4 research outputs found
Strong unitary and overlap uncertainty relations: theory and experiment
We derive and experimentally investigate a strong uncertainty relation valid
for any unitary operators, which implies the standard uncertainty relation
as a special case, and which can be written in terms of geometric phases. It is
saturated by every pure state of any -dimensional quantum system, generates
a tight overlap uncertainty relation for the transition probabilities of any
pure states, and gives an upper bound for the out-of-time-order
correlation function. We test these uncertainty relations experimentally for
photonic polarisation qubits, including the minimum uncertainty states of the
overlap uncertainty relation, via interferometric measurements of generalised
geometric phases.Comment: 5 pages of main text, 5 pages of Supplemental Material.
Clarifications added in this updated versio
Testing the reality of Wigner's friend's observations
Does quantum theory apply at all scales, including that of observers? A
resurgence of interest in the long-standing Wigner's friend paradox has shed
new light on this fundamental question. Here---building on a scenario with two
separated but entangled "friends" introduced by Brukner---we rigorously prove
that if quantum evolution is controllable on the scale of an observer, then one
of the following three assumptions must be false: "No-Superdeterminism",
"Locality", or "Absoluteness of Observed Events" (i.e. that every observed
event exists absolutely, not relatively). We show that although the violation
of Bell-type inequalities in such scenarios is not in general sufficient to
demonstrate the contradiction between those assumptions, new inequalities can
be derived, in a theory-independent manner, which are violated by quantum
correlations. We demonstrate this in a proof-of-principle experiment where a
photon's path is deemed an observer. We discuss how this new theorem places
strictly stronger constraints on quantum reality than Bell's theorem.Comment: In v1, v2 we claimed to give the first rigorous proof of Brukner's
theorem, interpreting his "Observer Independent Facts" assumption to be
weaker than what he formalized. This was inaccurate (Brukner's theorem
follows from his assumptions) and obscured the significantly stronger
implications of our theorem. In v3 we name the weaker assumption in our
theorem "Absoluteness of Observed Events
Effects of piperonyl butoxide synergism and cuticular thickening on the contact irritancy response of field Aedes aegypti (Diptera: Culicidae) to deltamethrin
Background: Exploiting indoor-resting mosquitoes' innate behavioral responses to commonly used insecticide is crucial in vector control programs. Indoor residual spraying (IRS) and long-lasting insecticidal nets (LLINs) treated with pyrethroids have become widely used for controlling dengue fever vectors. The present study tested the effects of piperonyl butoxide (PBO) synergism and cuticular thickening on the contact irritancy response of field A. aegypti (Diptera: Culicidae) to deltamethrin in Taiwan and Thailand.
Results: The escape response of field mosquitoes treated with PBO was significantly elicited, with an escape percentage increase between 2- and 10-fold. In addition, the escape time was significantly lower in PBO-pretreated mosquitoes compared with field mosquitoes treated with deltamethrin alone. PBO-pretreated mosquitoes from seven out of 11 field strains exhibited a knockdown percentage of 11.23-54.91%, significantly higher than that of mosquitoes in corresponding strains treated with deltamethrin only. The Annan, Zhongxi, Sanmin, and North strains exhibited weak knockdown responses (≤3.75%). The mortality of PBO-pretreated field mosquitoes increased 2- to 75-fold compared with those treated with deltamethrin alone (mortality: 0-6.70%). Furthermore, the effect of cuticular thickness on the escape response of field mosquitoes was significant, that is, the escape response marginally increased inversely to cuticular thickness. By contrast, cuticular thickness was not significantly associated with knockdown or mortality percentage.
Conclusion: Irritant behavior in mosquitoes was significantly elicited by PBO synergism. PBO incorporating deltamethrin IRS or LLINs may be effective for controlling dengue fever vectors. © 2021 Society of Chemical Industry