3 ms·

To clarify the physics here a little: The constant speed is actually the speed of a massless object through spacetime. It just so happens to be that photons ha

To clarify the physics here a little: The constant speed is actually the speed of a massless object through spacetime. It just so happens to be that photons have no mass. Also, going at high speed wouldn't make your life pass in slow motion to you. It would simply look that way to an observer who was moving vastly slower than you. The dilation in time is as a result of difference in relative velocities, rather than the speed of time changing. This is also why the part about "go faster than the speed of light" doesn't make sense in physics. Motion is a four dimensional vector, with three points giving a point position, and the forth giving velocity through spacetime. Thus you wouldn't be travelling through "time" backwards, but through spacetime backwards. Hope that helps. For more information, you may want to read up on the geometry of Minkowski spacetime.

scarygliders 10y ago
In a reply I also just made alongside yours, I mention that we're actually measuring the speed of causality - so you could think of "the speed of a massless object through spacetime" as the "speed of causality".
- petewailes 10y ago
  To be pernickety (because we like that around here), what I think you're referring to is the transmission of information, which is still down to the maximum velocity at which something of no mass can propagate through spacetime to interact with something else within its light cone[0][1]. The important thing in causality is the concept of the light cone. For things that happen far apart enough that the light cones don't interfere with each other, causality doesn't matter. One could happen first, or the other. It's only when you consider two things where the interaction occurs that the propagation matters. Clearing this up a little further, having just read your other comment, the causal link between events and the speed by which information propagates is as a result of c, not the cause of it. 0: https://www.wikiwand.com/en/Light_cone https://www.wikiwand.com/en/Light_cone 1: http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/spacetime/ http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/spa...

scarygliders 10y ago

In a reply I also just made alongside yours, I mention that we're actually measuring the speed of causality - so you could think of "the speed of a massless object through spacetime" as the "speed of causality".

petewailes 10y ago
To be pernickety (because we like that around here), what I think you're referring to is the transmission of information, which is still down to the maximum velocity at which something of no mass can propagate through spacetime to interact with something else within its light cone[0][1]. The important thing in causality is the concept of the light cone. For things that happen far apart enough that the light cones don't interfere with each other, causality doesn't matter. One could happen first, or the other. It's only when you consider two things where the interaction occurs that the propagation matters. Clearing this up a little further, having just read your other comment, the causal link between events and the speed by which information propagates is as a result of c, not the cause of it. 0: https://www.wikiwand.com/en/Light_cone https://www.wikiwand.com/en/Light_cone 1: http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/spacetime/ http://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/spa...