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The following questions (in no particular order) which I had submitted have been "Deleted by Community":

2. Is average speed an invariant?

Is the value of average speed an invariant?,
specificly the value of the average speed, with respect to suitable(1) specific participants, say $P$ and $Q$, of some specific participant, say $A$, as $A$ moved from $P$ and $Q$?

Expressing the value of the average speed of $A$ wrt. $P$ and $Q$ as

$$v_{PQ}[~A~] := c~\beta_{PQ}[~A~],$$

where $c$ denotes the signal front speed, and $\beta_{PQ}[~A~]$ is a specific real number,
and where the average refers to the trial from $P$ and $A$ having departed from each other until $P$ and $A$ having reached each other,
does the value of $\beta_{PQ}[~A~]$ depend on the assignment of coordinate values to the relevant unique events $\varepsilon_{AP}$ and $\varepsilon_{AQ}$ (and/or to other events)?

Does the real-number value $\beta_{PQ}[~A~]$ change if coordinate values which are assigned to event $\varepsilon_{AP}$ are being changed, or if coordinate values which are assigned to event $\varepsilon_{AQ}$ are being changed?

Note also, that the real-number value $\beta_{PQ}[~A~]$ can be expressed in terms of intervals "between" certain pairs of the relevant events, e.g.

$$\beta_{PQ}[~A~] = \frac{s^2[~\varepsilon_{AP}, \varepsilon_{AQ}~] - s^2[~\varepsilon_{FQ}, \varepsilon_{AQ}~]}{s^2[~\varepsilon_{AP}, \varepsilon_{AQ}~] + s^2[~\varepsilon_{FQ}, \varepsilon_{AQ}~]},$$

where event $\varepsilon_{FQ}$ denotes the (unique) event of the future ("forward") light cone of event $\varepsilon_{AP}$ in which $Q$ took part (in coincidence with some suitable participant $F$); and that (presumably) the values of intervals are invariant.

(1: Specifily, $P$ and $Q$ remaining separate and at rest with respect to each other; i.e. constituting members of an inertial system in the sense of Rindler: "simply an infinite set of point particles sitting still in space relative to each other".)


1d
revised Angle sum of triangle in Schwarzschild solution
corrected spelling the name of K. Schwarzschild (also in the title);cmp. https://en.wikipedia.org/w/index.php?title=Schwarzschild_Solution
Jul
27
revised How to derive the Schwarzschild metric?
corrected spelling the name of K. Schwarzschild; cmp. https://en.wikipedia.org/wiki/Schwarzschild_metric
Jul
27
revised Schwarzschild Solution
corrected spelling the name of K. Schwarzschild (in the title); cmp. https://en.wikipedia.org/wiki/Schwarzschild_metric
Jul
27
revised Curvature based derivation of Schwarzschild Metric
corrected spelling the name of K. Schwarzschild; cmp. the link which was already present in the OP
Jul
27
revised Is momentum an invariant?
(v3.1: referring specificly to the sense of the word "invariant" as used in the theory of relativity.)
Jul
27
revised Is momentum an invariant?
(v3.14159: capitalization still matters!)
Jul
24
revised Angle between two momenta in particle physics (principal axis of a two-body decay vs. center-of-mass motion in the lab)
suggested an expansion of the title to make it more descriptive and specific. Also: some gentle copy-editing
Jul
24
revised Angle between two momenta in particle physics (principal axis of a two-body decay vs. center-of-mass motion in the lab)
(v3.14159265: a bit neater, still ...)
Jul
23
revised Angle between two momenta in particle physics (principal axis of a two-body decay vs. center-of-mass motion in the lab)
(v3.1415926: matching squares, instead of square root)
Jul
23
revised Angle between two momenta in particle physics (principal axis of a two-body decay vs. center-of-mass motion in the lab)
(v3.141592: replaced incorrect dot multiplication by plain scalar multiplication; rearranging terms suitably. Also some additional formatting.)
Jul
23
revised Angle between two momenta in particle physics (principal axis of a two-body decay vs. center-of-mass motion in the lab)
(v3.14159: copy-editing.)
Jul
23
revised How to achieve vertical lift using magnets
title modified; copy editing
Jul
16
revised Why do we use Mie scattering to describe light scattering off large objects?
spelling corrected
Jul
9
revised Two apparent contradictions in SR involving time dilation and length contraction
(v3.1415: more copy-editing)
Jul
9
revised Two apparent contradictions in SR involving time dilation and length contraction
(v3.141: corrected/inverted duration ratio; and some copy-editing)
Jul
4
revised Simple Harmonic Motion in Special Relativity
(v3.141592: mistaken minus-sign removed.)
Jul
3
revised Must the product of the two complementary quantities in an uncertainty relation have unit $\text{Js}$?
Expressed the Uncertainty Principle (also) as **in**equality; and corrected spelling the surname of M. Planck.
Jul
3
revised Must the product of the two complementary quantities in an uncertainty relation have unit $\text{Js}$?
corrected an omission (exponent) and minor spelling
Jul
2
revised Accuracy and Error of Atomic Clocks
some corrections and copy-editing
Jun
30
revised Why are neutrino and antineutrino cross sections different?
Corrected spelling the surname of N. Cabibbo; together with some minor copy-editing to reach the required change of at least six characters.