electron emitter details for double slit experiment

No, it's a perfect indication that it is correct, because quantum theory ==> matter waves (and in light's case, its wave function obeys Maxwell's laws, something you should be familiar with).

For being diametrically opposed to quantum theory, you sure don't know it very well, at all.

Tim

-- Deep Fryer: A very philosophical monk. Website @

How do you know which ones? ;-)

Tim

-- Deep Fryer: A very philosophical monk. Website @

I recall he also said, "no one understands quantum mechanics."

Tim

-- Deep Fryer: A very philosophical monk. Website @

Published in Physics Review Magazine by The American Physical Society DOI: 10.1103/PhysRevD.9.853 URL:

Title: Experimental distinction between the quantum and classical field-theoretic predictions for the photoelectric effect

Abstract: We have measured various coincidence rates between four photomultiplier tubes viewing cascade photons on opposite sides of dielectric beam splitters. This experimental configuration, we show, is sensitive to differences between the classical and quantum field-theoretic predictions for the photoelectric effect. The results, to a high degree of statistical accuracy, contradict the predictions by any classical or semiclassical theory in which the probability of photoemission is proportional to the classical intensity.

Not bad.

I don't think there is much actual evidence that the brain relies on quantum effects though. (I mean the "spooky" ones of which you speak - obviously quantum mechanics is the mechanism underlying e.g. chemistry).

And the "We're just a bag of chemicals" theory does seem to dispose of a lot of the "problems" in philosophy and religion.

I suspect anything macroscopic has a mass/momentum large enough to have a De Broglie wavelength small enough to approach the Planck length. At that level, if speculation holds, space-time is more like a boiling foam than anything stable enough to produce interference fringes.

This does a very nice job with these issues.

Robert H.

And so far there is no good reason to suppose that there has to be more than that. Although there are some tantalising hints that both the DNA code (4 bases) and the common amino acids (20) used in life are governed by quantum mechanical comparison rules. A single QM if statement branches 4 ways (not like our classical binary code), and 3 nested comparisons gets you to 20). I still wouldn't put it much higher than a conjecture at this stage, but it does tend to suggest that in a classical world life would be much harder to get started.

I prefer mechanistic or statistical probability explanations they have a lot more predictive power.

Actually you cannot prove that the photon does not take all the paths available to it. It behaves exactly as if it has explored all of them up to the point it arrives at the detector. Try to deprive it of the apparently "unused" paths and the interference pattern will change - or if you attempt to see which slit the photon went through.

In fact if you do the mathematics it is possible to show that all but the path(s) corresponding to the shortest time path integral between a point on the object and the detector will cancel out almost exactly. That hard line would be the classical geometrical optics result - the true point spread function being probabilistic with a shape dependent roughly on the Fourier transform of the aperture in most imaging setups.

I don't see that you need the brain to be a quantum computer. The immense numbers of connections and network complexity is probably enough to allow consciousness. Computer networks will be big enough to test this hypothesis within our liofetime if Moores law holds good. It is still interesting that the chemistry that underpins life itself was probably helped to get started by the rules of quantum mechanical computing.

I don't do magic as the explantion of anything. Any sufficiently advanced technology looks like magic.

Regards, Martin Brown

The flux *through* a SQUID may be quantized to units of h/2e Weber, but that doesn't keep it from being useful for measuring very much smaller amounts. Flux isn't by itself quantized; It's merely the response of the SQUID that is. In fact, the response of a SQUID is *periodic* as a function of flux with period h/2e. Nothing keeps you from resolving a fraction of a period.

Jeroen Belleman

Those short, little blue ones.

John

You can believe that electromagnetics are quantized without believing in photons as things. We have this discussion on sci.optics quite regularly. Here's a post of mine on this subject from three weeks ago, with a bunch of links to previous discussions. We have some pretty heavy hitters on that group, e.g. Profs Siegman and Ruff, so it's worth reading.

Cheers,

Phil Hobbs

Newsgroups: sci.optics From: Phil Hobbs Date: Tue, 25 Mar 2008 20:02:49 -0500 Local: Tues, Mar 25 2008 9:02 pm Subject: Re: Light Duality

Quantum Ray wrote: > We're all taught about the duality nature of light, that the light > wave is made of photons, which behave like particles.

