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CraigD

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  1. Like
    CraigD got a reaction from NoMoney in Could A Person Drown From Steam In A Shower?   
    “Could a person drown from steam in a shower?” is an interesting question.
     
    By the conventional medical definition of “drown”, the answer’s a clear NO. “Drowning” mean “respiratory impairment from being in or under a liquid”. The steamy air in a shower – a mixture of gasses, water vapor and droplets – isn’t a liquid, so can’t be the cause of drowning.
     
    If we broaden the definition of drowning to something like “respiratory impairment due to water in the lungs”, we can sketch some scenarios where a person might have respiratory distress, or even death, due to showering.
     
    I’ve noticed that I sometime cough when breathing deeply in steamy shower, which I guess is due to the water vapor and droplets tickling my trachea, triggering the cough reflex. The coughing prevents water from condensing and running down my airways into my lungs. It’s not normally harmful to get clean water in your lungs this way, because the lungs can absorb not only oxygen, but liquid water, so even without the coughing, even if I deep-breathing steam showered for hours, my lungs wouldn’t fill with water, drowning me.
     
    A person with an illness or disease that impaired the lungs’ ability to absorb water might not do so well.
     
    A person also might get much more water in their lungs in a shower by directly inhaling the water streaming from the shower head. This wouldn’t be pleasant or easy – in my experience from doing this accidentally, the cough reflex is so powerful it would be difficult to intentionally continue – but people can force themselves to override their reflexes to so some intensely weird things, so I wouldn’t say it’s impossible.
     

    The main reason most internet discussion of this have concluded it’s an urban myth is that the amount of liquid water in the volume of steam that a person can inhale in the typical duration of a shower is too low to fill the lungs. 
    At normal atmospheric pressure, steam has a maximum (saturated) density of about 0.590 kg/m3. An average person breaths at an average rate of about 0.00015 m3/s. Most lungs have a total volume of 0.004 to 0.006 m3. So a person inhaling fully saturated steam, who’s lungs are unable to absorb any water, would fully fill their lungs in about 15 hours. A steamy shower is less than fully steam saturated, so this time would be longer.
     
    A person who’s lungs can’t absorb water is likely to have a pulmonary edema, so their lungs would be filling with fluid whether they breath steam or not. Even when this happens, people reflexively cough, expelling the fluid.
     
    So the only scenario I think could lead to respiratory arrest due to breathing steam would require that they have pulmonary edema – perhaps by hyper-hydrating them with an IV line – and their cough reflex being suppressed – perhaps by anesthetizing them, or inducing a coma with drugs.
     
    A good thing to do with stories like this is to try to track down the source of the story. In some cases, it’s from speculation like I’ve made, which someone misreport as an actual medical case. Do you have a link to the place you heard this story, Lisa :QuestionM
     
    Sources: http://www.engineeringtoolbox.com/saturated-steam-properties-d_457.html, http://en.wikipedia.org/wiki/Respiratory_rate#Normal_range, http://en.wikipedia.org/wiki/Tidal_volume, http://en.wikipedia.org/wiki/Pulmonary_edema
  2. Like
    CraigD got a reaction from DynamytNinja in How Long Would Somebody Live If They Suddenly Became Allergic To H2O?   
    I read about a very rare (less than 50 documented cases since it was recognized as a distinct condition in 1963) condition known as aquagenic urticarial (hives). Though it’s not, in a technical, medical sense, an allergy – as I noted in my previous post, it’s likely not possible for the immune system to target water – it’s a condition where brief exposure to ordinary water causes a severe skin reaction. The best description I’ve read is about a UK woman named Michaela Dutton, who appears in several non-medical stories, such as this 2009 Daily Mail article.
     
    It’s not an ordinary allergy – that is, the immune system targeting water. Its cause is a medical mystery – the linked to NIH webpages suggest 2 possibilities:
    A substance dissolved in water enters the skin and triggers an immune response. In this theory, the hives are not caused by water, specifically, but rather an allergen in the water. An interaction between water and a substance found in or on the skin generates a toxic material, which leads to the development of hives.
  3. Like
    CraigD got a reaction from hazelm in When is art, not art?   
    Sure, I'll have a go at it. :D 
    I’ll beginning with the parable of the “Emperor’s New Cloths”.
     
    The object in question here is nothing, so fairly clearly can’t be defined as art per se. However, the act of convincing an emperor and all his subjects that nothing is actually something to the extent described in the story, is, I think, art, and the fictional protagonists (the two “tailors”) artists. There is actually a recognized term for this kind of artist: con artist.
    My first exposure to it, as I’m not into the English art scene, was just now, via its wikipedia article. (actually titled “My Bed”) 
    I like it, having on more than one occasion though my messy bed was rather a work of art, and recognizing that it tells a story to which lots of viewers can relate. It’s clearly in the genre of found art, which some are reluctant to “officially” accept as “art”. As I’m more-or-less in agreement with Goethe on the definition of art (that which “entertains, edifies, and exalts the human spirit”), I think found art is art. In its extreme, its art because it provokes an outraged “this is not art” from its viewer. This doesn’t preclude me disparaging the person who purchased the installation for £150,000, even if he subsequently resells it realizing a greater financial profit than I’ve ever dreamed of.
     
    Again, seeing it for the first time just now via this image (actually titled “Away from the Flock”). 
    I’m not crazy about Hirst’s studio’s (Hurst actually has never done much if any of the actual work on pieces ascribed to him, believing that the person who sets in motion the creation of piece, not the person who fabricates it, is the artist) work, However, I saw a similar work (perhaps one of Hirst’s, perhaps not – I can’t recall it’s placarding or find reference to it), a single preserved cow cut into about a dozen many lateral slices, sandwiched in glass, and spaced so you could walk between them, that moved me profoundly. I’d term this kind of art “nontraditional taxidermy”, but can’t deny its success as art in the senses Goethe described.
     
