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May 20

What labs, books, and conferences are there about research on the neuroscience of empathy?

I want to make this list more complete.

Specifically, what are the: a) labs or primary researchers b) books c) conferences d) one-off papers

... which have to do with the neuroscience of empathy?

Please include only primary academic sources - i.e. not popular press, unscientific publications, or the like. (Exception: popular-format books by people who are in fact real researchers are OK, e.g. most of Paul Ekman's recent books.)

Most important to me is the list of labs / researchers, preferably with links to pages where I can directly download PDFs of their papers, as the primary use for this list is as a list of places I should apply to for my PhD.

Thanks!

Sai Emrys ¿? ✍ 00:26, 20 May 2009 (UTC)

You could start here. --Tango (talk) 00:29, 20 May 2009 (UTC)

The Society for Neuroscience annual conference is in Chicago, October 17-21. You may consider attending and finding out for yourself what you like and where you should apply. I don't know if you have to be a member to attend (I'm a member anyway), but it's easy to find out. The SFN homepage is at http://www.sfn.org/ . Also, Tango's advice is really good. Just google or google-scholar for "empathy", "neuroscience", "mirror neurons", "insula", "anterior cingulate", or any combinations thereof, and you will find all you are looking for and more. And, good luck! Empathy is really a fascinating research topic. --Dr Dima (talk) 01:35, 20 May 2009 (UTC)

Hmm, I wouldn't really recommend going to SFN in order to find a school, it's kind of an overwhelming experience. Anyway, if I had to recommend a place to somebody who could get in anywhere, I would recommend University College London, with the Friths, Ray Dolan, etc. It's a hot topic, though, and there are people all over the place working on it. Looie496 (talk) 02:38, 20 May 2009 (UTC)

I'm afraid the $550 (+ hotel & travel) non-member price is a bit too steep for me; otherwise, it looks interesting... but very general. I'm only interested in (dedicating my life to) limited parts of the field of neuroscience; I feel a general conference would be a bit too shotgun. (FWIW, I'm very disappointed I missed the Berkeley conference on mirror neurons recently - I heard of it too late. I live in Berkeley, it was exactly on MNs, and it was free to boot! Sigh.)

Yes, I know how to use Google Scholar; my hope was to find somewhat more personal pointers, as GS can be a bit like finding a specific kind of needle in a stack of popularity-ranked hay. I'd love to, but practically speaking there's no way I can actually read through all the stuff there to find out the handful of people whose research is really what I want. This is something that domain knowledge is very helpful for making a lot easier. Thanks! Sai Emrys ¿? ✍ 02:48, 20 May 2009 (UTC)

Many conferences use student volunteers to man the doors, check badges and such like. When you do that, you can generally hang out at the back of the conference hall while sessions are in progress and catch most of the event for free. Obviously travel and accommodation is still an issue. But it's worth calling the conference organizers - expressing your enthusiasm and interest for this narrow field - they may be able to cut you a deal - or even offer a small grant/scholarship to help to get you there. It's definitely worth a try - especially with such a tightly focussed conference. SteveBaker (talk) 03:59, 20 May 2009 (UTC)

Ah, you're in Berkeley -- and I see from your resume that you got an undergrad degree there. The best advice I can give is to try to get a "technician" job in a lab that does something similar to what you're interested in -- there are several people there interested in social neuroscience, and all of them are top notch. There's nothing better than hands-on experience for getting a good fix on who is doing the stuff you care about most, and it's also a big plus for getting into a top-notch program. (To Steve: SFN is one of the largest academic conferences in the country, with typically about 50,000 attendees -- tightly focused is not what I would call it. It's a circus. They do provide a bit of support, but they wouldn't support somebody who isn't currently in an academic program.) Looie496 (talk) 04:26, 20 May 2009 (UTC)

Throwing a ball of wool (or twine) to a lion/tiger...

What happens? Do big cats also find it entertaining to play with suchlike? --Kurt Shaped Box (talk) 02:22, 20 May 2009 (UTC)

The Desert Museum puts ice in the mountain lion cages for their enjoyment if I remember correctly. A google of zoo lion enrichment found this website which says: "To stimulate predatory behavior, keepers toss hay-filled burlap sacks or cardboard boxes into the lion and tiger enclosures, which the cats pounce on and shred as if they were prey. Keepers may add olfactory interest to these items by scenting them with zebra or camel urine, perfumes, hunting lures, and herbs. In the tiger yard, keepers can hook up to a tree a giant spring covered with PVC pipe to which they attach a hard plastic Boomer Ball® or burlap sack. The tigers attack and tug at the unyielding item as if it were struggling prey. For the small cats, keepers hide meat and prey items throughout the enclosures. In the summertime, the fishing cats hunt for live goldfish released into their pools." A search for zoo enrichment might yield some more results. My guess is that a suitably sized ball of twine would generate interest from a large felid, but a zoo might not put an object which might present a tangling or choking hazard in their enclosures. If they could keep them from unravelling it enough to choke or tangle it might work. A zoo keeper would be a good person to ask. Sifaka ^talk 03:10, 20 May 2009 (UTC)

