Einstein Synchrony Convention Simulation

This simulation demonstrates the epistemological limits of measuring the one-way speed of light. Measuring light's one-way speed requires two synchronized clocks, of which the synchronization process also requires exchanges of signals at a known speed, hence measurement is inherently circular.

Round-Trip Speed (Mean): $c$

Directional Bias (Anisotropy)

$c_{\rightarrow}$: $c$ $c_{\leftarrow}$: $c$

Adjusting the Directional Bias changes the true physics of the top frame. However, under the standard Einstein Synchrony Convention, the clocks automatically de-synchronize to compensate. Consequently, as demonstrated in the bottom frames, the measured speed of the pulse will mathematically cancel out to a constant 1.0c in all reference frames.

Proposed Solution	Methodology	Epistemological / Physical Limit
Einstein Synchrony (Demonstrated in View 1)	Use a light signal from Point A to synchronize a clock at Point B. A flash is emitted from clock A at `t₀`, and clock B registers the arrival, setting its time to `t₀ + d/c`.	Circularity: This method inherently assumes that the one-way speed of light is exactly `c` in order to calibrate the clock at B. You cannot use this method to empirically measure the one-way speed because the synchronization protocol itself mathematically defines the one-way speed as `c`. This is why the clocks in View 1 de-synchronize.
Slow Clock Transport	Synchronize two clocks together at Point A, then physically move one of the clocks infinitesimally slowly to Point B to avoid using light for synchronization. By moving at speed `v → 0`, one attempts to render kinematic time dilation negligible.	Time Dilation Anisotropy: While the immediate time dilation effect approaches zero as you slow down, the time required for the journey approaches infinity. When integrated over the entire trip, the accumulated time dilation introduces a strictly non-zero time shift. Correcting for this shift requires already knowing the one-way speed of light, permanently sealing the circularity loop.
High-Speed Observation (Demonstrated in Views 2 & 3)	Avoid endpoint clocks entirely. Instead, use an independent high-speed camera offset from the path to visually record a light pulse traveling across a measured distance. By analyzing the camera frames, one expects to directly calculate the geometric speed of the pulse.	Observational Signal Lag: For the camera to record the pulse, secondary photons must travel from the pulse's path to the camera's lens. If the speed of light is truly anisotropic, these observation photons will also travel at different speeds depending on their specific angle to the lens. This staggered delay exactly cancels out the underlying anisotropy, projecting a perfect illusion of constant `1.0c` to the observer (as seen in View 3).
Anisotropic Modeling	Assume light is directional (`c_→ ≠ c_←`) and hunt for measurable shifts or asymmetries in other physical phenomena, such as particle decay rates, electromagnetic field propagation, or relativistic momentum.	Universal Conspiracy: Adjusting the one-way speed of light mathematically functions as a purely administrative change to how we label time coordinates. The universe does not care how we label time. Nature's fundamental mechanics (like length contraction and time dilation) warp in perfect, absolute lockstep with the coordinate shift. As a result, no physical experiment can ever detect the shift, because the measuring instruments themselves warp to hide the difference.

Proposed Solution

Methodology

Epistemological / Physical Limit

Einstein Synchrony
(Demonstrated in View 1)

Use a light signal from Point A to synchronize a clock at Point B. A flash is emitted from clock A at t₀, and clock B registers the arrival, setting its time to t₀ + d/c.

Circularity: This method inherently assumes that the one-way speed of light is exactly c in order to calibrate the clock at B. You cannot use this method to empirically measure the one-way speed because the synchronization protocol itself mathematically defines the one-way speed as c. This is why the clocks in View 1 de-synchronize.

Slow Clock Transport

Synchronize two clocks together at Point A, then physically move one of the clocks infinitesimally slowly to Point B to avoid using light for synchronization. By moving at speed v → 0, one attempts to render kinematic time dilation negligible.

Time Dilation Anisotropy: While the immediate time dilation effect approaches zero as you slow down, the time required for the journey approaches infinity. When integrated over the entire trip, the accumulated time dilation introduces a strictly non-zero time shift. Correcting for this shift requires already knowing the one-way speed of light, permanently sealing the circularity loop.

High-Speed Observation
(Demonstrated in Views 2 & 3)

Avoid endpoint clocks entirely. Instead, use an independent high-speed camera offset from the path to visually record a light pulse traveling across a measured distance. By analyzing the camera frames, one expects to directly calculate the geometric speed of the pulse.

Observational Signal Lag: For the camera to record the pulse, secondary photons must travel from the pulse's path to the camera's lens. If the speed of light is truly anisotropic, these observation photons will also travel at different speeds depending on their specific angle to the lens. This staggered delay exactly cancels out the underlying anisotropy, projecting a perfect illusion of constant 1.0c to the observer (as seen in View 3).

Anisotropic Modeling

Assume light is directional (c_→ ≠ c_←) and hunt for measurable shifts or asymmetries in other physical phenomena, such as particle decay rates, electromagnetic field propagation, or relativistic momentum.

Universal Conspiracy: Adjusting the one-way speed of light mathematically functions as a purely administrative change to how we label time coordinates. The universe does not care how we label time. Nature's fundamental mechanics (like length contraction and time dilation) warp in perfect, absolute lockstep with the coordinate shift. As a result, no physical experiment can ever detect the shift, because the measuring instruments themselves warp to hide the difference.

Proposed Measurement Solutions