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February 6

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Beautiful sunsets

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The sunsets in the San Francisco Bay Area over the last few months have been beautiful. Too beautiful. I don't think they were this nice in past years. Is there more particulate matter in the air right now for some reason? It's not listed as one of the consequences of the April 2010 Eyjafjallajökull eruption... -- BenRG (talk) 02:06, 6 February 2011 (UTC)[reply]

This article, from Apr 23, 2010, explains that Eyjafjallajökull had not (by that date, anyway) put enough particulate matter into the stratosphere to have much of a lasting effect on sunsets. WikiDao 02:18, 6 February 2011 (UTC)[reply]
This summary of emissions in California ranks them by source and county using data for 2005. Cuddlyable3 (talk) 03:14, 6 February 2011 (UTC)[reply]
The small volcanic ash particles in the stratosphere do not have a lot of "mass". There are some eruptions on the Pacific ring of fire. --Chris.urs-o (talk) 15:01, 6 February 2011 (UTC)[reply]
Many eruptions have occurred worldwide since the Icelandic eruption. See list of currently erupting volcanoes. ~AH1(TCU) 18:28, 6 February 2011 (UTC)[reply]

I think this is a result of the fact that we are currently experiencing the strongest La Niña in over ten years, and since around Jan 5 it has been very dry. Dry air tends to give better sunsets than moist air. I don't think the sunsets were so nice back in November and December, when it was rainy as hell. Looie496 (talk) 18:47, 6 February 2011 (UTC)[reply]

Well, yes, rain would rinse particulate matter out of the air. PЄTЄRS J VTALK 19:00, 6 February 2011 (UTC)[reply]
Oh, that makes sense. I don't know why I didn't think of that. -- BenRG (talk) 00:32, 7 February 2011 (UTC)[reply]

Reducing noise pollution

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Hi, I want to know Is it possible to make a device which will generate sound waves which will counter the sound waves generated in real enviornment. My Idea about this device is that ..... It will detect the frequency of all sound waves around it and simultaniously it will generate counter sound waves which will destroy the real sound wave ..... and our enviorment will be free of noise pollution.. —Preceding unsigned comment added by 220.225.96.217 (talk) 05:03, 6 February 2011 (UTC)[reply]

