`One trivial point -- if you're in free fall I don't think there is any`

`Rindler boundary. You're following a geodesic, and not "really"`

`accelerating.`

`You can't just apply SR in the curved spacetime around a gravitating`

`mass and get the right answer. In fact, while you certainly /can/ apply`

`SR in an accelerated frame (with some care), you can't really apply it`

`at all in non-flat space. The math of SR assumes a fixed metric, which`

`you haven't got in a gravitational field. In general, while I don't`

`_think_ there is, I have no idea how you'd go about determining for sure`

`whether there's an event horizon due to acceleration when free-falling`

`in a gravitational field.`

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On 09/22/2016 12:48 PM, Bob Higgins wrote:

I have read Dr. McCulloch's book and find his theory interesting.However, my training in RF gives me a different perspective on wavephenomena that doesn't seem to match up with his theory. In histheory, he drops out wavelengths of EM background radiation that wouldbe filtered in the frequency domain due to the Rindler boundary whichmoves closer to the object depending on acceleration. However, in thetime domain these waves would have to propagate the distances to thediscontinuity and back before any cancellations could occur. Theboundaries in question are huge distances away. For example, for afree fall acceleration on the Earth (9.8m/s^2), the boundary would bechanged to 10 light years away. The change in inertial mass inducedby an acceleration will not know of the discontinuity until twice thetime to the discontinuity. That would mean that the object beingaccelerated at 9.8m/s^2 should not know of the boundary for at least20 years. If the object instantaneously experienced a change ininertial mass, it would seem to violate causality by this theory.I have written to Dr. McCulloch to ask him how I get past thisunderstanding. Do any of you have an opinion on this issue?On Mon, Sep 19, 2016 at 6:14 AM, Jack Cole <jcol...@gmail.com<mailto:jcol...@gmail.com>> wrote:http://physicsfromtheedge.blogspot.com/2016/09/unruh-radiation-confirmed.html <http://physicsfromtheedge.blogspot.com/2016/09/unruh-radiation-confirmed.html>