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Hasn't the Casimir effect given possible real life negative energy densities?

by xupybd 5y ago

pdonis 5y ago
No. All that happens in the Casimir effect is that the vacuum state between a pair of uncharged plates is slightly different from the vacuum state in the absence of all matter whatsoever. There is no "negative energy" anywhere in the Casimir effect, despite pop science articles that appear to claim the contrary.
- xupybd 5y ago
  I'm probably wrong but I thought the argument was being made that you could generate the same effect? https://hal.archives-ouvertes.fr/hal-00981257/document#:~:text=Alcubierre%20was%20the%20first%20to,warp%20drives%20needs%20astronomical%20quantities https://hal.archives-ouvertes.fr/hal-00981257/document#:~:te....
  - pdonis 5y ago
    This paper is claiming that the Casimir Effect could be used to generate a "Natario warp drive spacetime", but the validity of that claim is questionable. (As far as I can tell, this paper has not been peer-reviewed so its claims have not been checked by other experts in the field.) Also, even if the claim about the Casimir Effect is correct, since the Casimir Effect occurs between a pair of uncharged plates, the "warp bubble" would have to be between the plates--but that means the warp bubble can't move the plates, so using it as a "warp drive" would not be possible.
    - xupybd 5y ago
      Again I suspect there is more that I don't understand but this paper goes into geometries that could possibly lead to being able to generate the required negative energy.https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-021-09484-z https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-02... That said I think you still need such huge energies that it's impractical.
      - pdonis 5y ago
        > this paper goes into geometries that could possibly lead to being able to generate the required negative energy The geometries in question don't generate negative energy, they are generated by negative energy (which actually isn't a very good term for the kind of stress-energy that is involved). This paper is just talking about different possible geometries that could exist between Casimir plates, based on different possible configurations of "vacuum energy" that could exist between the plates. Even if one of these geometries turned out to be a "warp bubble", it still wouldn't change the issue that I described before, that all of this is taking place between uncharged plates, and the plates are outside the "warp bubble" so the bubble can't move them, so this is not a viable option for an actual "warp drive".
        xupybd 5y ago
        Good to know thanks for the explanation.

Hasn't the Casimir effect given possible real life negative energy densities?

by xupybd 5y ago

Hasn't the Casimir effect given possible real life negative energy densities?

No. All that happens in the Casimir effect is that the vacuum state between a pair of uncharged plates is slightly different from the vacuum state in the absence of all matter whatsoever. There is no "negative energy" anywhere in the Casimir effect, despite pop science articles that appear to claim the contrary.

xupybd 5y ago
I'm probably wrong but I thought the argument was being made that you could generate the same effect? https://hal.archives-ouvertes.fr/hal-00981257/document#:~:text=Alcubierre%20was%20the%20first%20to,warp%20drives%20needs%20astronomical%20quantities https://hal.archives-ouvertes.fr/hal-00981257/document#:~:te....
- pdonis 5y ago
  This paper is claiming that the Casimir Effect could be used to generate a "Natario warp drive spacetime", but the validity of that claim is questionable. (As far as I can tell, this paper has not been peer-reviewed so its claims have not been checked by other experts in the field.) Also, even if the claim about the Casimir Effect is correct, since the Casimir Effect occurs between a pair of uncharged plates, the "warp bubble" would have to be between the plates--but that means the warp bubble can't move the plates, so using it as a "warp drive" would not be possible.
  - xupybd 5y ago
    Again I suspect there is more that I don't understand but this paper goes into geometries that could possibly lead to being able to generate the required negative energy.https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-021-09484-z https://link.springer.com/article/10.1140%2Fepjc%2Fs10052-02... That said I think you still need such huge energies that it's impractical.
    - pdonis 5y ago
      > this paper goes into geometries that could possibly lead to being able to generate the required negative energy The geometries in question don't generate negative energy, they are generated by negative energy (which actually isn't a very good term for the kind of stress-energy that is involved). This paper is just talking about different possible geometries that could exist between Casimir plates, based on different possible configurations of "vacuum energy" that could exist between the plates. Even if one of these geometries turned out to be a "warp bubble", it still wouldn't change the issue that I described before, that all of this is taking place between uncharged plates, and the plates are outside the "warp bubble" so the bubble can't move them, so this is not a viable option for an actual "warp drive".
      - xupybd 5y ago
        Good to know thanks for the explanation.