I don't think it's quite that easy. See our article Active noise control. Mitch Ames (talk) 05:08, 6 February 2011 (UTC)[reply]
(edit conflict)See Active noise control. If the region in which you are trying to cancel the noise is small (like the space between headphones and your ears) OR if the noise you are trying to cancel is relatively predictable and easily modeled, like a car engine, then technology is already on the market and in consumer products right now. Active noise control is availible in Noise-cancelling headphones you can wear. And some high-end luxury autos use active noise control to minimize the sound of the engine noise and road noise inside the cab of the car. The problem is that you can't design a noise control system for a big space where the sources of the noise and the people are all moving around. The thing about the inside of cars, and the inside of headphones, is that its a small environment to model and its very predictable. People sit in the same place, roughly, inside a car, and the space inside the headphones is really easy to design for. If your thinking of creating a giant noise-cancellation system which would, say, cover your entire house and yard, so that anywhere you were standing in your house would be noise free, its just too complicated to design such a system. The noise cancellation system needs to know where you are, so it can design the correct countrer-noise to broadcast. If you move in the soundspace, the exact anti-noise needed is going to change drasticly. You need a system that follows you around and hears what you hear, hence the headphones. --Jayron32 05:13, 6 February 2011 (UTC)[reply]
Another problem with large-scale noise cancellation is that because energy is conserved, canceling the noise in one area necessarily means having MORE noise somewhere else. If you make your house and yard noise-free, the neighbor might object to having an interference maximum inside his house. --99.237.234.245 (talk) 05:58, 6 February 2011 (UTC)[reply]
No, that's not necessarily so. The energy needed to create noise cancelation is provided the same way that your lightbulbs light. It doesn't necessarily hold that you have to create more noise somewhere else in order to cancel noise. Total energy is conserved, not total noise! --Jayron32 06:03, 6 February 2011 (UTC)[reply]
It doesn't matter how the sound is created in the first place. Once the noise-cancellation sound is created, it has sound energy; the noise that it's meant to cancel also has sound energy. That energy can't simply disappear after the two waves interfere, so if the sound has 0 amplitude in one area, it must have a non-zero amplitude elsewhere. For the same reason, it's not possible to have minima without maxima in a double-slit experiment, or to make the water come to a standstill by throwing pebbles to cancel an existing water wave. --99.237.234.245 (talk) 06:58, 6 February 2011 (UTC)[reply]
I agree 99.237.234.245. However as a practical solution you can baffle the anti-sound, and absorb the energy without bothering the neighbors. Ariel. (talk) 09:45, 6 February 2011 (UTC)[reply]
Yeah, but then you should also be baffling the original noise at the same barrier, no? Wnt (talk) 15:50, 6 February 2011 (UTC)[reply]
Nah, I don't think think Ariel means to insert a baffle barrier between the noise source and the hearer to be protected. Ariel is talking about reducing the added sound contribution outside the protected zone. Another improvement is to radiate the anti-sound at low level from a phased array of speakers that focus maximum power only at the protected hearer.Cuddlyable3 (talk) 18:10, 6 February 2011 (UTC)[reply]
Are you talking about white noise? ~AH1(TCU) 18:27, 6 February 2011 (UTC)[reply]
He's still talking about noise cancellation, whic is distinct from white noise. Someguy1221 (talk) 19:39, 6 February 2011 (UTC)[reply]
I would still agree with Wnt. If you are adding a baffle to outskirts of the protected zone, it seems likely this be between the hearer and the noise your'e trying to cancel. This would therefore also help stop incoming noise anyway. It's probably not perfect, but that would likely apply to the anti-noise as well in other words you're still making more noise for others even if you're partially baffling it. To put it a different the baffle either works or it doesn't. If it does then why the noise cancellation? If it doesn't then you're still arguably being a nuisance to others. I guess if the source of your anti-noise is from the baffles pointed towards the hearer and the protected zone is quite large your contribution may be minimal compared to the effectiveness of the baffle itself in stopping incoming noise (in other words the baffle may be better at stopping your anti-noise getting out then in stopping other noise coming in) but I'm not that sure, perhaps someone who better understands the physics of baffles and noise can explain? The exception would be if you're trying to cancel noise within the protected zone but as I understood the original premise, the idea was to create a protected zone from external noises like cars, lawn mowers, leaf blowers whatever. If the noise is within the protected zone, tell your partner/flatmate/child/parent/whatever to tone down the noise may work. Nil Einne (talk) 20:40, 6 February 2011 (UTC)[reply]
 noise ---> (protection) <--- anti-noise ---> (baffle) [otherwise extra noise would go here]
Ariel. (talk) 21:52, 6 February 2011 (UTC)[reply]
Yes that's what I mentioned in the late part of my discussion. My understanding is it wasn't really what the OP was thinking about, but perhaps I'm mistaken. Nil Einne (talk) 08:17, 7 February 2011 (UTC)[reply]
That diagram might look plausible, but move "(protection)" half a wavelength and the "noise" and "anti-noise" now add to one another. That's why I was assuming the layout was noise - anti-noise - (protection). Also of course the reality is three dimensional, and spheres don't meet up as nicely as line segments. Wnt (talk) 17:09, 7 February 2011 (UTC)[reply]

Gases

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A mono atomic gas and a diatomic gas are initially at same temperature and pressure, which are later compressed adiabatically to half their initial volumes. Then which gas has higher temperature? According to thermodynamics TV^(gamma-1) is constant, so that temperature of mono atomic gas is higher. But if we consider like, as attractive forces in diatomic gas are more due to more vander-waal forces of attraction so that, more energy is released and then Potential energy increases and due to which Kinetic energy increase, thus increasing temperature. So, what is the mistake in the latter reasoning? — Preceding unsigned comment added by Krishnashyam1994 (talkcontribs) 09:19, 6 February 2011 (UTC)[reply]

In a gas, the molecules spend most of the time so far from each other that there's no forces acting. Exactly which forces act during collisions is not thermodynamically important -- only what comes out of the collision is. The diatomic gas is different because its molecules can store energy in rotational and vibrational modes that do not show up in the kinetic energy of the entire molecule, and this internal energy mixes with the kinetic when collisions happen. There are no such hidden energies in the atoms of a monatomic gass. Therefore, when you add some energy to the gas (by doing mechanical work to compress it), the monatomic gas has to use all of the extra energy to make the molecules move faster (= increased temperature), whereas a diatomic gas can store some of it internally and only uses some of it for kinetic energy (= less increased temperature). –Henning Makholm (talk) 09:43, 6 February 2011 (UTC)[reply]

Specific heats

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What will be the Cv(Specific heat at const. volume) for triatomic linear and non-linear molecules? i.e., what will be the contribution of rotational and translational freedoms? but for both, translational freedoms are 3R/2 — Preceding unsigned comment added by Krishnashyam1994 (talkcontribs) 09:24, 6 February 2011 (UTC)[reply]

You first need to compute the number of degrees of freedom for the vibrational modes. You can do this as follows. A particle considered as a point mass has 3 translational degrees of freedom. A bound state of 3 particles will have 3 degrees of freedom for each particle, so there will be 9 degrees of freedom in total. You can then decompose these 9 degrees of freedom for the bound state in terms of the center of mass motion, rotational and vibrational modes of the bound state. Clearly, there are 3 degrees of freedom for the translational center of mass motion, and you have either 2 or 3 rotational degrees of freedom depending on whether or not you have a linear moelcule or not. In case of a non-linear molecule, you can chose 3 independent axes of roitation, so you have 3 degrees of freedom for rotation. In case of a linear molecule the axis parallel to the molecule is not allowed. The reason for that is that this correponds to a spin degree of freedom of the atoms, which we didn't consider in the total of 9 degrees of freedom. So, we have:

total number of degrees of freedom = 9 = N vibrational modes + 3 translational center degrees of freedom for center of mass + 2 or 3 rotational modes.

So, you can solve for the N vibrational degrees of freedom for the cases of linear and non-linear molecules. Then, the heat capacity per molecule is obtained from the equipartition formula. Since each vibrational modes contributes to two quadratic terms in the Hamiltonian, you get:

C_v = N k_B + 3/2 k_B + (2 or 3)/2 k_B

Count Iblis (talk) 01:31, 7 February 2011 (UTC)[reply]

Will it be the same for both ideal and real gases? — Preceding unsigned comment added by Krishnashyam1994 (talkcontribs) 09:07, 7 February 2011 (UTC)[reply]

For real gases the total heat capacity will be different due to the potential energy between the molecules. However, the contribution due to the translational, rotational and vibrational degrees of freedom will be the same. Of course, you can still question the exactness of these contributions to the heat capacity. The contribution 3/2 k_B to the translational modes to the heat capacity is almost exact, the corrrections coming from quantum corrections that are only important at extremely low temperatures (usually less than 10^(-10) K). For the vibrational modes, the opposite is true. In most cases, quantum effects leads to these being frozen well above room temperature. Then a few hundred K above room temperature where you would expect the formula to hold, you will see deviations, because describing the molecule as being bound by a harmonic potential isn't that accurate. Then the rotational modes are typically frozen below 100 K or so. There are obvioulsly corrections to the classical formula due to quantum effects. Also, there is a coupling between the rotational modes and the vibrational modes. E.g. if the molecule rotates faster, it stretches a bit which causes the moment of inertia to be larger. So, there is an inherent contradiction in treating the molecule as a rigid rotator and a harmonic oscillator at the same time. Count Iblis (talk) 14:16, 7 February 2011 (UTC)[reply]

Tank filling on a cold day

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Is it better to your pocket? Gasoline will have less volume, but does it matter? — Preceding unsigned comment added by Quest09 (talkcontribs) 12:10, 6 February 2011 (UTC)[reply]

