Is it ever going to possible for humanity to pass the border of our galaxy?
If you peer out into the depths of space -- at the vast expanse of stars, galaxies, and even the leftover glow from the Big Bang itself -- you might think that if humanity can understand the laws of nature and create a good enough technology, there are no limits to what we can explore. If we were to develop nuclear fusion technology, antimatter storage capabilities, or even the ability to harness dark matter as we traveled, we could unlock the potential for interplanetary, interstellar or even intergalactic travel. By accelerating ourselves over months or even years to reach near-light speeds, we could even reach our target destination within a single human lifetime.
Yet even if we imagine a future where we can do exactly that, there are still parts of the Universe that will be forever inaccessible to us. If the Universe were static, constant and forever unchanging, then all it would take was time to reach even the most distant object we could fathom. But our Universe isn't any of those things; it's expanding, cooling, and gravitating from an initially hot, dense state known as the Big Bang.
Exploration beyond the limits of the Solar System is already a reality. The American probes Voyager 1 and 2, launched more than 40 years ago, are entering interstellar space (the status can be checked at this link). However, they will not cross with other stars. The Starshot proposal, by breakthrough initiatives, is aimed at sending thousands of nano crafts to start exploring the closest stellar systems, which would be the first step in a colonization process.
However, spreading out within the Solar System or even interstellar for overpopulation due to the billions of human beings inhabiting our planet or the overexploitation of resources, given that, if technically possible, . Thus, the impact of such a process would be entirely excessive and the negative consequences are likely to far exceed any possible advantages.