The discussion centers on the concept of the speed of light as a universal limit and the implications of objects moving at or near this speed. Participants explore the nature of relative velocity in the context of special relativity, the effects of acceleration, and the potential for faster-than-light travel, including its theoretical consequences on causality and time travel.
The discussion contains multiple competing views regarding the nature of relative velocity and the implications of traveling at or near the speed of light. No consensus is reached on the interpretation of these concepts.
Participants reference various sources and examples to support their claims, indicating a reliance on specific definitions and interpretations of relativistic physics. Some statements reflect assumptions about the nature of time and causality that remain unresolved.
Cyclopsicle said:what if two objects are moving towards each other at more than half c, in reference to a body at rest, wouldn't the objects be traveling more than the speed of light in reference to each other?
HallsofIvy said:... if you observe two objects moving directly toward you ...
Most of the answers were probably given quite recently on this forum, for example here:Cyclopsicle said:I'm confused on how it would be impossible to be faster then light, is it your acceleration? or is it how fast you are going in comparison to some other frame of reference (I do see that phrase being thrown around here)? Because if 2 objects are moving towards each other at more than half the speed of light, doesn't it mean that in respect to each other it is moving faster then c?
Actually, in order not to worry about angles, I was thinking of the situation in which "you" are standing directly between two objects, each moving toward "you" with speed, relative to "you", of .6c.phinds said:Halls clearly meant towards EACH OTHER
Yes, according to FICTION like Red Dwarf that is exactly what happens. Different fiction authors may do it differently.EBENEZR said:If, for whatever reason, you traveled faster than the speed of light relative to another individual, would you not merely experience situations before the other individual has had a chance to catch up? Much like that early episode of Red Dwarf, you wouldn't be traveling back in time, but in fact in front of other people's time?
Time: https://www.physicsforums.com/showthread.php?t=643834EBENEZR said:[..] For that matter, does the fact light is limited to a certain velocity, time travels at a particular velocity also? Time is not in fact instantaneous, rather time travels at ~299x10^6m/s?
The problem is that you are effectively saying "If relativity we not true, what would relativity say about this situation?" If relativity is not true (if you CAN travel faster than light), then relativity wouldn't say anything about! You have to fall back to Newtonian physics which says that it is possible to travel faster than light but nothing can travel back in time.EBENEZR said:If, for whatever reason, you traveled faster than the speed of light relative to another individual
, would you not merely experience situations before the other individual has had a chance to catch up? Much like that early episode of Red Dwarf, you wouldn't be traveling back in time, but in fact in front of other people's time?
For that matter, does the fact light is limited to a certain velocity, time travels at a particular velocity also? Time is not in fact instantaneous, rather time travels at ~299x10^6m/s?