Recent content by consal

I was under the impression that's the sort of stuff journalists ask all the time. And they get answers. Wrong answers, but answers anyways. D: Well, fair enough. These are the physics forums, not the "dumbed-down physics" forums. The reason why I'm asking is because a friend asked me what...

No, I got that. I was not asking if instantaneous communication was possible. I was just wondering what the ramifications of it would be. I also received the impression that it might have been a "meaningless question" in the sense that there is no meaning for the word "instantaneous" in where...

I have incoherent moments. But that's what I meant. Just wanted confirmation. Thanks!

The "message" travels back in time, am I correct? Because event propagation is at the speed of light, but the message is instantaneous, so at the frame it arrives it has traveled back in time...

Thanks again.

Oh right. Thanks! edit Wait, there is no massless particle that has time-like intervals?

Well, yes, I'm mainly asking why a system of one massless particle cannot have a center of momentum frame if it has relativistic mass. What is inherent about invariable mass that it precludes the ability to have a center of momentum frame whereas relativistic mass cannot?

As the title. More specifically, with respect to the center of momentum frames massless particles don't have, why not if they still do have relativistic mass? (Bracing for an easy answer to a stupid question...) :redface: