+ Reply to Thread
Page 3 of 283 FirstFirst 1 2 3 4 5 13 53 ... LastLast
Results 41 to 60 of 5649

Thread: Large Hardon Collider     submit to reddit submit to twitter submit to tumblr

  1. #41
    Tottenham 'til I die
    Join Date
    Jan 2008
    Posts
    2,216
    BG Level
    7

    Quote Originally Posted by Mizango View Post
    How so? As in I need an example?

    Theoretical physicist do exactly what he does.
    Have you ever read his books? He just piles speculation on top of speculation. I guess I should put the disclaimer that I'm a third year physics student and I absolutely despise string theory, which is what he bases his speculations on.

  2. #42
    Title: "HUBBLE GOTCHU!" (without the quotes, of course [and without "(without the quotes, of course)", of course], etc)
    Join Date
    Jul 2006
    Posts
    3,142
    BG Level
    7

    Quote Originally Posted by archibaldcrane View Post
    I never understood - if the speed of light is constant, then how can it be bent by gravity? If it's bent by gravity...doesn't that mean it can be accelerated or decelerated by gravity? Doesn't the existence of a black hole mean that light doesn't have a constant speed?
    There's a mathematical law that describes the path light travels. Though it always travels at the same speed, the direction it goes follows a certain rule: It always minimizes a certain integral. Basically, to get from point a to point b, light takes the path through space that will cause it to get there the quickest.

    If you need to get from point A to point B, and you can't speed up or slow down, what's the fastest way to get there? Well, obviously if you were in this situation you'd go in a straight line, because you know intuitively that it is the shortest distance between two points. You've also learned this in geometry.

    The geometry we learn in school is called "Euclidean Geometry", as you probably already know. What you might not know is that the universe isn't always Euclidean. Gravity bends and warps space so that Euclidean geometry is no longer an appropriate way to describe it.

    In any form of geometry, the shortest distance between two points is called a "geodesic". For example, the shortest way to get from the north pole to the south pole on a sphere is traveling directly south with no deviations. Of course, when you're at the north pole, every direction is south, so you would have to pick a direction, and travel that direction along the sphere. But since a sphere is curved, you're not actually traveling in a straight line. So the shortest distance between two points (a geodesic) is not a straight line in this form of geometry.

    When light is near a large gravitational field, the geometry is no longer Euclidean, so the "straight lines" are no longer straight lines. So light travels in "straight lines" instead of straight lines (and by "straight lines" I mean geodesics).

  3. #43
    Insert Witty Title Here
    Join Date
    Jun 2006
    Posts
    6,383
    BG Level
    8

    IIRC there recently was a study in which they actually slowed down and even stopped a photon. I will have to look and see if I can find it.

    If the existence of non-Baryonic matter is in question, is there a more accurate or current theory that explains the non uniform dispersal of matter through the universe?

    Edit: Couldn't find the article but the experiment took place in a Harvard lab.

  4. #44
    Title: "HUBBLE GOTCHU!" (without the quotes, of course [and without "(without the quotes, of course)", of course], etc)
    Join Date
    Jul 2006
    Posts
    3,142
    BG Level
    7

    Quote Originally Posted by zoobernut View Post
    IIRC there recently was a study in which they actually slowed down and even stopped a photon. I will have to look and see if I can find it.

    If the existence of non-Baryonic matter is in question, is there a more accurate or current theory that explains the non uniform dispersal of matter through the universe?
    Experiments that slow down or stop photons don't literally slow down or stop the photon. They store the information that describes the photon, destroy the photon, and create an exact replica of the photon. One experiment managed to stop the beam at a single point in space, and hold the information in a crystal for a few fractions of a second, and then release the exact copy. So they essentially (but not literally) stopped the photon. I can probably find the article in a solid state physics journal and post it for you if I can't find the news article.

  5. #45
    Insert Witty Title Here
    Join Date
    Jun 2006
    Posts
    6,383
    BG Level
    8

    Thanks for clarifying that. It sounds like that is very similar to the experiment where they "teleported" the photon. In that experiment they essentially took in the information of the original photon in and then produced an exact replica in a different spot.

  6. #46
    Title: "HUBBLE GOTCHU!" (without the quotes, of course [and without "(without the quotes, of course)", of course], etc)
    Join Date
    Jul 2006
    Posts
    3,142
    BG Level
    7

    Quote Originally Posted by Woozie View Post
    Experiments that slow down or stop photons don't literally slow down or stop the photon. They store the information that describes the photon, destroy the photon, and create an exact replica of the photon. One experiment managed to stop the beam at a single point in space, and hold the information in a crystal for a few fractions of a second, and then release the exact copy. So they essentially (but not literally) stopped the photon. I can probably find the article in a solid state physics journal and post it for you if I can't find the news article.
    Here's an analogy to add that might make more sense. Imagine if I stepped into a teleporter device, and every bit of matter in my body was suddenly teleported to the moon. Then I was literally teleported.