    It also, I think, influenced a scene I liked very much in the IMO underrated 2000 movie “The Cell”.
     
    It’s interesting, I think, that both of the pieces Paige mentions have provoked acts of vandalism that were themselves at least minorley artistic: a couple of performance artists having a pillow fight in Emin’s installation, titled “Two Naked Men Jump Into Tracey's Bed”; and someone pouring ink into the tank of “Away from the Flock”, retitling it “Black Sheep” (and getting in pretty serious legal trouble). Such wit, the British!
     
    I discovered in my recent skim of the subject that as of 1999, there’s an art movement, Stuckism (AKA remodernism) manifesting something close to Paige’s sentiments. For example, from their manifesto(s):

    "Artists who don't paint aren't artists."This reminds me of a less famous statement by a teacher of mine during my couple of semesters as a Fine Arts undergraduate:

    "Someone who paints as badly as you shouldn’t be an art major!"In my defense (and tooting my own horn) I could sculpt wax (for metal casting) better than anyone in the department, and as well as all but a handful of professionals I’ve known. ;) I did take his and others' advice, though and change my major.
     
    A final recommendation, this one apropos Jackson Pollock, an early modern artist who people commonly accused of not being a “real artist”: before coming to this conclusion, try actually making your own Pollock – it’s less easy than many think. :phones:
  4. Like
    CraigD got a reaction from JMJones0424 in If A Bomb Were Encased In Graphene, How Big Of A Blast Would It Be?   
    Not much would happen.  

    No and no. 
    Graphene is just carbon in the hexagonal crystal form found in graphite. It has about the same energy density as coal, so adding it to any other fuel, either a bomb or something that burns more slowly, would increase the total energy by about as much as adding the same mass of coal.
     
    Though very strong, pure graphene is about as brittle as ceramics, so wouldn’t contain an explosion as well as more resilient material like nylon or aramid fiber.
     
    It’s important to understand that explosives don’t necessarily, or usually, contain a lot of energy compared to slow-burning fuels. TNT, for example, has about 1/8th the energy density of coal.
     
    What distinguishes explosives from typical fuels is that explosives can release their energy is much less time than fuels – that is, they have high power.
  5. Like
    CraigD got a reaction from ChrisM2833 in An Organized Look At Creating Nerve Gear   
    Welcome to Hypography, Panther. That’s an impressive and well-organized first post. :thumbs_up
     
    I think I’m pretty much on the same page as you. I don’t think that a system based on a brain-computer interface is doable anytime soon, but that a system based on screens, speakers, and body position sensing and affecting systems, are.
     
    Here are a few key points you may not have considered:
     
    Sight
    Device like the Oculus Rift are impressive, but even if their resolution were increased beyond that of the human eye, and their “screen door” artifact corrected, they’re still limited in a way that prevents reaching the “full dive” level of immersion goal. Like any stereo-optical system, it must either have an infinite focal length, or a fixed depth of field, neither of which is realistic. A device like the Rift allows you to change where you are looking by moving your eyes and/or head, but unlike normal vision, you can’t change the point at which your eyes are focused.
     
    A perfectly realistic sight simulator would need to be holographic – that is, it would need to nearly exactly reproduce not simply frequency, amplitude, and spatial arrangement of light, but also its phase. Such technology exists now – LEIA 3D products looks to me to be the best, but are yet to be available in a consumer product. Online images of these displays looks much improved since this 2011 and this 2013 article about MIT lab projects. Although both the MIT and the LEIA system accomplish the same thing – precise electronic control of the phase of light – the systems are different, the earlier MIT system frontlit, the LEIA backlit.
     

    As we’ve discussed in many posts in this forum, Emotiv’s EPOC is just a low cost dry EEG device, with fewer electrodes than the best quality wet electrode medical EEGs. It’s ability to control anything is pretty limited, so he designers of the few games that use it and similar devices have incorporated it as a feature like “using the force” or “exerting magic”, not mundane, realistic things like moving your limbs. This is an innate limitation of EEGs, not something that can be improved with improvement in the devices, so I don’t think systems like this are of much use in immersive VR. 
    I think the full body suite is the only approach likely to be doable soon. I described this in a few posts, such as this one, calling it a “deep dive waldo” system. Such a system was described in fairly great detail in Ernst Clines 2011 novel Ready Player One, which, if the planned 2018 movie adaptation is as faithful to the book and as popular as I hope, should be much better publically known soon. Note some of the safety concerns I raised in this post – the basic worry, raised more than 50 years ago, is that a system forceful enough to give a realistic feeling of force feedback and input would also, if they system malfunctioned, be forceful enough to cause serious injury.
     
    If we’re going to use a work of fiction as a guide in realizing a deeply immersive VR system, I think Ready Player One is a better one than Sword Art Online. Unfortunately, the hardware in RPO is bulkier and costlier than in SAO, but it’s in principle possible, while as described in the fiction, SAO’s is not.
     

    I’m a 56-year-old computer programmer. I’ve played various things with strings and frets since I was 15 (the less we speak of my occasional forays into thing with strings but without frets, the better :( ). I fenced in high school, and in college and later had a lot more fun doing mock medieval combat in the SCA. Like nearly everyone who posts in this forum, I’m a SAO fan, though I like my sword fighting, and physics in general, more realistic than the anime’s.
  6. Like
    CraigD got a reaction from TrollD3 in An Organized Look At Creating Nerve Gear   
    An “adaptive” video system like you’re describing would need to detect more than just the movement of your eyes. There are systems that do that now – for example this device
    from IMotions (an overview of this and similar present-day eye tracking technology can be read here)
     
    For a system to be able to detect not just where the eye is pointing, but where it’s focusing, the system would need to be much more capable, able to detect changes in the shape of the eye’s lens and/or the muscles and tendons controlling it. I don’t think there’s any system that can do that, in realtime, though such measurments are made manually in non-realtime via may techniques when managing eye health and disease.
     
