0969: "Delta-P"

[Fire Brns]

Also anyone else picture roughly the second to last panel in this occurring in narnia?
http://xkcd.com/585/

[danix]

The mental image of Aslan with the Space Core is hilarious.

"Son of Adam"
"Space Adam?"

SPAAAAAACE!

Also, GLaDOS might get the White Witch by promising her ...

... cake.

On the whole Narnia series, the last book "Final Battle" actually ups the Christianity gospel up to 11. If you actually do get to finish that book, you do need some heavy-duty Phil Pullman deprogramming.

[Sinnombre]

Didn't they do exactly that in one of the World of Tiers books?
/extremely data sci-fi reference

[meat.paste]

This one went up on my wall. I've already had two people laugh out loud. Very nice comic.

[Orangutanlibrarian]

A few problems.
One) A=Q/(sqrt(2*g*d)) Gives A = 2.019m^2. that's about the size of a normal door, the wardrobe was huge. I'd say the area should be at least 4m^2.

2) Narnia is big, like a big air pocket. That anchor looks very small to defeat a world's worth of buoyancy.

iii) A water jet moving at 200m/s would very quickly scour away the wooden wardrobe. Make the wardrobe out of stainless steel and put a hydro generator in front, free energy!

[supersteve524]

What about the time speed differences between Narnia and our own world. We know that time flows much more quickly in Narnia than it does in our own world. There isn't a quantitative scale since the time scales seem to vary, but we can make estimates as to how the two timelines move during the time in question. In the Lion, the Witch, and the Wardrobe, the children are in Narnia for 27 years with no perceptible time lapse on earth. We can interpret that "no perceptible time lapse" to mean less than 1 minute at the outside. This makes the Narnia time/Earth Time (N/E) during the White Witch's reign to be about 14.2 million to 1.

27 Years x 365.24 days/year x 1440 minutes/day = 14,200,531 minutes that the children were in Narnia (in Narnia time)

That means that the ~400,000L/s water leaving earth, turns into just under 3 mL/s entering Narnia

and that impressive 200 m/s water jet is trickling out at a whole 14.1 µm/s

[Agus]

Also anyone else picture roughly the second to last panel in this occurring in narnia?
http://xkcd.com/585/

LOL that would make the Narnia movies actually pretty cool.

Does anyone have the image on the super hiper megasized resolution it came out at first? Could you send it to me? I'm planing a nice poster on my bedroom door.

[someahole]

One issue with this approach: Earth to Narnia time dilation is not taken into consideration. (Narnia must be perched on the event horizon of a super massive black hole, given the incredible disparity.)

I don't think there are any concrete figures but assuming 1 minute on Earth is equal to about 1 day in Narnia, that gushing water just looks like a trickle on their end.

Edit: I just remembered that the time dilation effect fluctuates a bit: In The Lion, the Witch, and the Wardrobe, the children live their entire lives in Narnia and make it home for dinner, no one noticing they were gone. In other books centuries pass in Narnia between visits that are only months apart on Earth. So maybe Narnia is in a highly elliptical orbit around a super massive black hole and so is Earth? A bit of a stretch, I know.

[Colin OOOD]

This comic reminds me of Iain M. Banks' novel Inversions, in that the main character doesn't actually make an appearance.

[edbennion]

Hydrodynamics humor FTW!

Fun Quiz: Kids, show your skills and estimate how long it would take to empty all the oceans! Remember, as you drain the ocean, d in Randall's equation will decrease. Rename d as h. Then:

dh/dt = -k sqrt(h)

You can assume water transports horizontally instantaneously so the oceans always have the same level everywhere. You can assume the area of the oceans is constant with depth. Use a value equal to the volume of the oceans divided by the initial value of h. Assume the ocean is fully drained when h = 1 m.

Bonus point: Does the assumption about ocean area cause your calculation to overestimate the time to drain the oceans, or underestimate it?

If you are beyond college freshman age, this quiz is not for you.

I got to thinking after my inital post that the flow rate would decrease as the depth decreases, so good catch.

[andyfrommk]

The strip reminds me when I was a kid I wondered, in the Warhammer 40,000 universe, what would happen if you threw a vortex grenade into a gas giant

[hokansoc]

One issue with this approach: Earth to Narnia time dilation is not taken into consideration. (Narnia must be perched on the event horizon of a super massive black hole, given the incredible disparity.)

