ufology
Master Poster
- Joined
- Jun 30, 2011
- Messages
- 2,681
The physics indicates it would take an infinite amount of energy to accelerate even a single massive particle to the speed of light, and that's why only massless particles can travel at that speed. So lightspeed travel is out of the question, according to the science.
Acceleration is the rate of increase in an object's velocity. That depends on its linear momentum (its mass multiplied by its velocity), the amount of force applied to increase that momentum, and the amount of time that the given amount of force would require to increase that momentum by a given amount.
Without getting into the specific math, Newtonian physics also proves that the faster an object is already traveling, the more force and/or time it requires to accelerate it even faster; as it accelerates, a constant amount of force will have diminishing returns toward accelerating it faster over time, and constant acceleration requires an increase in force over time. Then you've got to factor in relativistic physics, which indicates that the object's mass actually increases as it approaches c (at which point it would theoretically have infinite mass). I haven't actually crunched the numbers, but suffice to say that accelerating a macro-scale object like a spacecraft up to near the speed of light ends up being a balance somewhere in the middle between astronomical energy levels and cosmic time frames.
Then you've got to factor in the g forces of acceleration and those effects on the structure of the craft and its passengers.
And don't forget, once you've accelerated to that near-light speed, then you've got to be able to decelerate as you approach your destination, which in a vacuum would require just as much energy as it did to accelerate in the first place.
Sure, with what we know now, lightspeed travel is not possible. However the flaw in this argument with respect to interstellar travel is that it assumes we need lightspeed travel to accomplish the task. Really, all we need is enough time and a decent ship.
The other thing is that we can safely assume that even though we don't have adequate technology now, providing our species and its technology continues to survive and evolve, we will have sufficient technology in the future, and given the rate our technology is currently evolving, a century or two should be about all that it takes. By then our own science will likely have solved both energy and aging problems, if not many more.