-2

Let's assume we have a long, narrow tube perpendicular to a wall that emits light (similar to the ones doctors use to look at radiology films). On the other side of the tube there is a sensor (mounted on a wall), that measures the intensity of the light coming through the tube. (no other light can reach the sensor, it is masked in some way). Now we make the tube move, describing a circle of a certain radius (parallel to the two walls). The sensor is large enough to cover the trajectory of the tube). Both the source of light and the sensor are static, they don't move at all.

As the speed of the tube increases, assuming it is long and narrow enough, the intensity of the light that passes through it should decrease, until at some point, no photon makes it to the other end, and the sensor eventually reads 'zero'.

No clocks and no mirrors are required, and it's not even necessary to reach the speed when the reading is zero, the variations of the readings as the speed of the tube increases should be enough.

Why couldn't this be used to determine the one-way speed of light?

Qmechanic
  • 220,844
Jony
  • 171

1 Answers1

1

This experiment seems to be analogous to the one leading to the so-called aberration of stars when they are observed through a telescope from earth. Due to the speed of earth, a telescope has to be tilted forward by a certain angle from the true direction of the star in order to see the star. Otherwise the light from the star would not pass the telescope. This aberration has been used by James Bradley in the 1700s to estimate the speed of light pretty accurately. Wikipedia

freecharly
  • 18,177