It gets easier year by year. Now we have ion drives. Maybe in 100 years we will stumble upon a breakthrough  technology that allows us to build antimatter rockets: <a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Antimatter_rocket" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Antimatter_rocket</a><p>That would be a direct invitation to other stars in a lifetime.