Emergence and the stratification of physics into sub-fields

The concept of emergence is central to understanding sub-fields of physics and how they are related, and not related, to other sub-fields.

The table below shows a stratum of sub-disciplines of physics. For each strata there are a range of length, time, and energy scales that are relevant. There are distinct entities that are composed of the entities from lower strata. These composite entities interact with one another via effective interactions that arise due to the interactions present at lower strata and can be described by an effective theory. Each sub-discipline of physics is semi-autonomous. Collective phenomena associated with a single strata can be studied, described, and understood without reference to lower strata.

Table entries are not meant to be exhaustive but to illustrate how emergence is central to understanding sub-fields of physics and how they are related to one another.

What do you think of the table? Is it helpful? Have you seen something like this before?

I welcome suggestions about entries that I could add.

Comments

  1. AnonymousMarch 8, 2024 at 12:51 PM

    The Condensed matter length scale should go to 0.1 m. Materials science belongs there.

    ReplyDelete
  2. AdamMarch 8, 2024 at 5:37 PM

    It is a nice table.
    I would put vector bosons exchange (W and photon) with the gluon exchange. Shouldn't it be "alpha decay" instead of "beta decay" (or at least both).
    Also, I would put "periodic table" right in the middle between atoms and nuclear, and add "atomic spectra" to atoms.

    ReplyDelete
  3. AnonymousMarch 10, 2024 at 10:22 AM

    Hey Ross nice table I just wanted to add that I feel the interactions at the condensed matter level can be terribly important for Earth Sciences including the stuff in between. For instance the viscosity of the magma and the would be lava tends to give a reasonable expectation of the explosive power of the volcanic eruption if it occurs. And this viscosity is determined by the composition of the minerals in the material like check this link out https://upload.wikimedia.org/wikipedia/commons/thumb/f/f4/Mineralogy_igneous_rocks_EN.svg/300px-Mineralogy_igneous_rocks_EN.svg.png basically the rhyoliticic end is where you get the high viscous stuff. But in saying this you'd never be able to pin point where an eruption is going to occur just based on knowing information about minerals, as that tends to be caused by much larger scale interactions such as hot spots and lava plumes. As such I think the area of Geoscience is incredibly interesting when it comes to emergence with how you can see the impact of things at atomic scales (such as the fact an area of rock, would be more resistant to weathering if it is made up of harder minerals such as quartz which is also determined by atomistic interactions to form strong crystal structures), but have incredibly emergent phenomena throughout.

    ReplyDelete

Post a Comment

Popular posts from this blog

What is Herzberg-Teller coupling?

Image
Is it something to do with breakdown of the Born-Oppenheimer approximation? In molecular spectroscopy you occasionally hear this term thrown around. Google scholar yields more than 3000 hits. But I have found its precise meaning and the relevant physics hard to pin down. Quantum mechanics in chemistry by Schatz and Ratner is an excellent book , but the discussion on page 204 did not help me. "Herzberg-Teller" never appears in Atkins' Molecular quantum mechanics. So here is my limited understanding. Herzberg and Teller wanted to understand why one observed certain vibronic (combined electronic and vibrational) transitions that were not expected, particularly some that were expected to be forbidden on symmetry grounds. " Intensity borrowing " occurred. Herzberg and Teller pointed out that his could be understood if the dipole transition moment for the electronic transition depended on the nuclear co-ordinate associated with the vibration. In the Franck-Condo
Read more

Is it an Unidentified Superconducting Object (USO)?

If you look on the arXiv and in Nature journals there is a continuing stream of people claiming to observe superconductivity in some new material. There is a long history of this and it is worth considering the wise observations of Robert Cava , back in 1997, contained in a tutorial lecture. It would have been useful indeed in the early days of the field [cuprate superconductors] to have set up a "commission" to set some minimum standard of data quality and reproducibility for reporting new superconductors. An almost countless number of "false alarms" have been reported in the past decade, some truly spectacular. Koichi Kitazawa from the University of Tokyo coined these reports "USOs", for Unidentified Superconducting Objects , in a clever cross-cultural double entendre likening them to UFOs (Unidentified Flying Objects, which certainly are their equivalent in many ways) and to "lies" in the Japanese translation of USO.   These have caused g
Read more

What should be the order of authors on a conference poster or talk?

I welcome discussion on this point. I don't think it is as sensitive or as important a topic as the author order on papers. With regard to paper authorship my general rule is that the person who does the bulk of the work, including actually writing the paper should be the first author. Doug Natelson has a good post on co-authorship , that I largely agree with. My only difference is that I am not really convinced that good practice prevails in the majority of circumstances. I fear there are increasing numbers of co-authors, particularly senior ones, with marginal contributions. But, what about conference talks and posters? Many of these are based on work that is already or about to be published. Should the author order be identical as the associated papers? I am not sure it should necessarily be. My tentative view is that the person who writes and submits the abstract and actually prepares and presents the post/talk should be the first author. Perhaps they should also highlig
Read more