@PeterDonis from what you have said would it be correct to say that the different cosmology models have to take into account predictions made by QFT but they dont modify it
yes but here you are talking about different QFTs and how they don’t modify the basic properties of QFT but my questions was about cosmology models.
by this you do mean cosmology models don’t in fact modify QFT right?
@PeterDonis
yes I understand QFT is a framework and not an individual theory, what i meant is if the basic properties/rules of QFT are modified in models that are different from the ##\Lambda C D M## model
I know that cosmology usually deals with general relativity but what about QFT, is it modified depending on the cosmological model? Or is it not something that change with the model used.
another confusing thing is the supposed reason why their model is better, "Note that the Hamiltonian is constraint and must be zero — a fact that follows from the time reparametrization invariance of
general relativity. From the existence of these structures it is easy to verify that the...
yes I saw the their damping oscillator example and that I can understand, what im confused about is how they use that same logic in cosmology, in the oscillator example like you said there is a dissipation of energy due to damping interactions, but when talking about the universe where there is...
the reason I said that is because they say that non conservation of energy is a feature of their model as oppose to a regular closed system where energy is conserved. "Throughout this work, we have investigated different inequivalent ways in which dynamical systems can be considered closed...
In the paper, the authors argue that a closed system can exhibit features of an open system one of the being the non-conservation of energy, my questions how can a closed system have non-conservation of energy. (I know in GR, conservation of energy is subtle issue but it doest seem like the...
from the little i understand there are certain symmetries that are broken in quantum field theory, i also know that gauge symmetries must cancel in order to avoid inconsistencies in the theory.
if gauge anomalies need to be cancelled does that mean they dont correspond to a physical...
another reason I was curious is because whenever I look through discussions or questions regarding QM (for example my question about conservation of energy in QM in that previous thread) most answers are with respect to quantum mechanics in general without mention of a formulation/picture which...
The reason I asked is because I came across a thread in physics stack that mentions that there are ways to make the Heisenberg and Schrödinger formulations non-equivalent and then I remember your comment from that previous thread here and got me wondering if the formulation one uses changes...
so just for further clarification when someone says something is true or holds in standard or basic qm, the formulation (e.g Heisenberg, Schrödinger, interaction, etc) is not relevant?
so what you said in that thread I mentioned,
"However, it should be noted that, in basic QM (i.e., without adopting any particular interpretation--discussion of how particular QM interpretations deal with collapse belongs in the interpretations subforum), "collapse" is not claimed to be an...