Wikipedia:Reference desk/Archives/Science/2007 December 3

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December 3

Skin Tightening

I lost about 50 pounds over the last 8 month and I was wondering how long it takes for your intestines to shrink (someone was telling me they shrink after you lose weight) and also for my skin to tighten up. It doesn't look loose, but I heard it tightens up even more. —Preceding unsigned comment added by 76.167.132.90 (talk) 01:36, 3 December 2007 (UTC)

I imagine it would depend on a lot of factors, none of which anyone here could judge from one post on a forum. Skin elasticity varies wildly from person to person, a major factor however would be how old you are, the older you are the more elasticity your skin loses. Also how much sun exposure you have had would be another factor, and for how long and how much larger you were before you lost weight, all these things will vary how much and how quickly your skin will shrink back. Also, i've never heard of intestines shrinking, if they do I doubt you would notice it, you'd probably be better of discussing these things with your GP when you next visit. Vespine 03:03, 3 December 2007 (UTC)

Langmuir adsorption isotherm

Which would obey the Langmuir adsorption isotherm better, metal cations or organic compounds?

Thanks so very much! —Preceding unsigned comment added by 134.82.109.58 (talk) 03:31, 3 December 2007 (UTC)

It would depend greatly on the material its being adsorbed onto so it hard to compare the two. But I suspect it would be organic molecules as the cations (depending on concentration) can create a electrical double layer on the surface thus inhibitng further adsorption. Shniken1 03:54, 3 December 2007 (UTC)

advanced technologies

may i know about some advanced technologies in electrical and electronics for presentation purpose?202.88.234.134 09:03, 3 December 2007 (UTC) —Preceding unsigned comment added by 202.88.234.134 (talk) 08:58, 3 December 2007 (UTC)

You might want to look through the categories at the Electronics Portal and the Technology Portal. --Milkbreath 11:50, 3 December 2007 (UTC)

dreams

may i know whether blinds are able to see dreams?if yes is there any colours in there dreams?what happen to the persons whom became blind during their life..is they saw any dreams?202.88.234.134 09:18, 3 December 2007 (UTC)also can animals are able to see dreams?202.88.234.134 09:18, 3 December 2007 (UTC)

Dreams are based on your memories (real and imagined). People who were born blind won't see in their dreams. People who became blind during their life may see in dreams. Similarly with colors, sounds, and so on. If you remember them, you can dream about them. And yes, animals dream. With a cat, for example, you will see its paws moving as it presumably dreams about fighting. --Anonymous, 09:40 UTC, December 3, 2007.

No, Blinds cannot see dreams, since they are simply inanimate window coverings, with no cognitive functions. -- JSBillings 14:04, 3 December 2007 (UTC)

Making fun of the OP's phrasing of the question is rude and uncool. Please stop doing that. SteveBaker 20:09, 3 December 2007 (UTC)

Here is an academic critique discussing this very question. Rockpocket 18:55, 3 December 2007 (UTC)

Thank you so much for that article link, Rockpocket!! This happens to be something that I've wondered about for many years - apecifically, what people who are completely blind from birth dream about. I thought I'd provide a brief abstract of the article for those who don't wish to wade through it. I found it very interesting to read how people who have been blind from birth have the ability to "see" their surroundings in their minds through other senses (mainly touch) other than sight, and that they then construct three-dimensional imagery in their minds to accompany their perceptions. They also can draw two-dimensional images of a three-dimensional object quite accurately. However, as the article noted, these people have difficulty with being able to perceive that there would be differences in color or brightness levels. The article reported how there is a distinction between a person's visual image (what a blind from birth people "sees") and visual content (what people who can distinguish between color and brightness sees). The article also said that the part of the brain that functions when someone who is sighted is seeing is also the same part of the brain that is functioning when a blind person is "seeing" through touch. So when people who have been blind from birth dream, they do dream in the third dimension about images of things, but they have difficulty with color and brightness of objects. Absolutely fascinating! Saukkomies 14:18, 8 December 2007 (UTC)

Since people are animals it is reasonable to assume that other animals dream. It is not reasonable to supoose that because a cat twitches it is dreaming, unless you also twitch when you dream. I don't (apparently). I would be more convinced by observations of REM in animals.--Shantavira|^{feed me} 19:54, 3 December 2007 (UTC)