Certainly I've seen balls in big cat zoo exhibits - so I presume they play with them. I doubt it matters much whether it happens to be a ball of wool or a plastic soccer ball or whatever. Of course this is all about zoo animals - who need all of this 'enrichment' to keep them interested in life in their tiny enclosures with all of their natural instincts being effectively turned off. Whether a wild Lion or Tiger out there in it's native habitat would give a ball of wool a second glance is an entirely different matter...I suspect the very young ones would - but not the adults. SteveBaker (talk) 03:52, 20 May 2009 (UTC)

Genus

Where can I find information describing when a genus split from others in its family? Specifically I am writing about genus Abramites, though specific information isn't neccesarily needed, just how to find it.Drew Smith What I've done 07:13, 20 May 2009 (UTC)

First a remark: I'm no expert in fishs or phylogenetics, just a geneticist. I think, there is no clear answer to your question. Even for families that are "hot research topics" like hominidae the exact time points of speciation are unknown. All you can do is apply a model of the time course of genetic changes, and then come up with some rough estimate how much time it took to accumulate the differences you see. A quick googling didn't bring up any research paper that did this for Abramites, though, so I think the answer is: No one really looked into this. TheMaster17 (talk) 09:14, 20 May 2009 (UTC)

Meh. I came to the same conclusion, just wondered if anyone knew of a site or book that specialised in this kind of thing.Drew Smith What I've done 11:17, 20 May 2009 (UTC)

So, for the taxobox, is it ok to use the time period that the order first appeared?Drew Smith What I've done 11:19, 20 May 2009 (UTC)

Butterflies/moths identification

• 
  Diacrisia sannio
• 
  Pyrgus (species uncertain)
• 
  Hamearis lucina?

I took some pics of butterflies a couple of days ago and I wasn't able to fully identify them. I have some hints about the genus/species for two of them, but I can't be sure. The pics were taken in southern Romania, in a forest along the Dâmboviţa river. Can anyone help? bogdan (talk) 09:45, 20 May 2009 (UTC)

The first is a Diacrisia sannio, the second probably a Pyrgus armoricanus or a Pyrgus malvae and I can't be sure about the last. BTW I used this amazing website to do the identifications [1]. Mikenorton (talk) 15:45, 20 May 2009 (UTC)

Thank you, both for the identification and for the link. bogdan (talk) 20:43, 20 May 2009 (UTC)

Work = Force*Distance or = Force*Time?

I have a textbook saying the work done is the product of the force applied and the distance the object moved. But is this ultimately right? Because if I apply the same force for the same time to a faster-moving object, it would result in more work done. Or the distance moved by initial speed of the object must be subtracted from the distance? Work = Force*Time seems better to me. Like sushi (talk) 11:44, 20 May 2009 (UTC)

No, it's right. Force*Time is momentum. Kinetic energy ("work" just means "energy added") is proportional to the square of velocity, rather than velocity itself, that is the key point. The energy required to make a 1kg object go 1m/s faster depends on the initial speed - if it starts off stationary you need 1/2mv²=1/2J, if it starts off at 10m/s you need 1/2m(11²-10²)=10.5J. --Tango (talk) 12:13, 20 May 2009 (UTC)

Thank you. Then the same force applied for the same time could mean different work done?Like sushi (talk) 12:25, 20 May 2009 (UTC)

Yes. Consider a constant 10N force applied to a 1kg mass starting from rest. In the first second the mass accelerates from rest to 10 ms^-1, so the work done is 50 J. In the next second the mass accelerates from 10 ms^-1 to 20 ms^-1, so the work done is 150 J. Gandalf61 (talk) 12:36, 20 May 2009 (UTC)

Does that mean the object moving, no force applied, also, well, having work?

Like sushi (talk) 13:09, 20 May 2009 (UTC)

An object moving with constant velocity has constant kinetic energy. Work is the increase in energy, which would be zero. --Tango (talk) 13:19, 20 May 2009 (UTC)

Even though I have no doubt about the formulas, it has always bugged me that KE is quadratic in velocity, and that (as a result) it's not force times duration. What your intuition is picking up on is momentum, not work; the (change in) momentum is the product of force and time, and is called impulse. --Tardis (talk) 13:09, 20 May 2009 (UTC)

We must note that the formula Work = Force x Distance is not exactly right. There are two..erm.. errors. (i) It should be displacement, not distance. Note the difference. Distance is the total length of the path traversed. Displacement is just the distance between the initial and final points alone. For example, if you move on a semicircle, the distance is the length of the path, namely pi*radius. But the displacement is merely the distance between the initial and final points, which is twice the radius. (ii) This formula is valid only for a constant force. For a time varying force, this must be integrated along the path to get the work done, so keep it in mind to apply this formula only for constant forces. Rkr1991 (talk) 12:46, 20 May 2009 (UTC)

There's one more problem. It should be the dot product, not the cross product. The cross product will get you torque. — DanielLC 15:15, 20 May 2009 (UTC)

Did anyone say cross product? I think we were all talking about the 1D case. --Tango (talk) 15:18, 20 May 2009 (UTC)

