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Sensei

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Everything posted by Sensei

  1. If you would merge two layers of polarization filters. One with e.g. p-polarization, and second one made by material which is able to rotate polarization vector due to applied electric or magnetic field, in such a way that will be opposite axis e.g. s-polarized. They working together would be creating opaque (black) material on demand. https://en.wikipedia.org/wiki/Pockels_effect "Pockels cells are used in a variety of scientific and technical applications. A Pockels cell, combined with a polarizer, can be used for switching between no optical rotation and 90° rotation creates a fast shutter capable of "opening" and "closing" in nanoseconds. The same technique can be used to impress information on the beam by modulating the rotation between 0° and 90°; the exiting beam's intensity, when viewed through the polarizer, contains an amplitude-modulated signal. This modulated signal can be used for time-resolved electric field measurements when a crystal is exposed to an unknown electric field.[2][3]"
  2. Chickens require less nutrients to grow up than pigs and cows (which also produce methane gas). They are also cheaper and healthier for customer. Fish farms are better for environment than fishing of wild fishes. Their population is under control of human. Fish farm does not deplete natural population of fishes, so they can reborn. https://www.fcrn.org.uk/research-library/feed-conversion-efficiency-aquaculture-do-we-measure-it-correctly "Higher protein or calorie retention means higher efficiency. The results show that, on average (weighted according to global production levels of the nine aquatic species studied), 100 g of protein in aquaculture feed will be converted into 19 g of protein for the human food supply (19% retention), and that 100 kcal of aquaculture feed will be converted into 10 kcal for the human food supply (10% retention). Protein retention ranges from 14%–28% for the aquatic species studied, and 13%–37% for the land species. Calorie retention ranges from 6%–25% for the aquatic species and 7%–27% for the land species. The best performers across all species considered are chickens, followed by Atlantic salmon."
  3. You can use Wolfram Alpha to plot two graphs, so you can see whether and/or where they are crossing each other.. https://www.wolframalpha.com/input/?i=f(x)%3Dx^2%2Cf(x)%3D16^x With limits x = -1 ... +1 https://www.wolframalpha.com/input/?i=f(x)%3Dx^2%2Cf(x)%3D16^x+for+x%3D-1+to+%2B1
  4. You are mistaken over-trusting DNA, to catch true murderer after many years. Because it might be as well misused against incorrect innocent person. I will give you examples how it can put somebody innocent to jail, or even sentenced to death, or life in prison: - imagine you have girlfriend, or girl for one night met at club, have sex with her at night, she is going early to job, leaves your apartment early and somebody is attacking her in the middle of route, but leaves no his DNA, or leaves DNA. Now, police officers are checking DNA on the body, and find it is yours. Are you murderer? Are you rapist? Did you participate in multi person rape on her? No, you just had normal sex with her.. But you are unlucky that she has been attacked right after it.. Even worse if police finds out you had argue through SMS or Internet with her, just before somebody else attacked her.. - imagine you are working at mall. Yours responsibility is to put bottles with beer, wine, vodka, whisky etc. to refrigerator or simply on shelf. Client takes bottle. And many hour later it is used by somebody on the party as weapon (broken bottle), and somebody dies due to injures. Again, police officers are checking tool used to commit murder, and find out your DNA on it... Again, you can be mistakenly sentenced by court, innocent person put to jail, thanks to DNA found on tool used to committing crime.. If police had your DNA because you are in database already, they will find you immediately, and you have immediate troubles, but if not, they have "trace", and many (dozen) years later DNA from that crime scene can be compared with your DNA and match! Match, but not the true murderer! ps. My post is not against "statue of limitations" nor for it.. but just not to have absolute trust in DNA, even if it matches..
  5. I think that the key word here is personal... Audio files made by 3rd party musicians are not your personal files.. Everybody around the world can have them..
