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Explaining metastability


When I have to explain metastability, I always use the example of atomic nuclei. Iron is the only stable atomic nucleus. The rest of the atomic nuclei are only metastable. Nevertheless we can use statistical mechanics to describe chemical systems. The key feature here is separation of time scales. The timescale for atomic processes is much longer than the time scale of chemical reactions.

Actually chemical substances are another example of metastability. In quantum chemistry they have several methods for calculating the speed of a chemical reaction. All these methods rely on a crucial assumption that the vibration of the molecule is well described by a thermal equilibrium distribution. In other words they rely on an assumption of metastability. Once again the key assumption is separating time scales. The time needed to attain vibrational equilibrium is shorter than the inverse reaction rate.

The explanation of metastability does not relate well to macroscopic systems and electronic systems, particularly the figure, point 1 is a h1gh energy stable point , point 2 is a metastable point , point 3 is the lowest energy stable point. At a metastable point, the system can go either way, and hesitstes for a long time until "noise" nudges it one way or the other. It's like a spinning coin it eventually has to end in heads or tails [two possible ground states] (or balanced on the flat edge [one high energy semi-stable point]), or it could briefly teeter on a corner (metastable point, [two of those])
The distinction between stable and metastable should be based on the derivative of the curve, if it is upward sloping at the zero crossing , then it is stable , if the zero crossing is negative sloping then the point is metastable. Salbayeng (talk) 23:28, 7 March 2020 (UTC)[reply]

Basic attention needed


You better believe this article is "start class". It is a simple concept at its heart that is impossible to understand based on this article unless, perhaps, you already know what it is. When dictionary.com is more informative, one has to wonder what planet you guys are on. I have entered a new article on metastability on simple.wikipedia.org which actually says what metastability is, a goal that apparently is out of reach on en.wikipedia.org. —Preceding unsigned comment added by (talk), 24 May 2010 (UTC)

Lead section inadequate


I find that the lead section is absolutely unintelligible, with too many lucubrations and too few sound concepts. By reading it, I can understand metastability only because I already know what is metastability. So, I think it is to be completely rewritten. --GianniG46 (talk) 19:11, 17 October 2010 (UTC)[reply]



perhaps can add a reference to the mechanical "over center" lock or latch. — Preceding unsigned comment added by Charlieb000 (talkcontribs) 00:45, 10 January 2014 (UTC)[reply]

Electron systems in biochemistry


Section as it stands as of 14 February 2017: The evolution of a many-body quantum system between its characteristic set of states may be influenced by the following external actions:

  • The environment may act chaotically on the system, adding uncertainty to all state energies (while decreasing their lifespans) – as in spectral line broadening.
  • Resonant exterior actions may nudge the system into a lower cohesive energy state while making it release an intrinsic amount or quanta of its energy – as in stimulated emissions.
  • Alternatively, external catalytic fields of forces may briefly flatten some of the barriers (ridges separating adjacent valleys) in the potential landscape of the system and help it tunnel through to lower energy states.
  • Under the impact of thermal or directional external actions, some systems (see macromolecule complexes involving enzyme-cofactor association) may wander for extremely long periods of time among a certain sub-group of their states (all having distinct configurations but energy differences within the thermal fluctuation range). As such the enzymes will enter a biochemical reaction sequence with an initial configuration, perform the many steps of the sequence as catalysts while continuously contorting, and eventually leave that reaction sequence in the same configuration as they entered it, ready to perform again.

This section seems to be roughly on topic, but the concepts are not well-connected. The first three points do not seem to apply to biochemistry any more than they apply to many other fields of chemistry. If these points are of particular interest in biochemistry, more explanation is needed. The last bullet point is an example of why metastability is important to complex biological systems, but does not make the connection clear enough for those who are not already familiar with the concept(s).Elriana (talk) 02:01, 15 February 2017 (UTC)[reply]

Removed the section for now. Marginally on topic but the connection is not explained. Without a source, it would be hard for anyone to reconstruct where the particular set of ideas came from and improve it in the future. The section goes into too much detail and confuses people in an article that's already full of examples and low on basic concepts. CyreJ (talk) 16:44, 11 April 2020 (UTC)[reply]