive/
Answer: Differential backups save the extents that were changed since the last full backup. Any update/insert/delete statements to your DB will have extents that change. Most of the time, if the DB size is the same, then the extents changed will be due to update statements run on the DB.
Another event to look out for are maintenance tasks on the DB like index rebuilds.

ms sql differential backup size jumps


Disable bold fonts on Google search results

Question: Today Google started to display search results in a bold font. How can I bring back the normal way in which search results were displayed?
Comment: This is something Google is experimenting with, refer http://www.texient.com/2014/03/google-search-result-layout-big-font-changes.html
Comment: Thanks @SunilManheri.Today my search results came back to the normal way it used to be.
Answer: The titles of the search results aren't bold; instead, the font size is now 18px rather than 16px like it was previously.
Also, this change doesn't affect only Google Chrome. I use Firefox and I see the change too.
Lastly, the change seems to come and go. I see it one day but not the next. As Sunil Manheri commented above, Google seems to be experimenting with changes to their search engine results pages (SERPs).
I hate the new font size and much prefer 16px. I added the following CSS rule to my user stylesheet (userContent.css in my Firefox profile) to force Google's SERP titles to be 16px:
<code>body#gsr h3.r {
  font-size: 16px !important;
}
</code>
Google recently removed support for user stylesheets from Chrome (in an effort to dumb down their browser even more than it already is). Fortunately for Chrome users (definitely not me), user styles can be added to Chrome using the Stylish extension.
Answer: For those who are looking for a cross-browser solution, I have written a small bookmarklet, which will reduce the font size as well as to add underline to hyperlinks:

See the blog I posted on the topic for further information: http://techawakening.org/?p=2800
Answer: Google switched to a larger size in their font. (I agree Arial, or whatever it is, is ugly at that size) I solved the problem by setting that page to 90% zoom.  (Chrome browser.) Thankfully, the zoom feature applies only to specific pages, and remembers.
Answer: how to bold text in description google search?
Bolding, underlining, bullets all help to structure information in an educational manner (see all the texts books you read in college). Google likes it when it thinks you are providing educational relevant material. If a word is in your link, in your title a bolded header and underlined in the body google know this is an important topic on your page as well as the reade
Comment: How does this answer the question?
Answer: I using meta description : I bold ❺⓿% and ❶⓿⓿
View:
https://www.google.com/search?newwindow=1&q=mua+ban+nah+dat&oq=mua+ban+nah+dat&gs_l=serp.3..0i10j0i22i30l9.3348.4965.0.5188.8.131.52.0.0.0.152.1324.12j3.15.0....0...1c.1.38.serp..1.14.1185.QAQjB4ETEi0


Why is the Ethernet Connection Symmetric?

Question: I know that cable connection (DSL) is asymmetric, there is a certain bandwidth on the channel, and for a better user experience, they allocate a bigger portion to the downstream. I suppose Ethernet cables have a certain bandwidth as well, or fiber-optic cables.. Why are they symmetric?
Comment: The DSL allocation is purely arbitrary and mostly assymetric to only require cheaper hardware at the end user, and because that is the most common use case. You can always get symmetric DSL.
Answer: The very first Ethernet standards were designed for using a single, shared coax wire. There's no benefit in making the connection asymmetric in any way.
Additionally, network nodes are generally viewed as equal peers from the technology design perspective (in contrast to specific network design). There's simply no motive in making a general-purpose network technology not symmetric.
ADSL had a completely different design goal - it was intended as a high-speed distribution network link using legacy cabling with limited bandwidth. There are clear uplink/downlink roles and it's no general-purpose network link. Intended as a consumer connection, more of the available bandwidth is allocated to the downlink than to the uplink, as fits the roles.
The roles in xDSL have changed somewhat over time and VDSL 2 can actually adapt to that, featuring different downlink/uplink bandwidth allocations.
Answer: Q: Why is ethernet symmetric (when compared to ADSL's asymmetry).

A: This is best explained by looking the technical reason for ADSL's asymmetry.
Quoting directly from wikipedia:

There are both technical and marketing reasons why ADSL is in many places the most common type offered to home users. On the technical side, there is likely to be more crosstalk from other circuits at the DSLAM end (where the wires from many local loops are close to each other) than at the customer premises. Thus the upload signal is weakest at the noisiest part of the local loop, while the download signal is strongest at the noisiest part of the local loop. It therefore makes technical sense to have the DSLAM transmit at a higher bit rate than does the modem on the customer end. Since the typical home user in fact does prefer a higher download speed, the telephone companies chose to make a virtue out of necessity, hence ADSL.