Still, it doesn't cost any extra to adapt it for the more general case. I was having the same thought as DanielC. —Tamfang (talk) 02:24, 21 May 2009 (UTC)

It costs understanding for people that aren't familiar with vectors. You don't know if the OP knows anything about vectors or not. --Tango (talk) 14:54, 21 May 2009 (UTC)

Since Rkr1991 made a point of distinguishing between displacement and distance, I wouldn't bet against Rkr's understanding the basics of vectors. —Tamfang (talk) 03:22, 25 May 2009 (UTC)

Rkr1991 is not the OP (despite the indentation). --Tardis (talk) 14:50, 27 May 2009 (UTC)

So? Rkr was the only one in this thread to use 'x' for multiplication, and DanielC (and I) criticized Rkr for it, not the OP. Are you suggesting that writing '·' rather than '×' would confuse the OP? —Tamfang (talk) 19:08, 4 June 2009 (UTC)

How to best boil water?

If we try to heat something by burning fuel, common sense tells us that there is a certain most suitable magnitude of fire. Setting aside the effect of incomplete combustion, (if we use a mixed gas of combustable and oxygen,that will be avoided) Is it better for energy efficiency to make the fire as large as possible, or as small as possible, or there is a golden middle? If we heat it too slowly, the heated object seems to cool down while heating, on the other hand, if we are not trying to heat all the surroundings, the heated gas seems to drive away the gas still not having cooled down yet, and thus, a loss of energy. Like sushi (talk) 12:16, 20 May 2009 (UTC)

It's not really the size of the fire, but the efficiency of getting the heat from the fire to the water. Storm kettles are very good in that regard. The most efficient way to boil water is, I believe, with an electric kettle, though. --Tango (talk) 12:40, 20 May 2009 (UTC)

My mother's coffee-making device heats the water as it's coming out. This has the distinct advantage of not having to heat more of the water than you're going to use. This is somewhat off-topic, though, since you're asking about fire.... 90.193.232.41 (talk) 18:02, 20 May 2009 (UTC)

To efficiently use a kettle or pan of water on the gas range (or "hob"), adjust the flame so that the bottom of the vessel is heated without excess heat escaping around it. This will not make it boil faster, but will get the job done with less fuel. A larger vessel may need a larger flame. A covered pan will boil faster than an open one. The use of water from the "hot" tap is to be avoided for cooking, since it may have more dissolved undesirable substances. With an electric Calrad type burner, select a setting which again matches the size of the heated area to the size of the bottom of the pan. The same quantity of water should boil quicker in a broad pan than a narrow one due to the larger heated surface. A pan with copper cladding might heat quicker than an all steel or thick cast iron one. I suspect that a black or dark bottom pan would absorb heat faster than a white or reflective metallic one, unless the dark coating is thick enough to act as insulation. Edison (talk) 23:06, 20 May 2009 (UTC)

You would be better off just moving to a country with a mains voltage that allows decent electric kettles. In the UK you can easily get 3kW kettles that boil water far more quickly that you would on a hob. --Tango (talk) 16:25, 21 May 2009 (UTC)

Yes, those can be extremely efficient. I'm not entirely sure how they work, do they need time to charge inbetween uses? --Tango (talk) 16:25, 21 May 2009 (UTC)

Unability to lose fat?

I have been working out for the past six months and I have lost a lot of body fat and gained muscle which I am very happy. I am female and have naturally very thin arms and legs so, as you can guess, I tend to gain weight in my torso. However, all these months, my stomach and back fat have remained the same. It doesn't matter how many miles I jog, sit ups and push ups I do, kickboxing (one hour session - 5 days a week) AND playing basketball and volleyball per week. FYI - doc said at my checkup that I am healthy and eat right but I need to lose weight in my middle. He said something about women who are apple shaped are likely to have heart attacks when older. I know that I am genetically predispositioned (mom is short and pudgy) to have a pot belly but it possible for some people to never lose that fat? --Reticuli88 (talk) 12:50, 20 May 2009 (UTC)

Your question appears to be asking if there is a medical justification for your inability to lose fat. That requires a medical diagnosis. It is impossible to give a medical diagnosis over the Internet. If you simply want information on medical studies about fat loss, please ask specifically for information about medical studies. Do not include personal medical information. As it is, your question is too much a request for medical advice to be answered. See the guidelines at the top of the page - we will not provide medical advice. -- kainaw™ 12:56, 20 May 2009 (UTC)

(Non medical oppinion). A lot of the health freaks at my gym talk about hitting "plateau", for either weight loss or gain. Seems the human body gets used to certain level of regular exertion and calorie intake. They generally suggest changing your regime to suprise the body again - so either a further reduction in calorie intake (booo!), or mixing up your excercise for a while, such as swimming / lifting weights, while giving the running a rest.