I seem to recall a discussion on this before but can't remember where. In any case, [1] suggest the change in density is only about 0.5% change for 5 degree C change in temperature. In other words even if there's a 30 degree C change between day and night thats only 3% difference. More to the point [2] which is the ref used in the earlier source and [3] mention 2 key things. Number 1 many petrol stations have their tanks underground where the temperature change over the course of a day is minimal. Even if they don't, a large volume of petrol probably doesn't change temperature over the course of the day that much anyway. So this may be an issue in summer vs winter, but day vs night not so much. And even then as both refs mention, most modern pumps are probably sophisticated enough that they do take temperature in to account (and in any case would I expect be periodicly recalibrated probably more then once a year). Nil Einne (talk) 12:36, 6 February 2011 (UTC)[reply]
Not to mention that prices fluctuate much more over the year than the density possibly could anyway. –Henning Makholm (talk) 13:18, 6 February 2011 (UTC)[reply]
This explains it nicely: Consumer Watchdog--Aspro (talk) 19:05, 6 February 2011 (UTC)[reply]
This Fuel dispenser#The metrology of gasoline talks about it a bit. Basically in Canada where the cold temperatures hurt the gas sellers they compensate for the difference. Same for the wholesale level. But in the warm US they don't (the warm south more than compensates for the cold north). People think that's unfair but it's not unfair enough for anyone to get worked up enough to do something about it. Ariel. (talk) 19:10, 6 February 2011 (UTC)[reply]
The petrol is stored underground, which means there will be very little temperature variation during the day due to the insulating properties of the ground. There will be a variation from season to season, possibly, but you can't really wait until winter to fill up! --Tango (talk) 22:35, 6 February 2011 (UTC)[reply]
From the consumer watchdog PDF linked above 513.8 million gallons of gasoline sold in the summer 2007 will be attributable to the thermal expansion of gasoline. can I just say I had to nudge my eyes back into their sockets. It still doesn't fail to stagger me every time I hear statistics about how much gas we churn through, I think this should really be something kids are taught in schools. We've reached peak oil already, if you argue we haven't, then you can't argue will very very soon, and most people are still completely oblivious to the staggering amount of resource we pull out of the ground and burn every year.. Vespine (talk) 01:27, 7 February 2011 (UTC)[reply]
Volume statistics get impressive very quickly; still, consider that this is only 800 times larger than one gallon of gas on a side. At a cost (rather optimistically) of $3 a gallon, that is $1.5 billion worth - the price of four or five Boeing 747s. Wnt (talk) 18:28, 10 February 2011 (UTC)[reply]

Magma

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A while ago I recall a wiki user stating that the Earth's structure is solid throughout. Meaning that if you drill down to the core, you won't encounter magma (he said magma was formed through other means). I'm sure the outer core is liquid, but is it magma? The article on mantle states part of it is melting. Would that be magma? If we were to drill down to the core of the planet, would we eventually encounter magma? ScienceApe (talk) 15:02, 6 February 2011 (UTC)[reply]

Magma is formed when part of the earth (mantle or crust) melts because conditions locally (e.g. relatively high levels of water i.e. above a subduction zone or areas where the temperature is relatively high considering the pressure i.e. decompression melting) mean that the melting temperature is reached. Only part of the rock actually melts (partial melting) and a magma forms when the melt rises and starts to form distinct bodies of molten rock. This is different from the outer core, which is all liquid. You would only encounter magma on drilling if you did it at one of the locations where partial melting is happening. Mikenorton (talk) 15:26, 6 February 2011 (UTC)[reply]
Do you mean the "outer core is all liquid"? All of the links in this vicinity describe the inner core as solid. SemanticMantis (talk) 15:37, 6 February 2011 (UTC)[reply]
I am getting mixed up in my old age - corrected. Mikenorton (talk) 16:03, 6 February 2011 (UTC)[reply]
Our article on Structure of the Earth tells us "The liquid outer core surrounds the inner core and is believed to be composed of iron mixed with nickel and trace amounts of lighter elements." So no, the outer core is not magma. SemanticMantis (talk) 15:30, 6 February 2011 (UTC)[reply]
(ECx2) Well Structure of the Earth says "The liquid outer core surrounds the inner core and is believed to be composed of iron mixed with nickel and trace amounts of lighter elements." This doesn't sound much like what people commonly think of as magma which is of course discussed in our article. I'm suspect the temperature and pressure differences with places were magma is formed are enough that even if it were rock you wouldn't get something people would think of as magma either. Nil Einne (talk) 15:34, 6 February 2011 (UTC)[reply]
So would it look like liquid metal? ScienceApe (talk) 17:28, 6 February 2011 (UTC)[reply]
The asthenosphere of the mantle is generally semi-solid, but the lower mesosphere is solid. ~AH1(TCU) 18:24, 6 February 2011 (UTC)[reply]
The asthenosphere is fully solid (apart from a suggested 1% melt), but at the slow rates of deformation that occur in the uppermost mantle it acts like a highly viscous fluid, a form of rheid. As to the appearance of the outer core, we have no way of knowing - the conditions can be recreated using a diamond anvil cell in the laboratory but we can't look at it as the sample is so small. Mikenorton (talk) 19:23, 6 February 2011 (UTC)[reply]
The liquid outer core is composed primarily of metals. But it may or may not look like molten metal at atmospheric pressure. SemanticMantis (talk) 19:58, 6 February 2011 (UTC)[reply]
The inner core would look like molten metal at atmospheric pressure (assumin the temp stayed the same). The only reason the inner core is solid is the massive pressure that it is under. For example, Ice VII is a form of water ice that doesn't melt until over 400 degC because it is at 10 GPa. Googlemeister (talk) 15:05, 7 February 2011 (UTC)[reply]

