Could “Time” Actually be a Spatial Dimension?
I’ve pondered the meaning of time since before I can remember. I’ve even written an article about my admittedly zany theory on the “Shape of Time”. Learning about time dilation is also interesting since the passage of time is based on one’s accelerating frame of reference. But, is there such a thing as a TRUE non-accelerating frame of reference?
Special Relativity tells us that everything is… well, relative. For example, think about how one can measure the speed of an object, such as a car on a roadway.
Let’s say you’re standing still on the side of the road watching traffic. There is a utility pole on the far left of the strip of road, and another one on the far right. From your still frame of reference, you can measure the speed of a car by timing how long it takes to travel the distance in between both utility polls.
Let’s say the distance between the polls is one mile, and the car was able to clear that distance in one minute. Well, their speed would be 60 mph from your stationary frame of reference.
But, just think about what would happen to that measurement if you were driving in a car along side the one you are measuring. Considering you are now accelerating, relative to the two utility polls and the car being measured, your measurement of the other car’s speed is actually going to be much different.
Not only that, but if you were accelerating in the opposite direction of the car being measured, your results would again be different from the first two!
Now, when you take that concept and blow it up to the cosmic scale, things get much more complicated in regard to time. But when you think about it… can an object in the Universe ever NOT have an accelerating frame of reference?
The Need for Speed
Let’s pretend that you’re still standing on the side of that road watching traffic. You are not moving, and relative to the two utility polls, you are completely stationary.
But, are you actually stationary? Again, relative to the utility polls you are stationary, but does that mean the utility polls are stationary? And if they are stationary… relative to what?
Okay, so maybe those polls are stationary relative to a very large tree you can see in the distance… but how can you be sure that large tree is stationary?
Well, what if you were instead standing still on the moon and looking at the same roadway, watching the traffic through a telescope? Would everything in that scene (aside from the cars) still be stationary?
Well, since you’re on the moon, no, they would not appear to be stationary. In fact, neither would you! You’d be on a giant floating rock hurdling through space while trying to measure an event occurring on another floating rock accelerating in its own frame of reference.
The point is, even when you’re standing still on Earth, you aren’t actually stationary. You are CONSTANTLY accelerating through space at a tremendous speed — or, velocity.
How fast, exactly?
The exact number isn’t just a straight up answer, and it depends a lot on frame of reference. However, the estimated accumulated figure I recently came across is somewhere in the 500,000 miles per hour range. While that is quick, remember that the speed of light is roughly 186,000 miles per SECOND.
Just think about it. The Earth rotates on its axis at a specific speed (or, technically “frequency”) which means if you’re standing still, say on the equator, you’re actually rotating, and therefore moving, through space.
But wait… the Earth also orbits the sun at a specific speed. So, in addition to the angular momentum from the planet’s rotation, you’re also flying through space as the Earth orbits the sun.
Well, is the sun stationary in space? No, not even close! Although all the planets in our solar system orbit the sun, our solar system as a whole actually orbits the Milky Way galaxy. One full revolution around the Milky Way actually takes an astonishing 250 MILLION years to complete!
And what about the Milky Way galaxy itself? Is the galaxy stationary in space? No, it absolutely is not. In fact, there are “galaxy clusters” all over the Universe toward which galaxies tend to move… or cluster.
That’s a rather long way of stating that you are never actually stationary in the scheme of the Universe. From some outside frame of reference, you are constantly accelerating in various “directions”.
So, what the hell does any of that have to do with time at all?
To the Graph!
No, no, we won’t be graphing any type of equation. Rather, we’ll take a quick peek at a spacetime diagram to see what that type of graph can actually tell us.
While “time” is labeled on the X-axis of most graphs you’ll ever use in your life, on a spacetime diagram, “time” is actually labeled on the Y-axis while distance from a source is represented along the X-axis.
What we are seeing here is that for every one unit (seconds) in time (Y-axis), light travels away from the origin by 299,792,458 meters in space (X-axis).
Another way to think of it is, you can pretend you’re standing at the origin of the graph (X=0, Y=0) and trying to measure the speed of the light being emitted from your really powerful laser. As it shows on the graph, for everyone one second in time, the laser light will travel 299,792,458 meters further away from you!
As you can literally see, only the speed of light could be expressed on that graph at a 45 degree angle from the origin. That is the theoretical cosmic speed limit of the Universe! If you could imagine the line plotted for you driving to work, the angle would be much, much shallower than 45 degrees!
Again, what does any of this have to do with time possibly being a “spatial dimension”? We’re getting there, I promise!
With the explanation of the spacetime diagram above, can you guess how the graph would look for an object that is “stationary”?
Well, intuition may tell you that there actually wouldn’t be a line at all, right? If an object isn’t moving through space, then it should be represented by a single point at the origin of the graph, right?
While that does make sense, a stationary object on a spacetime diagram would actually be represented with a perfectly straight, vertical, line from the origin with an angle of 0 degrees.
What that tells us is that even if an object is “stationary” in space, it will always travel through time. Regardless of how still you can be, regardless of what you do, you will always be traveling through time.
But remember, you can never TRULY be stationary in space! For us, the space rock on which we reside is hurdling through space, and of course, through time as well.
That got me thinking… is there some correlation there?
Of course, correlation doesn’t always mean causation, but just stick with me for a minute (pun intended).
I found it quite interesting to know that an object can never ever be truly stationary in space, and as far as we know, an object can never ever remain stationary in time. So, is it possible that the two are one in the same? Is it possible that time, as bizarre as it may sound, is actually the result of our acceleration through the Universe?
So… Could “Time” Be a Fourth Spatial Dimension?
Considering I am not a physicist and this was more of a written thought experiment than anything else, that’s not a question I can answer! But, how exactly could we prove, or better yet, disprove this theory?
For example, if we had the ability to stay perfectly stationary in space with some wild new technology, would time still elapse? Could the astronauts on such a ship experience zero acceleration? And if they could, would they experience the passage of time at all?
Or, what about the “inside” of a black hole? It is hypothesized by some that “time” and “space” essentially swap roles beyond the event horizon of a black hole.
Some folks say it’s because of the extreme warp in spacetime which essentially inverts itself under such astronomical gravitational forces.
But, what if that extreme warping of spacetime could actually cause an object to remain spatially stationary inside the black hole? And sure, you may be thinking that a black hole itself travels through the Universe so there is acceleration, but from inside a black hole, that’s not going to matter. Since time and space are theoretically inverted within a black hole, it wouldn’t really matter what’s happening outside of it, right? It would almost be like existing in a separate Universe.
If that were the case, then the object would be physically incapable of accelerating through space from any frame of reference. And if our experience of time is indeed caused by our acceleration through some spatial dimension, then would it be possible that time would cease to elapse in a black hole for the spatially stationary object?
What the hell would that even mean? If time doesn’t elapse, what exactly is an experience? Would the object be in an eternal still frame? Staring out through the event horizon of a blackhole at the same image until then end of ti…?
Well, that’s my latest thought experiment! I could be way off here, but it would be great if anyone could disprove it. I mean, would it even be theoretically possible to be perfectly stationary in space? If not, then I’m not sure how this could be proven wrong, but I’d love to hear rebuttals (even the nasty ones!).
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So, what do YOU think?
Could “time” potentially be a fourth spatial dimension that we simply cannot detect or measure (we only measure the rate and passage of time) since we are completely immerged in it?
Have you ever considered what would happen if you could be 100% spatially stationary?
