• 1 Post
  • 32 Comments
Joined 1 year ago
cake
Cake day: July 3rd, 2023

help-circle


  • I’ve seen similar things with a physical keyboard connected. There are plenty other Android apps that can handle connected keyboards corrected by not showing the on screen keyboard(OSK) (the now defunct RIF being one). Right now the only way to not have flashing OSK is to turn it off system wide under android settings, which is not ideal (because it won’t turn itself on automatically when the physical keyboard disconnects)


  • current carrying wire of finite length

    Well I suppose a cheesy way of putting this is that there is no such thing as a “current carrying wire of finite length”, by itself.

    To expand, just because one can calculate the contribution to the magnetic field at some spatial point from such an object, doesn’t mean it is the sole source of the field in a theoretically consistent manner. If you complete the “loop” with two semi-infinite horizontal wires, and another vertical wire at infinity (assuming it has an emf there to power the circuit), then the field will change due to the two horizontal wires. This construction however breaks rotational symmetry around the original wire (so you’ll not be able to compute the loop integral simply as B times circumference), and in order to restore that, instead of just two horizontal wires, you’ll have to have infinite such pairs in all radial directions (like a squeezed coaxial cable). Anyway, I guess the point is after “completing the circuit”, the “paradox” will no longer be there.


  • The Ying Yang is the “shape” of the light source. The point is that their technique can be used to infer the shape of an unknown light source, among other things. In so far as the data being recorded in the experiment involves two photons (or really, many identically prepared copies of two photons over time) and therefore 4 spatial dimensions (x y for each), then yes the 2d image they show is necessarily “interpreted” from the 4d “raw image”. Exposure time is 1min according to the paper, so not quite “real time”, but the whole theory is time independent (no time in any equation), so I imagine it can be shortened with e.g. higher laser power.

    caveat: not an optics person so grain of salt…



  • Appreciate the uplifting spirit, but not sure who this list is for. Physics undergrad? Talk to a professor. In grad school? Probably already has some personal taste and knows how to pick books that best suit one’s own style and need (plus talk to your peer/professor). Budding enthusiast? Pick a topic of interest and go from there – life is short, no need to waste time on every standard text book.

    Also, quite a negligence not mentioning a single book from Landau & Lifshitz.



  • To be fair, time crystal is a real – albeit somewhat clickbaity – concept in physics, proposed by none other than the Nobel laureate Wilczek. In simple terms, a time crystal is something whose frequency is not a harmonic of what’s driving it (e.g., its periodicity could be double that of the drive). It’s a “crystal” because it’s breaking the (temporal) symmetry of the governing theory, just as a conventional crystal, by forming into a lattice of atoms, breaks spatial translation symmetry.










  • Mind you, the DFT calculation from the Griffin paper is not a proof of LK 99 being a superconductor in any way. What it showed is the (potential) formation of flat bands near the Fermi surface. Band dispersion is associated with the kinetic energy of the electrons, so materials with flat band (and therefore electrons with suppressed kinetic energy) at the Fermi surface are more susceptible to interaction effect (and strong interaction causes all sorts of nonintuitive quantum effects). I’m not a DFT expert in any sense, but from what I’ve heard, it is quite easy to “tune” your model to produce narrow (the limit of which being flat) bands from substitutions (e.g. the Cu substitution in this case) and such, which don’t necessarily lead to superconductivity.

    So I’ll take the DFT papers (there are quite a few now) as saying, “hey you want some flat band? Here’s some. We’ve done our part. Now some other theorist, do your magic and conjure up some superconductivity”. It’s a cog in the full picture, if there is a full picture



  • galilette@mander.xyztoScience Memes@mander.xyzpeer review
    link
    fedilink
    arrow-up
    11
    arrow-down
    1
    ·
    1 year ago

    Resubmitting to multiple journals is not a typical (nor the “right” one however it is interpreted) strategy though (at least not in physical sciences). You’ll usually ping the handling editor, who will then contact the referee on your behalf. The referee will then either “promise a report soon”, or, in the event they didn’t reply, the editor will find another referee. Nowadays with arxiv and such, there is usually no rush to actual publication as far as priority is concerned.

    I’d also say, don’t take the combative mindset as suggested in the comic. Think of it more as having some fresh pairs of eyes to check your work as well as communication (if a referee misunderstood something in your paper, chances are many readers will as well).