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Sensei

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Everything posted by Sensei

  1. I agree with Swansont's statement from #13 post. This paragraph of book is almost certainly wrong.
  2. Okay, I found it on page 74. Thanks for pointers.
  3. in mine version of book (translation from English from 2011) pages 33 to 91 are section "World according to Feynman".
  4. That's not mine speculation! That's whole idea behind multiverse theory. http://en.wikipedia.org/wiki/Multiverse#Level_II:_Universes_with_different_physical_constants Quote "Different bubbles may experience different spontaneous symmetry breaking resulting in different properties such as different physical constants."
  5. Interesting http://en.wikipedia.org/wiki/Hercules%E2%80%93Corona_Borealis_Great_Wall I see one problem with interpretation of it as bubble of other universe - we see it! If we see photons coming from it, it means speed of light is same as in our universe.. In other universe in multiverse theory, speed of light c might (should? because of higher probability) be different than in our own universe. Also astrophysics should perform experiments with neutrinos and other accelerated particles coming from this galaxy cluster to see how different (if different) they are.. I see more rational explanation than bubble of other universe - our Universe might be much older than calculated by us currently.
  6. Professional physicists would concentrate on finding the real answer why constant have value such as Compton frequency. Mathematic analysis supported by indispensable experiments. Propagation of idea of multi universes, parallel universes, bubbling universes (different regions of same universe with different physical constants) is not possible to be experimentally confirmed. So it's not even a science, when you can't make an experiment verifying your theory and you just have to believe..
  7. The Cosmic Landscape by Susskind is about multiverses as answer why some constant have value as we know.
  8. Robotic engineer might need anatomy & biology if he would like to reach state of the art level and create f.e. cyber arm connected to body of human/animal, and controlled by thought.
  9. This is not exact description of mine tv model fix, but pretty similar: http://blog.dr-ivan.com/2010/10/12/how-to-fix-your-lcd-monitor-changing-capacitors/ These capacitors have 1000 uF/25 V and 470 uF/25 V.
  10. I had exactly the same issue with mine LCD tv a few years ago. 1 month after end of warranty (not the first time I had such "accident", like in clock). It turned out to be couple capacitors broken. When I entered exact model name of mine TV in google as keyword, hundred threads about mine issue were the first one in search results.. Some people even took photos with arrows with comments "replace this, this and this". I have done so, components cost $2 or less, and TV is working fine for 6 years now. After unscrewing it, capacitors were immediately visible bold.
  11. Funny accident. I just saw old movie from 1960 on MGM about teacher being accused of teaching Darwin evolution in school. The most of movie is in court where lawyer is fighting with prosecutor and judge (he rejected the all lawyer's witnesses scientists to testify). http://www.imdb.com/title/tt0053946/ "Based on a real-life case in 1925, two great lawyers argue the case for and against a science teacher accused of the crime of teaching evolution." Actually, not a bad movie. Personally I have never met creationist.
  12. It would not differ. People don't understand that Antimatter is indispensable part of our Universe. Our atmosphere is full of pion+, muon+ and positrons (result of decay of two first). They're result of collisions of protons at relativistic velocity in upper region of atmosphere. Positron is also antimatter. Antiparticle of electron. The most common star fusion process is producing positrons: p+ + p+ -> D+ + e+ + Ve Also instable isotopes which have more protons than neutrons are decaying mostly through positron emission (beta decay +) Each banana is emitting 15 positrons per second http://en.wikipedia.org/wiki/Banana_equivalent_dose
  13. Have you read? http://en.wikipedia.org/wiki/Hazard_%28computer_architecture%29 ps. This should be in Homework Help I guess.
  14. Your teacher is right. Even better would be if he show reaction experimentally in lab. What molecules do you know which are made of atoms that you mentioned above? Make a list of them. Quantity of atoms must match on both sides of equation. f.e. H2O + Cl2 -> ... On the left you have: 2 atoms of Hydrogen 1 atom of Oxygen 2 atoms of Chlorine H2O + Cl2 -> HCl + HClO Count atoms on the right side of equation, and you will see exactly the same quantity of atoms as on the left.
  15. Have you read Electrolysis of water article? http://en.wikipedia.org/wiki/Electrolysis_of_water
  16. Dear vasileturcu, read about oil drop experiment. http://en.wikipedia.org/wiki/Oil_drop_experiment It's immediately invalidating your theory. Little description: X-rays passing through oil drop that's failing down due to gravitation of Earth, are ionizing oil drop, because some of its electrons are ejected from atoms. Now oil drop possess positive charge. Charged particle placed in strong electric field is slowing down its movement, stopping movement, or even going backward (oil is going from bottom to top of container), depending what voltage and sign we will provide to plates. If Earth would possess positive charge, it could not work this way. The only sensible explanation is that our planet has pretty much neutral charge.