    Now imagine if they completely destroy the matter that makes up my body, keep the information, and rebuild an exact replica of me on the moon. This replica is made of the same amount and configuration of protons, neutrons, electrons, neurons, blood vessels, consciousness, and anything else you can even think of applying to a human. They do this by using matter that's already on the moon though while my original body was destroyed. So essentially, it's me on the moon. Then they did effectively teleport me to the moon, but they didn't literally teleport my matter to the moon - they destroyed me and recreated me. It may seem trivial, but it's important in the case with light because at no point in time is there a photon traveling at less than the speed of light.

  7. #47
    Tottenham 'til I die
    Join Date
    Jan 2008
    Posts
    2,216
    BG Level
    7

    Quote Originally Posted by Woozie View Post
    Here's an analogy to add that might make more sense. Imagine if I stepped into a teleporter device, and every bit of matter in my body was suddenly teleported to the moon. Then I was literally teleported.

    Now imagine if they completely destroy the matter that makes up my body, keep the information, and rebuild an exact replica of me on the moon. This replica is made of the same amount and configuration of protons, neutrons, electrons, neurons, blood vessels, consciousness, and anything else you can even think of applying to a human. They do this by using matter that's already on the moon though while my original body was destroyed. So essentially, it's me on the moon. Then they did effectively teleport me to the moon, but they didn't literally teleport my matter to the moon. It may seem trivial, but it's important in the case with light because at no point in time is there a photon traveling at less than the speed of light.
    I think Heisenberg would like to have a word with you!

  8. #48
    Title: "HUBBLE GOTCHU!" (without the quotes, of course [and without "(without the quotes, of course)", of course], etc)
    Join Date
    Jul 2006
    Posts
    3,142
    BG Level
    7

    Quote Originally Posted by zoobernut View Post
    Thanks for clarifying that. It sounds like that is very similar to the experiment where they "teleported" the photon. In that experiment they essentially took in the information of the original photon in and then produced an exact replica in a different spot.
    lol, I spend all that time typing up an analogy, and you explain in one sentence what took me an entire paragraph to explain.

    I have a tendency to make my explanations longer and more drawn out than necessary (and in this case it seems no explanation was necessary, you already knew it and understood it perfectly well).

  9. #49
    blax n gunz
    Join Date
    May 2005
    Posts
    11,165
    BG Level
    9

    Quote Originally Posted by Woozie View Post
    For example, the shortest way to get from the north pole to the south pole on a sphere is traveling directly south with no deviations. Of course, when you're at the north pole, every direction is south, so you would have to pick a direction, and travel that direction along the sphere. But since a sphere is curved, you're not actually traveling in a straight line. So the shortest distance between two points (a geodesic) is not a straight line in this form of geometry.
    Reminds me of an old geek joke I heard back in college:

    A racehorse owner hires a biologist, a chemist, and a physicist to
    improve the performance of his stock. Months later, he returns.

    First the chemist says, "I have devised a new, undetectable drug that
    will improve the acceleration of your horses by 20%, admittedly while
    decreasing their lifespan by approximately the same amount."

    The biologist says, "I can't help you at the moment, but I have
    devised a selective breeding program which should ensure that you have
    a stable full of winners to pass on to your children."

    The physicist turns around from his blackboard, raises one finger, and
    says, "Consider a spherical horse..."

  10. #50
    The Mizzle Fizzle of Nikkei's Haremizzle

    Join Date
    Feb 2006
    Posts
    22,077
    BG Level
    10
    FFXI Server
    Bismarck

    Quote Originally Posted by Woozie View Post
    You know who's missing from this list? Neo and Kaylia. I just noticed that Neo doesn't post much in these kind of threads despite the fact that he probably knows more about this than any of us. And where has Kaylia been?
    Yeah Kaylia has been MIA for a minute, I was going to add him to my list then I remembered that he hadn't been on in forever.

    Quote Originally Posted by oldoldman View Post
    Have you ever read his books? He just piles speculation on top of speculation. I guess I should put the disclaimer that I'm a third year physics student and I absolutely despise string theory, which is what he bases his speculations on.

    Actually I have, all of them in fact. Even met him and listened to Dr. Kaku, Lee Smolin and the astounding Nathan Seiberg lecture in person when I was college, hence why I asked for a specific example.


