Ok, so you think I am just going to write fiction on this blog?
Interestingly, the following might sound more like fiction than what really is. You tell me...
Everyone knows, or at least I hope, that the speed of light in a vacuum is constant. We give its speed a special name: "c". Yes, the same c from Einstein's famous equation, E=mc^2.
Interestingly, the following might sound more like fiction than what really is. You tell me...
Everyone knows, or at least I hope, that the speed of light in a vacuum is constant. We give its speed a special name: "c". Yes, the same c from Einstein's famous equation, E=mc^2.
Side note: For those like myself who have impaired html abilities, the "^" denotes squared.
To remove any math, let me draw a simple analogy. Imagine a compass, with just the North South line, and perpendicular East West line. Traveling North represents you moving through time. West is you moving through space. Normally, we think that moving through time (North) is a constant. Watches tick regularly, etc. But when you move through space (West) relative to an observer, it turns out that you actually slow down your progress through time. The effect is small for any speed you and I can easily achieve, but if you could travel the actual speed of light, time would literally stop! Per the analogy - you have changed your compass heading.
But here is the tricky part - you have NOT modified your overall speed. The combined speed in space-time is still the speed of light! Just like the compass needle, your speed did not get longer or shorter, it just turned a little off the its original Northerly heading.
So far, if you don't start asking some questions, this just seems like one more useless thought experiment. So...
If we are fairly stationary in space, are we saying that we are still moving at the speed of light? The curious answer is YES. We move though the time dimension at the speed of light! When we get into the Starship enterprise and start moving at sci-fi speeds approaching that of light, we are just borrowing from our speed in time (time slows down) and replacing it with speed through space. So don't let anyone tell you that you can't move at the speed of light. You are REQUIRED to travel at the speed of light at all times. Any actual speed we gather in the spatial dimensions is achieved at the expense of borrowing from our progess through time!
Ok, then what about light itself? Didn't we just say that the speed of light is a constant "c"? And isn't this speed measured exclusively in the spatial dimension? Indeed. Light's heading per our analogy is Westward only. No motion at all in the Northerly direction. But... North, that is the passage of time isn't it? What does that mean for the poor photon, which is really all light is? It means that all light lives in a timeless world. Time can never progress for a photon. Unlike us, who can choose by some investment of energy to participate in both spatial and temporal dimensions, photons are captives of a single time point.
As if THAT isn't stranger than fiction...
To remove any math, let me draw a simple analogy. Imagine a compass, with just the North South line, and perpendicular East West line. Traveling North represents you moving through time. West is you moving through space. Normally, we think that moving through time (North) is a constant. Watches tick regularly, etc. But when you move through space (West) relative to an observer, it turns out that you actually slow down your progress through time. The effect is small for any speed you and I can easily achieve, but if you could travel the actual speed of light, time would literally stop! Per the analogy - you have changed your compass heading.
But here is the tricky part - you have NOT modified your overall speed. The combined speed in space-time is still the speed of light! Just like the compass needle, your speed did not get longer or shorter, it just turned a little off the its original Northerly heading.
So far, if you don't start asking some questions, this just seems like one more useless thought experiment. So...
If we are fairly stationary in space, are we saying that we are still moving at the speed of light? The curious answer is YES. We move though the time dimension at the speed of light! When we get into the Starship enterprise and start moving at sci-fi speeds approaching that of light, we are just borrowing from our speed in time (time slows down) and replacing it with speed through space. So don't let anyone tell you that you can't move at the speed of light. You are REQUIRED to travel at the speed of light at all times. Any actual speed we gather in the spatial dimensions is achieved at the expense of borrowing from our progess through time!
Ok, then what about light itself? Didn't we just say that the speed of light is a constant "c"? And isn't this speed measured exclusively in the spatial dimension? Indeed. Light's heading per our analogy is Westward only. No motion at all in the Northerly direction. But... North, that is the passage of time isn't it? What does that mean for the poor photon, which is really all light is? It means that all light lives in a timeless world. Time can never progress for a photon. Unlike us, who can choose by some investment of energy to participate in both spatial and temporal dimensions, photons are captives of a single time point.
As if THAT isn't stranger than fiction...
PS - anyone worth their physics salt will point out all the errors I made here. Chill... I know where I took corners to tell an unencumbered story! :-)
4 comments:
Hi Love. I really wish I could be like, "oh yes, of course. I completely agree, but what if you take into consideration ____?" But you know that the only thing i think when you talk like this is how sexy smart you are. :-) Keep it coming. Someone else will totally get it.
It's about as clear as any other science explanations. I had never heard of light stuck in some timeless place.
I'm sure you have read about experiments ( successful) to slow down light. What happens to the photons then ?
Yes, I have heard of those experiments. You can find out more following the link http://www.physlink.com/Education/AskExperts/ae509.cfm.
What it states is that "When light enters a material, photons are absorbed by the atoms in that material, increasing the energy of the atom. The atom will then lose energy after some tiny fraction of time, emitting a photon in the process. This photon, which is identical to the first, travels at the speed of light until it is absorbed by another atom and the process repeats. The delay between the time that the atom absorbs the photon and the excited atom releases as photon causes it to appear that light is slowing down."
Hope that helps clear things up!
I see. Now I get it. Clear as....
as.... ______ ( Fill in the blank)
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