Does anyone know how much the body adapts to a diet (or can point to a journal)? I know i can reduce by 500 Cal/day from the average 2500 and it makes no difference, but reducing by 1000 Cal/day causes weight loss (and 500 Cal/day extra gives weight gain). There must be research on the calorie level when these things happen on average.YobMod 08:18, 21 May 2009 (UTC)

This article [[2]] may point you towards the research that prompted your doctor's comments. Also see Adipose tissue#Visceral fat. It is reportedly harder to get rid of than the one stored in other tissue. When starting an exercise program or going on a diet a lot of excess water is often lost from tissues. This is frequently mistaken for "loosing fat". Miracle diet ads create unrealistic expectation as to how fast health weight reduction can be achieved. 71.236.24.129 (talk) 10:54, 21 May 2009 (UTC)

CO₂

The en:wiki (:en:Carbon dioxide) has for the meltingpoint of CO₂: -78.5 °C, the german de:wiki (de:Kohlenstoffdioxid) tells us it (called Schmelzpunkt) is: -56.6 °C.
The en:wiki states for the boiling point of CO₂: -56.6 °C, the german de:wiki gives for the same (called Siedepunkt) -78.5 °C.
Why did it go so wrong, and how to fix it? --VanBurenen (talk) 12:53, 20 May 2009 (UTC)

FWIW, Wolfram Alpha says the melting point is -56.56C and the boiling point -78.5 C. -- Aeluwas (talk) 13:05, 20 May 2009 (UTC)

When heating a solid first it will melt, then boil. Thus the boiling temperature has to be the higher of the two. The -56C is higher (hotter) then the -78C. So I think the en:wiki is (now) right and all the other wiki's (and Wolfram Alpha) are wrong... (Or I am nuts?) --VanBurenen (talk) 13:23, 20 May 2009 (UTC)

Don't ask me, I'm about as reliable as... uh, not sure what, today. I did think that it looked pretty odd when I wrote it, but I'm sure that's what Alpha says. I'm NOT sure that it's correct, on the other hand! -- Aeluwas (talk) —Preceding undated comment added 13:53, 20 May 2009 (UTC).

Under typical lab conditions (~1 atm pressure), solid CO2 sublimes directly to the gas at -78°C, and has no liquid form. Liquid CO2 only exists under certain pressure conditions, so separate melting/boiling points only make sense at high pressures. See File:Carbon dioxide pressure-temperature phase diagram.svg. I think the problem with the en:wiki article is that is uses "melting point" as a standard field, which is incorrect in this case. So the melting point given is really the sublimation point, and note the boiling point is given for a particular high pressure.YobMod 14:51, 20 May 2009 (UTC)

Hubble Propulsion

Greetings, giant brains! Please tell me where I begin to veer off course during the following series of postulates: A) The Hubble Space Telescope has a mechanism that allows it to change direction so that it can track pieces of the sky for long periods of time, and turn to other subjects when its ground-based masters desire. B) Since the Hubble cannot store years worth of propulsive material to eject and change direction, it must use forces generated by the movement of internal battery-powered mechanics to accomplish this trick. C) It is therefore possible to create a giant solar-powered, wing-flapping, bird-like spaceship to travel all over the solar system. No ejection of propulsive material required. Sappysap (talk) 13:28, 20 May 2009 (UTC)

Birds can use flappers because they push against air. In space there is no air. --VanBurenen (talk) 13:31, 20 May 2009 (UTC)

Like the song says, “In space there is no air / That's why we breathe it here” —Tamfang (talk) 23:32, 22 September 2019 (UTC)

Changing orientation is easy since it only requires a temporary change in angular momentum (which can be offset by an opposite temporary change in angular momentum in another part of the craft). Moving around (at least, moving further than the size of the craft) requires a change in linear momentum which cannot be offset by part of the craft, it needs to be offset by something leaving the craft (generally exhaust gasses from a rocket engine). --Tango (talk) 13:37, 20 May 2009 (UTC)

Hubble can't move itself from one place to another without propellant. It can ROTATE by moving its gyroscopes around. Gyroscope goes clockwise, Hubble goes counter-clockwise. And vice versa. You can't move around like that. (Sure you could throw the gyroscope out the back and the Hubble would move forward slightly, but then you'd just be using gyroscopes as propellant.) APL (talk) 13:51, 20 May 2009 (UTC)

You might be interested in ion propulsion, which can indeed create a great deal of thrust with only a little bit of ejected matter simply by ejecting it at very high speeds. --Sean 16:26, 20 May 2009 (UTC)

Hubble definitely uses gyroscopes - those can be powered from the solar panels. The basic idea is that if you spin a gyroscope's wheel in one direction - equal and opposite reaction means that the even bigger, heavier satellite spins in the opposite direction. With three sets of wheels at right angles - you can rotate in any direction. Hence, no (C) - sorry. You can use this trick to rotate a spacecraft - but to accelerate it bodily - you need some reaction mass. The faster you can throw the mass away - the less fuel you need - hence Ion drives which send a very small amount of material out at extremely high speeds. You could also use a solar sail - which uses light, bouncing off of a very large mirror as the 'reaction mass'. However, Hubble doesn't need anything like that. The little propellant it has left is being conserved in order that it can be used for its final de-orbit burn at the end of its life. SteveBaker (talk) 17:57, 20 May 2009 (UTC)

