Recent content by Thytanium

Thanks you friend Orodruin. Thanhs you very much.

Good morning friends of the Forum. For me it is difficult to geometrically imagine a tensor of order 2 and maybe that is why it is difficult for me to know, what remains invariant when making a change of coordinates of this tensor. The only thing I can think of it, is that since a tensor of...

Hello PF friends. Hello friend Dale. Studying the metric that you propose friend Dale based on the gravitational potential in the coordinate system "t,x,y,z" and trying to solve them for "z", and for movement only in the coordinate "z" that is to say ##\ddot t_\tau = dx =dy = 0## and considering...

Thanks friend Pervect. Very good explanation. Thanks for your answer. I am studying these answers to try to understand them. Good day.

Hello friend Ibix. I really appreciate your answer. The "t" coordinate is really "ct" right? so it must be ##c.dt/d\tau = c##. Thanks friend Ibix.

Friend Dale if you can explain the equation ##\Phi = gz## to me that is very simple I appreciate it.

Hello friend Dale. Very good answer. Where you locate the origin of the coordinate system txyz to use ##\Phi = gz## so that in the vicinity of the earth's surface ##\Phi = g##. Forgive me friend but I don't understand that equation. Thanks my friend.

Hello friends of the Forum. I want to ask you why the inertial acceleration in free fall in the relativistic geodesic equations is assumed equal to zero in free fall and equal to 9.8 m/s at rest on the earth's surface. On the other hand, assuming that zero acceleration in free fall, what would...

Welcome anémone. Thank you for being here collaborating with PF. Very grateful for your presence.

Yes I can. It's simple. If I have two vectors A and B and do the inner product A.B, to prove bilinearity first with vector A, I do (kA).B where k is a scalar. So that's equal to k(A.B) = kA.B and then with vector B it's the same procedure so the inner product of two vectors is doubly linear. And...

Wonderful clarification fresh_42. Very grateful to you friend.

Thanks you my friend Orodruin. Happy Day.

Thank you Orodruin for your PF Insights and especially for The Birth of a Textbook. Little by little I will read them. They are very interesting. Thank you friend.

Thank you Orodruin for this interesting information. I did not know that the sum was not linear in his arguments. That is very interesting. But I don't understand why if the sum were linear in the first argument it would produce ##a_1 + a_2 + 2b## and excuse my ignorance. Thanks again my friend...

:biggrin::biggrin: