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DoctorJohnSmith

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  1. Funny
    DoctorJohnSmith reacted to Levent in Is apple just going to kill x86 now?   
    Holy shit. I never expected to see sexual frustration in combination with ARM architecture.
  2. Agree
    DoctorJohnSmith got a reaction from PeterT in Apple, Amazon and Google unite to help create a universal smart home standard   
    This is a big deal imo, considering how fragmented smarthome devices are. 
  3. Agree
    DoctorJohnSmith got a reaction from DededeKirby in Apple, Amazon and Google unite to help create a universal smart home standard   
    This is a big deal imo, considering how fragmented smarthome devices are. 
  4. Agree
    DoctorJohnSmith got a reaction from GDRRiley in Apple, Amazon and Google unite to help create a universal smart home standard   
    This is a big deal imo, considering how fragmented smarthome devices are. 
  5. Agree
    DoctorJohnSmith got a reaction from Techstorm970 in Apple, Amazon and Google unite to help create a universal smart home standard   
    This is a big deal imo, considering how fragmented smarthome devices are. 
  6. Agree
    DoctorJohnSmith got a reaction from SomeRandomDude111 in Apple, Amazon and Google unite to help create a universal smart home standard   
    This is a big deal imo, considering how fragmented smarthome devices are. 
  7. Agree
    DoctorJohnSmith got a reaction from elfensky in Apple, Amazon and Google unite to help create a universal smart home standard   
    This is a big deal imo, considering how fragmented smarthome devices are. 
  8. Informative
    DoctorJohnSmith reacted to tikker in linus tech tips gravity waves.. 6000   
    Alright, I'll take the bait First of all, this video is about gravitational waves which are technically not the same as gravity waves. The former are created by accelerated masses and can only be detected significantly from massive objects such as neutron stars and black holes. Gravity waves are just your every day waves you can see in the ocean, for example.
     
    Now let's move on to using only 2 stations in stead of 3. You are partially correct here in that to start pinpointing an exact location, we would need three or more detectors. Scientists know this, which is why they are planning to build more. However using the combined knowledge of two stations and the dead zones (i.e. zones where the detectors are not sensitive or not sensitive enough), we can estimate an approximate location by e.g. saying we are 90% sure the even happened in this general area. This is then used by follow up telescopes. This area is much larger than the typical area covered by normal telescopes however, which illustrates again the need for extra stations, as this makes it extremely difficult to do a quick enough follow up, since we don't exactly know where to look. An example of this is shown in the following plot. The circle is the sky in a spherical projection. Hours indicate right ascension, which is a horizontal, and the degrees indicate declination, which is a vertical coordinate, if you will. The gray fuss is the Milky Way. Solid black lines inidicate the most probable area of the depicted event from gravitational waves and the other symbols (squares and circles) separately the field of view of telescopes at other wavelengths, and combined the area covered for follow up. It's taken from here: https://www.ligo.caltech.edu/news/ligo20160404 which is a nice read about why more detectors are necessary.
     

     
    Third, your point about vibrations from buildings, vehicles, earthquakes or whatever. The video already explained the measures they take to eliminate as much of the Earth based vibrations as they can. Furthermore, if you see a signal in only one of the stations or the timing for the signal between the stations is off from what you would expect, this can be eliminated as a gravitational wave. Here lies a big part of the power why we can do this: we can exactly calculate what the signal should look like based on general relativity. This is done for a variety of scenarios, and then something called "template fitting" is done, in which the signal is compared to a large database of template events to find the best match. This match can then be further inspected to make absolutely sure, but a having match is already a good sign something happened.
     
    Finally your comment on the speed of light. Laser light moves at, you guessed it, the speed of light. So if anything can detect something moving at light speed, it's lasers. In any case, gravitational waves travel at the speed of light. This means we can exactly predict what the delay between the two detectors in Livingston and Hanford should be. In other words, if we detect a signal at A, we know the same signal has to arrive at B precisely X nanoseconds later. This is the first "line of defense" so to speak, if it does, continue with template fitting to see if we can match it. Finally, nothing can or will ever move faster than the speed of light in vacuum. It's the cosmological speed limit.
     
