In summary: The assumption is that the probes (anti-D3-branes) will stay stable and consistent. That has not been the case so far, and it seems very likely that it will not be the case in the future.
Thanks for monitoring this frontier and highlighting it here! It is fascinating to see this happening. I can't wait to see what the dual to this twist will be.
Today the reply from Kallosh and Linde: http://arxiv.org/abs/1809.09018 Am unsure about their logic. It sounds like saying it's not their problem if the embeddings into 10d of their model doesn't work. Instead they feel free to further modify the 4d model.
Thomas von Riet comments (here): "it is distraction from the essence. Their original paper needs to be addressed and not some detail about a 4d SUGRA description failing at some far point in moduli space"
#74
mitchell porter
Gold Member
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I have avoided this topic since it is a little distant from my interests, but some string doubters excited that "Vafa's conjecture" might falsify string theory, provoked me to look at it again. The reason for the excitement is that the conjecture creates new constraints regarding dark energy, inflation, and so on. In particular, it is being reported that "the Higgs field also has properties that should actually be forbidden by Vafa's conjecture". The people who did the research surely consider this a reason to amend the conjecture, but for the string skeptics, the excitement is that maybe the Higgs boson already falsifies string theory.
What does the paper say is actually inconsistent with the "dS swampland conjecture" as currently formulated? The standard model Higgs... plus quintessence, and with only a minimal coupling between them. In the discussion, they link to some papers which already propose milder versions of the conjecture... But what interests me more is a related paper from Korea, which points out that a similar dS extremum exists for the pion scalar potential too.
To me this seems ripe for producing an outright counterexample to the conjecture as it stands. The Koreans consider (their eqn 26) a scalar potential involving the pion field and the quintessence field. Well, you should be able to get pions from a brane stack, and Vafa proposed that quintessence could just be a modulus associated with a Calabi-Yau handle. It doesn't sound that complicated (for a string theory vacuum): maybe strings compactified on a torus with one or two holes, with a brane or two wrapped around one of the them. So one hole has the pion branes wrapped around it, and the other hole provides the quintessence modulus...
