Precision tests of CPT symmetry and Quantum coherence with entangled neutral K

The quantum interference between the decays of entangled neutral kaons is a very powerful tool for testing the quantum coherence of the entangled kaon pair state. The studied process $\phi\rightarrow K_SK_L\rightarrow\pi^+\pi^-\pi^+\pi^-$ exhibits the characteristic Einstein-Podolsky-Rosen correlations that prevent both kaons to decay into $\pi^+\pi^-$ at the same time. The newly published result is based on data sample collected with the KLOE detector at DA $\Phi$ NE and corresponds to an integrated luminosity of about 1.7 fb $^{-1}$ , i.e. to $\sim$ 1.7 $\times$ 10 $^9$ $\phi\rightarrow K_SK_L$ decays. From the fit to the observed time difference distribution of the two kaon decays, the decoherence and CPT violation parameters of various phenomenological models are measured. A stringent upper limit on the branching ratio of the $\phi \rightarrow K_S K_S , K_L K_L$ decay is also derived. Independently, the comparison of neutral meson transition rates between flavour and CP eigenstates allows direct and model independent tests of time-reversal T and CPT symmetries to be conducted, through ratios of rates of two classes of processes: $K_S K_L \to (\pi^{\pm}e^{\mp}\nu)(3\pi^0)$ and $K_S K_L \to (\pi^{+}\pi^{-})(\pi^{\pm}e^{\mp}\nu)$ . In addition to this a straightforward extension to the case of CPT symmetry is performed providing the first model independent test of CPT symmetry violation in transitions of neutral kaons.The quantum interference between the decays of entangled neutral kaons is a very powerful tool for testing the quantum coherence of the entangled kaon pair state. The studied process $\phi\rightarrow K_SK_L\rightarrow\pi^+\pi^-\pi^+\pi^-$ exhibits the characteristic Einstein-Podolsky-Rosen correlations that prevent both kaons to decay into $\pi^+\pi^-$ at the same time. The newly published result is based on data sample collected with the KLOE detector at DA$\Phi$NE and corresponds to an integrated luminosity of about 1.7 fb$^{-1}$ , i.e. to $\sim$ 1.7 $\times$ 10$^9$ $\phi\rightarrow K_SK_L$ decays. From the fit to the observed time difference distribution of the two kaon decays, the decoherence and CPT violation parameters of various phenomenological models are measured. A stringent upper limit on the branching ratio of the $\phi \rightarrow K_S K_S , K_L K_L$ decay is also derived. Independently, the comparison of neutral meson transition rates between flavour and CP eigenstates allows direct and model independent tests of time-reversal T and CPT symmetries to be conducted, through ratios of rates of two classes of processes: $K_S K_L \to (\pi^{\pm}e^{\mp}\nu)(3\pi^0)$ and $K_S K_L \to (\pi^{+}\pi^{-})(\pi^{\pm}e^{\mp}\nu)$. In addition to this a straightforward extension to the case of CPT symmetry is performed providing the first model independent test of CPT symmetry violation in transitions of neutral kaons.

International Conference on High Energy Physics (ICHEP)Nov 30, 20223 citations

Precision tests of Quantum Mechanics and CPT symmetry with entangled neutral kaons at KLOE

D. Babusci, M. Berlowski, C. Bloise +55 more

The quantum interference between the decays of entangled neutral kaons is studied in the process $ϕ\rightarrow K_S K_L \rightarrowπ^+π^-π^+π^-$ , which exhibits the characteristic Einstein--Podolsky--Rosen correlations that prevent both kaons to decay into $π^+π^-$ at the same time. This constitutes a very powerful tool for testing at the utmost precision the quantum coherence of the entangled kaon pair state, and to search for tiny decoherence and CPT violation effects, which may be justified in a quantum gravity framework. The analysed data sample was collected with the KLOE detector at DA $Φ$ NE, the Frascati $ϕ$ -factory, and corresponds to an integrated luminosity of about 1.7 fb $^{-1}$ , i.e. to about $1.7 \times 10^9$ $ϕ\rightarrow K_S K_L$ decays produced. From the fit of the observed $Δt$ distribution, being $Δt$ the difference of the kaon decay times, the decoherence and CPT violation parameters of various phenomenological models are measured with a largely improved accuracy with respect to previous analyses. The results are consistent with no deviation from quantum mechanics and CPT symmetry, while for some parameters the precision reaches the interesting level at which -- in the most optimistic scenarios -- quantum gravity effects might show up. They provide the most stringent limits up to date on the considered models.The quantum interference between the decays of entangled neutral kaons is studied in the process $ϕ\rightarrow K_S K_L \rightarrowπ^+π^-π^+π^-$, which exhibits the characteristic Einstein--Podolsky--Rosen correlations that prevent both kaons to decay into $π^+π^-$ at the same time. This constitutes a very powerful tool for testing at the utmost precision the quantum coherence of the entangled kaon pair state, and to search for tiny decoherence and CPT violation effects, which may be justified in a quantum gravity framework. The analysed data sample was collected with the KLOE detector at DA$Φ$NE, the Frascati $ϕ$-factory, and corresponds to an integrated luminosity of about 1.7 fb$^{-1}$, i.e. to about $1.7 \times 10^9$ $ϕ\rightarrow K_S K_L$ decays produced. From the fit of the observed $Δt$ distribution, being $Δt$ the difference of the kaon decay times, the decoherence and CPT violation parameters of various phenomenological models are measured with a largely improved accuracy with respect to previous analyses. The results are consistent with no deviation from quantum mechanics and CPT symmetry, while for some parameters the precision reaches the interesting level at which -- in the most optimistic scenarios -- quantum gravity effects might show up. They provide the most stringent limits up to date on the considered models.

arXiv:2111.04328Nov 8, 20212 citations

Quantum coherence and CPT symmetry tests in the neutral kaon system at KLOE

ANTONIO DI DOMENICO

The neutral kaon system offers a unique possibility to perform fundamental tests of CPT invariance, as well as of the basic principles of quantum mechanics. The most recent limits obtained by the KLOE experiment at the DAΦNE e + e − collider on several kinds of possible CPT violation and decoherence mechanisms, which in some cases might be justified in a quantum gravity framework, are reviewed. No deviation from the expectations of quantum mechanics and CPT symmetry is observed, while the precision of the measurements, in some cases, reaches the interesting Planck scale region. Finally, prospects for this kind of experimental studies at KLOE-2 are presented.The neutral kaon system offers a unique possibility to perform fundamental tests of CPT invariance, as well as of the basic principles of quantum mechanics. The most recent limits obtained by the KLOE experiment at the DAΦNE e + e − collider on several kinds of possible CPT violation and decoherence mechanisms, which in some cases might be justified in a quantum gravity framework, are reviewed. No deviation from the expectations of quantum mechanics and CPT symmetry is observed, while the precision of the measurements, in some cases, reaches the interesting Planck scale region. Finally, prospects for this kind of experimental studies at KLOE-2 are presented.

International Conference on Kaon Physics (KAON)Feb 1, 20100 citations

The quantum interference between the decays of entangled neutral kaons is a very powerful tool for testing the quantum coherence of the entangled kaon pair state. The studied process

\phi\rightarrow K_SK_L\rightarrow\pi^+\pi^-\pi^+\pi^-

exhibits the characteristic Einstein-Podolsky-Rosen correlations that prevent both kaons to decay into

\pi^+\pi^-

at the same time. The newly published result is based on data sample collected with the KLOE detector at DA

\Phi

NE and corresponds to an integrated luminosity of about 1.7 fb

^{-1}

, i.e. to

\sim

1.7

\times

^9

\phi\rightarrow K_SK_L

decays. From the fit to the observed time difference distribution of the two kaon decays, the decoherence and CPT violation parameters of various phenomenological models are measured. A stringent upper limit on the branching ratio of the

\phi \rightarrow K_S K_S , K_L K_L

decay is also derived. Independently, the comparison of neutral meson transition rates between flavour and CP eigenstates allows direct and model independent tests of time-reversal T and CPT symmetries to be conducted, through ratios of rates of two classes of processes:

K_S K_L \to (\pi^{\pm}e^{\mp}\nu)(3\pi^0)

and

K_S K_L \to (\pi^{+}\pi^{-})(\pi^{\pm}e^{\mp}\nu)

. In addition to this a straightforward extension to the case of CPT symmetry is performed providing the first model independent test of CPT symmetry violation in transitions of neutral kaons.

The quantum interference between the decays of entangled neutral kaons is studied in the process

ϕ\rightarrow K_S K_L \rightarrowπ^+π^-π^+π^-

, which exhibits the characteristic Einstein--Podolsky--Rosen correlations that prevent both kaons to decay into

π^+π^-

at the same time. This constitutes a very powerful tool for testing at the utmost precision the quantum coherence of the entangled kaon pair state, and to search for tiny decoherence and CPT violation effects, which may be justified in a quantum gravity framework. The analysed data sample was collected with the KLOE detector at DA

Φ

NE, the Frascati

ϕ

-factory, and corresponds to an integrated luminosity of about 1.7 fb

^{-1}

, i.e. to about

1.7 \times 10^9

ϕ\rightarrow K_S K_L

decays produced. From the fit of the observed

Δt

distribution, being

Δt

the difference of the kaon decay times, the decoherence and CPT violation parameters of various phenomenological models are measured with a largely improved accuracy with respect to previous analyses. The results are consistent with no deviation from quantum mechanics and CPT symmetry, while for some parameters the precision reaches the interesting level at which -- in the most optimistic scenarios -- quantum gravity effects might show up. They provide the most stringent limits up to date on the considered models.