Recent content by Incnis Mrsi

Is the lunar day–night period “28 Earth days”, is it really that short? I expected it to be exactly equal to the Earth–Moon–Sun synodic period (29½ days) because Moon is tidally locked to Earth. But Incnis Mrsi might miss some very advanced findings of astronomy…

Firstly, I do not “assume” and am interested in factual flux density, some upper estimate (at least, for land not very far from the equator and not very above the m.s.l.). An answer consisting of a link to measurement results (and possibly not a single formula) will qualify. Replies consisting...

I am interested in energy flux density from the Moon at Earth’s surface, specifically in infrared (albeit most of it comes in infrared anyway). Physics.SX (boyfarrell) gives an estimate 89 mW/m². I doubt it for several reasons. 400 K (as effective mean) on Moon seems to be unrealistically hot...

This looks exactly the thing I was interested in. The W boson governs interconversion between charged lepton and neutrino. Quantitatively, it defines an operator, but which namely are its eigenvalues and eigenvectors (in terms of e, μ, τ)? It seems to be related to so named ”Yukawa...

Ī̲’m no expert, but this may be related to decay of W and Z, for example.

Do three mass eigenstates of the charged lepton define the flavor eigenstates e−, μ−, τ− ? Ī̲ know that—for neutrinos—mass eigenstates do not correspond to νe, νμ, ντ . Can we define reasonable flavor states for leptons in any way other than the abovementioned two bases?

It’s commonly held that left and right photons interact with matter in exactly the same way, because electromagnetism “conserves parity”. But we know that P-symmetry, in our world, is generally broken. Even according to the Standard Model, when light propagates through some media, it interacts...

It was silly, about impossibility of any time-like curve. Even gravitational lensing provides a counterexample. But for a null geodesic in general position, can a curve arbitrarily close to the geodesic be timelike (everywhere)? This has nothing to do with global properties.

Sorry Ī know almost no English textbooks. If your linear algebra is strong enough to understand all https://en.wikipedia.org/wiki/Rotation_formalisms_in_three_dimensions and most of https://en.wikipedia.org/wiki/Versor , then you already have some notion of a Lie group and can try to learn...

So, Ī failed to compose initial question and the text at math.SE into one picture (in other words, read the question poorly). IMHO now there is no more miscommunication.

Incandescent bulb design You misunderstand why vacuum bulbs came out of fashion. You don’t need any non-radiative heat sink to maintain equilibrium; thermal radiation is sufficient for it. Vacuum has another disadvantage: it permits tungsten to evaporate too quickly.

First of all, the name of this particular singularity is “the cosmological singularity” (unfortunately popular resources such as Wikipedia do not emphasise distinction between “a singularity” as a common noun, and this concrete thing; not such great minds as R. Penrose write these). Also, the...

If two points of a globally hyberbolic pseudo-Riemannian manifold are connected by a null geodesic, then any curve connecting them is either null-everywhere, or must have a space-like piece. Purely space-like curves (in more than 1 spatial dimensions) are possible. Purely time-like curves are...

Yes, infinitary operations have their traps. That “sum–product” terminology tries to distinguish different types of generalization, but in the same time it becomes confusing (even for us).

The question is not mathematics, but a piece of poorly considered philosophy. There are many different geometries: Euclidean, affine, projective, pseudo-Euclidean, symplectic, metric, differential, Riemannian, pseudo-Riemannian, some others exist also (including such peculiar one as...