Why is direction irrelevant when it comes to approaching the speed of light? I speak of the curious effects that follow (time dilation, swell in mass, etc) Intuition tells me that the big bang happened at a single point, therefore it's only logical to travel in the direction of that point if one were to travel back in time. ...not true. It is wrong to model the big bang this way. Expansion is better explained using a balloon. Still isn't clear though.