    Though I think holographic displays like the LEIA 3D are closer to being usable right now, and would be immune to distortions due to latency (the amount of time the system takes to process the eye data and change the display), an eye-reading system would give the game/VR developer the ability to know exactly where the user is looking, which could be useful. The two systems could be combined, a true holographic display giving the highest quality sight simulation, while the eye-reading system gave the program information not usually available in the real world. Consider that without at least a eye-position tracking system, our VR system would be unable to simulate the user using an eye position tracking system (ie putting on IMotion Tobii glasses) in the VR world.
     

    We know with near certainty that present day BCIs, even ones using surgically implanted electrode arrays, can’t control much very well, so I think we need to focus on the body suit and other non-brain-penetrating system being used for essentially all the controlling. 
    It’s dangerously easy, I think, especially after watching or reading fiction describing body suite-based VR systems that work well, to fail to appreciate how hard it is to do this.
     
    Consider an ordinary activity like sitting down and typing this post. The body suite would need to detect the angle of my knees, pelvis, spine, and other parts, pushing against my leg muscles with precisely the 750 N or so force those muscles are using to smoothly move me into my chair. The gloves part of the system would then need to give me “taps” of around 0.001 N in my fingertips to simulate the feel of my keyboard.
     
    The suite needs to be both as powerful as the typical lifting machine, and as sensitive as a lab scale. We’re not talking about just a thin, clothing-like garment with arrays of small electronic actuators, but something like this backed up by an exoskeleton controlled by motors that are at the same time precise, powerful, and able to move as fast as I can move my limbs – in short, a mechanical device about the size of and as good as a human body, well-integrated into a computer system functionally as capable as my brain’s sensory-motor cortex.
     
    Consider another simple scenario, standing in place and jumping up and down. Each launch and landing needs to send a few 1000 Ns of force vertically through the bottoms of my feet, while applying smaller forces realistically to my spine, neck, head, arms, etc. If you begin to model it, this is some complicate motion, with multiple possible simulation solutions.
     
    A first-generation system wouldn’t, or course, have to do this perfectly – for example, it could avoid the need for motors by limiting the VR world to one where my avatar’s body had no inertia, so never felt the push of gravity or impact with objects, but it won’t be truly immersive, as such a world wouldn’t feel very like the real one.
     
    Another issue is that, assuming we’ll be using the system on planet Earth, not conveniently in the microgravity of space, the system will have difficult replication the feeling of the absence of the force of gravity. There simply in no known technology that can “cancel” the force of gravity the parts of the body responsible for orientation and balance sense. The weightless feeling of jumping off a high place or being in space may be beyond any non-BCI system – though a system that has a few vertical meter to move in, like a present day motion ride, might be able to trick, as I described experiencing in this post.
     
    I think there’s a lot of hard work to be done to develop a deeply immersive VR system, via almost any approach, and, fortunately, very fun work. :)
  7. Like
    CraigD got a reaction from TrollD3 in An Organized Look At Creating Nerve Gear   
    Welcome to Hypography, Panther. That’s an impressive and well-organized first post. :thumbs_up
     
    I think I’m pretty much on the same page as you. I don’t think that a system based on a brain-computer interface is doable anytime soon, but that a system based on screens, speakers, and body position sensing and affecting systems, are.
     
    Here are a few key points you may not have considered:
     
    Sight
    Device like the Oculus Rift are impressive, but even if their resolution were increased beyond that of the human eye, and their “screen door” artifact corrected, they’re still limited in a way that prevents reaching the “full dive” level of immersion goal. Like any stereo-optical system, it must either have an infinite focal length, or a fixed depth of field, neither of which is realistic. A device like the Rift allows you to change where you are looking by moving your eyes and/or head, but unlike normal vision, you can’t change the point at which your eyes are focused.
     
    A perfectly realistic sight simulator would need to be holographic – that is, it would need to nearly exactly reproduce not simply frequency, amplitude, and spatial arrangement of light, but also its phase. Such technology exists now – LEIA 3D products looks to me to be the best, but are yet to be available in a consumer product. Online images of these displays looks much improved since this 2011 and this 2013 article about MIT lab projects. Although both the MIT and the LEIA system accomplish the same thing – precise electronic control of the phase of light – the systems are different, the earlier MIT system frontlit, the LEIA backlit.
     

    As we’ve discussed in many posts in this forum, Emotiv’s EPOC is just a low cost dry EEG device, with fewer electrodes than the best quality wet electrode medical EEGs. It’s ability to control anything is pretty limited, so he designers of the few games that use it and similar devices have incorporated it as a feature like “using the force” or “exerting magic”, not mundane, realistic things like moving your limbs. This is an innate limitation of EEGs, not something that can be improved with improvement in the devices, so I don’t think systems like this are of much use in immersive VR. 
    I think the full body suite is the only approach likely to be doable soon. I described this in a few posts, such as this one, calling it a “deep dive waldo” system. Such a system was described in fairly great detail in Ernst Clines 2011 novel Ready Player One, which, if the planned 2018 movie adaptation is as faithful to the book and as popular as I hope, should be much better publically known soon. Note some of the safety concerns I raised in this post – the basic worry, raised more than 50 years ago, is that a system forceful enough to give a realistic feeling of force feedback and input would also, if they system malfunctioned, be forceful enough to cause serious injury.
     