You might be interested, however, in the idea of solar sails. TastyCakes (talk) 18:03, 20 May 2009 (UTC)

Also, the emptiness of space is relative to what we are accustomed to, so the idea itself is not wholly empty. Consider the solar wind, but I do not think anybody has seriously entertained the idea of moving wings like a bird in outer space. As far as the Hubble goes, it is only the orientation of the telescope part of the satellite that Hubble manipulates with its gyroscope (not the location, which is in a fixed orbit), as SteveBaker has already essentially described.Julzes (talk) 16:11, 26 May 2009 (UTC)

Get a rotating office chair and a bowling ball. Put chair in center of room, self in chair and hold the ball. Keep your feet off the ground. Demonstrate that you can achieve B) rotary motion by swinging the ball. Try to achieve C) linear motion by any amount of flapping etc. If it's not possible in two dimensions it won't be possible in three dimensions. Cuddlyable3 (talk) 20:56, 20 May 2009 (UTC)

The trouble is that there is friction involved in the office chair scenario - and because you get different amounts of static friction than dynamic friction, you can move your arms slowly forward without the chair moving because of the high static friction - then fling them back violently and move forwards a few inches. This process can be repeated as often as needed to propel oneself around the room. However, in the almost fictionless environment of space - this trick doesn't work. SteveBaker (talk) 01:42, 21 May 2009 (UTC)

The engineer Eric Laithwaite thought he could use gyroscopes for reactionless propulsion, but other scientistis seem to think he was mistaken. 89.242.85.248 (talk) 19:38, 22 May 2009 (UTC)

See also Norman Dean. —Tamfang (talk) 03:29, 25 May 2009 (UTC)

Setup to play music in apartment

I am looking for a way to listen to music / podcasts in multiple locations in my apartment. All my music / podcasts are on my PC - in my old place I could hear the music from the speakers next to the PC anywhere in the apartment, but in my new (bigger :) ) apartment the PC sits at one end of the apartment, so as soon as I enter another room I can no longer hear it.

I am willing to lay down some cables, but wireless solutions would be wonderful (especially as the distance from my PC to the kitchen would be a good 25-30m of cable, to go around doorframes etc). I would love to have sound in two locations (in addition to the speakers next to the PC).

I have thought about just taking the audio signal from my PC and running it through some y splitters and feeding it to multimedia speakers which I would install in the other rooms. Unfortunately, this involves wiring (a lot of it, I'd have to run wires from my PC to two locations), and I'm not sure what splitting the signal like this (not to mention the 25m of cabling!) would do to the sound quality. I have also thought about feeding the signal to an amp, which would then output to two independent sets of stereo speakers - but, again with the cabling, and some cursory shopping around has revealed no amps with several speaker outputs, does this even exist? Lastly, a colleague has mentioned using some kind of internet radio, which would listen wirelessly (over my WLAN) to a stream from my PC, but I don't know where to start with such an idea.

What would be good solutions that I should look at? Any pointers would be appreciated! — QuantumEleven 15:24, 20 May 2009 (UTC)

Wireless devices specifically intended for this do exist. A quick bit of googling found this, but I make no recommendations. I believe there are various such devices on offer, so you'll need to do your own research to find what is right for you. --Tango (talk) 15:58, 20 May 2009 (UTC)

Apple's Airport Express allows wireless streaming of iTunes music. You can download add ons that let the system stream other things - Airfoil I think is one of the products. I personally have an Airport Express and it works really well for linking your iTunes up to another set of speakers - and with my laptop on the network I can use that as 1 (admittedly giant) remote control for my stereo. I must warn, however, that user reviews on the product have been mixed with many reports of the product dieing after a year or two. ny156uk (talk) 16:27, 20 May 2009 (UTC)

I dont' know if this is what you have in mind, but if you would be happy playing it through your television/whatever speakers are hooked up to your television, I bought a WDTV this weekend and have been very happy with it. You plug in any kind of USB drive and it'll play it on your television over composite or HDTV cables. It's primarily for playing computer videos on your tv, but it will play mp3s (and pictures) as well. The only problem (for music) is it doesn't seem very good at splitting up by album: you have to go by artist or folder, and then it gives the files in those folders by alphabetical order. I'm not sure if it can play playlists... Also it doesn't have a network card. You could conceivably hook up a networked drive to it (such as the My Book World Edition) but it probably makes more sense to just put all your music on a separate hard disk and attach it. I got one for $150 Canadian at Best Buy, on Amazon they are $105 US.TastyCakes (talk) 16:56, 20 May 2009 (UTC)

This inexpensive gadget is a tiny FM transmitter that plugs into the sound output of your PC. Then you can hear the sound on any FM radio within range. Cuddlyable3 (talk) 20:43, 20 May 2009 (UTC)

If you don't mind headphones you should get a pair of decent wireless headphones. I love my Sennheiser HDR-130, super comfy with good sound quality, but tend to fall down at the slightest tilt from my head (so far it has survived what, 50 1.8m drops?). --118.90.137.39 (talk) 04:58, 21 May 2009 (UTC)

