The size of the universe beyond the observable universe is currently unknown and is a subject of ongoing scientific investigation and speculation. The observable universe is the portion of the universe that we can potentially observe given the limitations of the speed of light and the age of the universe.
The observable universe has a radius of about 46.5 billion light-years, which means that the most distant objects we can see are approximately 46.5 billion light-years away from us. However, due to the expansion of the universe, those objects have actually moved even further away since the time their light was emitted.
Beyond the observable universe, there are various possibilities regarding the size and structure of the universe:
The universe may be infinite: It is possible that the universe extends infinitely beyond the observable universe. In an infinite universe, the size is not defined and there is no boundary.
The universe may be finite: The universe could have a finite size, in which case it would have some form of boundary. However, the nature of this boundary is uncertain and subject to speculation. It could be a closed universe where space curves back on itself, or it could have some other type of boundary.
It's important to note that while the observable universe has a known size, determining the size and structure of the entire universe is a complex task. Cosmologists use various models and measurements to estimate and theorize about the overall size, shape, and properties of the universe, but definitive conclusions are challenging to reach.