"vanishing over time" is correct and usable in written English.
You can use it to describe something that is dwindling away, gradually disappearing, or being forgotten. For example: "Grandma's stories about her childhood are slowly vanishing over time."
Without deeper purpose, the satisfaction and happiness of external rewards always vanish over time.
After 8 weeks, remodeling "back to normal" may occur and initial improvements in implant integration may vanish over time.
Other idiosyncrasies have all but vanished over time.
The extrasensory powers of Schooler's subjects didn't decline — they were simply an illusion that vanished over time.
The extrasensory powers of Schooler's subjects didn't decline they were simply an illusion that vanished over time.
While the study showed some health improvements for the primary cook in the household during the first year after installation, the effect vanished over time as proper use and maintenance of the new stove declined.
When I spoke with Pablo Chavez, in Google's Washington office, he told me that the company is experimenting with "crumbling cookies," or smaller cookies "that collect a limited amount of data" and vanish over time.
But they will prove to be cheap financing for the government, and it would be well advised to keep selling them as long as it has any need to raise cash -- although that need will vanish over time, of course, as all the projected budget surpluses roll in.
To be on the latest level, proprietary approaches vanish over time.
Due to high dynamics of the VANET, clusters are created (new clusters added to the system) and vanished over time, and the total number of clusters created over a period of time defines the cluster formation rate.
