2,645 reputation
1420
bio website
location Belgium
age 23
visits member for 1 year, 8 months
seen 45 mins ago

Aug
24
comment About solitons, what is the difference between kinks and vortices?
I want to add another outstanding book with introduction to solitons, instantons and the like: "Gauge field theories: an introduction with applications" by M. Guidry (1991). This is a personal favourite of mine because Guidry's style of rhetoric clicks well with my internal thought process. Another good reference I know is "Solitons and instantons: An introduction to solitons and instantons in quantum field theory" by R. Rajaraman (1982).
Aug
19
comment How much energy would the Human Torch need?
You don't have to take the mass of the average person, Human Torch weighs 170 lbs. :P
Aug
16
comment Unknown letter ℑ used in an equation
This isn't really the kind of questions we answer here but Detexify can often help, since the LaTeX command to write a symbol usually has a somewhat telling name (in this case \Im, meaning "the imaginary part of"). You might have guessed that from the equation itself based on Euler's formula. Actually, I just read the last part of the accompanying text and it says so there as well, so now I'm confused as to why you asked...
Aug
15
awarded  Nice Answer
Aug
9
comment Finding the mass of pure matter
@celtschk and the people who voted earlier: I've edited my answer. I can't comment more on the implications of having a Planck density right now, but sufficit to say this is quantum gravity territory.
Aug
9
revised Finding the mass of pure matter
Replaced apparently popular hogwash with some Planck-stuff
Aug
9
answered Finding the mass of pure matter
Aug
9
comment Finding the mass of pure matter
What do you mean "not made up of particles"? Let's start here: what is matter to you?
Aug
9
comment Finding the mass of pure matter
I'm sorry but I have no idea what you mean. And I'm pretty sure 1 meter squared is a surface. ;-)
Aug
8
comment Why is electron presented in books, pictures as a sphere?
@albedo Concerning your other question: note that we talk about the electric field of the electron when discussing its shape. Like Colin McFaul mentions in his answer, as far as we can experimentally tell the electron is a mathematical point. However, you can define a boundary for the electron if you want to, based on the value of its electric field. Strictly speaking this is an arbitrary choice but sometimes it may be helpful to associate a natural size with an electron and treat it as a little sphere.
Aug
8
comment Why is electron presented in books, pictures as a sphere?
@albedo This webpage and the answers to this PSE question might be interesting reading material for you.
Aug
8
comment Why is electron presented in books, pictures as a sphere?
@albedo The electron (like all elementary particles) is not both a particle and a wave, that's a common misconception. It is in fact not a particle, nor a wave. In the most accurate theories we currently have about the universe elementary particles are in fact excitations of quantum fields. These excitations, also called 'quanta' (from the singular 'quantum'), exhibit both particle-like and wave-like features but the truth is that both waves and particles are classical and macroscopic concepts. There's no reason for the smallest building blocks at the micro-level to be either one.
Aug
5
comment Is it true that the Schrödinger equation only applies to spin-1/2 particles?
I don't know if I should post a link to the paraphrased answer on Quora now. Perhaps not if OP prefers it that way, I'm sure people can find it themselves by means of a simple websearch.
Aug
3
comment How to numerically solve a complex equation?
Would Mathematics be a better home for this question?
Jul
29
comment Why was theory of cosmic aether discarded?
Consider changing your question title to better match what you're asking in the main body.
Jul
28
awarded  Convention
Jul
27
comment How to derive this formula?
I know the question got answered and closed already, but I strongly suggest picking up a book on classical mechanics. I mean, don't let it discourage you (really!) but this is very basic stuff: you know the acceleration vector $\mathbf{a}$ (at all times), the initial velocity vector $\mathbf{V}$, and the initial position doesn't really matter (but the origin is often chosen). From this information you can write down $a_x(t)$, $a_y(t)$, $v_x(t)$, $v_y(t)$, $x(t)$ and $y(t)$. Using the notation of your picture, your question just boils down to: what is $x(t_1)$, if $y(t_1)=-Yi$?
Jul
22
comment why are the anthropometric units (which are about as big as we are) as large as they are relative to their corresponding Planck units?
Thank you for clarifying OP's question for me. Asked in that way, it is indeed nontrivial. Very nontrivial even, especially since - like you say - we can only comment on the way things currently are on our planet.
Jul
22
comment why are the anthropometric units (which are about as big as we are) as large as they are relative to their corresponding Planck units?
@robertbristow-johnson What we prefer depends on context and in any case human preference does not imply validity. So the value of $c$ in metres is no more 'correct' than its value in e.g. beardseconds or Astronomical Units.
Jul
21
comment Symmetries of the Standard Model: exact, anomalous, spontaneously broken
@Gro-Tsen I'm still not entirely convinced but I do think the community wiki idea is a good one. I'm not sure how quickly the table would get completely filled though. Like you I don't have the time or resources to start an independent project (mostly time is a problem as I don't think too many resources would be needed), otherwise I'd love to get myself into it. Lots of interesting stuff to learn while constructing such an overview, I'm sure.