Text Box: Does the photon actually split in two and travel partly through one slit and partly through the other? Most physicists would object to this way of phrasing things. They would insist that while the two routes open to the particle must both contribute to the final effect, these are just alternative routes, and the particle should not be thought of as splitting into two in order to get through the slits. As support for the view that the particle does not partly go through one slit and partly through the other, the modified situation may be considered in which a particle detector is placed at one of the slits or the other. Since when it is observed, a photon – or any other particle – always appears as a single whole and not as some fraction of a whole, it must be the case that our detector detects either a whole photon or no photon at all. However, when the detector is present at one of the slits, so that an observer can tell which slit the photon went through, the wavy interference pattern at the screen disappears. In order for the interference to take place, there must apparently be a 'lack of knowledge' as to which slit the particle 'actually' went thorough. ...
Roger Penrose (Professor of Mathematics, University of Oxford), The Emperor's New Mind, Oxford University Press, NY, 1990; pp 304-305
Text Box: Can the fundamental concepts of quantum physics apply to everyday classical objects as well as those in the atomic and subatomic regime? Can we meaningfully attribute wave properties to everyday objects such as a football, or does quantum theory break down at some level? In one guise or other these questions have been asked ever since the quantum theory was invented. 
On page 680 of this issue, Arndt et al., a group working under the direction of Anton Zeilinger in Vienna, report experiments showing that molecules of the fullerene C60 have wave as well as particle properties, just as predicted by quantum theory. A fullerene such as C60 is of course very much smaller than a football, but it does have a mass at least an order of magnitude greater than that of any other object whose wave properties have been previously observed. 
There is very little room for doubt concerning the correctness of the wave-particle duality postulate for fundamental physics. About 80 years ago, Prince Louis de Broglie suggested that ‘atomic’ particles such as electrons had wave as well as particle properties. This received early confirmation from the experiments of Davisson and Germer, which demonstrated electron diffraction for the first time; and the wave properties of neutrons have been exploited for at least 50 years in neutron-diffraction experiments. 
An archetypal example of wave-particle duality is the two-slit experiment (Fig. 1 [not reproduced here]). A wave crosses a screen containing two slits. The wave splits it into two parts, which are re-united on a screen, creating an interference pattern. It is the creation of this interference pattern that is an unambiguous signature of a wave. In particular, the fact that the two components cancel each other out at some points in the pattern is very difficult to explain in any other way. On the other hand, when the object reaches the screen it is always detected as a particle – hence the term ‘wave-particle duality’. 
Even on the atomic scale, wave-particle duality can raise difficult questions. For example, does the particle actually go through one or other of the two slits or does it in some way exist in both slits simultaneously? We know that if we put detectors into the slits, we will always find that the particle passes through one or other of them; but an essential consequence of such a measurement is that the interference pattern is no longer formed, so that the wave properties are no longer manifest. Results such as these led Niels Bohr to propose that the type of properties (particle or wave, for example) that we are allowed to attribute to a quantum system depend on the type of observation we make on it. Other solutions to this ‘measurement problem’ have been proposed, including the apparently outrageous ‘many worlds’ interpretation in which such a measurement divides the apparatus and everything that interacts with it into two branches that continue to exist, but are for ever unaware of each other’s existence. ... " 
Waves, particles and fullerenes, Alastair I. M. Rae (School of Physics and Astronomy, University of Birmingham, UK), Nature 401, 651 & 653 (14 October 1999)
Text Box: As we see from the above, the paradox, the mystery, the outrage, and the quest for rational interpretation – 
even definition – still continue to linger. But it shall not be for any longer. 
After more than two centuries, we now have that tenable and ultimate explanation for the two-slit phenomena. 
And the two experiments highlighted and illustrated in the previous two parts should confirm this finality – for all time.
Text Box: 1. An excerpt from the book

