Double Slit Experiment

The Challenge

The double-slit experiment shows that when individual electrons or photons are sent through a two-slit apparatus one at a time, they:

1. Build up an interference pattern identical to classical wave interference
2. Each particle creates a single detection event at a specific location
3. The pattern emerges gradually as individual detections accumulate
4. Which-path detection destroys the interference - if you measure which slit the particle went through, the pattern disappears
5. Delayed-choice experiments show the pattern depends on measurement setup decided after the particle has "already passed through the slits"

Quantum mechanics explains this through wave-particle duality: particles are both waves and particles simultaneously, with the wave function "collapsing" upon measurement.

Why This Matters

The double-slit experiment is frequently cited as the central mystery of quantum mechanics. Feynman called it "a phenomenon which is impossible, absolutely impossible, to explain in any classical way."

If AAM can provide a clear mechanical explanation using only waves in the aether (no wave-particle duality, no collapse), it would demonstrate that the "quantum mystery" is actually just misinterpretation of classical wave behavior.

Conventional QM Explanation

The Photon Picture

• Light consists of discrete photons
• Each photon is a "wave-particle"
• The photon wave function passes through both slits
• Upon detection, the wave function "collapses" to a single point
• The interference pattern emerges from quantum probability amplitudes

Key QM Claims

• A single photon "interferes with itself"
• The photon is "in a superposition of going through both slits"
• Measurement causes wave function collapse
• Which-path information is incompatible with interference (complementarity)
• No classical wave theory can explain this behavior

The "Impossibility" Claim

Bell and others argued that no local realistic theory (where properties exist before measurement and interactions are local) can explain:

• The gradual buildup of the interference pattern
• The fact that individual events are unpredictable
• The destruction of interference by which-path measurement

AAM Mechanical Explanation

What Actually Happens - The AAM View

1. Wave Emission from Source

• Conventional: A single photon (particle) is emitted toward the barrier
• AAM: An aether wave is emitted - a mechanical disturbance propagating through aether
• The wave is caused by an atomic event at the source
• Wave properties: definite amplitude, frequency, phase, polarization
• Wave propagates through aether medium at light speed (c)

2. Wave Interaction with Two-Slit Barrier

• Conventional: The photon "goes through one slit OR the other OR both"
• AAM: The wave encounters both slits simultaneously
• Wave passes through both slits at the same time, with the same phase
• Each slit becomes a secondary wave source (Huygens' principle)
• Two waves emerge from the slits with coherent phase relationship

3. Wave Propagation to Detection Wall

• Conventional: The photon wave function interferes with itself
• AAM: The two waves from the slits interfere - standard wave behavior
• Constructive interference: Where wave crests align, amplitude is maximum
• Destructive interference: Where crest meets trough, amplitude cancels
• Creates spatial pattern of varying wave amplitude across detection wall
• This is identical to water waves, sound waves, or any wave through a medium

4. Detection Mechanism (Critical Insight)

• Conventional: Wave function collapses, photon appears at random location
• AAM: Continuous wave has limited amplitude and duration
• Wave strikes detector atoms across entire interference pattern region
• Most important: Wave amplitude varies with position (interference pattern)
• Detector atoms have resonance thresholds - require minimum wave amplitude

Detection is probabilistic because:

• Wave amplitude is limited (finite energy in the pulse)
• Multiple detector atoms competing for resonance
• Thermal fluctuations and detector noise
• Exact timing of wave arrival vs detector state

5. First Detection Event

• Where wave amplitude is highest, detection probability is highest
• Eventually (within microseconds) one detector atom reaches resonance threshold
• This detector "clicks" - registers the event
• This single click tells experimenters they sent a "single photon"
• But it was actually a wave pulse of limited total energy
• The wave-energy has now been absorbed by detector material

6. Pattern Buildup Over Many Trials

• Process repeats with each new wave pulse from source
• Each wave creates same interference pattern on detection wall
• Each detection event occurs at one location within that pattern
• Locations vary randomly, but weighted by interference pattern amplitude
• After many detections, the pattern becomes visible
• High-amplitude regions get more clicks (bright fringes)
• Low-amplitude regions get fewer clicks (dark fringes)

Quantitative Predictions

Interference Pattern Mathematics

Classical Wave Interference:

For two slits separated by distance d, waves from each slit travel different path lengths to reach a point on the detection screen at angle θ:

Path difference: ΔL = d sin(θ)

Constructive interference (bright fringes) occurs when:

• d sin(θ) = nλ where n = 0, ±1, ±2, ...
• Waves arrive in phase, amplitudes add

Destructive interference (dark fringes) occurs when:

• d sin(θ) = (n + ½)λ where n = 0, ±1, ±2, ...
• Waves arrive out of phase, amplitudes cancel

Wave Amplitude at Screen

At position x on screen distance L from slits:

\( A(x) = A_0 \cos\left(\frac{\pi dx}{\lambda L}\right) \)

Where A₀ = amplitude of wave from single slit (factor of 2 from two slits interfering)

Detection Probability

AAM predicts detection probability proportional to wave intensity:

\( P(x) \propto I(x) = |A(x)|^2 \)

\( P(x) \propto \cos^2\left(\frac{\pi dx}{\lambda L}\right) \)

This exactly matches the observed interference pattern!

