@Brandon9000,
The source is myself applying my understanding of relativity which is amateurish..nonetheless you just need to know 2 or 3 things to apply the principle. It easy to grasp. You know as everybody knows that at speed of light time goes faster and you know the speed is relative among observers. You also know that at a tenth of speed of light time dilation is a tenth of what would be if you were going at the speed of light right ?
Now take that into smaller and smaller and smaller fractions of speed of light...say instead of a 10th a 100th, or a 1000th, or 1 million under...in all scenarios you have ever smaller time fluctuations up to the point they barely can be noticeable unless you use an atomic clock (which we do in GPS satellites so they are precise, its not just maths and sci-fi its a scientific proven and tested fact)...what this means in turn is that no matter how small the change in speed is, there will always be ad infinitum a very very very small time dilation and that no one no thing lives/exists exactly in the same spacetime frame in relation to anything else. This of course has also repercussions in Quantum mechanics...explaining them is often left behind and set apart mainly because Einstein well established model theory of relativity regarding gravity and macroscopic things doesn't cope well with quantum mechanics models which explain the microscopic particles, the math of both works, but doesn't get along with each other...this is why searching for a theory of everything that unifies the motions and processes of all 4 fundamental forces of nature, gravity, electromagnetism, strong and weak nuclear forces has been a extremely hard task no one has accomplished in the past 100 years in physics...the closest we got was with Steven Hawking black hole radiation that established a connection between gravity in black holes and virtual pairs of particles governed by quantum mechanics proving even black holes can lose mass through energy when these pairs are freed from annihilating each other in the event horizon of a black hole, it got its creator name Hawking radiation... and it grant him Newtons chair in Cambridge and world wild prestige. More recently we have other candidates like super string theory with several variations on the matter.