Undergrad Verifying Speed of Light Varies by Direction

[Andy Lee]

TL;DR

A method for measuring the one way speed of light.

Note, it possible to determine if the speed of light varies depending on direction, with the use of a single clock. Simply send a beam and reflect it back, but on the return trip introduce a medium to slow the beam.

Three cases, T1, T2, T3 are total travel times.

T1: assume light is the same speed in both directions (prior to introducing medium).
T2: assume light is faster on the outbound trip (prior to introducing medium).
T3: assume light is faster on the inbound trip (prior to introducing medium).

Let T1 = T2 = T3 without the medium.

Calculations show that with the medium, it is necessarily the case that T3 < T1 < T2

Sample below with c = 300,000 km/s and distance 1 km for convenience.

First without the medium

T1: Outbound 300,000 km/s, 1 km then inbound 300,000 km/s, 1km. T1 = 1/150,000 seconds.

T2: Outbound 600,000 km/s, 1 km then inbound 200,000 km/s, 1 km. T2 = 1/150,000 seconds.

T3: Outbound 200,000 km/s, 1 km then inbound 600,000 km/s, 1 km. T3 = 1/150000 seconds.

T1 = T2 = T3 ... impossible to verify which case exists.

Second with the medium (inbound velocity slowed by 50%)

T1: Outbound 300,000 km/s, 1 km then inbound 150,000 km/s, 1km. T1 = .00001 seconds.

T2: Outbound 600,000 km/s, 1 km then inbound 100,000 km/s, 1 km. T2 = .000017 seconds.

T3: Outbound 200,000 km/s, 1 km then inbound 300,000 km/s, 1 km. T3 = .0000083 seconds.

T3 < T1 < T2 ... possible to verify which case exists.

 

[Vanadium 50]

And how, pray tell, do you verify that your medium slows the light by 50% irrespective of direction?

 

[Andy Lee]

50% is for example only. Use any medium, guaranteed to slow light.
We're slowing the light only in one direction in each case (inbound).

 

[Vanadium 50]

That doesn't plug the hole in your argument. How do you verify that your medium slows light by the same fraction irrespective of direction.

 

[Andy Lee]

In all cases the light is traveling through the medium in the same (inbound) direction.

 

[Vanadium 50]

I'm wasting my time, aren't I. There is aboslutely nothing that will convince you that everyone else is right and you are wrong, is there.

Your medium has to slow light that is traveling in the 300,000 km/s diresction to 150,000 km/s, light that is traveling in the 200,000 km/s direction to 100,000 km/s , light that is traveling in the 600,000 km/s direction to 300,000 km/s, etc. How do you prove this?

 

[Dale]

This isn’t a one way measurement.

This isn’t a QM question.

This isn’t correctly analyzed (as already pointed out)

This isn’t consistent with the professional scientific literature

This is closed