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Double-Slit Experiment in Time, Not Space

Posted by timothy on from the that-young-guy-did-a-bunch-of-stuff dept.

TheMatt writes "Thomas Young's double-slit experiment is a classic experiment that helped establish the wave-like nature of light. Since then, it has been done with atoms, buckyballs, and biomolecules. It has even been seen in a single molecule, and the single electron version was voted the most beautiful experiment by Physics World readers (covered previously on Slashdot). Now, PhysicsWeb is reporting that Gerhard Paulus and coworkers have conducted the double-slit experiment using a double-slit in time, not space. The "slit" was a crafted femtosecond pulse consisting of one-and-a-half cycles--say, two maxima and one minima--passed through an argon gas. Each maxima has a probability of ionizing an argon atom and producing an electron. The electrons were accelerated to a detector which observed an interference pattern since the detector had no idea which maximum produced the electron."

7 of 535 comments (clear)

  1. Re:Ah yes... by Anonymous Coward · · Score: -1, Troll

    Tis a pitty your nanosized brain can't grasp anything better to say.
    -nB

  2. Can I just be the first to say... by cliveholloway · · Score: 1, Troll

    ...that this has to be the most confusing summary ever. Here's my guess on timothy's brain processes.

    double-slit ... wave-like ... femtosecond ... maxima ... minima ... interference pattern ... Oooo shiny (click's approve).

    Or am I the only one who knows absolutely nothing about this subject or the significance of the experiment?

    How about some *editing* timothy?

    cLive ;-)

    --
    -- Trinity in high heels carrying a whip: The donimatrix - there is no spoonerism
    1. Re:Can I just be the first to say... by Qzukk · · Score: 0, Troll

      YHBOG

      ------------------------
      You Have Been Out-Geeked
      ------------------------

      That's right, you have been Out-Geeked. A story was posted that far surpasses your mental capacity for geekiness, and now you find yourself confounded and confused. Google is of little help, explaining terms like "femtosecond" in terms of seconds and "maxima" in terms of those number-thingies you keep telling yourself you need to learn to count. Wikipedia is of even less help since the Interference Pattern entry has been replaced (again) by the GNAA stating that they will interfere with wikipedia as well as links to rather disgusting pictures.

      What is someone like you to do?

      Well, for one you can go back to school. Complete an engineering, physics, or mathematics undergraduate degree, these are suitably geeky enough to provide you with a solid grounding in all things geeky. If you have already completed such a degree and have yet to discover that inner geek you know is hiding in there, a Ph.D. in any of those subjects will be sure to call it out. Once you have gotten comfortable with your geeky side, you will find that such terms as "wave-like" no longer faze you.

      Alternatively, you can attend user groups or lectures that are attended by those geekier than you. Is a Ph.D. going to give a speech in your area about the effects of left-handed polyisobritonan radiation on psihibrionic mesh wedges? Take 3 or 4 hours of your day to attend the lecture. Rub elbows with those geekier than you, and be sure to watch over their shoulders at the notes the people in front of you are taking. User groups are particularly a good choice, while these groups typically focus on a software application or operating system, their true purpose is for the truly geeky to pass on their geekiness to those below them in the ranks. After a dozen or so meetings or lectures, you should find your geek quotient rising, as well as your capacity to further your own geekiness.

      --
      If I have been able to see further than others, it is because I bought a pair of binoculars.
  3. Re:Great minds think alike. : Moving Dimensions by RangerWest · · Score: -1, Troll
    What about it doesn't make sense to you? It's a new way of thinking. It makes sense to me:

    Dr. Elliot says:

    The only way to stay still in the three spatial dimensions is to move at the velocity of light c through time. The only way to stay still in the time dimension is to move at the velocity of light c through space. How else can this be explained, but with space and time coordinates are in motion relative to one-another?

    I propose that the time dimension is moving relative to the three spatial dimensions. Such a concept may be used to explain physical phenomena found in relativity and quantum mechanics. The constant speed of light, time dilation, Lorentzian contraction, wave-particle duality, the equivalence of mass and energy, the gravitational red-shift, and the second law of thermodynamics may all be explained on a deeper level by a theory of moving dimensions. Such a theory may also offer a path for the unification of Quantum Mechanics and Relativity.

    The only way to stay still in the three spatial dimensions is to move at the velocity of light c through time. The only way to stay still in the time dimension is to move at the velocity of light c through space. How else can this be explained, but with space and time coordinates are in motion relative to one-another?

    The four dimensions of space-time are divided into three spatial dimensions and one time dimension. In the space-time metric, where ds is an invariant expressed as ds^2=x^2+y^2+z^2-c^2t^2, the minus sign and c^2 distinguishes the t coordinate from the three spatial coordinates. Why the minus sign exists is most often glossed over.it is considered to just "be" there, because it is there.

    This paper explains the -c^2 in front of the t coordinate by proposing that the time dimension, the actual coordinate system, is moving relative to the three spatial dimensions. The time dimension is expanding at a rate of c relative to the three spatial dimensions, in a spherically symmetric manner.

