it's so hot with the indoor room temperature 33 degrees Celsius shortly after noon.

@bolbteppa I mean the book expanded by Jim Napolitano: amazon.com/Modern-Quantum-Mechanics-J-Sakurai/dp/1108422411/…

wait, never mind

a 3rd edition is coming :P

relativitycalculator.com/Newton_Universal_Gravity_Law.shtml

Why is $\frac{k}{4\pi r^2}=\frac{c}/M$

and $f=(kmM)/r^2$ not $(4\pi^2)/r^2\sqrt{MmcC}$?

in the link?

when u know the answer please tag me. Thank you!

helo everyone

You've made a typo in your first equation @Stupidquestioninc, there's a / in the denominator?

@Charlie sorry matjax is not working so lemme check once again

@Charlie apologies I mean this $\frac{k}{4\pi r^2}=\frac{c}{M}$

well it seems like I need to ask in another platform

You could try asking on the main site physics.stackexchange.com @Stupidquestioninc, questions do get answered in the chat but if you want a wider audience to see it you should ask on the main site

@Charlie hmm this question seems too basic to get answered. In other words embarassing : P

I've asked some trivial question on there in my time, don't worry :P

sure sir

The stuff near the end is interesting

I wonder what is the best balance of intuition and reasoning

Intuition can feel very deep, but without words to articulate it properly, it is not unsable

Meanwhile, systematic rigor can lead to things to be overlooked

does "systematic rigour" not by definition avoid overlooking things?

pbs spacetime video are always well made

no it can overlook certain insights

For example, some data can be noise like but it is actually resolved beautifully if given a certain abstraction supply by some model

That is common in particle physics

Also rigor based thinking can overlook things that sounds too out of this world because of a set way of thinking

Meanwhile, intuition is too imprecise to say much on its own, and there is no error checking

I guess we define intuition differently, I've never really thought that word had much meaning, to me rigour is just systematic intuition

But I think maybe a more common definition is "not getting bogged down in specifics" or "being able to solve a problem without deconstructing it"

The prescription for multi-particle quantum systems is the same as for systems with more degrees of freedom, right? ie. two non-interacting particles in the infinite square well live in $\mathcal H\otimes \mathcal H$, which is the same state space as a single particle in the 2-dimensional infinite square well.

There is an isomorphism between $L^2(\mathbb{R}^n) \otimes L^2(\mathbb{R}^n)$ and $L^2(\mathbb{R}^{2n})$, yes

oh interesting ok ty

How do I contact not-beginner programmers to chat with them? Cuz I figured most Discord groups have people that are there to actually learn programming :d

You could try the chat for the coding section of SE, if they have an active one idk

"the coding section of SE"...you mean SO? :P

ah yes the largest part of the entire website :P

I think the link derivation sucks.May be derivation by proportionality is better it makes much sense defining $k$ like that was to force both mass to exist in the formula. I think it is most likely be Newton observed multiplication of mass is proportional to force.

At school they blindly teach law of universal gravitational which of course isn't universal and in university they just ignore it or go with vauge derivation.

What makes you say it isn't universal?

doesn't apply on huge celestial mass

depends what you mean doesn't work :P

even gr "fails" at the "centre" of black holes

well it seems u r right :P everything depends

sounds like we r really ignorant in knowledge of gravity

please don't use textspeak ('u', 'r') excessively around here

@ACuriousMind why?

also, we understand plenty about gravity! Except for fringe cases where quantum gravity becomes relevant and which we haven't until now observed in practice, either Newtonian gravity or GR is perfectly sufficient

@Stupidquestioninc some people h8 it

@Stupidquestioninc From the chat guidelines linked in the room description:

> Use correct spelling, punctuation, and grammar to the best of your ability. Avoid rapid, short messages and txt spk/l33tspeak. These are often hard to read and take up valuable screen space. Txt spk may save you time typing, but it imposes a huge reading overhead on others - you're simply offloading your communications work onto everyone else.

@ACuriousMind ok I ndestand

well you did remove the u and r

i guess that counts

this place is informal, but it's still also meant for people who might not be familiar with it or find it off-putting