The phrase "are simultaneous with" is correct and usable in written English.
It can be used to indicate that two or more events or actions occur at the same time.
Example: "The fireworks display and the concert are simultaneous with each other, creating a spectacular atmosphere."
Alternatives: "occur at the same time as" or "happen concurrently with".
The variations are not consecutive but are simultaneous, with certain members of the orchestra improvising their own variations at the same time on the same tune.
A second inertial observer, who is in relative motion with respect to the first, however, will disagree with him regarding which events are simultaneous with that given event.
This was what I meant when I spoke of impressions which invited the intellect, or the reverse --those which are simultaneous with opposite impressions, invite thought; those which are not simultaneous do not.
The book that spills forth from this dramatic scene suggests that, as Robert Penn Warren once wrote, "you live through... that little piece of time that is yours, but that piece of time is not only your own life, it is the summing-up of all the other lives that are simultaneous with yours.
So, builders and fathers are simultaneous with, not temporally prior to, their proper effects.
According to STR, for many events there is no absolute fact of the matter as to whether those events are simultaneous with now.
There have been claims that well-publicised "price cuts" at Tesco can be simultaneous with price rises on certain products.
The negotiations were simultaneous with Amani's negotiations, but our proposals were turned down by the agent".
The bombing, apparently planned for Manhattan, was to be simultaneous with another terrorist explosion that did occur in Naples, Italy.
Slope relaxation processes were simultaneous with incision thereby indicating that both processes were likely climate driven.
