Recent content by jtaravens

thanks! I managed to figure out that it moves north but I'm glad you added the mid-june thing on top of the equinoxes. Now it makes sense! John

Hi, The reason I'm asking this is because I am planting a shade tree and I want the location to be correct for both early spring and late summer. I am in Maryland (East Coast USA). The sun sets to the west. If I compare the location of the sunset in April to the sunset in September am...

Ok, great! So to apply this to time travel, could one say that if I left Earth in year 2000 and traveled at 80% the speed of light away from Earth for 6 years (according to me) and then (ignoring decelerations and accelerations) traveling 6 years back (according to me), I would return to...

Hello, I was searching online for an equation which would reveal the effects on aging as velocities approach light speed. I found this t = squareroot of (1-(v^2/c^2)) Pardon my math ignorance (I am not a physics student) but when I entered in a velocity of 80% the speed of light the...

Thanks guys. I printed out some stuff on spacetime diagrams. I'll try to apply what I learn to my above stated problem. John

Are you saying that the 150 year difference in "now" doesn't really happen? What do you mean by “nothing physical?” I'm still pretty confused. I was thinking along the lines of typical time dilation effects where motion is going to make people age differently - I assumed that the aging...

Slicing the spacetime "loaf" I’m having a little trouble understanding an analogy in Greene’s “Fabric of the Cosmos.” I would be grateful for any attempts to explain this or to point me to some examples on the web. I’m reading about spacetime and the Greene equates spacetime with a loaf...

Well that confuses me a bit - why would the barn's rest frame mean that the back door must close later than the front? While the runner is in the barn, couldn't the back door close before the front door? I believe my question wasn't so clear. (but no need for mathematics - I'm only a...

As I was reading Fabric of the Cosmos, I got stumped at the relativity of simultaneity section. This led me to Google for some additional explanation. I stumbled upon http://www.phys.unsw.edu.au/einsteinlight/jw/module4_pole_paradox.htm" which made me think of this question regarding the pole...