I would like to enter my submission . Behanced portfolio <| sep |> Looking forward to another weekend full of rage and disappointment thanks to Fifa . Anyone else playing the Weekend League ? <| sep |> Sadly don ' t look at a S 820 base android phone . They lag . Unless you want to IOS I would just stick with the Nexus 6 and wait for next snapdragon chipset . <| sep |> You can actually do the calculation for the twin paradox in SR no problem by considering the astronaut as moving through a series of infinitesimal inertial frames . Acceleration of the astronaut is not required , it is then down to the difference in length of the timelike curves that explains the age difference . The reason that this is preferable is because it is possible to come up with a version of the twin ' s paradox that does not contain any acceleration and instead involves a set of twin ' s that follow two geodesics in curved space that end up taking them along different paths and reuniting at a later time . It is pretty hard to explain in full but a hint towards the right direction is to imagine the Earth bound twin sending a video message by radio to the astronaut twin every year on the same day , perhaps their birthday . Since the twin ages each time between messages he can use these to track the earth twin ' s age . In the frame of the Earth twin the messages will not reach the astronaut once a year because each year the distance the message has to travel has grown larger so the frequency of the messages arriving is slower than that of sending . After the turn around the messages will be arriving at faster than 1 a year since now he is shrinking the distance between the two observers . What is important is that turn around moment , wikipedia has a good visualisation of t h i s T w inParadoxMinkowskiDiagram . svg . png . What you are looking at is slices of simultaneity in spacetime , the slope of these is a reflection of the velocity if the twins . While outbound the astronaut thinks that the events connected by the blue lines are simultaneous and while inbound he now thinks those that are connected by the red line are simultaneous . When he makes that turn he has to transition between the final blue point and the first red point . Hopefully you can see that the difference between those two points is large , this is the change in age of the Earth twin that the astronaut twin thinks happens during his turn around , no need to invoke anything other than the two frames of constant velocity as no matter how fast he does the turn around we know he makes the transition from blue lines of simultaneity and red lines , therefore possible to do the math in SR .