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Quantum Physics - This will blow your mind

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Comments

  • Registered Users, Registered Users 2 Posts: 8,488 ✭✭✭Goodshape


    Groovy. Like the story of Schrodinger's Cat :)


  • Registered Users, Registered Users 2 Posts: 23,216 ✭✭✭✭monkeyfudge


    That does a really good job of explaining it actually.

    This principle was recenlty used to create quantum clones of a photon. Of course each clone is slighly different because of the uncertainty principle so your end result is like the two different captain kirks after the teleportation accident in that episode of Star Trek.


  • Registered Users, Registered Users 2 Posts: 7,481 ✭✭✭Blisterman


    I don't understand it? How can observing it, cause it to not create the interference pattern?


  • Registered Users, Registered Users 2 Posts: 23,216 ✭✭✭✭monkeyfudge


    Blisterman wrote:
    I don't understand it? How can observing it, cause it to not create the interference pattern?
    Well.. untill it is observed it is pure potential and goes though both slots and neither slots all at the same time.

    The act of observing actualises an event and it will go through one or the other slot.

    This principle can also be applied to concept of quantum computers where the state of the computer can be both a 1 and 0 at the same time.


  • Registered Users, Registered Users 2 Posts: 7,481 ✭✭✭Blisterman


    :confused:


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  • Registered Users, Registered Users 2 Posts: 8,488 ✭✭✭Goodshape


    Blisterman wrote:
    :confused:
    I think that's the point. It doesn't make much sense based on the way we commonly understand things. Non the less, it happens.

    Turns out we haven't got it all figured out after all... who'd a thunk?


  • Registered Users, Registered Users 2 Posts: 23,216 ✭✭✭✭monkeyfudge


    I always love that episode of Futurama where they are at the races and it's a quantum finish and they take a photo to determine who the winner was.

    And Farnsworth shouts:
    "No fair! You changed the outcome by measuring it!"


  • Closed Accounts Posts: 11,909 ✭✭✭✭Wertz


    I need a drink.


  • Closed Accounts Posts: 213 ✭✭BigWilly


    Well.. untill it is observed it is pure potential and goes though both slots and neither slots all at the same time.

    The act of observing actualises an event and it will go through one or the other slot.

    This principle can also be applied to concept of quantum computers where the state of the computer can be both a 1 and 0 at the same time.


    That is freaky. And I don't understand how that could happen at all...


  • Closed Accounts Posts: 213 ✭✭BigWilly


    Wertz wrote:
    I need a drink.


    :)


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  • Closed Accounts Posts: 292 ✭✭Sgt. Politeness


    wow...intermolesting


  • Closed Accounts Posts: 3,494 ✭✭✭ronbyrne2005


    well strange indeed.arent electrons in orbit in atoms in many places at once?and you can either measure its direction or location but neither at same time?
    i find sub atomic physics baffling but amazing.
    so how is the measuring affecting the electron? whats the theories?


  • Closed Accounts Posts: 11,909 ✭✭✭✭Wertz


    I often had it explained to me that the measures used to observe happenings at the quantum level effect what it is you're trying to measure. The very act of the particle emitting something that can then be detected (and hence it's detection if equipment is present) is enough to feedback onto the particle and change it's vector/state.


  • Closed Accounts Posts: 3,494 ✭✭✭ronbyrne2005


    Wertz wrote:
    I often had it explained to me that the measures used to observe happenings at the quantum level effect what it is you're trying to measure. The very act of the particle emitting something that can then be detected (and hence it's detection if equipment is present) is enough to feedback onto the particle and change it's vector/state.
    can they not use sensors that dont emmit anything but detect electrons hitting the sensors surface?


  • Closed Accounts Posts: 3,643 ✭✭✭magpie


    Mroy


  • Closed Accounts Posts: 11,909 ✭✭✭✭Wertz


    can they not use sensors that dont emmit anything but detect electrons hitting the sensors surface?

    Well usually to detect the event you have to use some form of electromagnetic opposing force, I think.

    I'm not even talking about the detection equipment emmiting anything....just the very act of the particle making itself detectable (and that emmision being subsequently detected) is enough to influence it's state.

    ...and bear in mind this is an the electron level; something that isn't that hard to detect....when you get into the realms of the real sub atomic particles, things get a whole hell of a lot more f*cked up.


  • Moderators, Society & Culture Moderators Posts: 9,689 Mod ✭✭✭✭stevenmu


    can they not use sensors that dont emmit anything but detect electrons hitting the sensors surface?
    Hitting the sensors surface would kind of interfere with the electrons though ;)


  • Closed Accounts Posts: 7,352 ✭✭✭funky penguin


    It's like putting too much air in a balloon!


  • Closed Accounts Posts: 9,082 ✭✭✭lostexpectation


    Well.. untill it is observed it is pure potential and goes though both slots and neither slots all at the same time.

    The act of observing actualises an event and it will go through one or the other slot.

    This principle can also be applied to concept of quantum computers where the state of the computer can be both a 1 and 0 at the same time.


    how does it change from an electron to potential electron?


  • Registered Users, Registered Users 2 Posts: 21,264 ✭✭✭✭Hobbes


    how does it change from an electron to potential electron?