    Many trained physicists have a knee-jerk reaction that the time dimension cannot be moving because .dimensions cannot move.. First off, since the universe is expanding, space-time is also expanding, demonstrating that dimensions are moving and expanding. Secondly, general relativity demonstrates that massive objects warp space-time, meaning that as a massive object moves though space-time, it stretches space-time, showing again that space-time in one area can move, or deform, relative to space-time in another area. Thus there exist neither philosophical nor physical barriers to the concept of moving dimensions, but for artificial ones within lazy minds.

    Rather than just accepting the minus sign in front of the c^2t^2 as being there because it .just is there,. this paper aims to look at the deeper reality which gives rise to the minus sign. A physicist.s job is not to accept things on blind faith, nor only ask questions that are allowed to be asked, but a physicist.s job is to wonder. And that wonder, which seems all but forgotten in the bureaucratization of modern physics, leads to the deeper beauty. Imagination is more important than knowledge, was how one physicist put it.

    That the time dimension is different somehow from the three spatial dimensions is obvious. This difference is a result of the time dimension moving relative to the spatial dimensions.

    Picture four dimensions.three spatial dimensions and one time dimension. An object can be rotated so that its projection along any particular axis decreases. When an object is rotated into time, its projection along the x, y, and z directions decreases. This is known as relativistic length contraction. Relativistic length contraction is *always* accompanied by time dilation and an increase in the object's velocity.

    It is not possible to conduct a Lorentz transformation on a ruler, where it is rotated into the time dimension, without the ruler gaining a velocity through the

  4. Re:Physics Explained! by Serveert · · Score: -1, Troll

    everybody and their mother has a unification theory now and they're willing to take your money before explaining it.

    --
    2 years and no mod points. Join reddit. Because openness is good.
  5. Re:Hrm by Anonymous Coward · · Score: -1, Troll

    There is no God

    Um, yes there is.

    ---
    Score: -1, Troll

  6. Perhaps a little easier on the eyes by uberdave · · Score: -1, Troll

    This experiment supports Dr. Elliot's theory of moving dimensions:
    Link1
    Link2

    The four-dimensions of space-time are divided into three spatial dimensions and one time dimension. In the space-time metric, s^2=x^2+y^2+z^2-c^2t^2, the minus sign and c^2 distinguishes t from the three spatial dimensions. Why the minus sign exists is most often glossed over--it is considered to just "be" there. This paper explains the minus sign by proposing that the time dimension, the actual coordinate system, is moving relative to the three spatial dimensions.

    The time dimension is expanding at a rate of c relative to the three spatial dimensions, in a spherically symmetric manner. Many trained physicists have a knee-jerk reaction that the time dimension cannot be moving because "dimensions cannot move." First off, since the universe is expanding, space-time is also expanding, showing that dimensions are moving and expanding. Secondly, general relativity demonstrates that massive objects warp space-time, meaning that as a massive object moves though space-time, it stretches space-time, showing again that space-time in one area can move, or deform, relative to space-time in another area.

    Rather than just accepting the minus sign in front of the c^2t^2 as being there because it just is there, this paper aims to look at the deeper reality which gives rise to the minus sign. A physicist's job is not to accept things on blind faith, nor only ask questions that are allowed to be asked, but a physicist's job is to wonder. And that wonder, which seems all but forgotten in the bureaucratization of modern physics, leads to a deeper beauty.

    That the time dimension is different somehow from the three spatial dimensions is obvious. This difference is a result of the time dimension moving relative to the spatial dimensions. Picture four dimensions--three spatial dimensions and one time dimension. An object can be rotated so that its projection along any particular axis decreases. When an object is rotated into time, its projection along the x, y, and z directions decreases. This is known as relativistic length contraction. Relativistic length contraction is *always* accompanied by time dilation and an increase in the object's velocity. It is not possible to conduct a Lorentz transformation on a ruler, where it is rotated into the time dimension, without the ruler gaining a velocity through the three spatial dimensions. Because rotating an object into the time dimension always results in the object gaining a velocity relative to the spatial dimensions, one can conclude that the time dimension must be moving.

    Einstein's two postulates of relativity state: I. The laws of physical phenomena are the same in all inertial frames. II. The velocity of light in free space is a universal constant, independent of any relative motion of the source and the observer. I propose that the two postulates may be expressed in an alternative manner, by stating the following law of moving dimensions: I. The time dimension is moving relative to the three spatial dimensions.

    This can be shown illustrated in several ways: Consider an expression for the space-time interval of zero length, or of the null vector, which traces a photon's path through space-time: x^2+y^2+z^2-c^2t^2=0 or x^2+y^2+z^2=c^2t^2 which for one spatial dimension becomes x^2=c^2t^2 or x=ct. By taking the derivative of both sides with respect to t, we get dx/dt = d/dt (ct) = c, so dx/dt = c. And hence the time rate of change of the spatial dimension relative to the time rate of change of the time dimension is equal to the velocity of light. ct | / | / | / | / | / |/_______________ x

    Also, if we trace the path of a photon on a space-time diagram, the only way for a photon to remain stationary in space-time is to move at the speed of light, or to keep up with the expanding time dimension. The null vector, which rep

    --
    "I'm not impatient. I just hate waiting." - My Dad