Section 1.20 The Two-Slit Experiment
Energy Quanta. A further insight into the particulate and highly compressible nature of the photon comes from none other than the famous two-slit experiment of Thomas Young in 1801.  
In this experiment, we identify the phenomenon called interference: When light from a single source is split into two beams, and the two beams are then recombined, the combined beam shows a pattern of light and dark fringes. Young’s conclusion, which is accepted to the present day, was that the fringes result from the fact that when the beams recombine their peaks and troughs may not be in phase (in step); thus, when two peaks coincide they reinforce each other, and a line of light results; and when a peak and a trough coincide they cancel each other, and a dark line results. 
In the physical experiment, a narrow slit is illuminated by a source, and the light from this slit is caused to illuminate two adjacent parallel slits that are mutually close. The light from the latter slits interfere, and the interference is seen by letting this light fall on a white screen. The screen will thus be covered with a series of parallel bright and dark fringes.

The ultimate concept of the photon now begs to differ on part of the classical explanation. 
It now offers insight into the true and fundamental aspect of the phenomenon. 
The bright fringe on the screen is where two ‘strips’ of coherent energy wavefronts, one from each slit, are coincident. That is, the two strips of energy particles laterally and simultaneously squeeze each other onto the same bright band area, increasing thereby in intensity just like light rays do emerging through a convex lens. This “bright” part, of course, is in keeping with the current interpretation. 
On the other hand, however: 

It is hereby predicted that a dark fringe is where such strikes are staggered evenly in time – mimicking an energy at twice source frequency. That is, a dark fringe in the two-slit experiment of Thomas Young is not an indication of destructive wave interference, or zero energy reception from the source. To the contrary, it is simply a region where the coherent energy incident on the screen excites, and is appreciably absorbed by, atomic (and molecular) energy levels corresponding to twice the source frequency. And these excitation levels of the atoms (constituting the screen) effectively remove the energy from visibility, yielding a dark area by contrast. Under magnification, the dark lines themselves will be seen to be spotty, rather than be uniformly dark; the latter being the situation should the waves really cancel in that region. By the same token, an infrared (invisible) energy, say, of 1.10 micron wavelength, will double in frequency to show visible fringes on the screen or photographic plate, that is, at 0.55 micron wavelength. (A good intensity source, though, would be required for a detectable effect).  

Any ‘tinkering’ with the experimental setup that would change the coherence of the waves through any one slit in relation to the other would obliterate the picture on the screen: Energy drain reduces intensity and wave coherence; any differential drain across the two slits – such as even the smallest for our investigative needs – reduces the resonant effect (the well and symmetrically staggered ‘hammer blows’ from the two slits) required for excitation and energy absorption at the doubly increased frequency; and energy absorption reverts to the dominant primary frequency across the screen, wiping clean the fringes. A similar situation is eventuated should the (statistical) wavelength of the energy particles get even slightly shifted in any one of the slits.  

Mass Quanta. A body of matter impelled through the classical void generates a speed-c wave through the vacuum energy field: 
The body, basically, the atom, lunges forward in recoil to net exhalation from the rear; the vacuum field opposes the change (this is none other than inertial resistance); the body recoils back; a speed-c bow shock of vacuum energy precedes the body effectively dissipating most of the body’s forward recoil momentum; over the subsequent inhalation half cycle, the body slows further as it imbibes net energy from the vacuum across the front; the cycle repeats. (See section 4.02 for full explanation.)
Therefore, in principle, moving particles of matter may be used in the two-slit experiment to produce the same effect as photons. That is, the speed-c wavefronts the sub-c particles generate through the vacuum energy field would pass through both slits to render the contrasting fringes on the screen downstream.

Hence, it is hereby predicted that this fringe effect will also persist even if the particles be barred from both slits: The mass particles – or even energy particles, including those that are considered single photons in the laboratory – are focused and fired one at a time, say, only to hit a line symmetrically between the (open) slits; and there will still emerge the bright and dark bands on the photographic plate downstream.  