My suggestion is a receiver with a multi-room output. This mean that you will plug 2 (or more, but 2 is common) pairs of speakers into the receiver, and then you can choose which of the pairs are on at any given time, regardless of the signal coming in (you can have none, either or both on at a time). I have this set up at my house: My iPod plugs into the receiver, and I can listen to it in my basement. If at any time I want to walk into my backyard and keep listening, I can hit the zone 2 button on my receiver and the outside speakers will turn on and mirror what's playing while the music continues in my basement. This also fixes your costly wiring problem, since you just need 2 speaker wires for each pair, and speaker wire is generally pretty cheap if you get it in bulk. I would stay away from many wireless devices, ESPECIALLY those fm radio transmitters, because the quality is horrible, which really really bothers me (but if you don't mind horrible sounding fuzzy music than that's the easiest solution). -Pete5x5 (talk) 16:07, 21 May 2009 (UTC)

• I've been successful before in installing an audio driver that allows you to transmit audio output over Ethernet from one PC to another. I combined two programs, one that allows you to digitally redirect a virtual audio output back into a virtual audio input channel (you can also do this with a 1/8" male-male cable and your speaker output/mic in), and one that allows mic input to be broadcast over a LAN. Combine this with standard wireless Ethernet and cheap netbooks, and it's quite easy to get audio from one place to another. Dcoetzee

Human Skulls

Do people with different face shapes have different shaped skulls? Or is the difference made by skin, muscles and cartilage? —Preceding unsigned comment added by 82.44.54.169 (talk) 16:59, 20 May 2009 (UTC)

See Forensic facial reconstruction. The skull, otherwise they wouldn't have much hope doing it. Dmcq (talk) 17:18, 20 May 2009 (UTC)

Well, I think it is a combination of factors. I agree that the skull does play a significant role. I remember when I was reading about the first face transplant the doctors saying the recipient would end up with a face that is somewhere between their old face and the donor's face since they kept the same bone structure but got new skin, etc. --Tango (talk) 17:44, 20 May 2009 (UTC)

The bones make an enormous difference. The triangle formed by the eyes and mouth are essential in both natural and machine facial recognition, and that triangle is determined almost entirely by the skull. If the skull wasn't a big deal, you could put facial prosthetics on a person to make them look just like anyone larger than themselves, but that's just not the case -- Mission Impossible to the contrary. --Sean 17:49, 20 May 2009 (UTC)

Cartilage and soft tissue attaches to bone at some points and vessels feed through holes. There used to be a saying in paleontology that the fossil of an Elephant would be reconstructed to look like a Hamster because the soft tissue didn't leave a trace. This has been changed with the more recent developments in the field where similarities in fine bone structure of (recently dead) living creatures is compared to pits and holes and attachment ridges left in the fossilized bones. Bone is not a stable structure. It grows and cells get replaced. Soft tissue differences leave a trace on the bone. 71.236.24.129 (talk) 07:08, 21 May 2009 (UTC)

All the tissues impact the appearance of the face. Notice that if a person gains or loses a lot of weight, the appearance of their face changes substantially, without their bone structure changing - this shows that the face isn't determined entirely by bone structure. Dcoetzee 10:46, 21 May 2009 (UTC)

mt doom

I am drawing a satirical comic parodying Lord of the Rings. Basically Sam and Frodo get into a fight at the top over who has to buy the beer back at the Shire and Frodo gets pushed in. I need to know if it is likely that his hair would catch fire before he hits the lava, assuming hobitts have a similar terminal velocity and hair burning properties as humans would and that the fall distance to the lava is sufficient to achieve terminal velocity. 65.121.141.34 (talk) 20:17, 20 May 2009 (UTC)

Does it really matter? Dauto (talk) 20:47, 20 May 2009 (UTC)

Hair won't catch on fire because of the free fall itself. Terminal velocity for a flailing human is too slow - it won't generate enough friction, as evidenced by all the skydivers which reach terminal velocity without catching fire. In the absence of a spark, you need to get a substance to the autoignition temperature in order for it to catch fire. I couldn't find a figure for the autoignition temperature of hair, but for paper it's around 450 F (230 C - although some sources claim it's higher, around 840 F/450 C. It of course depends on the type of paper, etc). Lava can get up to 2,200 F (1,200 C), so it might be reasonable to claim that at some point above the lava the temperature reaches the 450-840 F range for autoignition of paper. If hair's autoignition temperature is similar to paper, hair should spontaneously ignite at that point. How long it'll be on fire will depend on how far away from the lava the temperature reaches the autoignition temperature. But a satirical comedy featuring hobbits in a magical universe probably can take some license with the facts ;-). -- 128.104.112.117 (talk) 20:50, 20 May 2009 (UTC)

Did you get the 450F from Fahrenheit 451? TastyCakes (talk) 20:54, 20 May 2009 (UTC)

I actually got it from averaging and rounding the 424-474 F range listed in the autoignition temperature. But I knew about Fahrenheit 451 - in fact footnote 1 in that article is where I got the "some sources claim it's 840 F" info. -- 128.104.112.117 (talk) 15:56, 21 May 2009 (UTC)