Refilling the Ogallala aquifer

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One of the leading regional creeping-doom scenarios in the U.S. concerns the rapid draining of the Ogallala aquifer, leading to reduced potential for agriculture throughout much of the Great Plains. What I don't understand is that the barrier to refilling is apparently mostly a matter of permeability, and there are four major rivers crossing the aquifer region. Why don't people just drive wells down from the river to the aquifer every hundred yards for its length to refill it? (To avoid confusion, I mean wells with some degree of filtering, close to the surface of the water) Wnt (talk) 21:29, 6 February 2011 (UTC)[reply]

Well, there are also major disputes about the usage of water from the rivers. For example, Nebraska and Kansas have been involved in lawsuits about Republican River water rights, and Nebraska and Colorado have struggled with rights to the South Platte River. In recent years it has been common for the middle Platte River (upstream of Columbus, Nebraska, where it is joined by the Loup River) to dry up completely in the summer. I'm sure similar issues occur in states other than Nebraska; I only know of these examples because Nebraska is my home state. For more information, you might try http://water.unl.edu/. —Bkell (talk) 21:40, 6 February 2011 (UTC)[reply]
Obviously rivers are not infinite supplies of water. If you were to drain hydrologically significant quantities of water from the river, in order to "re-fill" the aquifer, you'd be extracting enormous quantities of water; and you can't just assume that "more river water will just keep flowing." Extraction of such volumes of water would have as much ecological impact as the depletion of the reservoir in the first place! The water cycle is a closed system - if the aquifer is being depleted, the water is ending up somewhere else. The real issue is, though, that where it ends up is not economically useful. The water that has been extracted from the aquifer be distributed globally in the form of increased precipitation somewhere else in the world. If the water is pumped out for crops and agriculture, and significant amounts undergo evapotranspiration and end up as rain over the Atlantic Ocean, then that freshwater is "lost" as a useful reservoir. However, that means that there's more water in the ocean, and less in the atmosphere; so there will be increased oceanic evaporation, and new clouds will form, and rain will precipitate somewhere else (maybe in Africa or Asia or the Pacific). If we're lucky, and if all things were "equitable and fair," this would also mean more rain in the Mississippi River basin - so the rivers would have higher throughput, so we could sustainably "drain off" a few billion gallons per year to "pump back into the ground." The point is, though, that the implications of hydrology on the scales of continent-sized aquifers are part of the entire global climate system. For every place that undergoes desertification or aquifer depletion, somewhere else on the planet is receiving more fresh-water. Unfortunately, this redistribution often occurs in a way that is neither useful for human economic activity or agriculture, nor for ecosystems. If you could make a convincing scientific case that depleting the river water flow, and pumping or "sequestering" water in an aquifer would actually result in increased economic activity, you'd have an easy time finding major industrial sponsors to start the pumping. Nimur (talk) 22:17, 6 February 2011 (UTC)[reply]
I really doubt that "For every place that undergoes desertification or aquifer depletion, somewhere else on the planet is receiving more fresh-water." There's no reason why the oceans couldn't give up a few inches of water and all the land would become wetter, if local conditions permitted it. That said, if the river is being sucked dry, obviously that's a problem. I still think of the area as a place for "500-year floods"[4] but of course that's not every year. I'd call it a missed opportunity, but then again, I don't know how well the system would work in muddied raging floodwaters anyway. Wnt (talk) 01:41, 7 February 2011 (UTC)[reply]
You're right; I should clarify that if the "conserved quantity" of fresh water ends up raining in the ocean, it's no longer really "fresh water." If climate-sized quantities of rainfall over the ocean change, the salinity will decrease by some microscopic amount, but that's not really helpful (it's still not going to be "freshwater"). My earlier comments were not meant to imply that there's a fixed amount of fresh water that we're guaranteed to always have distributed throughout Earth. Nimur (talk) 02:50, 7 February 2011 (UTC)[reply]
You would also have to worry about contamination of the aquifer. I do not have pollution data handy, but I would expect that a deep aquifer would have less pollutants then a surface river which gets fertilizer runoff. Googlemeister (talk) 14:59, 7 February 2011 (UTC)[reply]
My feeling is that runoff that makes its way down through natural rock from the fields themselves would be worse, but I don't really know. It is an interesting idea for a whole new kind of ecological disaster: bacterial overgrowth and contamination in aquifers due to excessive nutrients. New idea, new environmental disaster - that's about the pace of things, isn't it. But I wonder if those farmers' fields could invent the problem on their own. Wnt (talk) 18:12, 11 February 2011 (UTC)[reply]
What's really needed is a way to get flood water down into the aquifer, properly filtered, rather than have it flood people's homes. However, the engineering challenge of processing such huge volumes of water would make this impractical. StuRat (talk) 06:41, 10 February 2011 (UTC)[reply]
Since the Laurentide ice sheet was likely a major source of the aquifer, the lack of any similar source today limits the degree to which the aquifer can refill. ~AH1(TCU) 22:58, 11 February 2011 (UTC)[reply]