In short, ADSL's asymmetry reduces cross-talk at the DSLAM, where a large bundle of cables terminate close together.  If the designers choose a faster customer upload speed, they would need a stronger signal to increase signal-to-noise ratio (thus increasing cross-talk at the DSLAM).
Ethernet was designed for a completely different purpose and doesn't need the asymmetry.  Ethernet isn't restricted to a residential market with legacy cabling; furthermore, asymmetry in ethernet would needlessly complicate many ethernet designs.
Answer: Ethernet is a local area network technology, and it was designed with no assumption that traffic will be higher in one direction than the other.
It was developed long before the web or Internet was available.
Answer: The cabling for ADSL uses telephone grade cabling and upstream and downstream traffic share the same copper pair.  As there is limited bandwidth, the designers chose to give the downstream more capacity to make more efficient use of the bandwidth, something that fits the usage patterns of home users.  ADSL was designed for a specific use case – to connect home users to the Internet.
Ethernet on the other hand was designed to be a universal standard to support many use cases.  The device on the end of an Ethernet cable could be a PC, server or even a device running peer-to-peer software.  You can't make any assumption as to whether the device would need more sending or receiving capacity, so providing symmetric capacity makes Ethernet a far more universal standard.
Early Ethernet was half-duplex.  Not setting limits on the send and receive bandwidth made it a lot more flexible.  Devices could use as much send or receive bandwidth as there was available.  It also operated on a shared multi-access cable, setting upstream and downstream limits in this case doesn't make sense.  Modern Ethernet is now full duplex, so the physical medium itself provides an efficient symmetric data path without the overhead and complexity of CSMA/CD.
Comment: I beg to disagree with the half-duplex statement - ADSL uses frequency-division multiplexing and is generally full-duplex capable.
Comment: Recheck G.922 - it's full duplex. You could call TDM half-duplex but not FDM. Completely different technology (hybrids and echo compensation) but each 1000BASE-T lane and 100BASE-T1 use single pairs as well and are undoubtedly full duplex.
Comment: I was referring to the same physical cable being shared for upstream and downstream, perhaps half-duplex isn't the correct term in this case so reworded
Comment: The medium is half-duplex, it is a shared bus, only 1 pair of wires.  I see your point though


What is the "3 foot law" and which US states have it?

Question: Some states seem to have something called the 3 foot law to keep cars away from cyclists.  Why 3 feet?  Which states in the USA have it?
Comment: @Daenyth "state" is often short for "nation-state", so there are states within states in many places. For example, I live in the state of New South Wales in the state of Australia. But only one country still uses imperial units, so in this case the OP is only asking about the empire.
Comment: On top of the states that have it, there are also communities (well, at least one) that have it even if the state does not. I live in Columbia, Missouri and we passed a three foot law a couple years ago even though the state of Missouri doesn't have one.
Comment: A 3 foot law [is currently on Gov. Jerry Brown's desk](http://givemethree.squarespace.com/) in California. In 2011 he [vetoed a similar law](http://sf.streetsblog.org/2011/10/07/ca-bike-coalition-refutes-chps-claims-around-3-foot-passing-law/).
Comment: The CA 3 Foot Law just passed! Bradford's bill, AB1371 will go into effect Sept. 16, 2014. news: http://www.mercurynews.com/california/ci_24159945/cyclists-will-get-3-foot-buffer-under-new legal info: http://leginfo.legislature.ca.gov/faces/billNavClient.xhtml?bill_id=201320140AB1371
Answer: The 3 foot law is an example of a law that exists mostly to create awareness rather than having some direct practical function.
This law is rarely enforced by itself. Can anyone cite an instance where a motorist was ticketed for passing in under three feet (and not ticketed for anything else)? The 3-foot law is, AFAIK, typically enforced as a supplement to some other violation such as failure to yield or reckless driving.
But more than anything else, the intent is to create some level of awareness in motorists about how to deal with cyclists. If motorists know it is a law, most will make an effort to abide by the law.
A quick Google search reveals that, as of 2023, 39 states in the USA have this law.

