Born oppenheimer approximation vs adiabatic approximation

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The discussion centers on the Born-Oppenheimer approximation and its relationship with the adiabatic approximation in quantum mechanics. The term "adiabatic" is clarified to mean "no passage" between potential energy surfaces in this context, differing from its thermodynamic definition. Participants express a desire for further understanding of how adiabatic processes apply across various branches of physics. The usefulness of Wikipedia as a resource for scientific explanations is acknowledged, particularly regarding the adiabatic theorem. The conversation concludes with a focus on the need to understand why the Born-Oppenheimer approximation is synonymous with the adiabatic approximation in quantum mechanics.
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I'm learning to deal with h2+ (hydrogen ion) problems and the like, which sure entails the infamous born oppenheimer approximation .
i know the word "adiabatic" in a thermal sense, that is , an adiabatic process is the one in which no heat transfer occurs between the things of question and surroundings.
but , I don't quite understand that in quantum mechanics ,how the notion of "adiabatic" enters the story, say, in particular born oppenheimer approximation and adiabatic approximation is synonym .
it's said that the notion of adiabatic has a lots of applications in many branches of physics, would anyone please but tell me some of them?

many thanks in advance :D
 
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Adiabatic in thermodynamics has a different meaning than in molecular quantum mechanics.
In greek it signifies "no passage" or "no trespassing", however who or what is not passing is different in different contexts:
On a greek airport, it is persons, in thermodynamic it is heat and in molecular physics it is no passing from one potential energy surface (electronic state) to the other.
 
many thanks first! I got to apologize for delayed reply .
Actually I'd took a glance at the wiki's explanation contained in the first link before I put up
this question here. I usually distrust wiki. However, The second link is quite helpful. I'm reading it now while typing message to you . Seems like even serious science stuffs in wiki can be trusted sometimes.
regards :D
 
THanks very much for your reply. I think your interpretation of adiabatic hit the spot. I guess adiabatic ,roughly speaking , pretty much has to do with an isolation from the environment in a certain form. but it still remains to us the question why in particular born oppenheimer approximation is another name for adiabatic approximation in quantum mechanical sense .
cheers,
 
Time reversal invariant Hamiltonians must satisfy ##[H,\Theta]=0## where ##\Theta## is time reversal operator. However, in some texts (for example see Many-body Quantum Theory in Condensed Matter Physics an introduction, HENRIK BRUUS and KARSTEN FLENSBERG, Corrected version: 14 January 2016, section 7.1.4) the time reversal invariant condition is introduced as ##H=H^*##. How these two conditions are identical?

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