If you ever watched a dog sleeping - you can see coordinated twitching of paws plus (sometimes) tiny little yelps of barking, sniffing, ear twitching and small movement of the jaws. You can easily follow the 'plot' of the story they are dreaming out. It's impossible to believe that they aren't dreaming of running and chasing something. I can't say that I've noticed REM - but dogs don't rely on their eyes much - so it's perfectly possible that they don't exhibit this sign - using RPM ('rapid paw movement'!) instead. SteveBaker 20:09, 3 December 2007 (UTC)

Dogs display REM when they dream, just like humans do. Consider poor Dreyfus. Rockpocket 23:57, 3 December 2007 (UTC)

Viruses are all around us?

This is a continuation from a previous question. Are there viruses all around us, even right now? Someone insinuated that the cold virus is one of the viruses all around us constantly, and we can get it from the enviroment without actually being near someone who is already infected. They also insinuated that he reason why we don't get the cold despite it always being around it, is due to our immune system. I find this hard to believe though because the cold virus is an RNA virus, and thus, it would be highly unlikely to be immune to the particular strain that happens to be around us. Can we catch a virus from the enviroment alone, simply by breathing the air, without being near someone who is infected? 64.236.121.129 18:41, 3 December 2007 (UTC)

In principle, yes. In practice, it's fairly unlikely. It's all a matter of probability -- the probability that the virus is sufficiently concentrated, that it's not gone inert/dead/whatever by being outside a host, and so forth. — Lomn 19:14, 3 December 2007 (UTC)

You should be careful when talking about things like "the cold virus". There are hundreds, probably thousands, of different coronaviruses and rhinoviruses that we all describe as causing the "common cold" when we get sick from them. Even if you gain immunity to one of them, there are still plenty of others your immune system will not immediately recognize.

As for your main question, yes, there are viruses around us constantly, but that's because all life can be infected by viruses, even bacteria (see Bacteriophage). This means that the wind blowing past your home carries viruses from all sorts of organisms, though in very tiny quantities, and smaller quantities means a smaller risk of infection. Also, the innate immune system can sometimes deal with viruses never encountered before, so if there are only a few viruses they may not survive long enough to become a full-blown infection. Besides that, most viruses can only flourish in a few specific genera, which means that you're probably safe from most viruses you encounter. Also, those viruses in the environment tend not to live very long, especially in sunlight, because UV light, oxygen, and other such things kill most viruses rather quickly. All of that means that, yes, you can get infected with a virus when "isolated" from other people because you're not actually totally isolated (unless you're somewhere like Antarctica), but your odds of infection are extremely small. Also, you never get a virus "from the environment alone", you're getting it from some other organism who was infected with it and spread it into the environment fairly recently. So, if you see someone who is sick from a virus, the odds are way more likely that they got it from close contact with someone (or something) else that was infected, and not from long-distance "environmental" contact. -- HiEv 21:04, 3 December 2007 (UTC)

There's some new research about the persistence of influenza virus in the environment. -- Coneslayer (talk) 12:16, 5 December 2007 (UTC)

Here's a version of that link so you won't have to login to read it: "Study shows why the flu likes winter". The short version is that the flu viruses survive longer outside of the body in cold, dry air, and the body also releases viruses longer in a lower temperature environment. Increasing the temperature or the humidity reduces the odds of transmission, with 30°C (86°F) or 80% humidity being about the limit the viruses can function in. The optimal environment for the viruses was about 5°C (41°F) and 20% humidity. So, in cold, dry environments you're likely to be exposed to more viruses at once, which increases your odds of getting sick, and more people getting sick increases the odds of other people getting sick. However, I was kind of disappointed that the article didn't mention the lengths of time the viruses survive outside the body in the different environments. -- HiEv 15:46, 5 December 2007 (UTC)

So it is a fact that viruses can exist outside of an organism, and in cold temperature, the flu virus can exist outside of an organism for longer periods of time. But what about the common cold? Does it also live longer outside of an organism for a longer period of time in cold temperature? 64.236.121.129 (talk) 17:26, 5 December 2007 (UTC)

giardia/mitochondria

Given that Giardia lack mitochondria, how and where do they create energy/ATP?75.42.65.119 19:20, 3 December 2007 (UTC)