How deep is the deepest parking garage? Could one ever be built deep enough to reach Hell, like in this commercial?

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This 2003 Honda Pilot Commercial depicts a full parking garage for the first many levels. Soon, they reach some humid utility area 96 levels down, and eventually a Hell-like cavern 720 levels below.

The head sticking out appears to be the last sentry of Upper Hell before the realm's exit, and what a surprise - there are still lower levels.

For those of you who don't believe in Hell, could one ever be made deep enough to reach a Hell-like place?

Anyway, what has been the deepest parking garage ever made and what feats of engineering and financing would it take to reach a Hell-like area below the surface? At what depth/floor level would it get unrealistic and why? --70.179.181.251 (talk) 22:00, 6 February 2011 (UTC)[reply]

You mean down into the mantle? I suppose it would be possible, but possible and practical are two very different things. The mantle is 75 km below the surface in places. Building a car garage even close to that depth would need an elevator, and fan system to remove carbon dioxide, and a humidity regulator. Sure, it can be done, but that's an idea like a floating city - possible, but completely pointless. One thing that should be noted is that it's not like a surface that you break through and then magma; the rock gets more and more plasticy as one goes down. You also only need to go down a few miles before it starts to get noticeably hotter. --T H F S W (Contact) 22:08, 6 February 2011 (UTC)[reply]
Just in terms of feasibility, it's of note that the lowest point ever drilled by humans — the Kola Superdeep Borehole — was only about 12.3 km below the surface, and that was not very easy. --Mr.98 (talk) 01:40, 7 February 2011 (UTC)[reply]
That also links to Extreme points of Earth#Lowest point (artificial) which notes the 'lowest human-sized point underground' is the TauTona Mine which is 3.9 kilometers deep. Our article notes 'The journey to the rock face can take 1 hour from surface level. The lift cage that transports the workers from the surface to the bottom travels at 16 metres per second (58 km/h).' I don't know if there's any shaft large enough for a car, perhaps not. As for 'hell like' well 'The mine is a dangerous place to work and an average of five miners die in accidents each year' ('employs some 5,600 miners') and 'Air conditioning equipment is used to cool the mine from 55 °C (131 °F) down to a more tolerable 28 °C (82 °F). The rock face temperature currently reaches 60 °C (140 °F)' Nil Einne (talk) 06:10, 7 February 2011 (UTC)[reply]
I see a couple of places that were planning to have seven underground parking levels, one in Vancouver and another in Chicago. Don't know if either got built. Clarityfiend (talk) 22:29, 6 February 2011 (UTC)[reply]
The Torre del Caballito in Mexico City reportedly has 15 (fifteen!) underground parking levels. I don't know if that's a world record, but I couldn't readily locate anything deeper. TenOfAllTrades(talk) 03:04, 7 February 2011 (UTC)[reply]
I love the "For those of you who don't believe in Hell"! Even if I believed in Hell, could I seriously believe that it is inside the Earth? If so, I would start a campain for the governements get drilling and free those souls! --Lgriot (talk) 10:55, 7 February 2011 (UTC)[reply]
Do you also want to campaign to go around all the maximum security prisons opening doors? If you believe in Hell, you probably would believe that they are there for a reason. Googlemeister (talk) 14:53, 7 February 2011 (UTC)[reply]
I am sorry my irony in this post didn't get through. The underlying assumption is that God, being all-knowing, including our future, knew that these people would have a bad life, yet, he let them be born, and after their death let them then be condemned to hell. So my view is that God is a very bad being to let people be born, have a bad life and then punish them for something he knew would happen and let it happen anyway. To punish him, we should free all the bad and let them loose in heaven where they can think of ways to annoy God. that would be fun to watch, wouldn't it? It isn't the same as human justice where the judges are genuinely not responsible for the prisonners actions (well, most of the time). --Lgriot (talk) 15:43, 7 February 2011 (UTC)[reply]
But logically, God would know what you were going to do, and having infinite power, could stop you if he felt it would actually be irritating, so it really wouldn't work. Googlemeister (talk) 16:07, 7 February 2011 (UTC)[reply]
Again, failed, sorry. I seem to have a problem making Googlemeister understand that I am joking. Maybe because I am the only one to see how funnily ridiculous the idea of an all powerful god is? --Lgriot (talk) 08:59, 8 February 2011 (UTC)[reply]
