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December 31

Light illumination?

Why does red light produce less illumination than blue or green light? NealCruco (talk) 01:01, 31 December 2012 (UTC)[reply]

Wikipedia doesn't have a good non-technical article on it (the closest I could find was Luminosity function), but the human eye is most sensitive to green light, and more sensitive to red light than to blue light, but more sensitive to variations in blue than in red, giving the appearance of greater sensitivity to blue. --Carnildo (talk) 01:34, 31 December 2012 (UTC)[reply]

The technical term (and the main article) is photometry, the field of study that deals with human perception of photons and illumination. Strictly speaking, a red light source and a blue light source and a white light source can all shine with the same luminous intensity, and yet still be perceived at different apparent brightnesses when viewed by the human eyeball (and the brain, which is usually attached, that processes the vision stimuli). This is because your eyeball is not the standard eyeball that was used to define luminous intensity. And of course, if you read and understand luminous intensity, it will be obvious why a blue, red, and white light-source might produce the same number of watts of visible light, yet vary significantly in perceived brightness: because brightness is perceived in a wavelength-dependent way by the human visual system. Everything from the photochemical response of retina cells, to the brain's psychological interpretation of color signal, is wavelength-dependent, and this ensemble must be approximated by one of the many common luminosity functions, or by one you create for yourself for your own purposes. Our photometry article elaborates on the subtleties of measuring "brightness" and related quantities; depending on your application, you may want to measure incident energy, or incident photon-count, or perceived luminous intensity, or some other specific quality/quantity. Many standard units and methodologies exist that cover most common use-cases. Compare radiometry, which avoids the messy bits of perception and instead deals exclusively with physical quantities like number od total incident photons, or watts. Nimur (talk) 04:11, 31 December 2012 (UTC)[reply]

Also, Purkinje effect may be relevant. Gzuckier (talk) 04:55, 31 December 2012 (UTC)[reply]

And any number of other contextual effects applied by various other modules in the visual system, as in edge and shape detection. Here are some optical illusions illustrating just a few of these forms of post-optic nerve processing of the raw luminosity/wavelength information provided by the eye: 1, 2, 3, 4, 5. Snow (talk) 06:30, 31 December 2012 (UTC)[reply]

Eating meat from a venom-killed animal

Would it be safe to eat the meat of a creature that has been killed by the venom of another animal, say a chicken bitten by a rattlesnake or a fish stung to death by jellyfish? Or would that depend on the individual animals involved? 69.111.189.155 (talk) 02:06, 31 December 2012 (UTC)[reply]

We can't answer medical questions here. Hot Stop (Talk) 02:10, 31 December 2012 (UTC)[reply]

We can't give medical advice, but hopefully no one is being advised here. Our article venomous snake says something I didn't know: "It is, for example, harmless to drink snake venom as long as there are no lacerations inside the mouth or digestive tract. The two exceptions are: the Rhabdophis keelback snakes secrete poison from glands they get from the poisonous toads they consume, and similarly, certain garter snakes from Oregon retain toxins in their livers from the newts they eat." In general, every toxin is different, so it is impossible to make any general statement with accuracy - I don't know if those are the only two exceptions. Wnt (talk) 02:19, 31 December 2012 (UTC)[reply]

Just to clarify, I didn't intend for this to be medical advice. I was just curious. Thanks for the responses anyway! 69.111.189.155 (talk) 03:50, 31 December 2012 (UTC)[reply]

Our article snakebite points to a paper "Riggs BS, Smilkstein MJ, Kulig KW, et al. Rattlesnake envenomation with massive oropharyngeal edema following incision and suction (Abstract). Presented at the AACT/AAPCC/ABMT/CAPCC Annual Scientific Meeting, Vancouver, Canada, September 27 October 2, 1987." which (the article claims) indicates that people have gotten poisoned by sucking snake venom from other people's wounds...so I suppose it's not impossible for you to get into trouble by eating venom-killed meat. But the size of the dose from eating a pound or so of the meat from an animal seems like it would be rather small in a 100lb+ human provided you didn't eat the part of the animal close to the actual bite site. Tough question though...I wouldn't want to bet my life on anyone's answer here! SteveBaker (talk) 05:01, 31 December 2012 (UTC)[reply]