    So in short, detecting gravitational waves is very much possible nowadays and can be done with only two detectors on Earth. Yes more is bettter, yes bigger is better, yes going to space will be better (and is being worked on, e.g. eLISA), but it's by no means impossible anymore. As a side note, it is possible to recover signals from below the noise floor. Things like GPS rely on it, for example, but that's besides the point here.
  9. Agree
    DoctorJohnSmith reacted to KarathKasun in linus tech tips gravity waves.. 6000   
    So many basic physics principals missed by thus guy that I cant even.
  10. Funny
    DoctorJohnSmith reacted to K i a r a in Don't remember the name of a game   
    oh yea, the game with the car.. and the paths.. that one.
  11. Like
    DoctorJohnSmith reacted to ElSeniorTaco in PC resets randomly   
    Could be a number of things,
    power supply
    heat (seems like we ruled this out, but you need to be sure)
    RAM
    Motherboard
    Overclocking/Instability
    Power button (had one shorting out on me that caused this once)
    One thing I am pretty sure of, it is most likely probably something hardware related.
     
    Where to start?
     
    Cheap stuff first lol
     
    First would be checking heat levels, especially under load, if you get a wiff of heat spikes, you need to re-paste / re-position the heat sink
     
    If that isn't the issue, next try to remove any over clocking
     
    If that isn't the issue, next, start the computer, unplug the power switch wires from the motherboard, see if it happens again
     
    If it keeps rebooting,
    Next, remove all the ram, leave just one stick, see if you can get it to reboot, if it does, try another slot with the same stick
    If it keeps restarting, try another stick of ram,  rotate it into different slots if it reboots on you, then move on to the next stick of ram if this one gives you trouble as well
     
    If all of them give you the same results, next try using a different psu from another computer
     
    If you still get the same issue, its time to strip down the entire computer(although its not a bad idea to start here in the first place)
     
    Remove everything extra, you only want one stick of ram, no gpu (if you have integrated), just the os harddrive, no cd drives, only a keyboard/mouse plugged in
    You want just the bare minimum to get this computer running, try to make it crash under these conditions.
     
    If this doesn't work, you can try resetting cmos
     
    If it continues to crash, and you are sure you have covered all of the above with absolute confidence, then you might have a bad motherboard
     
    Report back with what happened on each step, so we can get some idea of whats been tried and the results of each of those tests
     
    if its rebooting in the way that you mention (random under load and without load), personally I would suspect ram first,  as its been one of the more common causes of this issue in my personal experience 
    But that doesn't rule anything out, test everything, its better to be sure than to assume.
  12. Funny
    DoctorJohnSmith reacted to reniat in I need a name for my PC   
    Jeffrey
  13. Funny
    DoctorJohnSmith reacted to Syntaxvgm in I need a name for my PC   
    Color theme makes it easier. I have a black PC I call 'reparations' and a freind has a white pc in the same case he calls 'privilege'. 
  14. Like
    DoctorJohnSmith got a reaction from Belgarathian in Netflix UHD streaming for Pascal based video cards is in the works   
    the GTX 980, can render games at 4K but can't stream netflix in 4K.
     
    LOGIC
  15. Agree
    DoctorJohnSmith got a reaction from Lurick in ps4 hdd to pc   
    that's not how it works, that's not how any of this works.
  16. Agree
    DoctorJohnSmith got a reaction from shadowbyte in ps4 hdd to pc   
    that's not how it works, that's not how any of this works.
  17. Funny
    DoctorJohnSmith reacted to themctipers in AMD making money from ad revenue from installing drivers!?!?   
    Ryzen with us, V E G A 
     
    nvidia driver installation has advertisements for games in them aswell. 
     
    and nvidia requires you to have a account to use any features over than basic driver support. 
     
     
    amd > nvidia when it comes to software. The fucking drivers are unstable as shit 
  18. Agree
    DoctorJohnSmith reacted to captain cactus in AMD making money from ad revenue from installing drivers!?!?   
    Yup. They went into retard mode with this one.
  19. Funny
  20. Funny
    DoctorJohnSmith reacted to DrMacintosh in Netflix UHD streaming for Pascal based video cards is in the works   
    Of course there is:
     
    $
     
    Its the only thing that matters in society. 
  21. Agree
    DoctorJohnSmith reacted to KenjiUmino in PC doesn't Post - Memory Problems   
    have you tried putting the sticks in A1 and B1?
  22. Like
    DoctorJohnSmith reacted to Kakapipi in ps4 hdd to pc   
    Hey guys
    Is it possible if you plug a ps4 hdd to a pc that you can play games with the pc its cpu and gpu ?
    Like no other hdd, only the ps4 hdd
  23. Like
    DoctorJohnSmith reacted to NSDUO in iPad Air 2 vs new $330 iPad   
    Nah I don't trust google plus it lowers the picture quality 
  24. Agree
    DoctorJohnSmith got a reaction from Lyxes in My problem with forums   
    This is a tech forum
  25. Informative
    DoctorJohnSmith reacted to QuantumBit in its the cutest reference card.   
    GT 10 0? I'm interested.
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