True, I don't think my crazed LOTR fan friend is too big into real science anyways. 65.121.141.34 (talk) 20:53, 20 May 2009 (UTC)

Things that one need to know about are where to find food, water and shelter. But flaming hairy hobbits? Cuddlyable3 (talk) 21:04, 20 May 2009 (UTC)

Have you read Bored of the Rings? -Arch dude (talk) 01:43, 21 May 2009 (UTC)

Draw whichever you think is funnier. DJ Clayworth (talk) 18:06, 22 May 2009 (UTC)

Professional sport gamblers

Is it possible to be good at sport gamble or is it just good luck? Since a player is competing against the mob and the mob is always right, is it possible?--88.6.117.202 (talk) 20:52, 20 May 2009 (UTC)

The "mob" isn't always right. The odds are based on what the mob thinks is likely to happen, if you know more than the mob then you can profit (consistently - anyone can profit inconsistently with just luck). You usually can't know more just by being clever, you need better sources of information. If you have contacts involved in the sport feeding you information (eg. "so-and-so's injury is worse than they're making out, he probably won't last the whole match") you can get an advantage. Personally, I prefer to gamble on things where I can increase my own chances using skill - eg. poker. --Tango (talk) 21:13, 20 May 2009 (UTC)

Umm, regarding the above tantalizing comment, and this little tidbit and reviewing Poker, Betting (poker) and Bluff (poker), I think there is an article opportunity here: Poker, how to play intelligently. Sorry about the short notice but I just saw your comment and thought that with all of the trivial articles we have around here that this one would stand as non-trivial, for sure. I think that you've got something to add but, that's just a guess. Ya think? -hydnjo (talk) 03:14, 21 May 2009 (UTC)

Wikipedia is not a how-to guide. There are plenty of websites offering tips on how to play poker, many of them are quite good (for a complete beginner wanting to get good enough to win money off their friends, you would need something a bit more than google to learn how to win major tournaments). --Tango (talk) 14:51, 21 May 2009 (UTC)

How many such tips are poisonously wrong? —Tamfang (talk) 03:35, 25 May 2009 (UTC)

Like the stock-market, there are a few anomolies, but in reality it is unlikely to be worthwhile. See the efficient markets hypothesis. Sports gambling is a kind of market, and a lot of academic research by economists has been done. Anomolies include the favorite-longshot bias. It used to be possible to sometimes exploit the tote in the past, but the rules have been changed. You might in theory be able to develop a handicapping system that gave you a small advantage over chance. But, if you are smart enough to be able to do all this, then you would certainly be able to earn far more money doing something else. In reality, you will almost certainly lose money in the long run. 78.146.198.122 (talk) 21:17, 20 May 2009 (UTC)

Wouldn't consistently losing money be just as hard as consistently winning? — DanielLC 05:02, 21 May 2009 (UTC)

The house gets a cut, the vig. If someone bets randomly on sports, over time that will erode his capital down to nothing. Dragons flight (talk) 05:30, 21 May 2009 (UTC)

The trick is always to exploit inefficiencies in the market. In this case, the fact that not everyone has the same information. --Tango (talk) 14:51, 21 May 2009 (UTC)

You could search the bookies for Arbitrage (spelling) opportunities whereby you bet on all outcomes and are guaranteed a (usually small) win. E.g. A league football (soccer) game has 3 outcomes. Home win, draw, home loss (or away win if you prefer). If site X has odds of 4/1 for home win, site Y has odds of 4/1 for the draw and site Z has odds of 4/1 for home loss you can put money on all possible outcomes and be guaranteed a return. These sorts of situations will occasionally come up but given the difficulty and effort of finding (and taking advantage) of them they're not really viable as a 'pursuit'. Lots of betters will use statistical tactics to hedge bets and reduce down their odds of losing, whilst trying not to reduce the value if they do win. Professional Gamblers certainly do exist, I know one. I don't know what you mean by the mob but bookmakers certainly arrange their odds so that they win regardless of the event outcome. ny156uk (talk) 21:40, 20 May 2009 (UTC)

In fact we have an Arbitrage betting article, guess that's worth a read! ny156uk (talk) 21:41, 20 May 2009 (UTC)

Tango means that the odds you can get (or the line) depends on the alleged wisdom of crowds. If the Patriots are favored by 8 points over the Rams, and masses of bettors ("the mob") put money on the Patriots, then, as Ny156uk implies, the bookmakers will adjust the odds so that the Patriots are favored by 8 and one-half points, and then by 9, and so forth until the betting is roughly equal on both sides, so the bookmaker is finally sure to profit no matter who wins because he's only paying out $10 for every $11 that was bet (or so).

