Even if the earth would "accelerate" more (which it doesn't Because accelerating means an increase in velocity), then what would it look like from the outside? Would the earth stand still or move with constant speed? The possibility of acceleration is not given, because from the outside it would look like the earth is moving past the speed of light.
Even if it would change the space, the earth would have to gain velocity to get faster.
Relativity is making this whole concept of a flat earth falling apart.
No. Here are a few things to understand about special relativity:
1. Absolute velocity doesn't matter. All that matters is how fast you are moving
relative to other objects. If everything else is accelerating along with you, then there is absolutely no way to know how fast you are going, and frankly, it doesn't matter how fast you are going.
2.
You can't combine two velocities by adding them. The difference in velocity between any two objects asymptotically approaches the speed of light as they accelerate away from each other. It gets closer and closer to the speed of light but never reaches it, even under constant acceleration.
For example, let's say Bob, Joe, and Pam are all travelling in the same direction. Bob is travelling at 10 m/s, Joe is travelling 10 m/s faster than Bob, and Pam is travelling at 10 m/s faster than Joe. Does this mean that Pam is travelling 20 m/s faster than Bob? Nope! Pam's actual speed relative to Bob is something like 19.9999 m/s. Velocity addition is not linear.
then what would it look like from the outside? Would the earth stand still or move with constant speed?
If the earth were accelerating at a constant rate, and you were not, this is what it would look like:
1. The earth would appear to move at an accelerating rate away from you. This acceleration would
appear to decrease as the earth approaches the speed of light relative to you.
2. The earth would appear to be getting flatter in the direction it is accelerating.
3. The people on earth would appear to age slower from your point of view. Clocks would appear to move slower and slower.
4. Light reaching you from the earth would appear red-shifted, assuming the earth is moving away from you. Everything would look reddish, and then eventually infrared.
According to someone on the earth, everything on earth would still look and behave normally. However, looking back at you, they would say that YOU are the one who is slowing down, becoming flatter, redder, etc.
Flat earthers need to accept the earth is a sphere. There are no logical arguments that would support a flat earth
Well yeah. That's why there are hardly any flat earthers willing to participate in debate left on this site. But special relativity isn't a great argument against it.