    If we’re going to use a work of fiction as a guide in realizing a deeply immersive VR system, I think Ready Player One is a better one than Sword Art Online. Unfortunately, the hardware in RPO is bulkier and costlier than in SAO, but it’s in principle possible, while as described in the fiction, SAO’s is not.
     

    I’m a 56-year-old computer programmer. I’ve played various things with strings and frets since I was 15 (the less we speak of my occasional forays into thing with strings but without frets, the better :( ). I fenced in high school, and in college and later had a lot more fun doing mock medieval combat in the SCA. Like nearly everyone who posts in this forum, I’m a SAO fan, though I like my sword fighting, and physics in general, more realistic than the anime’s.
  8. Like
    CraigD got a reaction from LaurieAG in The Computer That Can Help Humanity In Science Forever.   
    Which gave rise more 40+ years ago (It was old in 1978) to a famous jingle, commonly called “The Programmers Lament” which remains poignant to this day:
    I really hate this damned machine
    I wish that they would sell it.
    It never does quite what I want
    But only what I tell it.
  9. Like
    CraigD got a reaction from Dubbelosix in How Gravity Works   
    That, at least, we can fix :)  

    Since it has no sound, the sketch doesn’t change, and the text that scrolls across it is small, I think you’d do better with simple text rather than video. 
    Here’s what you wrote, formatted and punctuation corrected slightly:
    A quark is a particle of extremely dense space time Its density puts a squeezing effect on the surrounding space time that it exists in The squeezing effect creates its gravity field and is stronger the closer to the quark A planet creates a gravity field of its own from the astronomical number of quarks in the planet When the Edge of a quark’s gravity field and the edge of a planet’s gravity field touch the gravity field of the quark is squeezed on its edge This pulls the quark in the direction of the planet’s gravity field The quark is continuously pulled in as the lavers of space time are denser the closer to the planet The most obvious problem I can see with your claims, Trevor, is that you’ve failed to include anything except quarks being subject to the force of gravity, but it’s been clearly shown that other particles, such as photons, are also subject to it. 
    Charged particles, such as quarks and electrons, are also predicted by all widely known theories of gravity to be subject to it, but this is difficult to show with simple experiments, because the force between charged particles is so much stronger than that of gravity.
     
    Here’s a learning opportunity: you mention that a planet has an “astronomical number of quarks”. Consider the planet Earth, which has a well-experimentally measured mass, and the up and down quark, which are the quarks contained in the protons and neutrons making up ordinary matter. What do calculate, approximately, the number of quarks contained in the Earth to be :QuestionM
     
    (Sources: Wikipedia articles Standard Model, Fundamental interaction)
  10. Like
    CraigD got a reaction from JMJones0424 in Do Animals Suffer From Boredom ?   
    It’s widely accepted by pet owners and animal scientists both that most or all mammals can suffer from boredom. This is especially important in pets, because boredom can lead to misbehavior, such as destroying their owners stuff.
     
    Interestingly, perhaps because it’s so widely believed, there hasn’t been a lot of tightly controlled scientific testing of boredom in animals. The authors of the 2012 paper described in this ScienceDaily article, about an experiment testing boredom in caged minks, claims it’s the “first study to empirically demonstrate boredom in confined animals”.
     
    I have a pet box turtle, and often wonder if he is capable of experiencing a mental state that could reasonably be called boredom. He becomes inactive after eating, and if I let his temperature drop below 16 C during winter months, will hibernate, but I don’t think he “feels bored” during such inactivity. Boredom, I think, must involve some sort of unhappiness. While my turtle seems capable of arousal (such as when he hunts for bugs) fear (such as when I surprise him changing his food or water), and as mentioned, inactivity, I can’t don’t think “unhappy” or “bored” is in his emotional repertoire.
     
    It would be interesting, I think, to test many different animals for their capacity for boredom and other emotions known in humans, but as far as I know, no such study has been done. Perhaps such a categorization is too ill defined and soft for behavioral science.
  11. Like
    CraigD got a reaction from hazelm in Fire And Water Silhouettes   
    In science, I don’t think it makes much sense to treat fire and water as distinct elements. This idea was popular in Greece ca. 450 BC, when it was proposed that all mater was made of mixtures of the 4 classical elements, earth, water, air, and fire. By 1820, this idea had been completely rejected in favor of the theory we have today, where fire is the plasma state of matter, and water is a compound of the elements hydrogen and oxygen. 
    Lavoisier was ‘da man! Well, no, actually he still considered a sort of fire-like stuff, “caloric”, to be an element alongside hydrogen or carbon, and light to be an element, too, so while some call him the “father of modern chemistry”, he hadn’t entirely split from those ancient Greek natural philosophers, though he was headed in the right direction.
  12. Like
    CraigD got a reaction from Turtle in Sorting Aggregates   
    Assuming all the particles to be filtered have similar densities, you can make a sort of filter that doesn’t truly refuse, but slows, passage of the smaller particles, by having them fall or rise through a container of gas or liquid of lesser or greater density than the particles.
     
    For example, drop an aggregate of small and large stones into a pool of water, and the large stones reach the bottom first. The drawback to such a filtering (or sorting) scheme is that you’d have to work fast to remove the big stones from the bottom of the pool before the small ones caught up, and the aggregate was back to being an aggregate.
     
    If you can impart the same initial velocity, with a non-zero horizontal component, to the aggregate, you can sort by size without the need to work fast. For example, throw the aggregate horizontally through the air (ie with a catapult, cannon, or similar machine) over a soft field (where they stick where they hit, rather than bouncing) and the smaller stones, more slowed by air resistance than the larger ones, will land sooner and closer to the launcher than the large ones.
     