  17. By "Oxygen used up" they meant that Oxygen is no longer in free gas form O2. When some molecule is "burned", it's oxidized. For example, if you burn methane: CH4 + 2 O2 -> CO2 + 2 H2O There is produced Carbon dioxide and two molecules of water. Process of producing energy from glucose is more complicated than burning methane and has been described f.e. here http://en.wikipedia.org/wiki/Cellular_respiration#Aerobic_respiration CO2 is removed from living organism by Red blood cells. http://en.wikipedia.org/wiki/Red_blood_cell Plants are using CO2 to build their cells, and giving back O2 to atmosphere. Carbon remains in their cells. Read more about photosynthesis here: http://en.wikipedia.org/wiki/Photosynthesis
  18. Example against your theory: 2H2 + O2 -> 2H2O Reactants: 3 total molecules Products: 2 total molecules Reaction is exothermic. Other example: 2 C2H2 + 5 O2 -> 4 CO2 + 2 H2O
  19. Who said mass is infinitesimals? If you have 10 kg of Carbon-12 isotope it means it's 10,000 g / 12 g/mol = 833.3 mol. 833.3 * NA = 833.3 * 6.022141*10^23 = 5.01845 * 10^26 atoms of Carbon in 10 kg. You can read more about it http://en.wikipedia.org/wiki/Avogadro_constant http://en.wikipedia.org/wiki/Amount_of_substance http://en.wikipedia.org/wiki/Mole_%28unit%29
  20. Hello! On wiki page http://en.wikipedia.org/wiki/Isotopes_of_carbon we can read that decay energy of Carbon-11 isotope is 11C -> 11B + e+ + Ve + 0.96 MeV The first one with 0.96 MeV is correct. I am receiving exactly the same value. 11C + e- -> 11B + Ve + 3.17 MeV But this one, I am not so sure whether it's correct. Can someone point me to other sources mentioning this decay energy of Carbon-11 to verify data.. ? The best would be couple independent sources. After posting I found this http://www.nucleide.org/DDEP_WG/Nuclides/C-11_tables.pdf which mentions 1.982 MeV as decay energy of Carbon-11 (decay through electron capture). And that was mine previously calculated value too (so I was quite surprised that it doesn't match wiki page).. Best Regards!
  21. I showed photos what result you should expect by placing polarization filters between LED/LCD monitor and your eyes or camera in this thread http://www.scienceforums.net/topic/80366-particle-location/?p=783255 Polarization is described f.e. here http://en.wikipedia.org/wiki/Polarization_%28waves%29 If we have not-polarized source emitting photons (such as laser, Sun or light bulb) to material that is passing through photons with one polarization, and reflecting photons with opposite polarization, you will know which polarization expect from each new beam of photons. These photons are entangled - measure one beam, and you know in advance what result you will have measuring the other one.
  22. 200 MB of text file is not much. Or do you meant 200 GB? If it's 200 MB, you can load it in a few seconds entire to memory in C/C++ code.. If you're seeking for high performance and file size is not an issue, remember to NOT using while( !feof( file ) ) { fgets() } loop which is loading one row at a time. 200 MB will have millions of lines, and it'll be very slow method. Load file at once, then process from memory. Reading chars from memory is fast, even faster if data is in CPU cache. Reading row by row - slow performance. Make a test, and you will see on your own eyes. There is a way to not have to load whole file at once - by using mapping file to memory functions. But it's OS dependent stuff. I am not sure whether you're writing for Windows. If so, here you have description of memory mapping functions: http://msdn.microsoft.com/en-us/library/windows/desktop/aa366537(v=vs.85).aspx I don't know about excel, but txt the most natural obvious method is C/C++ program that is doing while( !feof( file ) ) { fgets() } loop but as I said it's slow. If you don't mind spending couple minutes each time, go ahead use it. But otherwise load whole file at once to memory. Then search in loop for EOL from current memory location (f.e. use strchr() in C/C++). If you will find it, you have whole row, copy it to some buffer, replacing EOL by 0. The buffer will have the same what fgets() would normally return. Then repeat with the rest of original file, incrementing current memory location to char right after EOL of previous row. I don't understand question. It's you who know what data file contains and what format your program will understand.. That's natural that program must check syntax of row of txt data to check whether it contains errors or not. Otherwise wrong data could trash database or crash application. The most efficient way is writing C/C++ application which is using MySQL or other database functions (the most probably through linked library). When whole file is in memory, and db engine supports multi-tasking, and checking syntax of row is taking a lot of time, you can even make program multi-threaded and speed it up even to the number of threads your CPU has (f.e. 8-12 times faster on Core i7+). Simply 1st thread will be analyzing rows in f.e. 1000000 rows, 2nd thread the next million rows, etc.etc, 12th thread will be analyzing rows with offset 11,000,000-11,999,999) If PHP script has to work on 200 MB file, it sounds like nightmare for performance.. It'll be running hundred if not thousands times slower than C/C++ code, even using while( !feof() ) { fgets(); } loop. Better would be writing CGI program (in C/C++) executed by PHP just to process data.
  23. Interference doesn't destroy wave.. It looks more like this (it's small version of mine animation of interference effect):
  24. Of course I thought about C/C++ as pretty low-level languages. (I even wrote sound card driver for C-Media PCI card 15 years ago) I meant that you don't write driver/OS in f.e. interpreted languages.
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