    Quote Originally Posted by Woozie View Post
    lol, I spend all that time typing up an analogy, and you explain in one sentence what took me an entire paragraph to explain.

    I have a tendency to make my explanations longer and more drawn out than necessary
    I do the same thing lol, I usually will type something and think of a better analogy and have to go back and edit something I said. I usually do this about 5 or 6 times per post. You and I have talked about this before but my mind once it gets rolling is like a run away train which often leads to me having a bad inability to sleep lol.

  11. #51
    The Mizzle Fizzle of Nikkei's Haremizzle

    Join Date
    Feb 2006
    Posts
    22,077
    BG Level
    10
    FFXI Server
    Bismarck

    Quote Originally Posted by Correction View Post
    Reminds me of an old geek joke I heard back in college:
    lol that's awesome.

    Woozie do you still have that physicists and scientists joke you showed me like a year ago? Its the one where scientists went to a part and it went through each scientist one by one? You posted it for you LS and totally whooshed all of them, oh man that was great. I have it saved but im not at home atm.

    If he finds it, Epic-ness shall ensue.

  12. #52
    Renegade Philosopher
    Join Date
    Jul 2004
    Posts
    4,166
    BG Level
    7

    Hey guys I heard there was some physics going on in this thread. And you left me off the list

  13. #53
    The Mizzle Fizzle of Nikkei's Haremizzle

    Join Date
    Feb 2006
    Posts
    22,077
    BG Level
    10
    FFXI Server
    Bismarck

    Welcome! I cant say I recognize you though, poast moar. It's always a blast meeting someone with the same interests.

    We operate on the DL and function alot like fight club... just with 80% more postulates and theorem.

  14. #54
    Title: "HUBBLE GOTCHU!" (without the quotes, of course [and without "(without the quotes, of course)", of course], etc)
    Join Date
    Jul 2006
    Posts
    3,142
    BG Level
    7

    Quote Originally Posted by Mizango View Post
    lol that's awesome.

    Woozie do you still have that physicists and scientists joke you showed me like a year ago? Its the one where scientists went to a part and it went through each scientist one by one? You posted it for you LS and totally whooshed all of them, oh man that was great. I have it saved but im not at home atm.

    If he finds it, Epic-ness shall ensue.
    A Party of Famous Physicists

    One day, all of the world's famous physicists decided to get together for a tea luncheon. Fortunately, the doorman was a grad student, and able to observe some of the guests...

    * Everyone gravitated toward Newton, but he just kept moving around at a constant velocity and showed no reaction.
    * Einstein thought it was a relatively good time.
    * Coulomb got a real charge out of the whole thing.
    * Cavendish wasn't invited, but he had the balls to show up anyway.
    * Cauchy, being the only mathematician there, still managed to integrate well with everyone.
    * Thompson enjoyed the plum pudding.
    * Pauli came late, but was mostly excluded from things, so he split.
    * Pascal was under too much pressure to enjoy himself.
    * Ohm spent most of the time resisting Ampere's opinions on current events.
    * Hamilton went to the buffet tables exactly once.
    * Volt thought the social had a lot of potential.
    * Hilbert was pretty spaced out for most of it.
    * Heisenberg may or may not have been there.
    * The Curies were there and just glowed the whole time.
    * van der Waals forced himeself to mingle.
    * Wien radiated a colourful personality.
    * Millikan dropped his Italian oil dressing.
    * de Broglie mostly just stood in the corner and waved.
    * Hollerith liked the hole idea.
    * Stefan and Boltzman got into some hot debates.
    * Everyone was attracted to Tesla's magnetic personality.
    * Compton was a little scatter-brained at times.
    * Bohr ate too much and got atomic ache.
    * Watt turned out to be a powerful speaker.
    * Hertz went back to the buffet table several times a minute.
    * Faraday had quite a capacity for food.
    * Oppenheimer got bombed.
    Why God Never Received Tenure at any University

    # He had only one major publication.

    # It was in Hebrew.

    # It had no references.

    # It wasn't published in a refereed journal.

    # Some even doubt he wrote it himself.

    # It may be true that he created the world, but what has he done since then?

    # His cooperative efforts have been quite limited.

    # The scientific community has had a hard time replicating his results.

    # He never applied to the Ethics Board for permission to use human subjects.

    # When one experiment went awry he tried to cover it up by drowning the subjects.

    # When subjects didn't behave as predicted, he deleted them from the sample .

    # He rarely came to class, just told students to read the Book.

    # Some say he had his son teach the class.

    # He expelled his first two students for learning.

    # Although there were only ten requirements, most students failed his tests.

    # His office hours were infrequent and usually held on a mountaintop.
    DC Physics Humor

  15. #55
    Relic Horn
    Join Date
    Jun 2007
    Posts
    3,412
    BG Level
    7
    FFXI Server
    Odin
    WoW Realm
    Lightbringer

    Sort of late, but isn't the measurement of the constant speed of light 'c' supposed to be in a vacuum?

