As Steven Weinberg put it, "the idea of quantum field theory is that quantum fields are the basic ingredients of the universe, and particles are just bundles of energy and momentum of the fields." At least, this is one way to look at QFT. The other approach is to imagine that these particles are really the fundamental indredients, and that quantum fields are just operators that emerge naturally from Hilbert spaces where particles can be created or destroyed. Personally I happen to like the first approach because IMO it makes spin and identical particle statistics easier to understand.(adsbygoogle = window.adsbygoogle || []).push({});

If String Theory is correct, is there any way of preserving -- with modification -- the "field first" approach to QFT? It seems that String Theory says that the "particle first" approach to QFT is better because it is closer to the actual truth: particles *are* fundamental, they're just not point-like.

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# QFT and String Theory

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