Like most protozoans (all of which lack mitochondia), Giardia can produce ATP by glycolysis. I'm not an expert, but one will probably come by in the next hour eventually. Nevertheless, our article on glycolysis should get you started and feel free to ask additional questions if you have any. (EhJJ) 19:35, 3 December 2007 (UTC)

Actually, only a few protozoa lack mitochondria. According to eukaryote, The few protozoa that lack mitochondria have been found to contain mitochondrion-derived organelles, such as hydrogenosomes and mitosomes. These mitochondrion-derived organelles do some of the work normally performed by mitochondria. --mglg_(talk) 00:02, 4 December 2007 (UTC)

I need to make sure I drink coffee before posting to the Ref Desk. In any case, prokaryotes do not have mitochondria and survive just fine. Although Giardia is not a prokaryote, it could use similar mechanisms if it lacks mitochondria. Sorry for the confusion. (EhJJ) 15:34, 4 December 2007 (UTC)

Keep in mind that mitochondria were most likely once separate organisms. In the beginning, no life used mitochondria, but some organisms developed a symbiotic relationship that evolved into the cell+mitochondria system we see in most life today. See the Endosymbiotic theory article for details. However, just because that system is common today doesn't mean that it's the only way life can survive. -- HiEv 04:11, 4 December 2007 (UTC)

The main ATP producing process comes from the electron transport chain. For eukaryotes, the process occurs in the mitochondria. For prokaryotes, it occurs in the cytosol.128.163.224.222 (talk) 21:50, 4 December 2007 (UTC)

Dry hands, lips

I just moved into a place and at night time I have very dry hands (put cream on it a couple times until I fall asleep), I wake up from having a dry throat and I am thirsty, and my lips are chapped. Would a humidifier help with these symptoms? Any suggestions? Thanks

There is probably no connection between your symptoms and the move. Please consult a doctor.--Shantavira|^{feed me} 19:57, 3 December 2007 (UTC)

I would not entirely discount the effect of the move. If the move was to a new, drier climate, it could have such effects. Also, differences in the HVAC system could also affect the indoor humidity (for example, some furnaces have humidifiers, and others don't). -- Coneslayer 19:59, 3 December 2007 (UTC)

To add to what Coneslayer said - simple, inexpensive hygrometers exist which will measure the humidity in the air. Taking a reading would show if your environment falls outside the "normal" zone. A humidifier would help put that back into the normal humidity region. We can't say if that would help your chapped hands/lips/throat, as there may be an underlying medical condition behind it. To rule that out, you would need to see a doctor. -- 20:09, 3 December 2007 (UTC) —Preceding unsigned comment added by 128.104.112.21 (talk)

Yes, a new place is very likely to be less humid, and if so a humidifier will help. Since you might have a medical condition, we are required by our policy to recommend that you consult your doctor: Please do so, because there are all sorts of nasty thinks with thees symptoms. Furthermore, even if the problem is actually a humidity problem, the dryness may have caused a medical problem that will require treatment DO this even thoug you may end up getting advice from your doctor to install a humidifier. OK, If you decide to add a humidifier, do some quick research first. If your dwelling has forced-air heat, a plenum humidifier is a good choice, but if you live in a "hard-water" area, do not add a pulse humidifier, as it will generate what is effectively chalk dust. However, a plenum wick humidifier should be periodically cleaned to avoid nasty things growing in your air handler. -Arch dude 00:53, 4 December 2007 (UTC)

Products such as Chapstick or other lip balms can reduce the unpleasantness of chapped lips. Humidifiers of various sorts add moisture to the air. See also Consumer Reports for discussion of humidifiers. A forced air furnace humidifier may stop working for a variety of reasons, such as a blockage in the water supply tube or an electrical problem, or simply a turned off supply valve or a humidity control set too low. Cheap hygrometers may be more decorative than informative. Accurate ones such as art conservators or heating repairmen use are fairly expensive. A science buff can use dew point measurement combined with temperature measurement, or wetbulb/dry bulb measurement to determine relative humidity. I concur that the sudden onset of recurring thirst and other symptoms listed is better discussed with your doctor than with contributors to Wikipedia. Edison 02:56, 4 December 2007 (UTC)

If your old home used radiators, and your new home uses forced air heating, that would cause a major decrease in the humidity of the air you're exposed to. Unlike with radiators, forced air heating is known to produce often uncomfortably low humidity. I guess we're probably supposed to say "consult with a doctor" in this case, but to me, getting typical symptoms of exposure to low humidity at the exact same time as a move seems unlikely to just be a coincidence. Yes, humidifiers relieve the symptoms due to the low humidity caused by forced air heating. Getting the humidity back up to a more moderate level is also easier on any wood furniture like a piano that you may have. MrRedact 04:59, 4 December 2007 (UTC)

I'm very skeptical about the statement that forced-air heating produces lower humidity. The relative humidity is a function of the temperature and the absolute humidity. Presumably the selected temperature will be the same in either case and the heating process will not affect the absolute humidity, so why would there be a difference? --Anon, 05:11 UTC, December 4, 2007.

The difference is due to imbalances and leaky ducts in forced air systems causing negative air pressure in the house, which causes outside air to get sucked into the house.[1] Although the relative humidity of outside air in the winter is comparable to that in the summer, it has a low absolute humidity due to the cold temperature. When that outside air gets sucked into the house and then heated up, that results in a low relative humidity indoors. Radiators don't have that problem, because they don't affect the air pressure inside the house, and hence don't cause outside air to get sucked inside. MrRedact (talk) 23:42, 4 December 2007 (UTC)

"But only if they are improperly installed in leaky homes", says your link. Okay, that way it makes sense. Thanks. --Anon, 06:17 UTC, Dec. 5.

Also be careful with humidifiers. If you don't get it right they can cause condensation and destroy electronics and cause electrical fires.--Dacium 03:56, 4 December 2007 (UTC)

Warm air heating (along with many other types of mechanical ventilation systems) are often noted for causing dry air. This can be overcome by installing a humidifier, however a lot of systems were either designed without humidification equipment or had that equipment turned off or removed because of fears about leigonella bacteria which thrive in warm conditions where there is standing water. The risk of this can be eliminated by heating the water to above 60c or treating it with an antibacterial agent. A Steam Humidifier boils the water which effectively prevents any bacteria from breeding, however these solutions are all expensive and may not be applicable for your individual situation. 62.249.220.179 16:53, 4 December 2007 (UTC)

Assuming that you live in the Northern Hemisphere, the air might just be less humid everywhere due to colder temperatures. sh¤y 21:53, 4 December 2007 (UTC)

Sugar in Soft Drinks

Hello I was just wondering what would be the best chemical indicator for testing the amount of sugar in soda the result only needs to be a qualitative measurement i have thought of using Glucose oxidase, (the chemical used in glucose meters that changes color depending on the amount of glucose present.) or a isotope of Potassium. Any and all thoughts on this subject are welcome. thank you —Preceding unsigned comment added by 76.100.154.203 (talk) 20:28, 3 December 2007 (UTC)

Since soft drinks are mostly sugar and water and you only need a rough estimate ("qualitative"?), evaporating the water would show the amount of sugar. Icek 02:17, 4 December 2007 (UTC)

Sugar is both hygroscopic (adsorbs water) and polymerizes with heat (turns into caramel), so I'd guess that evaporation would be a very inaccurate way to determine sugar concentration. Delmlsfan 02:49, 4 December 2007 (UTC)

All advice which follows is anecdotal and should not be depended on if economic, safety, or health consequenses attend. Soft drinks sweetened with sugar are denser than soft drinks of the same manufacturer and flavor sweetened with Nutrasweet or other artificial sweeteners, in general. Thus density is a physical (sorry, you asked for chemical) measure of whether the pop is sugar or artificially sweetened. Freezing point is another physical measure: in my experience, artificially sweetened pop freezes at a higher temperature than similar sugar pop. Sugar pop is said (note the weasel words) to test higher with strips and meters used by diabetics for determining blood sugar. Strips useed for testing for sugar in urine are a closely related possibility for "qualitatitive" analysis of sugar in soda pop. Edison 02:44, 4 December 2007 (UTC)