  16. #56
    Renegade Philosopher
    Join Date
    Jul 2004
    Posts
    4,166
    BG Level
    7

    Just to warn you I'm in the camp that believes that string theory might turn out to be one of the biggest wastes of effort in physics history. But I do lattice QCD so the LHC is still relevant to my interests. I'm guessing there hasn't been much progress on a new lepton collider though, what with the whole global economy being in the shitter.

  17. #57
    Insert Witty Title Here
    Join Date
    Jun 2006
    Posts
    6,383
    BG Level
    8

    Quote Originally Posted by Woozie View Post
    lol, I spend all that time typing up an analogy, and you explain in one sentence what took me an entire paragraph to explain.

    I have a tendency to make my explanations longer and more drawn out than necessary (and in this case it seems no explanation was necessary, you already knew it and understood it perfectly well).
    Thanks that is mostly a function of typing stuff out on the forums. In real life I am much more long winded and eloquent. I do what you do just in person.

  18. #58

    Quote Originally Posted by archibaldcrane View Post
    I never understood - if the speed of light is constant, then how can it be bent by gravity? If it's bent by gravity...doesn't that mean it can be accelerated or decelerated by gravity? Doesn't the existence of a black hole mean that light doesn't have a constant speed?
    Woozie explained it already, although I dont like the "takes shortest point from A to B" analogy, but it isnt light that is bending, it is the geometry of space that is being warped (theoretically). The simplistic way to think about it is to think of a stream of water that bends, a more complex way to think of it is examine the physical spatial area between the particles as you move farther away, integrating from 0 velocity to c (changing your relative frame) for each step you take. You begin to see the 3d spatial geometry change. It is postulated that this bending of space onto of itself (which is possible due to space being "empty") is what allows a blackhole to suck in so much matter and then spit it back out in the same direction (causing immense friction and the hottest temperatures in the universe at this singular point where in and out matter intersect). There are alot of physicist working on the dynamics of blackhole jets right now, it is pretty interesting stuff.

    But like I said, there really isnt "faster than light", because once you reach the speed of light, time/distance go to zero, and you are at your destination.

    One of the things that has been killing me however, is that I was constructing a 3d model of space/time and trying to expand a single point relatively as you decrease velocity from c, however it immediately breaks down. BUT! It does work if you expand it into a single x dimension, then y, then z. It kinda follows a vector behavior (which makes since, as when you move to the speed of light you arive at your destination instantly, relative to yourself, and dont arrive -everywhere- else (which would be the case if space did really contract on you equall in every dimension as you accelerated). It is just a really tedious and mind boggling problem. It is odd to me, that there is length dialation on an object traveling near c, but not width so to speak. It is as if the relative deconstruction occurs in one dimension at at time, and the other 2 dimensions are just subsets.

  19. #59
    Tottenham 'til I die
    Join Date
    Jan 2008
    Posts
    2,216
    BG Level
    7

    Quote Originally Posted by Seraph View Post
    Sort of late, but isn't the measurement of the constant speed of light 'c' supposed to be in a vacuum?
    Yes, that's the ideal medium. It's actually pretty easy to explain, light can only travel at it's constant velocity c, however when traveling through a medium such as water we perceive that light has slowed due to the observable refraction. What is actually happening is the photons are being absorbed by the atoms of the water molecule and then subsequently new identical photons are being emitted. While the speed the light travels remains constant the amount of time it takes to reach it's destination will be increased due to the delay between the atom absorbing a photon and the atom emitting an identical one.

    I'm not sure if I explained that well, I didn't sleep last night

  20. #60
    Ridill
    Join Date
    Dec 2006
    Posts
    9,740
    BG Level
    8
    FFXI Server
    Asura

    It got ED

Similar Threads

  1. Two Nuclear Submarines Collide in Atlantic Ocean
    By Firedemon in forum General Discussion
    Replies: 33
    Last Post: 2009-02-18, 05:38
  2. The Large Hadron Collider goes online tonight...
    By alt in forum General Discussion
    Replies: 8
    Last Post: 2008-09-10, 00:50
  3. Large Hadron Collider...
    By Jotaru in forum General Discussion
    Replies: 71
    Last Post: 2007-11-05, 21:42