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

help-circle

  • This is not surprising at all. A well-matching referee is a scarce resource. Higher impact journals can typically find better-matching referees due to their perceived prestige, as well as the much lower number of manuscripts passing through editors and making to the referees (it is well known that high impact factor is a consequence of editorial selectivity). A better matching referee is more likely to comment on the more pertinent points on the actual research and will therefore not linger too much on superficial aspects such as grammar etc (which, once/if a manuscript is accepted, will be handled by copy editors). The same referee will likely also use different criteria for different journals regarding acceptance, where they usually focus more on high level stuff such as perceived innovation or impact to field etc for high profile journals, and more on technical details for more run-of-the-mill types.



  • 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.