I think we could make a fair scientific argument for opening the prisons - or rather, can anyone show evidence that having them is useful? At least in the U.S., which invented them and seems to think that they can cure virtually any problem whatsoever (and when they don't, that's irrelevant). As for Hell, well, if God is an author, and he throws rough drafts that aren't going anywhere into the fire, then the fire burns always, the drafts burn but a moment, and the characters in those drafts do not suffer, but neither are they saved. Wnt (talk) 17:22, 7 February 2011 (UTC)[reply]
The US invented prisons ? No, they've been around as long as civilization, probably longer. While they seem to be fairly useless at reform, they do prevent many crimes, since criminals spend years removed from potential victims. StuRat (talk) 18:56, 7 February 2011 (UTC)[reply]
While I agree the idea the US invented prisons is bizzare, you appear to have a fairly naïve view of the interaction between crimes, prisons and criminals. In particular, you appear to be assuming prisons make no difference as to how likely a criminal is to commit a crime. Yet there is some evidence prisons may in some instances increase the likelihood someone will commit further crimes in the future, for example by these related issues of teaching someone to be a better criminal, by disconnecting someone from society, by for lack of better description 'reducing their humanity', making it more difficult for someone to interact acceptably in society (e.g get a legitimate job), and simply by familiarising someone with criminals and crime as a way of life. If you lock someone up for 20 years of their life in total and they commit 10 crimes during that life regardless vs if you don't lock someone up at all and they only commit 5 crimes during their live then clearly you have not prevented many crimes but increase the number. And many would agree some crimes are worse then others so going solely by the number doesn't work very well anyway. And without getting in to rehabilitation at all, all that money you spend on prisons as well as associated costs like courts and police is money you can't spend elsewhere, whether you believe that should be improving the lot of those in a very bad situation or reducing taxes. (If you believe prisons do reduce the number of crimes then the cost of running prisons can partially be offset against what you save from the reduction in crimes but as I've said that hasn't been established.) Note that I'm not arguing completely removing punishment or justice would result in less crime personally I don't believe it will although I do agree with Wnt that the current system in the US isn't working very well but that's somewhat beside my point which is you can't simply say 'people in prison can't commit crimes so you have less crimes/victims' since there is clearly a complex interaction, the fact people in prisons can't commit crimes doesn't help you if people are more likely to commite crimes when they aren't. Nil Einne (talk) 05:42, 8 February 2011 (UTC)[reply]
I think by the time most people end up with prison sentences, they are already career criminals. First time offenders typically don't get caught, or, if caught, aren't charged or get a suspended sentence or community service. However, another factor supporting your contention, is that some crimes seem as though they are likely to occur regardless of the criminal. If you arrest a drug dealer, another will work the same location to supply the customers there. If you arrest a hit man, those who would have hired him just hire somebody else. StuRat (talk) 06:02, 8 February 2011 (UTC)[reply]
I'm pretty sure that depends where you live. In any case, even in the US there have been notable cases with the Three strikes laws where someone has been sentence to very long prison terms for what seem like minor offences long after their previous convictions (which were usually more serious convictions). I'm not sure if you consider these people 'career criminals' and these may have been an exception and while given how long these sentences are I'm guessing most of these are still in prison it's unclear to me that they would have necessarily commited any further crimes had they not been locked up and in particular it seems hardly surprising if these people will have a major slide back downwards so that when they are released they will be more likely to commit crimes...
I'd call the grammar police on you for that 84 word run-on sentence, but you'd probably just get off with a warning, if this is your first offense. :-) StuRat (talk) 06:29, 10 February 2011 (UTC) [reply]
You might want to take a look at When the World Screamed first. --Stephan Schulz (talk) 11:08, 7 February 2011 (UTC)[reply]
I have to admit, I didn't think anyone still believed that hell was literally, physically inside the Earth. APL (talk) 17:31, 7 February 2011 (UTC)[reply]