I don't think there are any concrete figures but assuming 1 minute on Earth is equal to about 1 day in Narnia, that gushing water just looks like a trickle on their end.

If one day there is one minute here, then the flow rate would be decreased by 60*24 (number of minutes in a day).

Given that the stated flow rate is approx 400,000 l/s and the velocity of the jet is 200m/s, the narnian values would be

400,000/(60*24) = 278 l/s
200/(60*24) ~ .139 m/s

So it'd still be dumping 278 liters of water into narnia for every one of their seconds. So about the same as a small river / large creek.

[Icalasari]

One issue with this approach: Earth to Narnia time dilation is not taken into consideration. (Narnia must be perched on the event horizon of a super massive black hole, given the incredible disparity.)

I don't think there are any concrete figures but assuming 1 minute on Earth is equal to about 1 day in Narnia, that gushing water just looks like a trickle on their end.

I only have the knowledge of the first movie, but that seemed to say that decades of Narnia time was minutes of Earth time. Unless the books differ there?

[Grant10k]

One issue with this approach: Earth to Narnia time dilation is not taken into consideration. (Narnia must be perched on the event horizon of a super massive black hole, given the incredible disparity.)

I don't think there are any concrete figures but assuming 1 minute on Earth is equal to about 1 day in Narnia, that gushing water just looks like a trickle on their end.

When the kids went back from Narnia to Earth, would they have hit resistance due to a momentum disparity? Would they have suffered health effects due to their backs aging at ≈1440 times the rate of their font sides? Perhaps the wardrobe acts as sort time air lock (Time lock?) and time switches over on your way to the other side?

Problem: Raising ocean levels due to climate change...

Speaking of fairy tales: Global warming. (don't call it "climate change"... During the height of Roman power the sea level was a least 2 feet higher. ... after the Ice age ... sea level was 3 yards or 9 feet higher ... Really what we need to worry about is tree huggers ...

[HTH]

This reminds me of Doctor Who episode Logopolis, where instead of the wardrobe it was the TARDIS, and though they had planned to flood it with the Thames to flush out The Master, it instead landed on Cadogan Pier in Chelsea, which juts out into the Thames.

[Colin OOOD]

I wish people could get past books having Christian roots. Most of Western literature has one foot in Greek mythology, and what's the difference to an atheist or agnostic?

For me, the main difference is that no-one today is trying to get the ancient Greek creation myth taught in science lessons at schools - even as part of 'the controversy'.

[Red Hal]

... kids ... hit ... their backs ... 1440 times ... Perhaps the wardrobe acts ... on your ... side?

*

__________________________________________________________________
*Be careful with ellipses.

[someahole]

When the kids went back from Narnia to Earth, would they have hit resistance due to a momentum disparity? Would they have suffered health effects due to their backs aging at ≈1440 times the rate of their font sides? Perhaps the wardrobe acts as sort time air lock (Time lock?) and time switches over on your way to the other side?

They seem to get "lost" between the light post and wardrobe doors, which implies a pretty smooth temporal gradient.

The issue is complicated by the fact that their ages are preserved between the two worlds. They leave as children, grow to adults, and return as children. Maybe the wardrobe has a transporter pattern buffer, or is run by the Hypotheticals from Spin. If the Hypotheticals are running the thing you probably couldn't get water through it anyway.

[Username4242]

Couldn't have said it better myself.

[flying sheep]

i came for the religious battles, thus i am disappoint.

[Grant10k]

... kids ... hit ... their backs ... 1440 times ... Perhaps the wardrobe acts ... on your ... side?

*

Like my Mom always says, "Don't let the wardrobe hit you 1440 times on the way to an alternate universe".

[bludemos]

At first I thought it was a coffin... so it didn't really make any sense...

[Grinde]

Problem: Raising ocean levels due to climate change (Or impending Noah-esk flood, depending on how Christian you are).
Problem: White Witch.
Solution: Throw drain into ocean near the level we want our oceans to be. Retrieve drain when ocean reaches acceptable levels.