Year
Count of States

2023
39

2019
27

2012
20

It seems to me that in the last 10 years or so, motorists have been getting much better than in the past about getting along with bikes. It could be the marked lanes/signage, or perhaps things like the 3-foot law, but I have noticed a LOT LESS "entitlement-to-the-road" behavior from motorists than in the 1990's and earlier.
Answer: Three feet just seems (to legislators) like a reasonable number (it's 1 meter in the UK and I think most of Europe).  And I know it's the law in Minnesota.  Don't know about any other states.
Would a different number make more sense?  Probably not.  Less would be out-and-out dangerous, and more would create the situation where the bike (in theory) blocks traffic in too many cases (and hence would be ignored even more than the current law).
Comment: Just checked wikipedia, in Germany the "Sicherheitsabstand" (safety distance) is 1.5m (5 feet) to bikes and motorbikes. But only 1m to cars.
Comment: Illinois has a 3 foot law as well. 3 feet is a little longer than an average arm length, so it's easy to gauge and seems like a logical mental barrier. Can you touch the car? No? Ok, that's "safe".
Comment: Germany has something like this, too. I am not sure if it is a recommendation or a law, but most people abide it anyway.
Comment: In the UK it's "at least as much room as you would when overtaking a car".
Comment: In Ireland 1.5 meters is also recommended on the Road Safety adverts, but it isn't a law as far as I know. http://www.youtube.com/watch?v=JB9d-c-M7D0
Comment: @Baarn No. People definitely do not abide by the german rule. Never. The german rule requires 1.5m, and cars will routinely overtake bikers with less than 0.5m. The only way to get at least 1m between yourself and overtaking cars, is to take your lane. If you squeeze to the right border, cars will squeeze next to you.
Answer: Pennsylvania's got a new four-foot law.  It was recently enforced after an attempted hit-and-run in Bethlehem, PA (http://www.youtube.com/watch?v=b7AVC1YCcO0).  (I should clarify that it was a hit-and-attempted-run, as other motorists pinned the driver in to prevent him from running).
Answer: France has such a law (1 metre in cities, 1.5 metres in the country). That safety margin is also applicable to passing pedestrians and animals.
France (and, "much of Europe") also has a "strict liability law" (ref and ref), IOW if there's an accident then it's up to the car-driver to prove that they're not negligent.
Answer: Five feet seems to be a popular variant of the 3-feet law.  I suspect that's because if you tell people five, maybe they will give three.  But five has the benefit of making it cleaer that the car needs to partially cross over to the other lane instead of trying to squeeze by without crossing the line.
Comment: However, the law in at least some states explicitly says that if there is sufficient lane width the automobile need not cross out of its lane.
Answer: The 3-Foot Law passed a few years back has brought much more awareness with motorists and cyclists alike here in CA.  I have noticed greater compliance here in Midtown Sacramento where one motorist will yield to a bicyclist and whoever is behind them in the following car will follow suit.  How other cities/neighborhoods have reacted is beyond my reach, since I only ride in Sacramento, however, my best guess would be motorists are much more aware of the need to "share the road" there as well.  It should be noted when the law passed, there was significant backlash from the "entitled motorists" among us.  This lasted for at least a year.  Gradually, however, at least here in Midtown, I've witnessed improvement in the relationship between cyclists and motorists alike.  A reduction in the speed of both is critical for this to work, and that has happened with the advent of protected bike lanes, bicycling education classes sponsored by the City of Sacramento and  Sacramento Area Bicycle Advocates (SABA), and a better appreciation of the role of bicyclists in the area.  We're hopeful for continued change.


Should I mount the procfs on a FreeBSD server?

Question: The procfs manpage states that procfs is required for the complete operation of programs such as ps and w. I want to mount it but wonder if there are any security implications of doing this.
Answer: In my experience in FreeBSD you'll only need to use procfs when you use Linux binary application.
You can check this article on FreeBSD Handbook , hope it helps.
Comment: `ps -e` requires procfs
Answer: This is basically standard in the linux world..
I would assume for that reason, you have not to worry about security implications for this particular question..
What do you expect a security implication could be???
/proc maintains and shows simply an open heart to the kernel and process's
Note: i just "quickly" checked online ( yes i have the internet :P ), and found 2 security problems from 2000 & 2005 for BSD variants... However im sure they are fixed


Is constant air pressure maintained inside the fuselage?

Question: I just heard it somewhere but I'm not sure about it.   If it is, then why don't they build airtight fuselages?
Comment: It would be interesting to have answers that differentiate between passenger aircraft, cargo, and military.
Answer: For the purposes of air pressure inside aircraft, they are broken down into two broad categories:

Unpressurized - These aircraft are typically piston powered and can't go very high, so do not even attempt to regulate the air pressure inside the fuselage.
Pressurized - These aircraft do maintain pressurization in the fuselage, but it isn't constant beyond a certain point.