    An etymology (word origin) purist would take issue with such schemes being called filters, because coming from the same source word as “felt”, a filter arguably must be made of or resemble fabric. Since we’ve already accepted mass spectrometers (which are arrangements of charge-particle deflecting magnets), I think we’re past such purism.
  13. Like
    CraigD got a reaction from AmishFighterPilot in Sorting Aggregates   
    Assuming all the particles to be filtered have similar densities, you can make a sort of filter that doesn’t truly refuse, but slows, passage of the smaller particles, by having them fall or rise through a container of gas or liquid of lesser or greater density than the particles.
     
    For example, drop an aggregate of small and large stones into a pool of water, and the large stones reach the bottom first. The drawback to such a filtering (or sorting) scheme is that you’d have to work fast to remove the big stones from the bottom of the pool before the small ones caught up, and the aggregate was back to being an aggregate.
     
    If you can impart the same initial velocity, with a non-zero horizontal component, to the aggregate, you can sort by size without the need to work fast. For example, throw the aggregate horizontally through the air (ie with a catapult, cannon, or similar machine) over a soft field (where they stick where they hit, rather than bouncing) and the smaller stones, more slowed by air resistance than the larger ones, will land sooner and closer to the launcher than the large ones.
     
    An etymology (word origin) purist would take issue with such schemes being called filters, because coming from the same source word as “felt”, a filter arguably must be made of or resemble fabric. Since we’ve already accepted mass spectrometers (which are arrangements of charge-particle deflecting magnets), I think we’re past such purism.
  14. Like
    CraigD got a reaction from JMJones0424 in Could A Person Drown From Steam In A Shower?   
    “Could a person drown from steam in a shower?” is an interesting question.
     
    By the conventional medical definition of “drown”, the answer’s a clear NO. “Drowning” mean “respiratory impairment from being in or under a liquid”. The steamy air in a shower – a mixture of gasses, water vapor and droplets – isn’t a liquid, so can’t be the cause of drowning.
     
    If we broaden the definition of drowning to something like “respiratory impairment due to water in the lungs”, we can sketch some scenarios where a person might have respiratory distress, or even death, due to showering.
     
    I’ve noticed that I sometime cough when breathing deeply in steamy shower, which I guess is due to the water vapor and droplets tickling my trachea, triggering the cough reflex. The coughing prevents water from condensing and running down my airways into my lungs. It’s not normally harmful to get clean water in your lungs this way, because the lungs can absorb not only oxygen, but liquid water, so even without the coughing, even if I deep-breathing steam showered for hours, my lungs wouldn’t fill with water, drowning me.
     
    A person with an illness or disease that impaired the lungs’ ability to absorb water might not do so well.
     
    A person also might get much more water in their lungs in a shower by directly inhaling the water streaming from the shower head. This wouldn’t be pleasant or easy – in my experience from doing this accidentally, the cough reflex is so powerful it would be difficult to intentionally continue – but people can force themselves to override their reflexes to so some intensely weird things, so I wouldn’t say it’s impossible.
     

    The main reason most internet discussion of this have concluded it’s an urban myth is that the amount of liquid water in the volume of steam that a person can inhale in the typical duration of a shower is too low to fill the lungs. 
    At normal atmospheric pressure, steam has a maximum (saturated) density of about 0.590 kg/m3. An average person breaths at an average rate of about 0.00015 m3/s. Most lungs have a total volume of 0.004 to 0.006 m3. So a person inhaling fully saturated steam, who’s lungs are unable to absorb any water, would fully fill their lungs in about 15 hours. A steamy shower is less than fully steam saturated, so this time would be longer.
     
    A person who’s lungs can’t absorb water is likely to have a pulmonary edema, so their lungs would be filling with fluid whether they breath steam or not. Even when this happens, people reflexively cough, expelling the fluid.
     
    So the only scenario I think could lead to respiratory arrest due to breathing steam would require that they have pulmonary edema – perhaps by hyper-hydrating them with an IV line – and their cough reflex being suppressed – perhaps by anesthetizing them, or inducing a coma with drugs.
     
    A good thing to do with stories like this is to try to track down the source of the story. In some cases, it’s from speculation like I’ve made, which someone misreport as an actual medical case. Do you have a link to the place you heard this story, Lisa :QuestionM
     
    Sources: http://www.engineeringtoolbox.com/saturated-steam-properties-d_457.html, http://en.wikipedia.org/wiki/Respiratory_rate#Normal_range, http://en.wikipedia.org/wiki/Tidal_volume, http://en.wikipedia.org/wiki/Pulmonary_edema
  15. Like
    CraigD got a reaction from NimrodTheGoat in The Great Spam Storm Of 13-14 July 2012   
    As anyone who checked What’s New between about midnight and about 10 AM EDT today is surely aware, we’re in the midst of a spam storm or unprecedented proportions: over 400 posts from 40 new registrations, hawking mostly, it seems, rugby videos. The bulk of them appear to be coming from Bangladesh. Our registration questions and CAPCHAs seem to be no barrier to them, suggesting there are humans involved in this assault.
     
    Where, in the past, spammers seem to me to have generally tried to sneak their crap somewhat inconspicuously among legitimate posts – graffiti on bathroom walls, as it were – this wave is like a carpet bombing of junk mail, intent on rendering our site into a heap unrecognizable as its former self.
     
    For the moment, all we moderators can do is knock these posts down as soon as we notice them – a daunting task, as there seem to be many more of them than of us, and we all have better things to do with our time than clean up after these cybervandals. The tools our forum software (which I’ve long griped about and daydreamed of replacing with more functional stuff) offer to automatically combat spam are deployed to their max, but aren’t much help, having automatically blocked only about 15% or these registrations.
     
    Oh, how I’d love to find a way to punish the folk responsible for this: hit whoever’s profiting from it (for I’m certain money-making is behind it all) with an expensive consequence. Alas, I’m neither a lawyer nor someone rich enough to have lawyers at my beck and call.
     
