Comic Genesis Forums

yep, the whole spacechip blasting the meteor scenario

BlasTech wrote: meaning at some point in time (in more hitchiker terms) some schmuck is going to figure out a way to supercharge his little spaceship and then collapse us all the way back to the beginning of time again :D

All the more reason to just make an improbability drive, and just skip all that mucking around with lightspeed vehicles and whatnot.

Kerry Skydancer wrote: High school chemistry pretty much teaches that mass is constant.

Okay, yep. That last good science class was high school chemistry.

Kerry Skydancer wrote:In the more precise versions of chemistry and physics, however, mass-energy is the conserved quantity...

Okay, that makes sense. I can see it now.

Kerry Skydancer wrote:Now if you want things to get really weird, you have to start taking the changes in perceived duration into account under intense gravitational fields (aka intensely deformed spacetime) or high relative speeds. This can even lead different observers (which means observers moving at different velocities) to disagree on the order of observed events.

Hmmmm... I think the forums are weird enough for me.
No, actually, that's intriguing... but way over my head. (Last good science class being high school chemistry and all. )

Thanks for the explanation.

Just gotta love relativity. Umm, ill try to recount an example of this Wayfarer lemme see if i can remember how it went:

the main part of relativity comes from the statement that the speed of light is constant in all frames of reference. that means that if i see light, it moves at the speed of light no matter how fast i am moving myself.

Imagine a train moving at relativistic speeds (say ... 0.8C), there's a guard at one end, and the driver at the other. in the middle, there is someone with a lamp. when the driver or the guard sees the lamp turn on, they wave at the lampholder.

-= In the frame of reference of the lampholder.=-

He turns on the lamp, light goes out at C and the driver and guard see it simultaniously, they both wave at the same time, and he sees them wave at the same time.

-= In the frame of reference of a person standing by the side of the rail as the train goes past =-

He sees the light turn on, but he sees the light move at C while the train moves in one direction at 0.8C. As a result he sees the light "racing" with the train. To him, it would seem as if the guard at the end sees the light first and waves first and that the driver sees it later and waves second.

Finally, put all these people in a room together and ask the question "who waved first" and you'll get some interesting answers.

The comment about light exceeding its own speed limit is actually a very valid one. The maximum speed for anything that we know of is the speed of light in space, which is termed C. However, when traveling through a medium other than space light moves considerably slower. Objects can exceed the speed of light in a medium other than a vaccume, resulting in Cerenov radiation (no clue if I'm spelling that right). That's actually the basis on which most neutrino detectors are built... detecing those blue flashes of Cerenov radiation can allow you to narrow down roughly where a neutrino was coming from, as the light expands out in a cone pointing in the direction that the particle was going... similar to how a sonic boom travels the same direction as the plane that made it.