I tracked that abstract down a bit further out of curiosity: "Riggs et al (1987) reported the case of a 29 year old man with no prior history of snakebite, who was bitten on the left index finger by a rattlesnake. The patient had performed incision and oral suction before seeking medical attention. He also had recent dental surgery and gingival irritation and mucosal breaks. Mild edema from the bite site to the wrist and a mild coagulopathy developed. The most striking feature was massive oropharyngeal edema with dyspnea, wheezing, and inability to speak, which occurred before any antivenin was administered. The massive oropharyngeal swelling may have been due to absorption of venom through the injured gingival mucosa and brings the safety of incision and oral suction into question." (found at [1]) I note that this was the same patient who had otherwise been bitten, which means there could be some pattern of interaction between the suctioned venom and the injected venom components, so I don't know for sure this extends to any random sucker. Wnt (talk) 18:46, 31 December 2012 (UTC)[reply]

Notice that people have been using arrow poison for thousands of years. Icek (talk) 23:15, 31 December 2012 (UTC)[reply]

Very many natural venoms are complex molecules with high molecular weight. These usually break down into harmless compounds both under the influence of heat and by contact with stomach acid. As always, there are exceptions (as e.g. if the venom enters the bloodstream via a would in the oral cavity), so caveat emptor. --Stephan Schulz (talk) 12:01, 2 January 2013 (UTC)[reply]

Even simple toothbrushing leads to considerable bacteremia -- you must consider that oral mucosa is quite thin and the lamina propria containing the most superficial vasculature is so close to the surface that it's, in essence, what gives the oral mucosa its red coloration. As such, it's possible for venom to enter the bloodstream by coming into contact with alimentary canal mucosa when there is even the slightest abrasion, such as cheek biting, piercings, burns, ulcerations, etc. But envenomated organisms being used as food would have likely distributed the venom to some degree before their demise, and then it's a matter of pharmacological understanding of things like volume of distribution, etc., perhaps. DRosenbach ^{(Talk | Contribs)} 18:12, 3 January 2013 (UTC)[reply]

How can i Make a Ligand substance be SELECTIVE on specific receptor areas ?

Let's say i create a new general material which inhibits all types of Gaba receptors, but i want it to be selective to a very particular area of the brain. in other words, while the substance can influence all brain areas with Gaba R, I want it to focus on a particular one.

what are the princilpals of making a particular molecule Selective? what things should i take for granted? when constructing this molecule.

THIS IS NOT HOMEWORK !, i ask because i want to know about the principles. i understand that lately, some new info was discovered about this. thanks. 109.65.115.101 (talk) 06:20, 31 December 2012 (UTC)[reply]

Well, I suppose you could make something which reacts more with grey matter or white matter, or perhaps with areas that are more active (use more glucose), but I don't know how you could make it only react with, say, areas storing memories of cats. There has been some study on applying electromagnetic fields to the brain, and perhaps you could make something that would only be activated in the presence of a strong electromagnetic field, and thus you could control which regions of the brain are affected, by altering the field strength and shape around the head. StuRat (talk) 07:10, 31 December 2012 (UTC)[reply]

if i understand you correctly what you say is: after a ligand is given, we could "Navigate it" to a specific brain regions by external methods? — Preceding unsigned comment added by 109.67.131.95 (talk) 09:57, 31 December 2012 (UTC)[reply]

Either that, or activate it in a particular region, so it would float inertly through the rest of the brain. StuRat (talk) 03:44, 1 January 2013 (UTC)[reply]

With regards to GABA receptors, which are located on the cell membrane, there is no (current) way of making a non-selective ligand selective for a brain region. If it can pass the blood-brain barrier, then it will diffuse amongst the entire brain. There are ways of making a drug selective to a brain region if that region expresses selectively expresses something. For example 6-hydroxydopamine given systemically will selectively kill midbrain dopaminergic neurons and noradrenergic neurons, because it is taken up by the dopamine transporter and noradrenaline transporter, so only neurons expressing these transporters will uptake it. With regards to GABA ligands, there are different expressions of GABA receptor subunits in different brain regions, so one can design a ligand which will only bind to GABA receptors which contain a specific subunit (but this ligand will still diffuse amongst the entire brain). There's currently a large amount of research going into this in the hope of developing anxiolytics without amnesic effects, etc. --Markr4 (talk) 11:03, 31 December 2012 (UTC)[reply]