The category determines the answer to your question:
Unpressurized Aircraft
Unpressurized aircraft are not built air-tight for a couple of reasons:

It is very hard to make something as large as an airplane truly air-tight, and keep it that way.  Over time, seals will start to leak, fittings will loosen, etc.
The fuselage would have to be much stronger to withstand the pressure difference between the inside and the outside.  This would make them heavier and more expensive.
There isn't much need.  These airplanes don't fly high enough to really require a pressurized fuselage and a person can breathe more or less normally even though you aren't at sea level.  (Think of people that live on mountains.)

Pressurized Aircraft
Without going into the details of how an aircraft is pressurized (which isn't really relevant to your question), the air pressure inside the fuselage of a pressurized aircraft is usually maintained at sea level pressure up to a certain point.  However, the fuselage is designed to withstand a particular maximum differential air pressure, so in order to protect it (basically keep it from "popping" when the air pressure outside the airplane drops too low), the pressure is allowed to decrease when needed.
In typical jet airplanes, the pressure inside portions of the airplane (typically the passenger compartment, some of the cargo holds, and maybe an avionics bay) at cruising altitude is maintained at a pressure which corresponds to an outside air pressure at an altitude of about 5,000 - 8,000 feet (referred to as "cabin altitude"), depending on the cruising altitude and the design of the airplane.
Answer: Many aircraft are not pressurized and therefore not airtight. The occupants would suffocate, if nothing else, and most unpressurized aircraft do not regularly operate at altitudes requiring pressurization.
In the case of pressurized aircraft, it's actually necessary that the cabin is not airtight. They are, instead, nearly airtight and can withstand significant pressure differentials.
Cabin pressurization works by bleeding high-pressure air from the engines, which is then run through packs (heat exchangers and air cycle machines) to cool it. After conditioning, the air is fed into the cabin. This is what creates the lower cabin altitude relative to the outside atmosphere.
Because more air is constantly being added to the fuselage, a pressure outflow valve is required and it is constantly dumping air from inside the aircraft. In normal operations, it's automatically controlled, but can be manually overridden in emergency situations.
Comment: @DanPichelman: Early diesel subs had to surface regularly to refresh their air supply; modern nuclear boats (and possibly diesels) have [onboard plants that scrub CO2 and/or generate oxygen](http://en.wikipedia.org/wiki/Submarine#Life_support_systems). Minisubs, much like SCUBA divers, carry bottled air and presumably also use scrubbers. Aircraft that were genuinely airtight would need to carry a *lot* more equipment.
Comment: Great answer, but I'm not sure about suffocating.  People in submarines & mini subs don't seem to suffocate very often.
Comment: @egid nuclear subs can generate oxygen because the power plant does not use oxygen. Simply using conservation of energy, we can show that it is impossible for a diesel sub to generate enough electricity to generate oxygen. If fact, most diesel subs, don't run the engine under water, but use batteries to conserve oxygen.
Comment: I think you will find that virtually all diesel subs in operation today can operate their engines with the hulls submerged, as well as operate on battery power when submerged to a greater depth.  They use a snorkel device pioneered by the Germans in WWII.    This does not change the validity of your answer regarding nuclear subs, though.
Answer: Pressurized aircraft are not airtight, and neither are they constant pressure.  One key facet that would make being airtight impossible is the need to change pressure in the cabin.
To change pressure in the cabin, air is pumped in via the packs (covered in another answer), and air is let out via outflow valves.  The input is fairly constant flow and pressurization is modulated by how open/closed the outflow valve is.
