I feel somewhat foolish, but really haven't been able to find a way to do this. I'm using the Timeline Map module, and need to have the items span from when they were created until the current time. I've tested and the module works with, say, node modified in as the second time. But I can't figure out any way to get the module to recognize a time output from the custom PHP field.

What code would I put in there to output the current datetime / timestamp / etc in a manner that is expected by this module? I feel like it's a simple thing, but it's turned out unexpectedly complex.