Hey Mark, and many many thanks for kindness. about the anciolytics you mentioned. are all amnesic?, and, does this amnesia caused by Necrosis?

thanks ! — Preceding unsigned comment added by 109.67.131.95 (talk) 12:58, 31 December 2012 (UTC)[reply]

Well the anxiolytics I was referring to were benzodiazepines, each which have their own unique attributes (i.e. some are more amnesic than others, probably due to GABA receptor subunit specificity). But benzodiazepine-induced amnesia is almost certainly not caused by necrosis.. Rather it is caused by their enhancement of GABA-mediated inhibition of long-term potentiation, probably in the hippocampus. Here is a link to a free-to-read paper which talks about the role of the GABA-A alpha-4 subunit in amnesia (although they used isoflurane for proof of concept). Here is a link to a review paper discussing the role of all the GABA-A receptor subunits. --Markr4 (talk) 19:34, 31 December 2012 (UTC)[reply]

Look up "the GABA receptor" and you will see that in fact, there are many different kinds of GABA receptors. Because there are different kinds, it is possible to have many different kinds of GABA agonists which affect different channels and have different effects. Ethanol, GHB, barbiturates and Quaaludes are not precisely the same, for example. The same is true for most other receptors - for example, you can design cannabinoid drugs to do anything from suppressing appetite to treating inflammatory bowel disease. Wnt (talk) 15:01, 31 December 2012 (UTC)[reply]

To start to answer your question (to control where the drug is activated independently of structure) see [2] for an idea and [3] for some results (though I think that example is far too crude to possibly work for your application, and it may not even count as a proof of concept). Wnt (talk) 15:11, 31 December 2012 (UTC)[reply]

Making drugs that are more selective is the dream of pharmacology. Currently the only way of doing it is to try making small changes in the structure of a molecule and hope you get lucky. Lots of people have been trying to develop a principled approach to the problem, but so far it hasn't panned out very well. Looie496 (talk) 15:27, 31 December 2012 (UTC)[reply]

OK, so this is not really an answer to the question, but this could be done in an experimental setting with transgenic animals. As long as you have a protein-based inhibitor that could be expressed in mammalian cells (not sure if one exists off the top of my head), use of a region or cell-type specific promoter will allow you to do this. Slight off-topic, I admit. Fgf10 (talk) 17:13, 31 December 2012 (UTC)[reply]

Not at all off-topic. Gene therapy may have hit some snags in initial trials, but there is no reason to think it will not one day be as simple to use as a chemical pill is today, and as you say, it could be exquisitely fine-tuned. Wnt (talk) 18:39, 31 December 2012 (UTC)[reply]

I didn't even think of the gene-therapy angle, but that's a good call. (I spend a big chunk of my professional life working with transgenic animals, so it's always my first thought). There have been efforts to use specific promoters to enhance gene therapy already. Fgf10 (talk) 19:05, 31 December 2012 (UTC)[reply]

Probably it is possible to archive using optical control of protein activities (Google: controlling protein activities with light). And then use technics from optogenetics to activate protein only in selected regions of the brain. Currently most research are done around intracellular activities of proteins, but technically it should be possible to create one that would bind membrane receptor only in a presence of light. TMMForever (talk) 19:34, 31 December 2012 (UTC)[reply]

Specific capacity... What the heck is it?