Cabin pressure must change because the airframe has a maximum pressure differential between the cabin and outside (7.8 PSI in the EMB-145) and as you climb the pressure in the cabin must be reduced.  The cabin is generally 8000 ft pressure altitude at during cruise.  Subsequently the cabin pressure is increased to the landing airport during descent.
Accompanying these changes in pressure are temperature changes naturally occurring as result of the pressure change (see: ideal gas law).  You may notice this during descents in regional jets as they tend to get very warm as the cabin is compressed.
To regulate the temperature, you need air conditioning, and so you have packs and air cycle machines to deliver air at the proper temperature to the cabin.  Now that you have to provide air into the cabin, its not worth even thinking about CO2 scrubbers and O2 tanks, because the packs take care of that with fresh air.
That should cover airplanes not being airtight, why they aren't airtight and that the also are not constant pressure.
Answer: The answers so far have talked about the differences between pressurized and unpressurized airplanes, however to answer your question why they're not airtight:
The answer is two-fold, first as egid pointed out, the pressure differential would probably be too great for the hull to withstand.
Second, and in my opinion, more importantly, humans consume oxygen and output carbon dioxide (and water). Having your ship airtight, would cause everyone inside to slowly but surely suffocate from carbon dioxide poisoning and lack of oxygen as the little oxygen carried within the aircraft slowly gets breathed away. So you need to keep replacing that air, and the easiest way to do that is to let the old air out, and put new air in.
Edit
As Dan Pichelman points out, people in Subs aren't dropping like flies. True, they're not, but they are in fact also replacing the air. Almost. They're removing the CO2 (using Scrubbers) and adding Oxygen (from oxygen tanks). It would probably be possible to solve it this way for aircraft as well. The question remains whether it is feasible weight wise, and if it's easier to just pressurize the aircraft using bleed air and dump the old air overboard.
Comment: A 737-800 has (less than) 1.6 cubic meters of air per passenger (I assumed square cabin cross section, and used the full length of the aircraft). So let's say about 1500 liters/person, and we inhale about 8 liters/minute of 20% oxygen, and exhale 15% oxygen, if we didn't replace it with CO2, and simply discarded 2 liters of the air it'd last 13 hours with 0 oxygen left afterwards. I'm no physician, but I'd wager you'd die from CO2 poisoning long before that. It CAN probably be solved like with subs, but as in the answer, it's easier to just replace it.
Comment: @roe yeah, it's also almost certainly *lighter* to replace it, and it *definitely* requires less energy.
Comment: This is why people in submarines are constantly dying?
Comment: @Dan; well yes, if the oxygen tanks they carry along run out, they would most likely die. Airliners carry oxygen tanks as well, but only for the pilots in emergencies.
Comment: Sorry, snarky comment on my part - I'll remove in a minute.  My point is how long will it take to consume the O2 given the cabin volume?  If it takes 6 hours to reach dangerous CO2 levels in a plane with 3 hours of fuel...
Comment: I'll try to dig up some data, would be interesting to know.
Comment: Some submarines add oxygen from tanks, but many actually generate it through the electrolysis of water.
Comment: @egid; interesting, didn't know that. The first google hit said oxygen tanks.. :) What do they do with the hydrogen? Dump overboard?
Comment: @Dan as for why people die in subs,  Hollywood provides no end of material,  but concerning realism *nothing* can beat [Das Boot](http://en.m.wikipedia.org/wiki/Das_Boot).
Answer: In many General Aviation aircraft (small planes that don't go above approximately 12,000 ft.), the air pressure in the fuselage is the same as the outside air.
Most people have no difficulties at altitudes up to 12,000 ft, so there is no need to maintain a pressurized environment.
Specific rules state that unpressurized airplanes have supplemental oxygen available, depending on how high the plane is, for how long, and whether its flying during the day or night.