To get around both of those problems, you could evaporate most of the liquid off, then treat it with strong sulfuric acid (we're talking the concentrated laboratory kind here), which converts carbohydrates to water and pure carbon. Let the carbon dry and take the mass, and you should be able to calculate the amount of sugar you had. (This is based on a fairly well-known chemistry demonstration.) sh¤y 21:56, 4 December 2007 (UTC)

One difficulty you would have is that soft drinks are usually sweetened with high-fructose corn syrup. Although partly glucose, there is also a large amount of fructose, which will be poorly oxidized by glucose oxidase (more properly an enzyme, rather than a "chemical"). Note that glucose oxidase, by itself, won't produce any sort of visible color. It produces hydrogen peroxide, a colorless chemical which can be detected by another enzyme (horseradish peroxidase) and a colorimetric reagent. To detect the fructose in addition to glucose, you can also add in a glucose-fructose isomerase, but the only one I'm aware of that might help is Glucose-6-phosphate isomerase, which requires fructose-6-phosphate, not just fructose. You would have to add in Fructokinase and ATP to the reaction mix as well. Also be aware that some soft drinks (particularly those made outside the US) contain sucrose (table sugar) as a sweetening agent, rather than HFCS. To use glucose oxidase on those, you would need to add Sucrase to the reaction to break the sucrose to glucose and fructose.

As an alternative, you can look for alternative sugar assays. Tollens' test, Benedict's test, Fehling's test, the Nelson-Somogyi assay, and the DNS assay are popular choices, but there are dozens in the scientific literature. These tests can detect both glucose and fructose without enzymatic conversion. One problem with these assays is that they tend to have different responses to the different sugars, so you would need to know the approximate ratio of glucose to fructose. Also, they tend to be unresponsive to non-reducing sugars, so they may not detect sucrose without prior hydrolysis.

Probably the best way to determine the sugar composition of an unknown sample is using chromatographic techniques like HPLC. They sell special columns specially designed for carbohydrate analysis [2].

Regarding the evaporation-then-weigh, note that carmelization tends not to happen until over 100 C, so if you heat gently, you may be able to drive off water, and avoid decomposition of the sugar. If you have access to a lyophilizer, that would work even better. Note that both glucose and fructose have the same molecular weight. - I'm not sure what you thought of doing with the potassium isotope, but I doubt that it would work. -- 21:44, 5 December 2007 (UTC)

list of various maps per country

I came across a list of all the countries of the world and it included many various types of maps. But, I lost the link and have looked and looked and cannot find it again. Does anyone know the link? —Preceding unsigned comment added by 66.136.99.246 (talk) 21:09, 3 December 2007 (UTC)

I don't know specifically which list you are referring to, but I bet it can be found in Lists of countries. Rockpocket 21:45, 3 December 2007 (UTC)

Perhaps you are referring to the CIA Factbook maps? (EhJJ) 22:30, 3 December 2007 (UTC)

For almost any kind of map, my first stop is the University of Texas' Perry-Castaneda collection at http://www.lib.utexas.edu/maps/ -SandyJax 19:13, 4 December 2007 (UTC)

There are a lot of map collections linked from our Map article. 152.16.59.190 (talk) 04:38, 6 December 2007 (UTC)

Salt Water Pool Levels

In a salt water pool it is typically 3,000ppm salt, which enables the chlorination to typically produce about 3ppm chlorine. As the salt level drops, the water conducts less and electricity does not flow across the cell as well and less chlorine is produced. Is this likely to be a linear or exponential decay? My pool has dropped to 0.5ppm chlorine, I was wondering if there is anyway to know the salt level? Would it be 500ppm? Or is there a salt level where conduction stops and there is a dramatic drop in the chlorine production, such that my salt may still be quite high, such as 2000ppm. We do not have a test kit for salt and don't have a shop within reasonable distance to take the water to for testing because we are in remote Australia. I can test for free chlorine, ph, akalinity. Is there any easy way to get figure out a salt level?--Dacium 22:27, 3 December 2007 (UTC)

is 3000ppm equivalent to 3 grams of salt per liter? If so and if you have the patience, you may be able to boil a liter of water and and then weigh the salt. This may require several steps of boiling in progressively smaller containers and carefully washing down the container walls with pure water to recover any salt that dries onto the walls. presumably you can zero out the empty weight of the final small container, so you need not actually scrape all the salt out of that last container. -Arch dude 00:39, 4 December 2007 (UTC)

I'm not much of an expert on this subject, but it seems to me like the chlorination cell is going bad. A pool will generally not decrease in salinity unless you are continually pumping in fresh water. In fact, salinity should go up due to evaporation. The chlorination cell (as I understand it from your question) will produce chlorine from the dissolved chloride ions in your pool, but the counterions (likely Na+) should remain. This would mean that you might see the pH of the water go up over time, which is arguably of greater immediate concern. 142.103.207.10 02:16, 4 December 2007 (UTC)

I am pretty sure then it is a problem with the cell like you said, particularly a bad wire that might not be making any contact. I can't figure out anyway how salt would disappear otherwise. The pool has been filled about 5 to 10% with rain water, but not enough that the salt level should be any less than 3,000ppm. I know it was 3,500ppm almost constantly for over a year without having to add any salt, and like you said the only problem I have ever had is the ph slowly goes up and I just add a little acid every weekend. It must be a dirty or dead cell.--Dacium 03:51, 4 December 2007 (UTC)

Well, if any water splashes or drains out of the pool that is not recirculated back in, and is replaced with fresh water, then you could lose salt that way. -- HiEv 04:36, 4 December 2007 (UTC)

The chlorine level however is a more than jsut a function of the generator and salinity. Temperature, sunlight and other chemicals are more likely culprits. Doesn't your chlorine generator tell you the current that is going through the cell? That is probably a good gauge of whether the salinity is correct. Also the generator may need to be cleaned. --DHeyward 07:26, 4 December 2007 (UTC)

Junk DNA

Seeing as most everybody's DNA (regular genes) are so similar is it the differences in our junk DNA which control when things get turned on (I can't remember the ACTG code for the on and off) and how much to be allowed, for instance how much height one person would grow how much to use of this gene or that gen to determine eye color? So would we basically all have the same genes/cells it is just the amount of the genes used that causes our variatioons. —Preceding unsigned comment added by 67.127.165.154 (talk) 22:33, 3 December 2007 (UTC)

Short answer is no. Quantitative traits are due to the different alleles for the various genes in a population. A small base subsitution may have a large difference in phenotype if it is a missense or nonesense mutation. Mutations in the regulatory sequences out side coding DNA can also have phenotype consequences (change gene expression) but these would never be regard as junk DNA. David D. (Talk) 22:46, 3 December 2007 (UTC)

To add to the above, the short answer is still no. However, there's still a lot we don't know about how genes are regulated. While known regulatory sequences wouldn't be considered "Junk DNA," that's not to say that we may find in the future that something we believed to be junk turns out to be important. I wouldn't be surprised if we learned one day that some of this "junk DNA" actually did play some role. What kind of role and how important it is remains to be seen. 142.103.207.10 02:06, 4 December 2007 (UTC)

I agree that some of the current junk DNA may well have important roles in regulation and potentially have non coding transcripts. When/If such discoveries are made will those specific sequences still be termed junk? I doubt it, so in a way the junk will always have no function, but we may see less junk in the future. David D. (Talk) 03:34, 4 December 2007 (UTC)

FYI, some noncoding/junk DNA is already known to have a purpose, like introns, for example. -- HiEv 04:48, 4 December 2007 (UTC)

It depends, many model organisms have quite small genomes, with equally small introns, are they classified as junk in those? Certainly there are some very large introns in humans so I could see some maybe most of those sequences, especially the repeats, being classified as junk, but it was known there were many regulatory sequences within the introns not to mention the sequences necessary for splicing. In general, I would not classify all intron sequences as junk and those who defined the term were specific in saying "without a function" because they were very aware that some of the intron sequences (and those between genes) were functional. So I'm not sure it is valid to consider introns enmasse as an example of junk DNA with a function. David D. (Talk) 04:54, 4 December 2007 (UTC)

Well, it kind of depends on your definition of "junk DNA". It was commonly believed that all noncoding DNA was unused at one point, thus was called "junk DNA". However, introns and other discoveries led them to discover that some of that "junk DNA" actually had functions, and other hypotheses have been made suggesting more possible uses for it. This is why many people are shifting to the term "noncoding DNA" instead, because calling it "junk" includes an inbuilt assumption of uselessness that isn't always correct. So, introns were considered "junk DNA" before people discovered that they had a purpose, and if you take a look at the junk DNA article you'll see that most sequences within introns are still considered "junk". -- HiEv 16:04, 5 December 2007 (UTC)

After go through the Wikipedia articles it sounded like the phenotype (aside from environment) were based on the genes or position on the chromosomes. If that is the case is the same gene like the one for hair and hair color in a different location for each person, won't be found in the same spot? AND is the on and off genes the same or in the junk genes cateogry?