Here is the quote:

The anode shows also superior stability over 600 cycles and exhibits high specific energy (200 Wh/kg) delivered at a specific power of 30 kW/kg. The TiO2 anode in a full Li-ion cell with a LiNi0.5Mn1.5O4 cathode operates at 2.8 V and demonstrates the highest (310 mA h/g) reversible specific capacity reported to date.

http://pubs.acs.org/doi/abs/10.1021/nn900150y?journalCode=ancac3&quickLinkVolume=3&quickLinkPage=907&volume=3

I could understand "specific energy" and "specific power". Both numbers(200 Wh/kg & 30 kW/kg) do make sense. But "specific capacity"? Look, 310 mA h/g at 2.8v, if we convert to wh/kg, that would be 868 Wh/kg. And we are talking about QUOTE:"full Li-ion cell". But they just claimed anode got specific energy of 200 Wh/kg. So only way to wrap my head around is to assume that cathode have way higher specific energy then 868 Wh/kg achieved for full cell. Which is not realistic.

Or may be "specific capacity" means something very different then "specific energy"? TMMForever (talk) 11:45, 31 December 2012 (UTC)[reply]

The given units mA h/g would seem to have the dimensions of charge/mass, which I suppose might be called specific charge. My guess therefore (and it is a guess) was that the sentence was intended to read specific charge capacity. --ColinFine (talk)

Yeah by itself 310 mA h/g have detentions of current*time/mass, but if we take into account mentioned 2.8 V we actually should get specific energy. IMHO. Please also take a look at the link to abstract, they have a nice graph that try to explain characteristics of the cells in question, with one axis representing "specific capacity". But I admit, I actually clueless as to what specific charge capacity represents... TMMForever (talk) 12:26, 31 December 2012 (UTC)[reply]

Here is an explanation of what that represents [4]. Mikenorton (talk) 12:38, 31 December 2012 (UTC)[reply]

Perfect, thank you! TMMForever (talk) 18:23, 31 December 2012 (UTC)[reply]

And still talking about specific (charge) capacity, to understand the beast, could someone estimate specific energy of the cell in question? Provided the above mentioned sentence("The TiO2 anode in a full Li-ion cell with a LiNi0.5Mn1.5O4 cathode operates at 2.8 V and demonstrates the highest (310 mA h/g) reversible specific capacity reported to date.") and this graph: http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jpccck/2012/jpccck.2012.116.issue-4/jp210793u/production/images/medium/jp-2011-10793u_0006.gif

Should I just use 2.8V mentioned in sentence to calculate specific energy? Or should I take discharge voltage from the graph, looks like 1.4V at 310 mA h/g and use that to estimate Wh/kg? Or some other strategy? TMMForever (talk) 18:23, 31 December 2012 (UTC)[reply]

Scientific explanation for ESP (Extrasensory perception)

I have since I was a child been having experiences which would be called ESP (Extrasensory perception), even recently I have had some experiences that I cannot explain such as I had had a horrible feeling that if I went out that day something bad was going to happen to me, well I had to go out, and when I was reversing in my driveway My mirror hit a garbage can that someone had put in my path and the mirror exploded showering glass all over me and the inside of my car through my open window. I also predicted Michael Jackson's death three months before it happened, I just had this strong feeling that he was going to die soon and he did. The same thing happened to my dog. Although she was 12, she was in reasonably good health. I had this strong feeling that she was going to die soon and she died a week later. I am atheist and I don't believe in a afterlife or spirit world so I have no real way to reconcile these experiences with science, which is what I believe in. Has science ever been able to explain things like ESP.--Jason677 (talk) 14:53, 31 December 2012 (UTC)[reply]

This could be confirmation bias - how many times have you had these feelings but it did not turn out to be a correct prediction so you have forgotten about it?--Gilderien Chat|List of good deeds 15:22, 31 December 2012 (UTC)[reply]

(ec)What you describe is not actually ESP but precognition. Most people here will tell you it is bunk, confirmation bias in your recall of events. If you don't believe that, you may believe that it is very dangerous, and has been warned against by several religions. I hesitate to explain further, because the more one understands it the more dangerous it is... Note that our article on the Diocletian persecution reports that it started when some believers making the sign of the cross were able to block the perceptions of the Emperor's haruspices, which suggests a remedy. Wnt (talk) 15:31, 31 December 2012 (UTC)[reply]

Perhaps the postulated parent universe's virtual machine(s) are getting hacked. ;) --Modocc (talk) 17:05, 31 December 2012 (UTC)[reply]

