- var_dump: documentation ( source)
<?php
$date = new DateTime('2010-01-10 12:00:00', new DateTimeZone('America/Toronto'));
$gmt = new DateTime('2010-01-10 12:00:00', new DateTimeZone('UTC'));
var_dump($date->format("U") == $gmt->format("U"));
$date = new DateTime('now', new DateTimeZone('America/Toronto'));
$gmt = new DateTime('now', new DateTimeZone('UTC'));
var_dump($date->format("U") == $gmt->format("U"));