    If anyone has any ideas along these lines, please brainstorm them here.
     
    We’ve long described hypography as like a common living room, and spammers as pests that post adds on the front door (vs. trolls, who come inside and piss on the floor).
     
    These spammers are really pissing me off! :angry:
  16. Like
    CraigD got a reaction from Super Polymath in Alien Intelligence   
    You seem to be moving from the question of “are we being kept in a zoo by an advances alien species?” to “are we in a computer simulation.” Both are worthwhile questions, but I think it’s better to discuss one of them at a time. We’ve had some discussion (but, surprisingly since the idea has been so well-known as to be practically main-stream for night-on 15 years) in these threads, going back more than 10 years: Infinite recursive Simulated Realities and it's implications for the GUT; What Would Be Proof Of A God Or Gods Running The Universe?; Reality Vs Illusion; and What If We're Simulants. There might be more – these are just threads mentioning Bostrom’s simulation hypothesis that I’ve posted in. 
    Let’s stick with the alien zoo question in this thread.
     

    I’m for the mutation rather than ET genetic engineering explanation of human chromosome 2 that caused us H. Sapiens to have 23 chromosome pairs rather than the 24 the other great apes have. I’m also very skeptical of a connections between this genetic event and the traits that make us so dramatically smarter than our ape cousin species, because the timing is wrong – human chromosome 2 appeared 4,000,000 to 800,000 years ago, but behavioral modernity – us getting so smart – appeared much later, 80,000 to 40,000 years ago. Non-deleterious chromosome fusing mutations occur occasionally in humans – the most common kind, Robertsonian translocation, occurs in about 1 in every 1000 babies – and such people are physically and behaviorally normal. If enough of them were in the same place, the changed chromosome count might breed true, and humans 10,000s of years from now might have 22 rather than 23 chromosome pairs. See this article for more (beware - an important link in it, to Bo Wang's 2013 "Case Report: Potential Speciation in Humans Involving Robertsonian Translocations", is broken – use this link to its archive.org snapshot) 
    I hear a lot of silly stuff, especially as my wife and I have lately taken to recreationally surfing YouTube, which she calls “short attention-span TV”. This WhatCulture video reported an I-hope-inaccurate-but-I-fear-accurate survey result that 5% of US voters believe Queen Elizabeth and Barack Obama are shapeshifting reptilian overlords! :( I’m not sure if schadenfreude-y fun on youtube is good for a person, but pretty sure taking the stuff videos like this are making fun of seriously is not.
     

    The Tower of Babel story is IMHO the 2nd nastiest tale of YHWH in the Tanakh, after the Book of Job! From the KJV English translation:Now the whole world had one language and a common speech. As people moved eastward, they found a plain in Shinar and settled there. They said to each other, “Come, let’s make bricks and bake them thoroughly.” They used brick instead of stone, and tar for mortar. And they said, “Come, let us build ourselves a city, and a tower whose top is in the heavens; let us make a name for ourselves, lest we be scattered abroad over the face of the whole earth.”
     
    But the Lord came down to see the city and the tower which the sons of men had built. And the Lord said, “Indeed the people are one and they all have one language, and this is what they begin to do; now nothing that they propose to do will be withheld from them.
     
    Come, let Us go down and there confuse their language, that they may not understand one another’s speech.” So the Lord scattered them abroad from there over the face of all the earth, and they ceased building the city. Therefore its name is called Babel, because there the Lord confused the language of all the earth; and from there the Lord scattered them abroad over the face of all the earth.
    For all that it’s practically a prototype for an evil-ETs-messing-with-humankind scifi story, it’s a pretty silly one IMO, because despite us humans having had many languages since prehistoric times, we’ve always been pretty good at quickly learning one them. If a nasty god like the one in the Tower of Babel story “confused their language” to bedevil a bunch of people dedicated to a common purpose, I can’t imagine that they just wouldn’t spend a few days to relearn their languages, and settle on one in common. Their problem would be engineering, not communication, as building “a tower whose top is in the heavens” out of thoroughly baked bricks just won’t work. ;) 

    I don’t believe we could. Unlike bones and the rare soft tissue, DNA doesn’t fossilize or preserve well, so most of what we know about human DNA older than 45,000 years we know from comparing intact, present-day DNA of humans to that of other present-day animals. The genetic difference that give us the brain structures that allow us to have the language, symbolic though, and other skills that the other great apes have only the rudiments appear to be many, subtle, and complicated. We assume they appeared due to evolutionary selection rather than genetic engineering because there’s no evidence that genetic engineering has been possible other than by humans, and by us only for about the past 50 years. We don’t find any artifacts from advanced technologies on Earth 1,000,000 years ago, and we don’t see any evidence of advanced technology in outer space. In short, the Fermi paradox.
  17. Like
    CraigD got a reaction from JMJones0424 in Can We Change Human Dna?   
    In evolutionary biological principle, any isolated population will select traits that give a reproductive advantage to the individuals that have them. This selection of traits corresponds to changes in the DNA of the individuals in the population. 
    This process explains why, according to the “out of Africa” theory, populations of humans that became isolated in northern Europe to have slightly different body shapes, skin and hair pigmentation, etc. from their parent populations. That is, it explains the existence of the “races” of humans.
     
    So, a little like how blind cave fish like those in the Amblyopsidae family evolved from isolated populations of sighted ancestors, a sufficiently large population of ordinary humans isolated in a sufficiently large cave could evolve to have traits that better enabled it to survive and reproduce underground – if some key criteria are satisfied.
     
    One key criteria is whether enough generations pass that the populations has traits sufficiently different than the original population to be considered a “monstrously” different race, like the creatures depicted in the 2005 movies The Cave or The Descent.
     