Speaking of fairy tales: Global warming. (don't call it "climate change" if you still want so say the sea is rising) During the height of Roman power the sea level was a least 2 feet higher. Almost immediately after the Ice age ended the sea level was 3 yards or 9 feet higher than it was today. Really what we need to worry about is tree huggers keeping us from having fun. (note: not written in a condescending tone)

To act like I really care: Narnian world was flat or something like that so the water would just flood off the edges draining our oceans near completely rather than drop our ocean a comfortable few feet.

Would you mind sharing where you got the historic sea level data? (Note - legitimate interest. I love data )

[Dinoguy1000]

One issue with this approach: Earth to Narnia time dilation is not taken into consideration. (Narnia must be perched on the event horizon of a super massive black hole, given the incredible disparity.)

I don't think there are any concrete figures but assuming 1 minute on Earth is equal to about 1 day in Narnia, that gushing water just looks like a trickle on their end.

Edit: I just remembered that the time dilation effect fluctuates a bit: In The Lion, the Witch, and the Wardrobe, the children live their entire lives in Narnia and make it home for dinner, no one noticing they were gone. In other books centuries pass in Narnia between visits that are only months apart on Earth. So maybe Narnia is in a highly elliptical orbit around a super massive black hole and so is Earth? A bit of a stretch, I know.

It becomes much easier to wrap your head around (or not >_> ) if you just assume that Earth and Narnia are located in two different universes, each with their own local timeflow. The wardrobe (and other portals between the worlds) then just becomes whatever place the universes happen to rub up against each other in the multiverse. This of course still doesn't really explain how progression of time between the two is "locked" (that is, while the speed at which time passes between them is variable, it still always seems to progress forward - you can't go from Earth to Narnia, for instance, and then back to Earth and end up here before you left).

Problem: Raising ocean levels due to climate change (Or impending Noah-esk flood, depending on how Christian you are).

No Christian I know (and, considering I'm a Christian myself, that's quite a few) believes there is any such impending Noah-esque flood; indeed, the Bible clearly states God's promise not to ever flood the entire Earth again after the Deluge.

[RyanW]

Unfortunately, the plan turns out to have been masterminded by Frank J. Zamboni & Co. in an attempt to drum up more business. After the 100-year winter freezes all the water, the Witch is forced to employ hundreds of thousands of Zambonis to maintain what has become the largest ice-skating rink in the world(s).

[fibonacci]

I assumed the "Space sphere" was a reference to the one from Flatland. But apparently there's one in Portal 2 as well.

[Grant10k]

Problem: Raising ocean levels due to climate change (Or impending Noah-esk flood, depending on how Christian you are).

No Christian I know (and, considering I'm a Christian myself, that's quite a few) believes there is any such impending Noah-esque flood; indeed, the Bible clearly states God's promise not to ever flood the entire Earth again after the Deluge.

Well of course. You are too Christian to believe that story, but a Netsilik Eskimo might believe that

A flood killed all animals and humans except for two Shaman, who survived in a boat. They copulated, and their offspring included the world's first women.
Balikci, Ansen. The Netsilik Eskimo, Natural History Press, New York, 1970.

That Noah-esque flood could very well happen again, from what I understand of the Netsilik Eskimo culture (Full Disclosure: My understanding consists entirely of the previous quoted sentence. I didn't even check the source.). Why would a Christian believe an Eskimo flood myth?

Oh you thought I ment that if you were Christian you would believe in another impending flood. I understand the confusion now.
[quick_jab]

Spoiler:

Christians know that there won't be another flood because rainbows exist. Rainbows wouldn't occur naturally otherwise.

[/quick_jab]

[AngelfishTitan]

One issue with this approach: XKCD Fora to Earth time dilation is not taken into consideration. By the time someone decides to write about temporal differences between Narnia and Earth, five other people will have done it without reading the thread. QED.

[Steve the Pocket]

I wish people could get past books having Christian roots. Most of Western literature has one foot in Greek mythology, and what's the difference to an atheist or agnostic?

For me, the main difference is that no-one today is trying to get the ancient Greek creation myth taught in science lessons at schools - even as part of 'the controversy'.

Or, probably more to the point, trying to use ancient Greece as a model for our moral values and enact laws to that effect.

[TimXCampbell]

... maybe Narnia is in a highly elliptical orbit around a super massive black hole and so is Earth? A bit of a stretch, I know.

A bit of a stretch? Is that a pun?

