It is impossible to accelerate 9.86 m/s/s when you are less than 9.86 m/s away from c.
I cannot believe you, who have been reading the explanations about Relativity in this forum for years, make such an obvious mistake.
Accelerating 9.86 m/s/s with respect to the frame of reference of the accelerated object is perfectly possible if you can find enough energy to do so, even if you are less than 1 millimeter per second under the speed of light with respect to the frame of reference that is static in this example. This comes from the very definition of Special Relativity.
On the other hand, we accelerate subatomic particles all the time in particle accelerators, and need all the energy that a small city uses, just to accelerate a few subatomic particles to a measly 0.90c or so. Accelerating to just 0.999c the whole flat Earth is already impossible without frying it, and that is just the first 3 years or so of the 4500000000 years that the flat Earth has been supposedly accelerating.
By the way, if you are going to say that Earth cannot continue to accelerate because it is already so close to the speed of light, you are killing your own hypothesis.
I never said that. You never claimed it was accelerating it the same amount within its own FOR. If that was your question, then here is my answer "The exact same amount of energy it took to accelerate it for the first second of its existence."
So, now we are not talking about a dark energy accelerating us up, but we are now some sort of rocket, pushing itself into whatever is "up". I agree with you that this is a better solution, if one impossible solution can be better than another.
In your new model you are not just placing a frame of reference in another place, you have to carry with your flat Earth all the mass that you will convert to kinetic energy and the device that will produce this conversion.
And a mighty device it is! I had calculated many months ago that, given a perfect device with a perfect efficiency, it would have to produce the equivalent of 3 Hiroshima-sized bombs per day
for every square meter of the Earth's surface!Now, as you can imagine, the amount of mass needed to fuel such an incredible sustained push for 4.5 billion years is enormous, and it has to be carried along with us, so your flat Earth was enormously heavier when it started. Your answer ("The exact same amount of energy it took to accelerate it for the first second of its existence") is just as bad as the previous one.
And the problems with your new "solution" keep mounting. How on Earth can we have a production of energy that is bigger than a star's just below us and not get fried by it? How can it be that there is not even a small leakage of all that energy in the upward direction, that we can detect? Why don't we see some huge halo all around the Ice Wall? Why would all that energy "choose" to dissipate in the "down" direction?
You see, science is not about fancy, unsupported mathematical games. You cannot just move a Frame of Reference to where you like it to be and recalculate the equations you want to recalculate. You have a complete model and you have to respect the whole model. Or do you really believe I can send a one kilogram rocket into space just by placing the fuel in my cellar and the Frame of Reference on the rocket?