Quantum field without a particle is the same as vacuum?

Question

@ArnoldNeumaier @ArnoldNeumaier @ArnoldNeumaier A question to Arnold Neumaier, here https://arnold-neumaier.at/physfaq/topics/nothing you said 

''Nothing'' is modeled in quantum physics by the vacuum state - 
whether it is an empty input mode in a beam splitter or a quantum 
field without particles. So the question is whether a primordial 
vacuum could have dynamically changed into our universe.
 
Because of the conservation laws for momentum and energy valid in the 
standard model, it is impossible (under the currently accepted modeling 
assumptions in quantum physics) that a vacuum can turn into something 
nonvacuous in a region of space small enough such that gravitation is 
negligible. And indeed, such a thing has never been observed."

Vacuum means the quantum field without a particle. Are you saying this 
quantum field without a particle cannot become something unvacuous 
without the aid of gravity? If that so, so quantum fields without 
a single particle at all is the same as absolute nothing. 
Thank you.@ArnoldNeumaier  

Comments

It cannot become something unvacuious within the framework of quantum field theory. If gravity is modeled as a quantum field, the particle picture becomes observer dependent - what is a vacuum for one observer is a thermal field for accelerated observers. This is the Unruh effect. 

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Thank you for your response, sir. Unruh effect? That's interesting. In QFT, we can treat almost everything (i.e a part of an ocean or even a particular position in the universe) as a field @ArnoldNeumaier? 

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@Abdullah: A field is like a container of propertiesto be  found at certain pots in spacetime, one field for each property.