  6. Bible = Old Testament + New Testament. You should be more specific which part of it, you are interested in. Generally, Old Testament "suspicious" sources were kept, and New Testament "suspicious" sources were destroyed (or attempted to be destroyed). https://en.wikipedia.org/wiki/New_Testament_apocrypha https://en.wikipedia.org/wiki/Pseudepigrapha https://en.wikipedia.org/wiki/Biblical_apocrypha
  7. I was just reading this article prior writing my reply.. Word "perfect" has bad connotations for me. Somebody "perfect" cannot being more enhanced, in contrary to "master".
  8. Apart from cancer, pollution of air can cause pneumoconiosis. https://en.wikipedia.org/wiki/Pneumoconiosis Dust obviously has the highest concentration in coalmines, silica mines, factories processing ores and surrounding them areas. Therefor industry workers are the most affected by it. "In 2013, it resulted in 260,000 deaths globally, up from 251,000 deaths in 1990.[4] Of these deaths, 46,000 were due to silicosis, 24,000 due to asbestosis and 25,000 due to coal workers pneumoconiosis.[4]" Read pathogenesis section in the above article.
  9. Human can get rid of money and the all evilness associated with them i.e. there will be no thieves, there will be no murders to kill witnesses of stealing, there will be no corruption, there will be no hunger, no people dying unable to buy food, medicament or unable to afford health care, there will be no poor, nor wealthy, no greediness nor jealousy of possession of things you don't have but others have.. no drug dealers, nor drug wars.. People will be well educated, if they will be intelligent enough to use free of charge universities.. In the distant past, people lived in small villages, each other voluntarily helping other members of community because of goodness from the bottom of their hearts..
  10. ...first draw it at the right scale... Sun has radius ~0.7 mln km Distance from the Sun to the Earth is ~150 mln km 150 / 0.7 = ~214 x Have 1920x1080 screen resolution? 1920 is width of the entire screen. 1920 / 214 = ~9 pixels. Draw circle with 9 pixels radius on the leftmost coordinate at x=0... and less than 1 pixel on the rightmost coordinate at x=1919 will be the Earth.. Nonsense. Do you have classical lightbulb in room? It's obeying inverse-square law too. Swansont's comment was about inverse-square law.
  11. ..because for some (majority?) of people money is more important than environment.. ? Isn't what current US government is doing? e.g. giving up Paris agreement, restoration of coal, oil and gas industries at any environmental cost.. etc. etc. "hilariously", miners are the first one to suffer and die due to mining coal, due to dust their lungs are damaged. https://en.wikipedia.org/wiki/Coalworker's_pneumoconiosis "In 2013 CWP resulted in 25,000 deaths down from 29,000 deaths in 1990.[7] Between 1970–1974, prevalence of CWP among US coal miners who had worked over 25 years was 32%; the same group saw a prevalence of 9% in 2005–2006.[14] In Australia, CWP was considered to be eliminated in the 1970s due to strict hazard control measures. However, there has been a resurgence of CWP in Australia, with the first new cases being detected in May 2015.[15] From 1999 to 2016, the average years of life lost due to CWP increased from 8.1 to 12.6 years, most likely due to the increased severity and progression of CWP.[16]" There are labels on cigarettes that "smoking will kill you or cause cancer". That should be put on the road to coalmine as well.. With the above statistics.. ...humans are loving money, themselves, and their families.. By "loving family" they usually mean "responsibility" i.e. family must be fed at any cost.. ..because it does not earn money.. does not feed them and their families.. At least in their simple understanding the world around them.. Africans fishermans complained in TV document that fishes are getting smaller and smaller (than they were 20+ years ago). I watched this TV document, astonished hearing their moaning.. They could not grasp idea that if they catch and kill the all fishes, they cannot grow to be bigger.. They cannot grasp idea that the more people living on the world, the more food they need, the more fishermans needed, the less fishes will be in seas.. and if it continues there will be times that there will be no fishes to catch at all.. I betcha that they will be praying to God(s) for more fishes..
  12. UFO means Unidentified Flying Object. Once it is identified it not a longer U.F.O. It says nothing about whether it comes from Earth or from outer space.
