Recent content by dagmar

And what do you think you're doing by using Rindler worldlines to describe motion in an everywhere perfectly uniform grav. field like that of the elevator example in question?? No, everywhere at each point around your elevator thought experiment, acceleration stays the same in magnitude and...

Good. Be happy. Your analysis is irrelevant to me and to anyone who understands Physics for that matter. If you believe that the spacetime direction of the 4-acceleration vector matters it is your problem. If you believe that the orientation of the walls of an elevator in regard to the...

They're equal..It's not a Rindler universe. Constant acceleration everywhere we said. Excuse me now, but I don't have time to read your last messages. I have a marathon to run and you've kept me awake last night. In the meantime re-think your examples and don't be so rash.

Oh , yes please do so, for the elevator example that you have given us and please announce the results!

Ok, draw your diagrams. What you get is an hyperbola in the t-x plane for the stationary observer and another one in 3D space not belonging in any of the t-x, t-y or x-y planes. Uniform acceleration didn't you say? Right, now measure the radius of curvature of your two hyperbolas and find them...

If your destination is the North or South Pole you can more or less get there, if it is another place you certainly need more information. Nevertheless, there are names of villages in the map, rivers, mountains which if you can identify you can navigate.

Ok, I misinterpreted your example. Just remember that in case Superman flies along the radius of planet at constant speed there is no difference in elongation of string.

Perpendicular to the planet's acceleration, hence tangentially to the surface of the planet... As measured by each in his FOR (frame of reference) right?

@Idunno Well do tell us, which scenario do you imply? Please read the answers carefully this time.

@pervect Huh? What's this all about? I was referring to your #12 post. The direction of motion of the second elevator is at right angles with its flat floor, and both floors of the elevators are parallel to each other. It's shooting upwards the surface of an imaginary planet past a stationary...

Since when, and in what possible way the phenomena observed in a closed elevator that undergoes constant acceleration g with initial velocity=0, will be any different than those in another elevator that begins to accelerate constantly ( same g ) with initial velocity v=velocity of Superman...

"The problems of Philosophy" by Bertrand Russell is a good one. When I was a first-year Pure Maths undergraduate in the UK back in 1986, I took a course in Philosophy for scientists and this book was recommended by the professors for the course. It's a nice little book and very easy to read.

Hmmm, the M_Discs will last 1,000 years ( I do not believe it! ) but how long do you think DVDRW drives will last? Floppy disk drives are now obsolete and so are tape recorders. This article might be of interest: http://advances.sciencemag.org/content/2/10/e1600911.full Optical microscopes will...

Storia delle Matematiche by the old Professor Gino Benedetto Loria (Mantova, 19 May 1862 – Genova, 30 January 1954).

Both distances (1) and (2) are invariant under Lorentz transformations to be defined as Hyperbolic rotations of the Minkowski plane in the (1) case and ordinary rotations of the Euclidean plane in the (2) case. As I've already explained to you in #6 post the (1) case yields invariant speed of...