It could have been a self fullfilling prophesy too. If he/she was spending too much time worrying about unknown dangers his/her attention to hazards in his/her immediate path could well have been compromised. Wickwack 124.178.61.38 (talk) 16:07, 31 December 2012 (UTC)[reply]

WHAAOE! We have an article on Self-fulfilling prophecy too... How about that for foresight! -Modocc (talk) 16:28, 31 December 2012 (UTC)[reply]

Here is a excerpt from Richard Feynman's book, Surely you're joking, Mr. Feynman:

"I remembered the time I was in my fraternity house at MIT when the idea came into my head completely out of the blue that my grandmother was dead. Right after that there was a telephone call, just like that. It was for Pete Bernays--my grandmother wasn't dead. So I remembered that, in case somebody told me a story that ended the other way."

I have my own story. When I was young (aka a few years ago), I went on a class field trip to Paris. At the base of the Eiffel Tower, I had a strong feeling that something terrible was going to happen if I went up the tower. I had to go up, and it remains one of the most enjoyable and memorable experiences of my life.

I propose an experiment. Every time you predict something, or have a feeling something's about to happen, you write it down in a notebook within 24 hours. Every prediction must have a timeframe--you can't just say "Barack Obama will die" or "something bad will happen to me", because both of those are certain to come true at some time. If you forget to write it down in 24 hours, or if the event happens before you get a chance to write it down, don't write it down (it doesn't count). After a predetermined amount of time, say half a year, you look at the notebook and count up the events that did happen and the events that did not. For this to work, you have to be very disciplined in using the notebook. Under no circumstances can you revise previous entries, excuse yourself for missing the prediction timeframe, excuse inconsistencies between your prediction and what actually happened, add in entries after 24 hours have passed, or start counting up entries before the pre-determined amount of time has passed. I suspect that if you conduct this experiment, you'll find very few correct predictions amongst a vast number of completely incorrect ones. --99.227.0.168 (talk) 17:14, 31 December 2012 (UTC)[reply]

That would be a way for the OP to reconcile fact from fiction, especially if the OP is prone to making predictions. Some people obviously are and have faulty memories of them, but not everyone. Since I'm uncertain about most future events my notebook would be fairly void. -Modocc (talk) 18:27, 31 December 2012 (UTC)[reply]

I think the notebook experiment is an excellent idea. It requires extreme honesty and self-monitoring though...perhaps it would be better to have a close friend fill out the book on your behalf and verify which predictions come true. Here are some ways in which you can be deluded into thinking that you can predict the future:

You may make many predictions - and statistically, those are a small enough percentage to be accounted for by chance. You mentally bury the failed predictions and vastly inflate the successful ones.
You may make a prediction - and because of that prediction, subconsciously cause something to happen to match your prediction.
You may see an event and have a confabulation (a false memory) that you had predicted it.
You may make predictions that are sufficiently vague (eg "something bad will happen to me today") that you are almost certain to be able to find a match.
You may have some knowledge that enables you to make a prediction of something that's very likely to happen.

The notebook approach will reveal #1 and #3 - but #2, #4 and #5 are harder to pin down. SteveBaker (talk) 18:59, 31 December 2012 (UTC)[reply]

A very close friend of mine has had several seemingly inexplicable vivid and difficult to explain detailed precognitions, but the only vision I've ever had, that I'm aware of, happened when I unexpectedly felt a sudden awful emotion, a mix of hopelessness, dread and sadness; a deep sinking and sickening feeling that I had never experienced before or since which caused me to lay down, at which point I lapsed into a semiconscious dream in which I sensed everything spinning in addition to an image of what appeared to be luggage in a small space and a very dark landscape of water rushing around. This was a very brief vision, a few seconds at most and it happened just before sunset on the day John F. Kennedy, Jr. plane crashed. Just a coincidence I'm sure (see our article [5] on interpreting coincidences), mainly because with some eight billion plus people on this planet various unusual coincidences will occur and we tend to publicize them when these happen and thus these seem salient... but if what happened to me was of something that runs much deeper, like some sort of block time phenomena, science nor any garden tramping mutt has yet to pull back the curtain. -Modocc (talk) 19:50, 31 December 2012 (UTC)[reply]

If you get a chance, read in Johnny Cash's autobiography, about a day when everyone in the family had a sense of forboding about the day, including his brother, who nonetheless went to his job at the sawmill, and suffered a fatal injury. This kind of thing may indeed be all confirmation bias or some kind of natural intuition or just coincidence, but it's still possible there's something there. I call it "bad vibes". ←Baseball Bugs ^{What's up, Doc?} carrots→ 06:37, 2 January 2013 (UTC)[reply]

So is there a scientific explanation for "bad vibes" ?--Jonharley667 (talk) 18:14, 2 January 2013 (UTC)[reply]

The problem is that these are all anecdotes - there isn't enough hard data here to do any kind of an investigation.

In the Johnny Cash example, how do we know that this general sense of "foreboding" wasn't distracting to Cash's brother and the cause of his fatal sawmill accident? Once you exchange cause and effect, you can remove the accident from the story and you're left with "Why did everyone have a strong sense of foreboding on the same day?" - for which it's easy to come up with answers. Maybe nobody slept well because of some common cause, maybe depression and anxiety in one or two members of the family caused everyone to feel weird? Then there is the problem that if several members of the family professed foreboding after they heard of the accident, in all likelyhood all of the other members would say the same thing just to avoid being the only person who was not seemingly prescient. We'd also need to ask whether the family frequently felt things like that...perhaps this was the 50th time that year that many of them felt "foreboding" and the accident was a mere coincidence? Finally, we don't know for sure that the story is even true. When writing an autobiography, it's very hard to find enough interest in an early, mostly humdrum life to fill out all of those chapters...so events get exaggerated, embellished or perhaps even completely fictionalized.

You can't base science on that kind of flaky evidence. If "bad vibes" is truly "precognition" - then more or less the whole of science must be entirely wrong...and it plainly isn't that badly incorrect because if it was, those errors would be highly noticeable in other ways. I bet that if there was some physics-related way in which people could "feel" the effects if future events, then that effect would be felt in many other ways - which would likely result in all of the results of science coming out quite differently.

There is also a paradox going on here. Suppose everyone learns from the Cash autobiography and henceforth, everyone who feels "foreboding" decides to stay at home that day instead of going to work? Then sawmill accidents wouldn't happen - so the foreboding feeling (as a prediction of the future) couldn't be there. So they wouldn't stay home - so the accident would happen - so they'd feel foreboding...it's a paradox that can only be resolved by assuming that it's all bullshit...which, of course, it is.

Occam's razor tells us to look for simpler explanations - until and unless something compelling is discovered.

If people wrote down and widely published their precognitions before the event they are predicting - and if they also accurately quantified the number and severity of bad things that happened to other people without reading about their precognitions - then we could do a statistical correlation study and perhaps we'd have something to work on. Which is why the idea of having our OP fill out a journal is such a good one. It will reveal much about what's happening here. SteveBaker (talk) 14:40, 3 January 2013 (UTC)[reply]

The paradox is resolved only by assuming it's all BS? That is not the only possible resolution though, because the paradox is a straw man. Assuming a precognition is that of a real future event, lets say a really bad one such as the end of the world (and not merely a possible imagined event), then the future event occurs and the person did not prevent it. There is no contradiction in that. Of course, easily fabricated fortunetelling is generally bunk, because otherwise the lotteries and casinos would have to shutdown. Modocc (talk) 17:36, 3 January 2013 (UTC)[reply]

So to put this in strictly physics terms - you're saying that the transmission of information backwards through time is possible if there is no way for the arrival of that information to change that future event to the degree that make the information invalid (and thereby cause a paradox)? You might conceivably be right about that - but it's really not the case in the Cash autobiography anecdote where that reverse information flow could easily have changed the validity of the information and resulted in a paradox.

However, when you start thinking of it like that, you have to ask: How does the reverse information flow from a tragic death "know" which brain cells in which humans to influence? How does the universe classify events (such as a tragic death) to be sent back as a precognition rather than some other irrelevant event such as a tree falling in a nearby forest? If all information is sent back to influence all humans - then it would produce profound and measurable change in the moods of everyone. But how does a purely physical world "know" to influence only those brains that care about the result? Why does the result of certain atoms changing position in Johnny Cash's brother's body in a sawmill convey information into those specific people's minds where the wreck of a total stranger's car and death of half a dozen people have no effect on those very same brains? For the universe to work like this, there would have to be causal links between specific groups of atoms in people's brains and other groups in related people's bodies - but how those are correlated would have to be tied fundamentally to things like human cultural norms. How does precognition "know" that death is important and eating lunch isn't?

Furthermore, it took a significant amount of energy (presumably somehow propagating back from the future) to flip the mental states of those people - unless this reverse information flow somehow "cares" about what facts are sent back and to whom, the total amount of energy radiating from the future would be clearly measurable on a macroscopic scale. Why don't we see serious errors in energy balance equations of all kinds due to this flood of reverse-time information/energy flow?

You can bundle precognition with religion and imagine some intelligent and omniscient agent who decides what events have to be precognate to which people - but you can't find a way to finagle this into "science"...which is what this Reference Desk is here to discuss. Then you have to ask yourself "What is the motive of this godlike intelligence in giving people vague and useless information from the future?"

Precognition just doesn't stand up to careful thought.

SteveBaker (talk) 20:27, 3 January 2013 (UTC)[reply]

The paradox is very much self-negating (self-regulating perhaps) though, because if there is an actual paradox then the precognition obviously would not occur. Therefore regardless of the reasons for the Cash family's precognitions the existence of such paradoxes was irrelevant. Even with precognitions, or in spite of them, for whatever their causes are, us creatures do suffer in the jaws of reality anyway. Certainly we need not tolerate gatekeepers regulating our concerns at all, for we actually do naturally regulate our own interests with whatever spirit is physically embodied by our roots and future prospects which happen to give us our different abilities which aid or hinder us when circumstances warrant. What these attributes of mind, body and environment entail is not fully understood and there are numerous avenues we have not yet explored. As for reversible information flow with block time, standing waves typically do not have very large net velocities and information regulated by the brain does not need to entail huge amounts of energy either because of its ability to trigger independent slave processes (why one can automatically tie their shoes without relearning how to do it each time). As for this being a science board, its not enough to throw up barriers against straw man models anyway, for reality is whatever it is. --Modocc (talk) 01:06, 4 January 2013 (UTC)[reply]

Perhaps the information flows backward the same way as forward, in the hippocampus, and is selected by similar means; occasionally it may be unclear whether past or future events are being remembered. Note that the model I suggest is quite strictly one of sensory, not extrasensory perception, though of course watching a news broadcast counts. Wnt (talk) 03:22, 4 January 2013 (UTC)[reply]

True, and that may explain a good number of cases in which coincidences get mistakenly embellished. But that cannot completely explain my particular vision because when I had my horrific dream I discussed it with my friend who was visiting me at the time because I was greatly disturbed by it; much more so than the news which I heard about the next day (as horrible as that was). An odd coincidence of events of course, and as with other paranormal superstitions, extrasensory perceptions are debunked for most, if not all, common situations, but I've always been amazed by how nature has sometimes evolved fairly rare abilities that fit rare niches though; thus I won't rule out a more interesting physics which we share any more than I would a parent universe emulating us with godlike powers. --Modocc (talk) 04:12, 4 January 2013 (UTC)[reply]

What accounts for the heavy taste of Beer?

I always assumed there was starch in beer, hence light beer without the starch. Turns out that's way off. So what exactly does make beer taste heavy compared to wine and liquor? μηδείς (talk) 22:49, 31 December 2012 (UTC)[reply]

Surely that depends entirely on the kind of beer? Weak American lagers are way lighter than wine, but a good decent English ale can be quite heavy. Don't think there's a single answer to it. However, there is a lot of sugars and complex carbohydrates in most beers compared to wines and spirits, so that probably accounts for a lot of the 'heavy' taste. Fgf10 (talk) 23:01, 31 December 2012 (UTC)[reply]

1. What is a "heavy taste"?

2. Is it universal, in every beer in every country?

3. In my country, Australia, "light" beer means lower alcohol. I get the impression the OP is talking about lower kilojoules (or calories). Can this be clarified please? HiLo48 (talk) 23:19, 31 December 2012 (UTC)[reply]

I'm enjoying Bavaria 8.6 right now. It is definitely got a heavy taste! Although North American flavor have only 7.9% alc./vol. So I would agree, heavy would mean higher alcohol content. But there might be some other things that affect taste. Think of Guinness, dark varieties do taste heavier... Happy New Year! TMMForever (talk) 00:00, 1 January 2013 (UTC)[reply]

And btw, this Bavaria taste way heavier then 13% alc./vol. Merlot or other vines with high alc content... But sorry, not sure as to why. TMMForever (talk) 00:14, 1 January 2013 (UTC)[reply]

Beer has a 'body' to it that wine and liquors don't have, similar to the way milk and orange juice have a body but water and soda do not. Some beers have a stronger body than others--and while dark beers tend to have more 'body' I don't think it's due to the darkness itself. For example, DAB Alt, which is dark, has a very crisp, soda-like texture. I had always assumed this was due to dissolved sugar or fiber. But our beer article implies there is no fiber, and this website implies beer has no glycemic load. As for lite beer, I had always assumed that meant low in sugar, but our article says it is only lower in alcohol content--which is what got me wondering when I read it. I generally drink red wine or liquor, but over the holidays my family always has a lot of beer, and I like Guinness. Two bottles of that will fill me to the point of not wanting to eat, while two glasses of wine would never do that. Given I'm watching my blood sugar, I am wondering if beer is worse than liquor, but the website I linked to implies it is not. So I am left wondering what exactly it is that leads to the beer's 'body'. μηδείς (talk) 01:21, 1 January 2013 (UTC) PS, Yes, I have drunk beer in Germany, Switzerland and Austria, there is no difference--that is, beer of all sorts in all countries has this body and liquor doesn't. μηδείς (talk) 01:26, 1 January 2013 (UTC)[reply]

Protein apparently. From Mash ingredients: "Corn was originally introduced into the brewing of American lagers because of the high protein content of the six-row barley; adding corn, which is high in sugar but low in protein, helped thin out the body of the resulting beer. Increased amounts of corn use over time led to the development of the American pale lager style." -Modocc (talk) 03:28, 1 January 2013 (UTC)[reply]

Sounds like you're asking about the "mouthfeel" of a beer amongst other things. Beer is far more complicated to make than wine, which is basically grape juice and yeast: beer/lager is basically malted barley, yeast, hops and water (with some other stuff as adjuncts). The way the barley is roasted contributes a lot to the colour, taste and body of the beer: a very pale malt will produce a pale beer. Crystal malt is slightly caramelised and is used in most bitters and milds in the UK. Black malt is the darkest and is used in stouts and porters such as Guinness, looks and tastes burnt. And then there's the type of yeast and length of fermentation of the beer/lager. Not forgetting the nature of the water (liquor to brewers) - has it been Burtonised? Oh and what variety/varieties of hops are used? We have an article on Cask ale for your delectation. As for what you refer to as "liquor" (which sounds like what the UK calls "spirits), whiskey is basically distilled beer. --TammyMoet (talk) 10:33, 1 January 2013 (UTC)[reply]

Yes, by liquor I mean what them highfalutin' folks both here in the states and them in yonder strange jurisdictions calls spirits. μηδείς (talk) 21:37, 1 January 2013 (UTC)[reply]

Mouthfeel is a much more general term, but it would obviously include what I am talking about. Protein seems likely, given it is a significant if slight nutrient listed for beer. But what sort of protein then is clear and water/alcohol soluble? I am still not clarified. μηδείς (talk) 21:33, 1 January 2013 (UTC)[reply]

The definition of "light beer" is a matter of local law, and varies from country to country. In Canada, by law, a "light beer" is one that is low in alcohol. In the United States, a "light beer" is low in calories. There is some connection between the two, in that reducing alcohol content in beer also tends to decrease the caloric content. The reverse is not true, however: American manufacturers have developed ways of reducing caloric content in beer without a comparable reduction in alcohol. Some American light beers could not be labelled as light beers in Canada, and vice versa.--Srleffler (talk) 19:17, 3 January 2013 (UTC)[reply]