The River and Honey Theories
There is only one expression or consciousness or awareness of time that can be experienced while in the physical body. There is one and only one moment in time that we can possibly experience while in the physical body. That moment is the NOW. Our concept of "Time" is a series of succesive NOWS that are strung together like barges tethered to each other on a river. We are not in the past, it is gone. We are not in the future, it hasn't come yet.
We are only here, right now. This moment, oops, there it just went....Wait! Here comes another....damn! thats one's gone into the past now.....
Say, that means we are living in eternity.....Hmmm that's way too uncomfortable to deal with, eternity is a aweful long time to deal with...
Can't we break this up into periods that don't scare folks?, Thus Light and Dark, Days, Nights, Cycles of the Moon, Weeks, Months, Cycles of the Seasons, Revolution of the Earth around the System, Years, Sun Dials, Chinese Water Clocks, Sand Clocks, Sand Hour Glass, Mechanical Time Pieces, Electronic Time Pieces based on quartz crystal.....
Ah, thats better, small steps when added together make larger steps. Time's not such a hard thing to deal with now thanks to devision that works and it all fits together.... but nothing has changed. We have created mental concepts and found a way to measure parts of that mental concept, but our only connection to time is the passage from moment to moment, the now to the next now and so on.
When we hear something like "You'll Rot In Hell For Eternity", At first impression that sounds like being stuck in a bus station in Hoboken at 2:10 am waiting for the 6:30. Depending upon your frame of mind, your attention span and or the presence of a good book, (or absence) time could very well pass like an eternity in hell which entirely depends on the amount and condition of wino's present.
Point is, time and its passage is relative. While still in the physical body, one can not change its speed of 'passage'. OBE, out of the body experiences may offer a different aspect of the passage via astral travel and such using the various modes of perception / vehicles that Soul has at it's beck and call.
Short of everyone here taking up a collection and having one of us test a "machine" for a few weeks and then someone else here test it also, I wouldn't trust a Time Machine as far as it measured from side to side.