The phrase "acting simultaneously" is correct and usable in written English.
It can be used to describe two or more actions occurring at the same time.
Example: "The dancers were acting simultaneously, creating a beautiful and synchronized performance."
Alternatives: "performing at the same time" or "occurring concurrently".
The search problems are formulated according to three different limiting criteria acting simultaneously.
It results from multiple soil processes acting simultaneously but at different scales.
To have a defendant acting simultaneously as both prosecutor and judge is not compatible with any principle of law".
The answers to the major questions in ecology require an understanding of the relative effects of many variables acting simultaneously.
To bring the benefit of scientific research to agriculture, experiments entailing many causes acting simultaneously are required.
The varying acceptability of transgenic plants depends on a number of factors and sometimes on several factors acting simultaneously.
I saw myself as acting simultaneously in real time and in a film noir, so I was both tracking my quarry and watching myself do it.
The second case establishes that kinetics during the enzymatic cleaning step can be followed by UV and shows that different cleaning mechanisms are acting simultaneously.
Agent-based modeling is a technique for computational simulation of complex interacting systems through the specification of the behavior of a number of autonomous individuals acting simultaneously.
Although there is good knowledge about the impacts of individual stressors, there is less understanding of the consequences of several stressors acting simultaneously.
It is shown that the control authority can indeed be improved near a selected resonance even with multiple pairs of piezoelectric patches and active passive circuits acting simultaneously.