  13. They born on farms, don't know wild life. Farm is their home. Their entire world. Farm (home) is the only place where they feel safe. You would have to first teach them what is difference between "wild life" and "farm" (and what is after farm). In some Europeans countries there is no wild world anymore. Human made buildings every couple hundred meters or less. Everything connected by roads and highways disallowing natural free migration of animals from one area without food anymore, to other area with availability of food or water. Even fish migration is problematic if a dam was built along their natural route (e.g. salmon) (ecologists just start to persuade to build fish ladder). In Europe, releasing animal to the wild, means sudden death just in a couple days, in car accident. Or death in cold winter night, they are not prepared for (because never had to bother about such things on the farm). Replace "farm" by "the Earth", and "wild life" by "galaxy" or "cosmos", and you have pretty much situation with humans. The Earth is too big for majority of people, and prefer staying at home, where they are feeling safe, not to mention cosmic travel. They could meet mind-intercepting aliens during their journey through cosmic space..
  14. You are not using correctly ordered names, so auto-fill/auto-completion cannot work. I am using it every day. In Android Studio (Java) OTOH if you start writing e.g. "permission", IDE is searching this term also inside of name and make it bold. e.g. main_error_insufficient_permissions (so actually it would be sufficient to enter "pe" or "per" to limit list of available results, and pick the right one from drop-down list).
  15. I have deja vu.. Many years ago there was a thread about it..
  16. ...I thought it is called "fruit"... Some plants require/prefer to pass through animal stomach and gastrointestinal tract, and grow up with excrement (fertilizer), a few kilometers away from mother plant.. One could utilize reptile ability to regrow tail, to repeatedly eat part of animal every couple months, without having to kill it.
  17. Yes.. when you have to horizontally scroll text to be able to read them all.. Some prefer "reverse notation".. e.g. main_error_insufficient_permissions so other "main_" strings/variables/classes etc. are listed in alphabetically sorted order together in IDE, and other "main_error_" are listed in sorted order together in IDE, etc.etc. If you have human natural language order, they would be all mixed together. "main" is place where is used specified string (in Android app), "error" is what is subject of specified string. e.g. you have class which has name PasswordEditText, so prefix will be "passwordedittext_" and the all its strings grouped together in strings.xml This has to help them listed together due to sorting algorithm in IDE (auto-fill/auto-completion feature of IDE).
  18. Unless there are some interesting ores on them..
  19. Did you check how small they are? ~ 150 and 280 times smaller than the Earth's Moon..
  20. You can avoid most lung cancers by quitting smoking and giving up burning fossil fuels..
  21. W3Schools has Python tutorial https://www.w3schools.com/python/
  22. I think so, in our deliberations, we can safely exclude outermost layers of the Sun (where the density is less than water on Earth), and concentrate just on the solar core. Mass of the core is 34% of Msun = 0.34 * 1.9885×1030 kg = 6.761*10^29 kg Radius of the core is ~20% of Rsun = 0.2 * 696,342,000 m = 139,268,400 m So, using your above escape velocity from the center of object, we are getting: v2 = 3 * 6.67*10^-11 * 6.761*10^29 / 139,268,400 = ~9.714*10^11 v=sqrt( 9.714*10^11 ) = ~ 985,600 m/s = ~1 million m/s = ~1000 km/s
  23. Escape velocity equation (from surface and further) is: [math]v=\sqrt{\frac{2 G M}{r}}[/math] for any M, we can find any such so small r, after reaching it, escape velocity is equal or exceeding c. So, for the Sun, it'll be: [math]r=\frac{2 * 6.67*10^{-11} * 2*10^{30}}{299792458^2}[/math] approximately 2968 meters. Multiply by millions and billions of years sucking in any (hypothetical) DM, and these Msun and Mearth must already have it included.. I think so escape velocity equation has sense only from object's surface and further. If (electric neutral) particle is inside (passing through) of e.g. star or planet or other object, it's attracted from the all directions, and calculation which is just toward center of it, is at least "imprecise".. I said concentration, not quantity. Concentration requires both quantity and volume.
  24. Maybe you should make article and make it sticky what dimension means in physics.. so they won't confuse it with sci-fi vision of other dimensions..
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