    It can exist as a particle or a wave.

    Think of it this way, tie a string to a ball and spin around really fast. If you spin it fast enough it will look like a circle. This is it in wave form. If it was an electron it would exist at every point in that circle. However once you try to determine its location it may or may not be in the spot you observe at a given time.

    Or something like that.


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  • Registered Users, Registered Users 2 Posts: 9,480 ✭✭✭projectmayhem


    Well.. untill it is observed it is pure potential and goes though both slots and neither slots all at the same time.

    The act of observing actualises an event and it will go through one or the other slot.

    do you mean that it depends on the person performing the experiment/viewing it? i.e. can two different observers come to different conclusions on the same experiment, or can it be proven that the electrons went through slot a or b? i don't know much about physics, not least quantum physics.

    great vid btw


  • Registered Users, Registered Users 2 Posts: 7,481 ✭✭✭Blisterman


    I have some to the conclusion that quantum physics is too complicated to bother trying to understand.


  • Closed Accounts Posts: 503 ✭✭✭OMcGovern


    Hobbes wrote:
    It can exist as a particle or a wave.

    Think of it this way, tie a string to a ball and spin around really fast. If you spin it fast enough it will look like a circle. This is it in wave form. If it was an electron it would exist at every point in that circle. However once you try to determine its location it may or may not be in the spot you observe at a given time.

    Or something like that.

    Must be a new version of "string theory" I haven't read about yet :)


  • Closed Accounts Posts: 6,706 ✭✭✭Voodu Child


    The most baffling thing is theyre teaching this stuff to kids these days (well, i presume they are, given the presentation of the cartoon).

    In my day, talk of electricity and such would have you burned alive at the stake...


  • Closed Accounts Posts: 698 ✭✭✭meldrew


    That went totally over my head


  • Registered Users, Registered Users 2 Posts: 5,618 ✭✭✭Civilian_Target


    Wertz wrote:
    I need a drink.

    Oh how I long for a drink, alcoholic of course, after the heavy lectures involving Quantum Mechanics. - Asimov


  • Registered Users, Registered Users 2 Posts: 4,559 ✭✭✭The tax man


    Hmmm....Electrons seem to act similar to people in a way.
    Neither like to interfere with themselves when someone is watching.:D


  • Closed Accounts Posts: 2,025 ✭✭✭slipss


    Blisterman wrote:
    I don't understand it? How can observing it, cause it to not create the interference pattern?

    basically observing a parical changes it because to observe it you have to shine light on it, and light is a form of energy/matter. Wasn't this figured out about the same time the question was asked?


  • Registered Users, Registered Users 2 Posts: 3,354 ✭✭✭radiospan


    So this weirdness happens for small things like electrons, but not for big things like marbles.

    Is there some kind of threshold size, below which this weirdness happens?

    I read "In Search of Schrodinger's Cat", but I can't remember if it mentioned this or not.


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  • Registered Users, Registered Users 2 Posts: 6,374 ✭✭✭Gone West


    I prefered schroedinger's cat analogy.


  • Registered Users, Registered Users 2 Posts: 4,780 ✭✭✭JohnK


    Hmmm....Electrons seem to act similar to people in a way.
    Neither like to interfere with themselves when someone is watching.:D
    Brilliant :D


  • Registered Users, Registered Users 2 Posts: 5,523 ✭✭✭ApeXaviour


    plazzTT wrote:
    So this weirdness happens for small things like electrons, but not for big things like marbles.

    Is there some kind of threshold size, below which this weirdness happens?

    I read "In Search of Schrodinger's Cat", but I can't remember if it mentioned this or not.
    Yeah.. well not a threshold per se, a little more gradual than that. It's to do with particle wave duality. All particles act like a wave, it just doesn't become really apparent until you get to really small masses. The wavelength of a particle is given by the de-broglie wavelength L=h/mv. Where h is plancks constant (a really really really small number), m is mass and v is velocity. So you can see from that, if m is big (say for a football), L is gonna be really small. But the smaller m becomes the bigger the wavelength and the more its behaviour can be described by a wave.

    And when you try to describe a particle that's acting like a wave (is a wave?), that's when the "weirdness" comes in, or as we like to call it: the Uncertainty Principal*. ;)


    *A wave doesn't have a definite position so where is the particle? Just measure it. Ok now it's got a definite position but now how fast is it going? We don't know. Why? Cos the "wave" is so short now there aren't enough oscillations to measure its speed accurately. Dammit!


  • Registered Users, Registered Users 2 Posts: 15,620 ✭✭✭✭Supercell


    stevenmu wrote:
    Hitting the sensors surface would kind of interfere with the electrons though ;)

    Thats the only conclusion that makes sense to me. To measure something you must interact with it somehow, I wonder if future measurement techniques will become as benign as for example the human eye looking at a something and if the interference pattern resumes at that point.