To answer the original anon's question, it's possible to win, yes, which can be illustrated easily if you consider illegally bribing players or referees, which certainly has happened many, many times. Unfortunately I don't know any references that discuss how many people are able to do this (more legally) for a living. Tempshill (talk) 22:35, 20 May 2009 (UTC)

Yes, one of the most effective ways of getting more information than the "mob" is to bribe people so you have a key piece of information others don't have - that so-and-so is going to throw the match. --Tango (talk) 14:51, 21 May 2009 (UTC)

Here it's necessary to distinguish two common senses of 'mob' ! —Tamfang (talk) 03:37, 25 May 2009 (UTC)

When you are thinking of placing a bet of any kind, it is wise to consider the multi-billion dollar casino the "house" has managed to build - and how they raised the capital to build it. The stakes are always against you; the Bellagio didn't get built by having the odds in your favour, right? Matt Deres (talk) 01:46, 21 May 2009 (UTC)

For random games, like roulette, that is absolutely correct. There is no way to win at roulette other than getting lucky (or cheating!). The results of a horse race aren't random, though, which opens up possibilities. --Tango (talk) 14:51, 21 May 2009 (UTC)

You can win at horse racing if you base your bets on the speed of each horse rather than its form. AFAIK horse speeds are not published (presumably because that would spoil the fun), and you have to work them out for yourself. But this does work; success has everything to do with spending a few hours on your homework and very little to do with luck.--Shantavira|^{feed me} 08:20, 21 May 2009 (UTC)

The speed of a horse is not constant, otherwise you would just have to go through results for the last few weeks and find out which horses in the race you are betting on have beaten which other horses in the race previously. You don't need much of an advantage to get profitable in horse racing, the house edge isn't particularly great. It doesn't matter if you lose the occasional bet, as long as you win more than your lose. --Tango (talk) 14:51, 21 May 2009 (UTC)

I sometimes get junk mail about horse racing betting systems - where for a large subscription you get sent betting tips which have been produced by some secret system. Is there an article about thse? I'm confident that such systems do not work, but I'm curious about what the secret system may be. Similarly with other secret money-making schemes that I also get sent junk mail about. 78.146.67.27 (talk) 12:16, 21 May 2009 (UTC)

The secret system will just be a load of nonsense, if you receive anything at all after giving them your money. It is obviously a scam because anyone knowing such a system could make far more money just using it themselves than they could make selling it. --Tango (talk) 14:51, 21 May 2009 (UTC)

One "secret system" (which a sometime-gambling friend once experienced) works as follows (numbers are for example only). The scammer identifies by adverts or otherwise 400 receptive gamblers (unknown to each other), and sends each a free "exclusive" prediction of the outcome of a race. If there are 4 horses in the race he'll send 100 a prediction of horse A winning, 100 horse B and so on. After the race, 100 will think he called it correctly. He then repeats the process with another race (perhaps for a small fee), then another (for a larger fee), until he's got about 6 marks who think he really knows his stuff. Now he offers to sell them the next "prediction" either for a fairly hefty sum, or on the condition that they put on a sizeable additional bet on his behalf, or both. Assuming they fall for it, he's assured of 6 hefty fees, and/or the proceeds of at least one large winning bet that he didn't have to stake. I'm glad to say that my friend figured out the scam before committing himself to the last step. 87.81.230.195 (talk) 23:58, 21 May 2009 (UTC)

See Derren Brown, The System. 89.168.85.22 (talk) 10:32, 22 May 2009 (UTC)

Ah! An interesting corroboration I was unaware of as I avoid most TV. FWIW, the experience I recounted occurred around 1980, but I'm sure the method (or System) has been around for a lot longer. 87.81.230.195 (talk) 11:42, 22 May 2009 (UTC)

Early primate Darwinius shown at keyboard?

Why does our supposed ancestor, "Ida" Darwinius,

look like she is sitting and working at a keyboard? Edison (talk) 21:17, 20 May 2009 (UTC)

This?Popcorn II (talk) 21:32, 20 May 2009 (UTC)

She seems to have better posture, and a shorter tail, in photo number 2. Edison (talk) 22:49, 20 May 2009 (UTC)

Ya, and at the moment, she is trying to google why she is suddenly so famous after 47 million years. More than that she is surprised at why her food is taking so long to digest. Unfortunately she cannot write anything in her own article at Wikipedia because of conflict of interest. But expect a question or two here at refdesk in few days maybe, because she will know many more startling things about herself in coming days and more temptation to come and ask here. - DSachan (talk) 23:10, 20 May 2009 (UTC)

Then does WP:BLP apply? We would not want to embarrass her. Computer geeks have feelings, too. Edison (talk) 04:57, 21 May 2009 (UTC)

She's waiting for 999 Shakespeare-loving friends to show up? Clarityfiend (talk) 05:34, 21 May 2009 (UTC)

On a more serious note: Rigor mortis may help explain some of the position of the limbs. The creature was using Arboreal locomotion. When in pain or near death many creatures curl up in a near fetal position. Humans tend to recognize known images in non related visual input (google "Face on Mars" "Devil in the smoke") Evolutionary this enabled us to recognize hidden predators. But sometimes a primate fossil is just a primate fossil.71.236.24.129 (talk) 06:57, 21 May 2009 (UTC)

We have an article for spurious pattern recognition by humans: pareidolia. Dcoetzee 09:31, 21 May 2009 (UTC)

They laughed when she sat down at the piano. Deor (talk) 11:56, 21 May 2009 (UTC)