3,602 research outputs found
Credible, Truthful, and Two-Round (Optimal) Auctions via Cryptographic Commitments
We consider the sale of a single item to multiple buyers by a
revenue-maximizing seller. Recent work of Akbarpour and Li formalizes
\emph{credibility} as an auction desideratum, and prove that the only optimal,
credible, strategyproof auction is the ascending price auction with reserves
(Akbarpour and Li, 2019).
In contrast, when buyers' valuations are MHR, we show that the mild
additional assumption of a cryptographically secure commitment scheme suffices
for a simple \emph{two-round} auction which is optimal, strategyproof, and
credible (even when the number of bidders is only known by the auctioneer).
We extend our analysis to the case when buyer valuations are
-strongly regular for any , up to arbitrary
in credibility. Interestingly, we also prove that this construction cannot be
extended to regular distributions, nor can the be removed with
multiple bidders
Comment on "Density and Spin response of a strongly-interacting Fermi gas in the attractive and quasi-repulsive regime"
This is a comment on Phys. Rev. Lett. 108, 080401 (2012) by Palestini et al.
We pointed out that the diagrammatic method in that article violates gauge
invariance. As a consequence, there will a Meissner effect in the normal phase
and the contribution from collective modes are not mentioned in the
symmetry-broken phase.Comment: 1 page, no figur
Resonant Auger decay of the core-excited CO molecule in intense X-ray laser fields
The dynamics of the resonant Auger (RA) process of the core-excited
CO(1s) molecule in an intense X-ray laser field is
studied theoretically. The theoretical approach includes the analogue of the
conical intersections of the complex potential energy surfaces of the ground
and `dressed' resonant states due to intense X-ray pulses, taking into account
the decay of the resonance and the direct photoionization of the ground state,
both populating the same final ionic states coherently, as well as the direct
photoionization of the resonance state itself. The light-induced non-adiabatic
effect of the analogue of the conical intersections of the resulting complex
potential energy surfaces gives rise to strong coupling between the electronic,
vibrational and rotational degrees of freedom of the diatomic CO molecule. The
interplay of the direct photoionization of the ground state and of the decay of
the resonance increases dramatically with the field intensity. The coherent
population of a final ionic state via both the direct photoionization and the
resonant Auger decay channels induces strong interference effects with distinct
patterns in the RA electron spectra. The individual impact of these physical
processes on the total electron yield and on the CO electron
spectrum are demonstrated.Comment: 13 figs, 1 tabe
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