    According of the OOA theory, it took 50,000 to 150,000 years for human populations to evolve to have their present day racial differences, but few people consider any present day race monstrous. For a race of humans like the monsters in The Cave or The Descent to have evolved, I guess the original OOA humans would have had to have taken up isolated living in the cave system in question many 10,000s of years ago. Though this strikes me as unlikely, I wouldn’t call it impossible
     
    Another key criteria is whether the initially isolated population of ordinary humans can survive long enough to reproduce, and their children survive long enough to reproduce – that is, if the population can survive even one generation.
     
    I’m not sure the first generation of humans isolated in a cave could survive. Without sunlight, I suspect individuals would suffer from many severe diseases. Also, caves have dramatically less available food than the usual human habitat, so I suspect an isolated population of humans would simply starve, long before it could have raise children.
     
    Taking a lesson from blind cave fish, I suspect that if a population of humans like those from The Cave or The Descent did evolve, a very special cave would be needed. Because cave have so much less food than the surface, blind cave fish can survive only in cave with strong influxes of plant and animal matter from the surface. By this criteria, the rainwater-fed caves of The Cave is more plausible than the dryer one of The Descent.
     
    Even if it is possible, I doubt humans evolved for underground living would be like the superhumanly strong, vicious monsters from the movies. Rather than strength and aggression, I suspect they’ve evolve specialized, very efficient digestion and metabolism, sacrificing size, muscle strength, and brain size – though they wouldn’t necessarily be less intelligent, social, cultural, or technological than their ancestors.
     
    We present-day humans appear to have evolved along these lines. Since the neolithic/agricultural revolution, about 12500 years ago, we’ve evolved to be good at eating grains and reduced our body and brain sizes to allow more of us to live off a give food supply, all the while inventing writing, science, and everything making up present day culture and technology.
     

    I’m pretty certain this isn’t possible. 
    DNA can be damaged by disease or injury, but can’t change in the way needed for evolution, except from generation to generation. Evolution “works”, because individuals with beneficial gene-carried traits reproduce, while those without and with detrimental traits don’t, resulting in those genes becoming prevalent in the population.
     
    The idea that and individuals genetic information – which we now know is carried in DNA - can be changed in their lifetime is know as Lamarckism. It was pretty much discredited as a scientific theory by 1920.
  18. Like
    CraigD got a reaction from JMJones0424 in What Is A Sun?   
    I’m fairly sure you’re mistaken about this, A-wal. See if you can find a source to back it up. 
    JMJones asks the same thing, less gently. ;)
     
    Though models of the complicated details of how the fusion energy in their cores gets to their surfaces, and how stars’ size and mass vary as they age, especially during interesting explode-y and semi-explode-y phases continue to be evolve, the basics of how that energy is produces, and the balance of it vs self-gravity that determines stars’ rough densities has been well-understood since the late 1950s. See the Wikipedia articles Nuclear fusion, Stellar nucleosynthesis, and Convection zone for more.
     
    I think the biggest theoretical puzzle of stellar fusion was the solar neutrino problem, where the number of neutrinos observed emitted by the Sun was almost exactly 1/3rd the amount predicted by the theoretical models. This discrepancy led not to changes in theories of nuclear fusion, but in the nature of neutrinos, specifically support for the theory of neutrino oscillation, where a flavor of a neutrino changes between 3 kinds, so that 2/3rds of the electron neutrinos emitted by solar fusion are on of the other 2 flavors – muon or tau – when they reach detectors on Earth.
     

    The trouble with fusion power is not that we can’t artificially produce in a small device more energy than used for a short period – fusion bombs to that quite well – or that long, even power output is impossible in a very large “device” – nature does this very well with stars – but that we can’t make a small device with long, even power output.  

    Me too. My work for the past few weeks has me up morning and late nights, napping during the day, and other weirdness that confusing my circadian rhythms no end. Right now, I need to try to stay up for a few hours so I can work from 9:00 PM to 4:00 AM tomorrow, then go to a big, social meeting 5 hrs later. How to do this without being weirdly giddy in public is challenging. :)
  19. Like
    CraigD got a reaction from JMJones0424 in What Is A Sun?   
    If for every star, there must be a black hole, we’d need a lot more black holes than are thought to exist. 
    Because the only known way black holes are formed is by the collapse of large stars, and because only about 1 in every 1,000 stars is massive enough to form a black hole at the end of the shiny phase of its life, there are about 1,000 times more stars than black holes. (source: HubbleSite.org’s “how many black holes are there?”)
     
    I have childhood memories of astronomers speculating in the late 1960s through mid 1970s that blackholes were connected via wormholes to “white holes” as an explanation quasars, which at the time were so luminous they defied more prosaic explanation. This seems sort of a scaled-up version of your speculation, Claude.
     
    By the late 1970s, though, as astronomers found and studied more black holes, and over the next decades, as the consensus emerged that practically all galaxies have supermassive black holes at their centers, that the huge accretion disks around the SMBH can become very luminous, and thus that a quasar is just a galaxy with its SMBH in such a state – an active galactic nucleus – this idea was abandoned so thoroughly that few people even remember it. More on it can be found at this Wikipedia section, and in popular astronomy books from those days.
     
    As for the title, a sun (or, as most people call them, a star) is a ball of light elements massive enough to sustain fusion. Nothing like those old proposals for the source of energy for a quasar is needed to explain them, just good old-fashioned nuclear chemistry. :)
  20. Like
    CraigD got a reaction from spartan45 in What are you listening to right now?   
    Heard this pretty, sad song years ago, and walking under yesterdays dark, mean, rainy Maryland skys yesterday, had it come to mind, but I couldn't remember all the lyrics or quite how its guitar went, so via the common tech miracle of my phone, listened to it as I walked.
  21. Like
    CraigD got a reaction from JMJones0424 in Warning: Bad Jokes Are Dangerous   
    Some of my favorited jokes are like this one

    "What did the big chimney say to the little chimney?
    "Nothing, chimneys can't talk."
    which the nbcnews article gave as an example of a “bad joke”. 
    I like these kind of jokes. Their humor comes from making, then rejecting, a silly assertion – in the example case, “chimneys can talk”.
     
