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Today I learned that skills improved by participating here on scienceforums can, at least in some minor way, be helpful in the current virus situation. I joined a local initiative where students studying from home can ask about math and physics. Debating science here has made me more confident regarding mainstream science and how to respond with useful hints (instead of solutions) to homework questions.

I know I am not supposed to get involved as I have already acted as a moderator (but hopefully in a fairly non-contentious way), but I can't resist the need to point out that there are two ways of defining something: 1. In terms of something else (which is, hopefully, simpler) 2. As an axiom (or postulate or "self evident truth" or whatever) in which case the thing is defined as simply being itself. (I believe this is what "Lawbringer" is referring to as a "circular definition".) All definitions must eventually bottom out to (2). I would not call that a circular definition as I think it is useful to distinguish fundamental concepts that cannot be defined in terms of anything else, from the circular definitions which are often the basis of a fallacy (similar to begging the question).

Well there are good reasons to call the virus and disease the way it is called. First the virus name is not provided by the WHO but by the International Committee on Taxonomy of Viruses (ICTV). SARS-CoV-2 is short for "Severe Acute Respiratory Syndrome Coranavirus 2". Based on their approach the ICTV found that the the new virus is not sufficiently (genetically) different from the previously identified virus named SARS-CoV, the causative agent for the SARS disease. Naming it Wuhan Virus or something like that would essentially go against all naming conventions. The disease itself is named simple Coronavirus Disease 2019 (COVID-19).

Of course it helps! Does it help you to understand what words mean when you read something?!?! Geez. Give me a fucking break.

Actually, one story I always enjoyed is the story about how ancient sheep herders used to know when they didn't have all the sheep at the end of the day, even though their mathematical abilities were similarly basic. They just used rocks. One rock for each sheep. And if there were rocks left at the end of the day they knew, even though they couldn't count that far, that they had missing sheep. The rocks were called calculi and that's where the word calculus comes from. I guess humankind was more pragmatic in those times. Similarly Cantor used this one to one correspondance idea for his proofs on infinities. You can't actually count to infinity, now, can you? But if you know that there's a one to one correspondance ...

This is a discussion forum.

Covid-19 is the disease and sars-cov-2 is the virus.

Hmm... Wikipedia says: "Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)" https://en.wikipedia.org/wiki/Coronavirus_disease_2019 That would mean that COVID-19 is the name of the illness (or disease, is this the same?), while SARS-CoV-2 is the name of the virus. (bad names, if you ask me - I guess, intentionally bad names)

! Moderator Note Come back when you can stay to actually discuss a subject and support your arguments regarding it. This is a science discussion forum. Thread closed.

I'm not sure you understand the point of mathematics. A square is axiomatic, how is that circular???

http://geocalc.clas.asu.edu/GA_Primer/GA_Primer/introduction-to-geometric/defining-and-interpreting.html The first thing that came to my mind is how the geometric product is defined in geometric algebra. The inner and outer product are defined using the geometric product, and the geometric product is defined using the inner and outer product. Just look closely.

What is wrong with solving problems by computation? After all it is what people tend to do these days. Maybe it also helps to know if and where you have possibly seen an actual mathematical definition that is circular?

! Moderator Note You had your chance to bring some rigour and science to this discussion. Instead all you have is baseless assertions. Clearly this "theory" is not ready for serious discussion. The thread is closed. Do not bring this subject up again.

! Moderator Note I am happy with it so far. It introduces, reasonably clearly, an important fact about definitions which could lead to an interesting discussion. I will move it to Philosophy though, as the issue is wider than mathematics. (I will also be keeping a close eye on it.)

Why does it matter? We get sick and, hopefully, we learn to deal with it...

Indeed, so why does it matter?

I'm guessing you've missed my point, given the negs... My dog barks at a cat, even if the cat turns out to be another dog?

I don't need to derive geodesic equations: I can simply state that the anti-photon engages the next two negative spacetime events thereby possibly changing its direction of motion. We associate numbers to negative events simply by stating: CB("Name of Coordinate System", -ngx_1 - mgx_2 - lgx_3 - kgx_4), where x_i element of unit vectors on R^4, n, m, l, k element of N, g element of R. From Figure 1.5 we see that an electron may emit a photon or an anti-photon (the two electric charge circles). To create a photon from an electron we need: an operator called a copier, a charge copier and a charge transport operator. We work in the reference frame of the Centre of Mass of the electron. The copier must copy the circle of S_2 and the Riemann Sphere of S_2 itself. Then the carge copier must make 2 copies of the charges on S_2, then the charge transporter must move two of the copies as follows: move the copied charge from (1 - idelta) to (-delta - i) and the one from (-1 - idelta) to (delta -i). Then the other copy of the right sided charge must move to (1 - i(delta + lambda)) and on the left to (- 1 - i(delta - lambda), with lambda chosen by the observer so that the line between the left and right charges is prependicular to the momentum direction. Since lambda > 0 we have the momentum not precisely in the "up" direction. The same orientation as a reference photon. They are seen as phase shifted photons. Space is made of numbers. I reject the strong force, I think we can do without it. See anti-photons as phase shifted photons going back in time. What is not compatible with the standard model?