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I look at life with detachment and distance, like a window shopper. Not only I study the window but also my own reflections in it.

A Ghost Could Be Anywhere If You Aren't Looking

Thursday, April 14, 2005 2 comments

What happens between the two instances of time quanta? Jaspal's comment on my last post is interesting.
I had hinted in earlier posts, at the dilemma of measurement of length and Time. When we measure something, we interfere with its state, and change it, by the very process of measurement. This is more true of quanta-sized measurements. We can measure the position of a photon, by shooting electrons (or even photons), at it and measuring the ricocheting electron. We measure photon's position but alter its momentum by giving it a mighty push. This trade-off between uncertainty of measurement of position vis-a-vis momentum, is written as a equation and is called Heisenberg uncertainty Principle. This means that we can never know exact position and momentum of a particle.
A Ghost could be anywhere if you aren't looking.
When you are not looking for the position of the Photon, it could as well be, anywhere in the world. As a result, no particle or quanta is a hard particle with sharp boundaries. There is an uncertain smudging of its boundaries. Like an object under light has a deep shadow (called Umbra) and a larger softer penumbra. This also leads to the wave/Particle duality of light. Light, looks like a wave phenomenon, untill you make it a point, to look for the position of the photon - when it seems to be like a particle.
In fact such soft penumbra like boundaries, of two particles may overlap, without creating a collision ( Pauli Exclusion principle is also involved - but lets forget that for the moment).
This is what happens between two instances of time quanta. They actually overlap. There is infact no timeless gap between the two instances of time quanta.

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2 comments: to “ A Ghost Could Be Anywhere If You Aren't Looking so far...

  • Mark Rezyka May 29, 2005 6:57 AM

    Sorry to burst your bubble on this Girish, but your argument that we must interfere with a particle’s momentum when measuring it’s position and vice versa is patently wrong. That is not at all what the uncertainty principle refers to. I don’t have time, or inclination to explain it all to you but remember this.

    We can often measure where a particle is by measuring where it is not.

    i.e. if we put a sensor on only one of the two slits in the famous two slit experiment, and send a single photon thru the slits, and if our sensor does not fire, we KNOW which slit the photon went through even though we have not interacted with it at all, at least from the point of view you seem to have embraced. But here is the rub. Even tough we have not interacted with it in any physical way; we cause it’s wave function to collapse and cause it to behave as a particle and no longer as a wave. This basic tenant is something you must understand completely, if you are ever to gain any real insight into the quantum world.

  • Girish November 06, 2005 5:28 PM

    Thanks Mark
    Yes I was off the Mark.
    Your way of explaining is quite good.
    But as we know all qualitative explaination being but an approx. of the mathematics of physics - is bound to be but an approximation.

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