1. Q: Didn't Ron Drever already do Magnetic Suspensions in the 80's ?

• A: Yes and no. Ron magnetically levitated a test mass with a mirror on. It was mainly soft in the beamline direction. A main goal of that research was to levitate the test mass so as to eliminate any touching of the test mass. The noise of that suspension in the GW band was never measured. The suspension idea we are working on will be soft in all 6 degrees of freedom and is mainly for seismic isolation - not to reduce suspension thermal noise. It will suspend the penultimate mass, not the test mass.

2. Q: How can you glue magnets onto the suspension without screwing up the mirror thermal noise?

• A: We are not proposing to put any magnets on the mirror. We are making a magnetic vibration isolation system for the penultimate mass.

3. Q: Have you thought about the ambient magnetic fields? Doesn't that make magnets a bad idea?

• A: Yes, there is an ambient magnetic field and it fluctuates. The proposed design is designed to be immune to dipole and quadrupole fields.

4. Q: What about Barkhausen noise? Doesn't that make magnets a bad idea?