    My favorite joke of this kind is

    A physicist, a rabbi, and a dog walk into a bar.
    The dog says, “bartender, gimme a beer.”
    The bartender says “holy *[email protected]#, a talking dog!
    This joke sets up then knocks down the assertion that dogs can talk, then sets it back up, then knocks the assertion that if dogs did talk, people would be unsurprised, then defies the listeners’ expectation of the structure of a joke by abruptly ending without resolving the various cliché elements it introduces.
     
    It does seem to annoy people, though I’ve never been attacked over it – maybe because of my imposing presence. ;)
  22. Like
    CraigD got a reaction from JMJones0424 in Atoms And Singularities   
    I’m guessing you mean black hole – something so massive light can’t escape from it – rather than gravitational singularity, a point where the gravitational force is infinite. 
    A few answers come quickly to mind
    if the inside of an atom, or just the nucleus of an atom, was within a black hole, we wouldn’t be able to get information out of it, so couldn’t discover its internal structure in the ways we have, such as using Deep inelastic scattering. since the force is between charged particles is carried by virtual photons, which like observed photons, can’t escape from a black hole, atoms or nuclei inside black holes couldn’t interact electrostatically. Electrons wouldn’t be attracted to nuclei inside black holes, and molecules couldn’t form out of atoms inside black holes. Chemistry wouldn’t work. According to the Schwarzschild metric, its mass would have to be much larger than we observe. For a black hole with an event horizon radius of a proton (about 8.5 x 10-15), its mass would have to be about 6 x 1011 kg, about 100 time the mass of the Great Pyramid. For one the size of a hydrogen atom (about 5 x 10-11 m), it would be about 3 x 1016, the mass of a small asteroid. This makes me pretty sure atoms or atomic nuclei aren’t inside very small black holes. 
    The question reminds me a little of recent theories proposing that quantum entangled particles are connected by wormholes, such as described in this article. This may explain how measuring one entangled particle implies instant communication with the other, even though they may be far from one another – they are actually zero distance apart within their wormhole. It also hints at the cause of gravity, though I don’t understand the idea well enough to understand this part of it.
  23. Like
    CraigD reacted to sanctus in Who's Afraid Of Gmo?   
    Do you read anything we write? We explained already extensively (see page 6) what the resistance to round-up is and that it IS NOT a chemical. So do not state the same thing over and over without trying to support your claim.
     
    ADMIN-notice: count this as a warning!
  24. Like
    CraigD got a reaction from sanctus in Atoms And Singularities   
    I’m guessing you mean black hole – something so massive light can’t escape from it – rather than gravitational singularity, a point where the gravitational force is infinite. 
    A few answers come quickly to mind
    if the inside of an atom, or just the nucleus of an atom, was within a black hole, we wouldn’t be able to get information out of it, so couldn’t discover its internal structure in the ways we have, such as using Deep inelastic scattering. since the force is between charged particles is carried by virtual photons, which like observed photons, can’t escape from a black hole, atoms or nuclei inside black holes couldn’t interact electrostatically. Electrons wouldn’t be attracted to nuclei inside black holes, and molecules couldn’t form out of atoms inside black holes. Chemistry wouldn’t work. According to the Schwarzschild metric, its mass would have to be much larger than we observe. For a black hole with an event horizon radius of a proton (about 8.5 x 10-15), its mass would have to be about 6 x 1011 kg, about 100 time the mass of the Great Pyramid. For one the size of a hydrogen atom (about 5 x 10-11 m), it would be about 3 x 1016, the mass of a small asteroid. This makes me pretty sure atoms or atomic nuclei aren’t inside very small black holes. 
    The question reminds me a little of recent theories proposing that quantum entangled particles are connected by wormholes, such as described in this article. This may explain how measuring one entangled particle implies instant communication with the other, even though they may be far from one another – they are actually zero distance apart within their wormhole. It also hints at the cause of gravity, though I don’t understand the idea well enough to understand this part of it.
  25. Like
    CraigD got a reaction from petrushkagoogol in Do Animals Suffer From Boredom ?   
    It’s widely accepted by pet owners and animal scientists both that most or all mammals can suffer from boredom. This is especially important in pets, because boredom can lead to misbehavior, such as destroying their owners stuff.
     
    Interestingly, perhaps because it’s so widely believed, there hasn’t been a lot of tightly controlled scientific testing of boredom in animals. The authors of the 2012 paper described in this ScienceDaily article, about an experiment testing boredom in caged minks, claims it’s the “first study to empirically demonstrate boredom in confined animals”.
     
    I have a pet box turtle, and often wonder if he is capable of experiencing a mental state that could reasonably be called boredom. He becomes inactive after eating, and if I let his temperature drop below 16 C during winter months, will hibernate, but I don’t think he “feels bored” during such inactivity. Boredom, I think, must involve some sort of unhappiness. While my turtle seems capable of arousal (such as when he hunts for bugs) fear (such as when I surprise him changing his food or water), and as mentioned, inactivity, I can’t don’t think “unhappy” or “bored” is in his emotional repertoire.
     
    It would be interesting, I think, to test many different animals for their capacity for boredom and other emotions known in humans, but as far as I know, no such study has been done. Perhaps such a categorization is too ill defined and soft for behavioral science.
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