It isn't correct to say that a light wave is 'made up of photons', at least not if you think of a photon as being a well-defined object, such as a brick or an electron.

Some previous threads on photons:

Earlier:

Cheers,

Phil Hobbs

Have you ever talked to one? Those guys are CRAZY!! You would be too, if you ever tried to repair a Quantum. ;-)

They work at the macro level, when lots of particles are involved and quantum effects can be approximated by averages. They don't work at the atomic level. DNA works at the atomic level.

Of course it explores all the paths, instantly, even if it has to reach out light-years in all directions to do it. Even though it is local and indivisible.

John

And have you seen the prices Sears is charging for a single Quantum Wrench? I don't know how anyone can afford to buy an entire Sears Craftsman Quantum Mechanic's Tool Set...

By how their light feels. :-)

Cheers! Rich

Hi,

"in which the probability of photoemission is proportional to the classical intensity"

To verify that the photoemission is not proportional to the classical intensity only shows that matters energy states are quantized. The energy that causes the photoemission can be continuous still in this case, but will only cause a photoemission in steps, which has been misinterpreted to mean that the light itself must be quantized.

cheers, Jamie

Hi,

It is only "undefined" because it hasn't been measured? Why can it not still be defined but unknown? If that was the case then there would be no need to imagine that information is travelling instantly from one "entangled photon" to the other light years away.

The quantum mechanics concept of light being only "probability waves" causes this information to need to travel instantaneously from one entangled particle to the other.

Quantization of a continuous system is a useful tool in many cases as quantum mechanics shows, but it is not reality, as can be seen from how it doesn't agree with known quantities, like the speed of light.

This seems to be quite a strange way to think to me. Isn't it more logical to think that the spins are opposite no matter what and are predefined? The whole problem is due to thinking in terms of probability waves, with that idea it is not possible to acknowledge the actual existence of these two opposite spins, and they can only come about once the measurement is made. Seems like nonsense to me.

I believe in consciousness and free will, and also believe in a medium that electromagnetic waves travel in (classical physics?). I think that either quantum or classical interpret ions of reality have room for all of these different viewpoints of consciousness.

I think classical physics can be magical as well, isn't the concept of an aether medium that connects us all interesting?

Very interesting, thanks for posting! :)

cheers, Jamie

Photons can have any energy, as they do in, say, the radiation emitted by a thermal source. But any one photon has a specific energy hence wavelength. That's not too startling. What's startling is that the photon isn't divided into two pieces by a beam splitter, but all of its energy takes one path or the other. Yet a single photon, given two possible paths, takes both paths and interferes with itself.

Of course quantum mechanics isn't logical.

Irony: four hundred years ago or so, the church declared that God created the mysteries of reality. Science proceeded to chip away those mysteries, one by one, until ca 1900 the scientists ruled and religion was in retreat. Religion shifted from "the celestial spheres prove the existance of God" to "God can be approached only through faith."

Then the scientists stumbed onto quantum mechanics. Qm is irrational, illogical, non-causal, completely in contradiction to how people view reality. The only way to deal with quantum mechanics is through faith.

John

Yes thats correct, using matter as a measurement tool I don't see any way to verify whether light is inherently quantized.

However it is easy to prove that light is not quantized just by assuming it is :) Just look at the results of this assumption, ie. the nonsense results like spooky action at a distance.

The field can't be quantized unless you are willing to deny the speed of light. I ask you why assume that the field is quantized? What is the benefit of this?

cheers, Jamie

Why do you need faith to deal with a theory that is supported by experimental evidence? And since when is adjusting how reality is viewed too much to ask? Anyway, the inescapable fact is that existence itself _is_ a mystery, and always will be. The part can't understand the whole, the tiny part less so. Making up "just so" stories about god to explain creation is a sacrilege against the unfathomable mystery of existence. Looking to quantum mechanics to explain the operation of mind is underestimating the marvels of the emergent properties of complex systems. Or it may also be the result of looking for another excuse to continue believing in religion. If you really need magic, just try to figure out existence. If a god jumps into the way, try to figure out its existence.