    Note: In the case of single photons, there will still be wavefronts accompanying the energy through the vacuum energy field. This is by virtue of the longitudinal and transverse vibrations that are common to energy particles (as well as mass particles; section 4.07). Single-photons, though, will not be intensity sufficient for a direct visual showing as that on a screen. With mass particles, wavelengths, too, will add to the problem. As such, in any actual experiment, a large number of these single-event processes is recorded on a photographic plate to verify the effect. Section 7.12, on the phenomenon of diffraction, discusses also the intensity of energy at the bright fringes.
The phenomenon of frequency doubling has many implications. The most important has to be the health related one. Inside matter, any radiation frequency can double – even successively when source intensity is sufficiently high. (The energies emerging downstream of molecules interfere to produce the effect; see also sections 7.12 to 7.15.) Therefore, just as much as shunning ultraviolet and X-ray radiations, it would also be good practice to avoid exposure to close and prolonged radiations – from the kitchen range to the mobile telephone – especially by those prone to breast and other cancers.
Text Box: 2. An excerpt from ADDENDA 

An addendum to Section 1.20  (The Two-Slit Experiment)
If a photon has an energy, it has also a momentum. Maxwell’s theory of the electromagnetic field states that if a portion of the field traveling in a given direction has an energy E, its momentum P is given by P = E/c in that direction.
Consider a single photon of energy E zipping through the vacuum of space. Its frequency f will be given by the Planck equation, E = hf. (Derivations of equations E = hf and P = E/c, now from first principles, are given respectively in Sections 1.18 and 1.22.) 
This photonic frequency f, as we saw in Sections 1.18 and 2.01, is the frequency of the 'per-cycle' particles, or radiatons, constituting the single photon; and these perfectly elastic radiatons are the agents that vibrationally effect the momentum transfer, at frequency f and wavelength l (= c/f), in a chain reaction through the energy medium that is the classical vacuum (see also Figure 7, page 187). 

Now, the perfectly elastic radiatons of the isotropic CMB field would have the same wavelength, lo, in any direction. On the other hand, radiatons of, say, the light photon, would have a wavelength, l, that is different from (shorter than) lo. A vibrational imbalance in the vacuum field is thus eventuated by the light photon not only in the direction of its propagation but also transverse thereto, 
that is, due to the simple fact that l ≠ lo in any direction.
This transverse disturbance through the vacuum field, of course, is effected by the particle’s transverse energy (and momentum).

Thus, in reality, the particle energy traveling in a given direction has the effect of a wavefront of energy traveling in that direction. 

And it is this ‘organized’ propagating imbalance in the vacuum field that gives the energy particle its wavelike nature.
Note: In a (transparent) material medium, the transverse amplitudes of the light photon generally get more restricted. In a crystal, they can also become confined preferentially to planes, which results in the phenomenon called polarization (see Section 7.15).

From equations E = hf, P = E/c, and c = fl, we get l = h/P for the (speed-c) photon. In 1923, Louis de Broglie made the profound 
suggestion that l = h/P also governs the behavior of sub-c particles, such as electrons! This was soon verified in experiments. 
As we now know, the sub-c particle of matter is a breathing entity (Section 1.05). It inhales and exhales speed-c energy. 
The effect of this respiration is best detected at high particle speeds, that is, as bow shocks in recoil to the exhalations at the stern. Therefore, what the detectors register is the effect of these speed-c quanta – each a photon of wavelength l, momentum P, and satisfying the equation l = h/P – pulsed by the sub-c body through the vacuum of space. (For example, radiowave or microwave heating is fundamentally effected by such pulses, or wave-crest energies, that are infrared quanta; the glowing filament in a light bulb shows that even though the electrons are vibrant at only radio frequencies, the energy quanta they pulse are in the visible range. On the other hand, by virtue of their near-c speeds, cosmic-ray matter particles have the highest pulsed energies where each quantum can exceed the energy of any gamma ray produced in the lab!) It is the simple reason for the validity of expression, l = h/P, even for matter particles.

These insights should now help resolve the seeming paradox that is the wave-particle duality.
        Back to Part 1 of 3
A Synopsis The Cosmos The Spin
ADDENDA The Cosmological Redshift The Neutrino
Two-Slit Tests The Galaxy Nuclear Reactions
NASA Tests Gravity The Sun
KamLAND Test Anti-Gravity The Pulsar
UCLA Test Relativity Superconductivity
Q and A Mass-Energy Fusion Energy
 Eugene Sittampalam
 2 January 2008