...the Earth is not stationary but travelling upwards at by now immense speed, since it is claimed Earth is accelerating upwards at 9.8 ms-2. Apparently everything else we see - sun, moon and stars - is also accelerating at the same rate with the Earth. This is called Universal Acceleration and is this site’s explanation of what the rest of the world calls gravity.
If everything is accelerating at the same speed and direction then this 'acceleration' would not be discernible, just like when you are traveling in an airplane at 400 mph along with the plates, napkins, and chairs. There is no sense of motion, thus there would be no 'force' and you would still have to explain gravity. BTW, 'up' would have no meaning.
You may be confusing "acceleration" and "velocity". Humans have no means of detecting velocity (although we sometimes think we can, from clues such as perception of relative movement, engine noise, wind on our face etc). We can, however detect acceleration, using our sense of feeling, sense of self and our inner-ear thingies. When the aeroplane, passengers, chairs and napkins are all travelling at 400 mph then, yes, there is no perception of velocity. When the First Officer bounces the thing onto the runway, however, that is an acceleration of the aeroplane, and all the passengers, chairs and plates feel it.
The FE concept is that UA is accelerating the Earth,
and celestial objects at 9.8 m/s/s but not (for some reason) people, animals, buildings, chairs and napkins. So the FE concept of what we Globies call gravity, is that everything on the planet is being pushed up by the earth and that is the effect we feel as gravity.
And as Longtitube said, don't think that everyone who posts on this site is a Flattie; its a forum.