I don't believe in any sort of literal hell. But hell is certainly a fun theological and philosophical tool for analyzing meaning and reality and destiny. Modern views vary widely, ranging from purely secular interpretations of the writings in the various holy-books, to mainstream theological interpretations in major world religions. Here's our article on Hell in Christian theology - I bring this up because Pope John Paul II reversed some major Catholic doctrine in the 1970s by stating that hell wasn't actually inside the Earth; in this 1999 speech, he said it's not a place at all. That should give you some perspective on just how modern that viewpoint is. More recently, in 2007, Pope Benedict has emphatically denied John Paul II's statements, claiming that Hell is actually a real place inside the Earth. Unfortunately, Popes tend to speak a cryptic and poetic dialect of heavily-Latin-influenced Italian, and rarely go to great lengths to unambiguously clarify their dictums; much meaning is lost through translation and interpretation. (It is my opinion that if any religious doctrine were to be laid out in unambiguous and clear language, the silly ideas could be easily refuted, leaving only a modernized, secular philosophy). I'm neither a Catholic nor very religious at all, but I have read many of John Paul II's speeches and writings, and I can say that he was a much more rational and intelligent pope than most - a suitable religious leader in the era of space travel and scientific reason. Nimur (talk) 21:01, 7 February 2011 (UTC) [reply]
Neither of those external links actually say what you say they say. Is that intentional? Some sort of test to check people are actually following links? John Paul II was referring to what was already in the Catechism (he refers to it by name) in saying that Hell is a state of being: he makes no mention of it being 'inside the Earth' because that hasn't been Catholic teaching since I don't know when. Benedict XVI says that Hell is very real, even though people don't talk about it much anymore, and it is a state of separation from God: he makes no mention of location or of it being 'inside the Earth' because that hasn't been Catholic teaching since I don't know when. He is particularly talking to support the new version of the Catechism, which explains (again) that Hell is a state of separation from God with no particular worldly location. Seriously, your links say nothing even close to what you say they do. Benedict XVI is a smart cookie steeped in rational study (of Catholic and related theology), although he sometimes forgets his audience and ends up too esoteric. 86.162.68.36 (talk) 22:36, 8 February 2011 (UTC)[reply]
In fact, this must be a test to see if people are actually following your links, because the very internal link you provided explains that neither Pope was saying what you said they were saying, and that this is a piece of misinformation spread by misreporting. Either that, or you don't read the links you provide yourself... 86.162.68.36 (talk) 22:46, 8 February 2011 (UTC)[reply]
I respectfully disagree with your assertions, but I'll concede that I may have read my own interpretation into the speeches in the links I provided. If anything, that only solidifies my earlier assertion that the Pope(s) used ambiguous language. Nimur (talk) 07:44, 9 February 2011 (UTC)[reply]
I came here to apologise for harshness of my phrasing, because there was no need to be unpleasant. Sorry. But I am genuinely baffled by how you can have thought that was what they were saying. I mean, it's right there in your links that both agree with each other and are saying things that were already Catholic teaching. All I can think is that you saw the word place and automatically thought that meant "place within the Earth", but that makes no more sense than assuming that any reference to Heaven as a place means "a place in the sky we could find with a rocketship". This very misunderstanding of the word place is why many (particularly in the 20th century) have preferred to use the word state, although in either case they are referring to a situation that souls experience, which is not in this world. Taking it as someone is very versed in Catholic theology, there was no ambiguity at all for me in their words, except in the usual "this is the limit of what we feel we know, so I'm phrasing it to make it clear I'm not insisting on something being true which is a matter of individual faith" sort of thing. The alternative is that a Pope or priest lays out some alternatives and explains who has argued them and how, but that tends to get misreported too, and can get long and uninteresting for much of the laity. 86.162.68.36 (talk) 09:25, 9 February 2011 (UTC) [reply]

This does bring a scientific question to mind after all: is there anywhere that you can actually encounter lava magma (??) in an underground cave? I know of course about lava tubes, but they seem too close to the surface and too transient to count. I mean, is there anywhere in the world that you find lava/magma bubbling away in a rock formation that hasn't been fresh-frozen from it, which is deep under the ground? Or is every volcano found on the surface, simply because the time for the magma to rise all the way up is so short in a geologic sense, and the area where caves are found is so small? Wnt (talk) 09:47, 10 February 2011 (UTC)[reply]