haruspex's latest activity

Whether Earth is moving toward or away from Jupiter is almost immaterial in itself. The orbital period of Io is about 42.5 hours. In...

Bingo. As should have been obvious, it would not have been possible to time an individual transit since that is defined as the period Io...

You're right - I was looking at the first line of the body of the post, the bit to the right of the"TL;DR". I just assumed the title...

I have a suspicion that some respondents are reading the thread title as "How can light be a wave and particle at the same time" instead...

That’s reading too much into the way the diagram is drawn. The distances 1-2 and 3-4 will be about the same, but not exactly. Suppose...

The text is clarified somewhat by the caption on the figure: "When the Earth moves away from Jupiter during a transit." I.e. it’s not...

Infinity is to do with things. How you can discuss things rigorously without developing a theory of sets eludes me.

We are: The normal force between two bodies is, by definition, normal to the plane of contact of the bodies (if that is well defined)...

"not moving at all" may be misleading. Its instantaneous velocity is zero, but it is accelerating upwards.

What if we define ##f(x)=1+\ln(x)##, ##g_{n+1}(x)=f(g_n(x))##, ##h_{n+1}(x)=h_n(x)g_n(x)##, with suitable settings for ##g_0, h_0##, for...

I agree.

What do you know about linear transformations and collapse of dimensions?

I think you mean it is not surjective. Or to put it another way, that transformation collapses the plane (x, y) into the line (0, y)...

Why exclude 0? Edit: And what about ##a+b\sqrt5 \to qb+ra\sqrt5##?

I think it is a matter of spotting that G+ is isomorphic to a much more familiar object and applying a standard result. The word...