No gene, even when "off", is in the junk category. On or off is related to development while some genes have no function in some cells all genes have a function in some cells of an organism. Junk is defined as having no function at all. Genes are in the same spot, but there are many flavors (alleles) of the same gene. The diferences you see are to the various flavours. David D. (Talk) 16:07, 4 December 2007 (UTC)

Proper interval locality theory

Yo, physicisterns, I stumbled across this (rather hastily thrown-together) site in the innertubules: [3]. After a precursory, half a cursory and three fifths of a postcursory examination, it seems like the guy is on to some pretty deep stuffs. Does anyone know:

• (1) if this is an entirely novel perspective on the various problems he purports to solve or demystify (entanglement, quantum gravity, etc.), and
• (2) if there might be any problems with the approach (of defining locality by null intervals in minkowski spacetime)

Your assistance is my subsistence, Rupert Barnswobble Sardinian, esq. 217.43.117.20 23:55, 3 December 2007 (UTC)

At a glance, it looks exactly like an introduction to quantum electrodynamics. I think that's the intention. It's certainly nothing new: electromagnetism and quantum mechanics have been jointly described since the 30s. Nothing of consequence is said about gravity, and QFT cannot support gravity anyway for fundamental reasons. SamuelRiv 00:32, 4 December 2007 (UTC)

I don't remember anything about minkowski spacetimes in Feynman's book on QED... Are you sure you didn't glance too glancingly? 217.43.117.20 01:46, 4 December 2007 (UTC)

Minkowski space is just flat space (equivalent to the Lorentz space of Maxwell's equations). They don't seem to change the curvature. Therefore there is no gravity (hence talking about special relativity instead of general relativity). SamuelRiv 08:29, 4 December 2007 (UTC)

According to proper interval locality the propagation of electromagnetism is facilitated by the signature of the space-time metric. Since the metric signature is common to both flat and curved space-time then the theory is valid in space-time as defined by both special and general relativity. I would suggest a glance is inadequate if you wish to understand proper interval locality, however here are some of the salient points.

1. The wave particle duality of matter results from the geometry associated with our inertial reference frames and is an inevitable consequence of the constancy of the speed of light relative to those frames.

2. The theory distinguishes between observable events that can be assigned precise and accurate locality relative to our inertial reference grids and quantum events that do not have exact locality relative to our inertial grids. (Where a quantum event is considered to be a point in the history of a quantum object relative to itself).

3. The metric associated with our inertial reference grids, precludes the possibility of quantum events being assigned a unique set of coordinates relative to our reference grids, instead quantum events are projected onto our reference as event surfaces.

4. The light cones illustrated in the website are quantum event surfaces. In free space the apex of the light cone is the proper interval locality of the quantum event.

5. Pairs of quantum objects are likely to interact if the apexes of their light cones are spatially close. (The likelihood of interaction falling off with the inverse of the square of the spatial separation)

6. Every point on the primary light cone is projected onto our reference grids as a secondary light cone. This mechanism results in an infinite succession of event surface projections that fill the whole of space-time. (It is this secondary quantum event surface projection that is responsible for the interference effects in experiments such a Young's double slit.)

7. In Aspect's experiment the quantum event surface associated with the cascade of the calcium atom intercepts the detectors at the moments the detections occur. The calcium atom relative to itself interacts with both detectors immediately and simultaneously, therefore, the result must be inherently correlated regardless of when the polarizers are set.

8. Proper interval locality is a self-consistent theory which is also wholly consistent with both relativity and quantum mechanics (That is the mathematics of quantum mechanics, clearly it deviates metaphysically in that it does not accept that light is required to be mediated by a particle.)User talk:WROBO 1 July 2008