The phrase "about this existence" is correct and usable in written English.
It can be used when discussing topics related to life, reality, or the nature of being.
Example: "Philosophers often ponder about this existence and what it truly means to be alive."
Alternatives: "regarding this life" or "concerning this reality".
His fellow medical officer intern from Nairobi University had only heard about the existence of this specialty in Kenya upon arrival at this particular hospital.
"John and Victor had this argument about the existence of government," Mrs. Gotbaum said.
When questioned about the existence of this type of surveillance, those in charge of it lied "for reasons of security".
"His market value as an expert has been diminished because he can be questioned about the existence of this thing".
It was interesting to hear about the existence of this "wooden whistle" award but no one will have been taken aback by the identity of its recipient.
"We found out about the existence of this outside group the same way the public did and we stand by our strong position that 527's should have no role in the political process".
"There is no intention at all to cheat or to commit an offence because the Bank Negara had been notified about the existence of this account," he said, referring to the central bank.
In reference to one surveillance system – Boundless Informant – that he said allowed the NSA to track data it was accumulating, he said: "The NSA lied about the existence of this tool to Congress and to specific congressmen in response to previous inquiries about their surveillance activities".
The homeless shelter at the Westchester County Airport is not only within walking distance of at least four schools, but also in even closer proximity to actual neighborhoods, with actual children, with actual parents who have changed their behavior after recently learning about the existence of this shelter.