I loved this mash-up comic. It reminded me of the crazy inventions by Daedalus (David E.H. Jones) that used to appear in Nature magazine. (Compilation book reviewed here.)

P.S. Spaaaaaaaaaaace! (Sorry, I just couldn't resist. Many of you out there wanted to do it, too.)

[rhomboidal]

I can just imagine the priceless facial expressions on poor Mr. and Mrs. Beaver.

[dp2]

I wish people could get past books having Christian roots. Most of Western literature has one foot in Greek mythology, and what's the difference to an atheist or agnostic?

For me, the main difference is that no-one today is trying to get the ancient Greek creation myth taught in science lessons at schools - even as part of 'the controversy'.

Or, probably more to the point, trying to use ancient Greece as a model for our moral values and enact laws to that effect.

I don't see how that affects whether or not one can enjoy literature based on either belief system. I don't like the idea of Sharia law, and some people want that, but I'm not going to duck Islamic literature because of that.

[philsov]

i came for the religious battles, thus i am disappoint.

I came for a joke explanation. Hell, I am disappoint.

Can someone aid the narnia illeterate? The kids dropped an oceanic anchor onto the white witch or something?

[Username4242]

In short, stepping through the wardrobe transports them into Narnia.

[DijiDori]

Is the time dilation even an issue? Assuming the portal to Narnia acts like Portal portals, the water will still have the same momentum when it passes through, right?

Everyone also seems to be forgetting that the portals are magic to some degree... The kids live their whole lives in Narnia then come back AS KIDS...

[Eebster the Great]

Would you mind sharing where you got the historic sea level data? (Note - legitimate interest. I love data )

There is an 82.3% chance it will be some spurious measurement of one coast that fails to take into account land rise and fall.

Problem: Raising ocean levels due to climate change (Or impending Noah-esk flood, depending on how Christian you are).

No Christian I know (and, considering I'm a Christian myself, that's quite a few) believes there is any such impending Noah-esque flood; indeed, the Bible clearly states God's promise not to ever flood the entire Earth again after the Deluge.

Well according to some dude named John it will rain fire, and there will be lakes of fire, so I suppose that means there will be a flood of sorts.

I assumed the "Space sphere" was a reference to the one from Flatland. But apparently there's one in Portal 2 as well.

In Flatland it was referred to as "Spaceland."

[cream wobbly]

Is it worth reading or watching?

Myself being a Christian, I can say that it was very worth reading. The recent movies also do a decent job. I can see how a non-Christian may not like it due to the Christian nature, but imagine that it is still quite entertaining.

For myself, it's the suggestive nature of a fawn (of whose mythology Lewis simply could not have been ignorant) inviting a young female child to his lair which puts it on a par with the Russian and German stories for scaring children. Disney has made a few of them into films.

Every time I hear "Narnia" or "Aslan" or any of the myriad other baseless names, I'm put in mind of the tongue-lashing Tolkien meted out to Lewis.

[nowhereman]

With the loss of gravity from free-falling and the slowing down of time dues to it being Narnia, it would pretty much be like Inception.

I sat down and did the math involved in this one. The equation left us is incomplete due the the fact that time runs faster there and slower here. From my memory (as shoddy as that is) I think it took 18 years of Narnia time to equal 30 seconds of Earth time. Calculating this out, Earth time is about 5.433 X 10^-8 times Narnia time. So factoring this into the equation the actual flow rate is 0.0217 L/sec. This would be the equivalent of a bad leak in our garden. So no doubt the evil white witch will be inconvenienced by this. Now here is a more interesting question... what happens if the white witch, in order to save her Rudabegas, decided to solve the flooding issue by plugging the hole? Anyone familiar with the effects of severe time effects know how forces like pressure work in boundaries?

[gfauxpas]

Shouldn't "water jet velocity" be "water jet speed"?

[another_oliver]

Reminds me of "On a silver platter" with Scrooge McDuck. However, Scrooge was quite far off when comparing the possible water flow to "the main sluice gate at Hoover Dam", which allows up to 11.000 m³/s according to WP - Randall's formula would put it at about 180 m³/s. Not to mention that even at 11.000 m³/s it should be difficult to drown Mt. Vesuvius under hundred feet of water.

Btw. the edginess of placing a "coin cleaning" system in Scrooges money bin only dawned on me many years after reading the comic...