Experimental Validation

Tonomura's Single-Electron Experiment (1989)

• Electrons sent one at a time through double slit
• Pattern builds up gradually over hours
• Final pattern matches I(x) ∝ cos²(πdx/λL)
• AAM prediction: MATCHES

Quantitative Specifics

• Slit separation: d ≈ 2 μm
• Wavelength: λ ≈ 50 pm (for 50 keV electrons)
• Screen distance: L ≈ 1 m
• Fringe spacing: λL/d ≈ 25 nm

AAM Explanation:

• Each electron creates aether wave with λ = h/p (de Broglie relation)
• This wavelength emerges from planetron orbital structure in source atoms
• Wave passes through both slits
• Interference creates pattern
• Detection occurs where wave amplitude exceeds threshold
• Pattern gradually becomes visible as detections accumulate

Which-Path Detection Destroys Interference

The Experimental Observation

Setup:

• Place detector at one slit to determine which path the particle took
• Result: Interference pattern disappears
• Without which-path detector: Interference pattern visible
• With which-path detector: No interference, two separate single-slit patterns

QM Interpretation:

• Measurement "collapses" the wave function
• Gaining which-path information makes particle "real"
• Complementarity principle: Can't have both particle and wave information

AAM Mechanical Explanation

1. Detection Mechanism Perturbs the Wave

To detect "which path," the detector must:

• Interact with the wave passing through the slit
• This interaction requires energy transfer from wave to detector
• Energy extraction reduces wave amplitude

2. Reduced Wave Amplitude Affects Interference

Original setup (no which-path detection):

• Full wave amplitude passes through both slits
• Strong interference pattern on detection screen

With which-path detector:

• Wave passing through monitored slit loses amplitude
• Wave amplitude from two slits becomes unequal: A₁ ≠ A₂
• Interference visibility reduced

3. Complete Destruction Requires Strong Interaction

For complete pattern destruction:

• Which-path detector must absorb significant wave energy
• This leaves minimal amplitude to create interference
• Remaining amplitude creates primarily single-slit diffraction pattern

Quantitative Analysis

Interference visibility:

\( V = \frac{I_{max} - I_{min}}{I_{max} + I_{min}} \)

• With equal amplitudes: V = 1 (perfect interference)
• With unequal amplitudes: V = 2A₁A₂/(A₁² + A₂²) < 1

If which-path detector reduces amplitude to A₂ ≈ 0:

• V → 0 (no interference)
• Pattern becomes two separate single-slit patterns

Delayed-Choice Experiments

The Experimental Setup

Wheeler's Delayed-Choice Thought Experiment:

1. Particle/photon enters interferometer with two paths
2. After particle has "already chosen" its path, experimenter decides:
   • Option A: Measure which path (insert which-path detectors)
   • Option B: Recombine paths (allow interference measurement)
3. Result depends on final measurement choice, not initial state

QM Interpretation:

• The past is not determined until measured
• Retrocausality or "delayed collapse"
• Particle was in superposition even after passing through slits
• Final measurement determines what "already happened"

AAM Explanation: No Retrocausality Needed

1. The Wave Properties Are Always Definite

• Wave from source always has definite amplitude, phase, frequency
• Wave always passes through both paths/slits
• Wave properties don't depend on future measurements
• Nothing about the past changes

2. What Changes Is What We Measure

Interference Measurement:

• Allows waves from both paths to recombine
• Detector positioned to measure combined amplitude
• Result shows interference pattern

Which-Path Measurement:

• Prevents path recombination (inserts detection at path)
• Or: Measures idler photon in correlated pair
• Effectively destroys interference for those events
• Result shows no interference

3. The "Delayed" Part Is Irrelevant

The wave has already:

• Passed through both slits
• Created interference pattern in space
• Propagated to detection screen

The "choice" is about:

• Which aspect of the wave we measure
• How we set up our detector configuration
• What information we extract

Nothing travels backward in time. No retrocausality needed.

Summary

What This Accomplishment Means

For AAM

• Demonstrates wave-only explanation viable
• No wave-particle duality needed
• No wave function collapse needed
• Everything reduces to space, matter, motion (Axiom 1)

For Physics

• Challenges "impossibility" of classical explanation
• Shows Feynman's claim ("impossible to explain classically") was wrong
• Provides simpler alternative to quantum mysticism
• Restores physical reality to light propagation

Confidence Assessment: HIGH

This is actually much simpler than the entanglement challenge:

• Classical wave interference is well-understood
• No Bell inequalities to satisfy
• No complex correlation calculations
• Aether provides natural medium for waves
• Explanation more intuitive than QM

Connections to Other AAM Principles

Related Axioms

• Axiom 1: All phenomena reduced to space, matter, motion. Light is wave motion in aether matter.
• Axiom 6: Each wave has unique properties (amplitude, phase, frequency). Each detection event unique.
• Axiom 7: Energy conserved: source → wave → detector. Why which-path detection destroys interference (energy extraction).

Related Topics

• Quantum Entanglement: Same wave-based approach, detection mechanism similar
• Photoelectric Effect: Same detection mechanism, resonance threshold explains discrete behavior