Can food swallowed when a person is upside down reach the stomach?

Question: If a person positions him/herself upside down and swallows food, will it reach the stomach against gravity? If so how?
Comment: http://en.wikipedia.org/wiki/Swallowing#Pharyngeal_phase, phase 11. So... yes
Answer: The eminent @JanDvorak has basically provided the full answer, but yes, it is possible.  You can easily try this yourself, just lean off a bed and swallow something (small) and see what happens.  Peristalsis in the esophagus is responsible for moving food down into the stomach.  The big proof of this is that astronauts can eat when in space, when weightless.  Their food is moved into the stomach just fine.
It's easier to do it upright (peristalsis + gravity) as opposed to upside down (peristalsis - gravity) but definitely quite possible.
Comment: It is _not_ a good idea to experiment with this just like that. A part of food can enter your larynx and bronchi and eventually lead to aspiration pneumonia.
Answer: Yes it is possible. As I myself have experienced it.I was doing a headstand when I tried it.It does take a lot of time but does reach the stomach.


How long is cooked hamburger able to sit in a crockpot?

Question: I came across a crockpot recipe for burritos. It calls for cooked hamburger (1 lb) as one of its ingredients and specifies that I should cook the mixture on low for 6-10 hours. Is this safe? Whenever I have cooked meat in the crockpot in the past I only use a high temperature and I take it off as soon as it is done so its not kept on 'stay warm'. Since the hamburger is already cooked this is not a question on will this cook it properly but more a question on is this safe and how long (max) can I leave hamburger on low?
Answer: food is safe so long as the Crockpot is on, and functioning correctly. The food will maintain a simmer as long as its on, which is too hot for bacteria.
Comment: I'm not a food safety expert by any means, but this is my understanding, and personal experience, as well.
Answer: I have a version of baked beans I make in a crock pot that cook for 24 hours on low. I've used a thermometer to verify that, once it comes up to temperature, it stays right at a simmer the entire time, which is above the 165F necessary to keep it "safe". I did the verification because of some of the horrified looks I got when I told people that these beans cook for 24 hours and the last 12 is when the changes happen that really make them good.
Basically, the main danger zone is 41F to 140F. If food sits in that range, it's dangerous, and your goal is to get it out of that range as quickly (within reason of course) as you can to maintain safety. If it's colder or warmer than that, you're safe. Unless your crock pot is broken, the low setting is definitely fine.
I would be more leery of the "Keep Warm" setting. That's probably just barely keeping food out of the danger zone, and if it's miscalibrated, it could be holding food right on the edge of the danger zone.
Answer: The hamburger meat itself is never going to burn in a crock-pot, and as long as there is a good enough seal and enough liquid, it shouldn't dry out. As long as the meat is in the bacteria-killing temperature range, I don't see why it couldn't stay there for 10 hours.


Raising hands when making dua in salah

Question: Does raising your hands after tashahud to make dua durin salah invalidate salah? I heard that doing so during salah is bidah.
Comment: Does this answer your question? [Ruling of raising hands in Du'a before Taslim](https://islam.stackexchange.com/questions/22960/ruling-of-raising-hands-in-dua-before-taslim)
Answer: Some scholars allow raising hands during the prayer for example during a du'a like that of al-Qunoot, but there's no backup for doing so during (or after) tashhahud and before salam.
So considering this bid'ah seems correct. As it was not mentioned that the prophet () raised his hands for du'a in this position. And it is important that acts of worship should be performed in the manner the prophet () showed us else applies:

He who did any act for which there is no sanction from our behalf, that is to be rejected (Sahih Muslim)

"If somebody innovates something which is not in harmony with the principles of our religion, that thing is rejected." (Sahih al-Bukhari)

Nevertheless the prophet said:

The Messenger of Allah (way peace be upon him) said: When any one of you utters tashahhud (in prayer) he must seek refuge with Allah from four (trials) and should thus say:" O Allah! I seek refuge with Thee from the torment of the Hell, from the torment of the grave, from the trial of life and death and from the evil of the trial of Masih al-Dajjal" (Antichrist). (Sahih Muslim 1; 2 and Sunan abi Dawod)

But whether doing so invalidates the prayer needs a further investigation as there are acts and happenings that invalidate the prayer which basically are:
In first place we need to know that is in conflict to the necessary conditions for a valid prayer would invalidate the prayer like:

losing the taharah.
praying without knowledge of the (correct) prayer time.
praying with no hidden 'awrah
praying in the wrong direction (intentionally)

As scholars differed about what is rukn or not of the prayer it is essential for each Muslim to know and apply these arakaan as if we left any of them our prayer would be invalid.
And furthermore scholars defined the following acts as invalidating the prayer:

Eating and/or drinking while praying (the scholars are in consensus on the matter and say if anybody has done so he must repeat his prayer).
Speaking while praying and this may apply to saying "oh", "ah" etc. expressing a feeling or whilst crying etc. (we may find some evidences for that in the sunnah like here and here) this also refers to any sound that could sounds like speech, which one could hold, while saying "hatshi" while sneezing when one has caught a cold doesn't fall in this category.
Moving too much (or too fast) for example if one is looking around himself while praying or changing his actual position by a long walk in manner that a neutral observer wouldn't think he is praying.
laughing while praying however there's a difference of opinion the majority says this applies to loud laughing (horselaugh) while the hanafis say that this kind of laughing would invalidate both prayer and taharah and quite laughing (which only oneself would hear or feel) would only invalidate the prayer.
of course if one changed his niyyah and ended the prayer this way (by having the intention to leave the prayer for example) the prayer is invalid.

We are not a fatwa site so I'm not giving you a fatwa whether what you did or do is invalidating the prayer, but you must be aware that it might be considered as a movement which may leave the impression that you are no more praying!

Raising hands when making dua in salah