- #1
alas666
- 11
- 2
Poster has been reminded that we do not allow discussions about Reactionless Drives
- TL;DR Summary
- reactionless drive, relativistic Doppler, reflection from moving mirror
Here is a concept suggesting reactionless drive:
Setup: A light pulse of wavelength l0 bouncing between 2 mirrors one on the left - ML and one on the right - MR. Each mirror oscillates perpendicularly to light travel direction attaining relativistic speeds vl, vr. Light pulse is timed so it reflects from the ML, moving with vl, when it is moving in the same direction as light pulse, while reflection from MR happens when vr opposes light direction.
Analysis: The reflecting photon momentum change is dp = 2h/l. The wavelength lL=l0((1+vl/c)/(1-vl/c))^-1 is red shifted in ML reference frame, while MR wavelength IR = l0*((1-vl/c)/(1+vl/c))^-1 is blue shifted, as per wikipedia relativistic Doppler effect. The traveling light is changing a wavelength at each reflection in setup reference frame: lL = l0 (1-(vl/c)^2)/(1-2vl/c+(vl/c)^2) - red shifted, IR = I0 (1-(vr/c)^2)/(1+2vr/c+(vr/c)^2) - blue shifted (see https://arxiv.org/pdf/1207.0998.pdf). To maintain wavelength unchanged after 2 bounces one have to assure that vl, vr selected correctly.
Conclusion: Because change of the momentum in mirror reference frame is different for MR and ML there is a resulting net momentum change impacting setup.
where have I wronged ?
Setup: A light pulse of wavelength l0 bouncing between 2 mirrors one on the left - ML and one on the right - MR. Each mirror oscillates perpendicularly to light travel direction attaining relativistic speeds vl, vr. Light pulse is timed so it reflects from the ML, moving with vl, when it is moving in the same direction as light pulse, while reflection from MR happens when vr opposes light direction.
Analysis: The reflecting photon momentum change is dp = 2h/l. The wavelength lL=l0((1+vl/c)/(1-vl/c))^-1 is red shifted in ML reference frame, while MR wavelength IR = l0*((1-vl/c)/(1+vl/c))^-1 is blue shifted, as per wikipedia relativistic Doppler effect. The traveling light is changing a wavelength at each reflection in setup reference frame: lL = l0 (1-(vl/c)^2)/(1-2vl/c+(vl/c)^2) - red shifted, IR = I0 (1-(vr/c)^2)/(1+2vr/c+(vr/c)^2) - blue shifted (see https://arxiv.org/pdf/1207.0998.pdf). To maintain wavelength unchanged after 2 bounces one have to assure that vl, vr selected correctly.
Conclusion: Because change of the momentum in mirror reference frame is different for MR and ML there is a resulting net momentum change impacting setup.
where have I wronged ?
