A - defining velocity through spacetime
There is a constant in nature, called C.
C is the speed at which anything moves through spacetime.
As predicted by Einstein and confirmed by experiments:
- A stationary massive object moves 100% of C through time and doesn't experience movement.
- A photon moves 100% of C through space and doesn't experience time.
- Anything else lies between these two extremes
Total spacetime velocity = [speed through time]^2 + [speed through space]^2
If we chart this "function", we get a circle as a result. Since the radius of a circle is always the same, we see that velocity through space-time is always C. This explains why moving faster slows time, it's because you cannot move faster than C through space-time. Faster spacial velocity necessarily slows time-velocity. The extreme endpoint is a photon (or anything massless), which doesn't move through time at all. Conversely, it explains why a motionless object experiences time quicker. Afterall, if an object doesn't move then it must move 100% of it's C velocity through time. All of these predictions of treating C as the constant space-time velocity fit the predictions of Einstein as well as experiments.
CONCLUSION: C is the universal constant of speed. Nothing moves slower, nothing moves faster, all things move at C through space-time.
B - defining space
Space should be pretty straightforward. Space is simple to understand. Speed through space is to change your position.
C - defining time
Time has no definitive conclusions. Time is relative, it depends on the spatial velocity of an object. Why is that?
Solution 1: Say that time is a magical/unseeable dimension that alters our 3d space
Solution 2: Say that time is "the rate of interaction" in the universe
Solution 3: Unknown (at least to me)
I want to make a solid argument for the second one. Time = the rate of interaction. (Interaction is when to objects have an impact on each other. )
The fastest possible way to interact is to send a photon. A photon uses 100% of it's C velocity through space, and doesn't experience any time-delay.
Imagine two stationary objects, both moving 0% of C through space. This means that a signal photon sent from A to B is the fastest interaction possible.
[A] -----------------------------===>[B]
A and B are both having a velocity through time of 100% of C, as predicted by Einstein. According to this model, they do in fact have a rate of interaction off 100%, since there is no conceivable way for them to interact quicker. But what if A and B were in motion? Well, it's velocity through space would increase, and it would move slower through time. What happens in our experiment?
[A]----------------------===>----------[B]
[A]----------------------------------===>[B]
Excactly what you would expect. B is moving away from the incoming photon, which means that an interaction from A to B via the photon is slower. No matter how fast A moves, the photons hitting B move at the speed of light. However, if the photon is reflected back at A, it would move much faster. In the end, the total "slowing of time" in the system AB is really not that noticeable. This fits our experiments with atomic watches in orbit around earth.
However, what if we let object AB move at 90% the speed of light.
- Interaction A=>B will take 10 times as long
- Interaction B=> will take 0.52 times as long
- In total, each interaction will last more than 5 times longer
- AKA: it would move through time 5 times slower
In other words, when an object like AB is approaching lightspeed, it starts to interact very slowly.
And guess what Einstein said about high speed? Answer: that time would start getting very slowly.
Anything moving at the speed of light cannot accelerate any further since acceleration requires interaction.
Massive objects can never achieve C, because no matter how much energy you put into it, time will slow down exponentially. When your last photon is fired in order to accelerate your particle into lightspeed, it will take near infinite "time" for the photon to reach our particle. From the perspective of the particle though, time is moving so slowly that it just feels like a moment. Acording to Einstein, moving at C destroys time. This is exactly what this model explains.
CONLUSION:
Time is how fast objects interact, which depends on how fast photons can make them interact, which depends on the velocity of the objects that experience time.
The correlation between spacial C and time C is that the spacial C creates time C.
This explains why a simple particle moves at 100% spacial C, while only complex systems of interaction have mass and "temporal" velocity.
In fact, C's "rate of movement" might be the actual definition of time we are searching for.
The funny part is that this model explains how an objective value "C" is needed for there to be a relative value "time.
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