    Have a weather station?, why not join the Ireland Weather Network - http://irelandweather.eu/



  • Registered Users, Registered Users 2 Posts: 6,374 ✭✭✭Gone West


    ApeXaviour wrote:
    *A wave doesn't have a definite position so where is the particle? Just measure it. Ok now it's got a definite position but now how fast is it going? We don't know. Why? Cos the "wave" is so short now there aren't enough oscillations to measure its speed accurately. Dammit!
    *sniff*
    Is that you mr. Heisenberg?


  • Closed Accounts Posts: 978 ✭✭✭bounty


    Pretty damm mind boggling cool


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  • Registered Users, Registered Users 2 Posts: 436 ✭✭mossieh


    It's like putting too much air in a balloon!

    sweet...:)


  • Registered Users, Registered Users 2 Posts: 27,644 ✭✭✭✭nesf


    My favourite way of putting it is that Plank's Constant is almost zero. :)


    There is a Physics forum you know guys.... ;)


  • Registered Users, Registered Users 2 Posts: 8,067 ✭✭✭L31mr0d


    yeah that is exactly what i was wondering, what is this doing in the after hours forum? I came in here looking to catch up on the best kebab shop in dublin thread only to see this sitting here, interesting, but out of place.

    Quantum physics? Isn't that what sent Dr. Sam Beckett solving peoples problems at different points in time with the help of his trusty sidekick, Al the hologram?

    It is very interesting but not that hard to fathom, i don't see what all the ruckus is about. If they ever manage to crack its use in engineering and mechanics, computers will have powers that at the moment only resides in science fiction, this is due to the wavelike property of particles, being all possibly states simultaneously. Which means that a 4-bit electronic computer would be a 32-bit Quantum computer (i.e. 2^4) as each bit would simultaneously be a 1 and a 0. Do the maths for modern day 64-bit computers.

    I think the animation only goes to over simplify the situation, saying things like "as if the particle knew it was being watched". Applying sentience to a particle will only confuse people. My favourite example is the photon sent down a path that splits in 2, each path with equal importance. Which path does the photon take. The answer, it takes both, even though it is impossible for a photon to split by itself, it appears in two places. The greatest thing about quantum physics for me is that it managed to stump einstein.

    Now whos up for discussing tachyons in relation to quantum mechanics, I hear this thread ends well if we do :D


  • Closed Accounts Posts: 15,914 ✭✭✭✭tbh


    so wait. The Chief KNEW internal affairs were setting him up??!!?


  • Registered Users, Registered Users 2 Posts: 1,256 ✭✭✭c0rk3r


    fúck science, load of shít.


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  • Registered Users, Registered Users 2 Posts: 35,522 ✭✭✭✭Gordon


    But weren't the scientists 'observing' the particles before they put a measuring device in place? Or were they protected by the walls of the ... erm... chamber thing?


  • Registered Users, Registered Users 2 Posts: 37,315 ✭✭✭✭the_syco


    Heh.Thats cool.

    OP, can you tell us who or what that dude/series is called? I'm intrested.


  • Registered Users, Registered Users 2 Posts: 6,374 ✭✭✭Gone West


    Nope, you see:

    You gotta calibrate the dialithium crystals to match the stargate's natural frequency of resonance. Then using a particle accelerator and the enterprise's photon torpedoes you can mac-guyver a quantum portal......


    etc.


  • Registered Users, Registered Users 2 Posts: 9,480 ✭✭✭projectmayhem


    FuzzyLogic wrote:
    Nope, you see:

    You gotta calibrate the dialithium crystals to match the stargate's natural frequency of resonance. Then using a particle accelerator and the enterprise's photon torpedoes you can mac-guyver a quantum portal......


    etc.

    ohhhh


  • Registered Users, Registered Users 2 Posts: 8,067 ✭✭✭L31mr0d


    Quantum Computing Technical Document

    A must read for anyone considering getting involved in this area.


  • Closed Accounts Posts: 463 ✭✭tunaman


    the_syco wrote:
    Heh.Thats cool.

    OP, can you tell us who or what that dude/series is called? I'm intrested.

    No idea, but the aim of this thread was to make people realise how little they really know about anything.

    Knowledge = power.


  • Closed Accounts Posts: 17,208 ✭✭✭✭aidan_walsh


    c0rk3r wrote:
    fúck science, load of shít.
    Because, amongst many many other things you use day to day, the box you used to type this wonderful observation is obviously powered by God, pixie dust and Harry Potter's arse gas.


  • Closed Accounts Posts: 17,208 ✭✭✭✭aidan_walsh


    the_syco wrote:
    Heh.Thats cool.

    OP, can you tell us who or what that dude/series is called? I'm intrested.
    Its from a DVD called What the Bleep? Down the Rabbit Hole.


  • Registered Users, Registered Users 2 Posts: 21,611 ✭✭✭✭Sam Vimes


    i'm not too sure about that. what did they use to measure it? it obviously wasn't an eye. a measuring device could change the outcome of the experiment. for example if you put an ammeter ( a current measuring device) in a circuit, it will itself draw some current, thus changing its value. so "observing" the experiment changes its outcome because the device used to measure it changes its behaviour. there's nothing magical about it


  • Registered Users, Registered Users 2 Posts: 17,371 ✭✭✭✭Zillah


    I love quantum physics. Did indeed explain it very well.


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