<story><title>Why can’t I go faster than the speed of light?</title><url>https://gravityandlevity.wordpress.com/2009/04/08/why-cant-i-go-faster-than-the-speed-of-light-hints-from-electrodynamics/</url></story><parent_chain><item><author>redwood</author><text>I think a lot of people assume that this means you couldn&amp;#x27;t go more than a few (~100) light-years in your lifetime... But this is not actually correct. Counter-intuitively you can theorically go any number of light-years (essentially) in your lifetime, as long as you are able to approach the speed of light because when you do so the distance is dilated and hence you&amp;#x27;re covering far more ground within your reference frame (of course you&amp;#x27;d be in the deep future from the perspective of anyone in our normal reference frame).</text></item></parent_chain><comment><author>nostromo</author><text>You can even do so without going near the speed of light if you build a very massive ship and utilize time dilation of gravity.&lt;p&gt;Arvin Ash has a cool video on this that is probably too complicated to describe in a HN comment:&lt;p&gt;&lt;a href=&quot;https:&amp;#x2F;&amp;#x2F;www.youtube.com&amp;#x2F;watch?v=PA66ah9b0U4&quot; rel=&quot;nofollow&quot;&gt;https:&amp;#x2F;&amp;#x2F;www.youtube.com&amp;#x2F;watch?v=PA66ah9b0U4&lt;/a&gt;</text></comment>
<story><title>Why can’t I go faster than the speed of light?</title><url>https://gravityandlevity.wordpress.com/2009/04/08/why-cant-i-go-faster-than-the-speed-of-light-hints-from-electrodynamics/</url></story><parent_chain><item><author>redwood</author><text>I think a lot of people assume that this means you couldn&amp;#x27;t go more than a few (~100) light-years in your lifetime... But this is not actually correct. Counter-intuitively you can theorically go any number of light-years (essentially) in your lifetime, as long as you are able to approach the speed of light because when you do so the distance is dilated and hence you&amp;#x27;re covering far more ground within your reference frame (of course you&amp;#x27;d be in the deep future from the perspective of anyone in our normal reference frame).</text></item></parent_chain><comment><author>wruza</author><text>Also, it doesn’t take too much acceleration to make that trip. Comfortable earthlike 1g (~ 10m&amp;#x2F;s&amp;#x2F;s) is enough to build up a decent speed in a very reasonable time. Energy is the issue though.</text></comment>