Quantum internet, network is overhyped, useless forever.

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Quantum internet is useless forever.
Quantum teleportation is meaningless

(Fig.1)  ↓ Extremely low efficiency of impractical quantum internet and memory.

Quantum teleportation is just measurement of lights, irrelevant to sending quantum information.

The 1st, 7th, last paragraphs of this hyped news (7/21/2025) say
"Quantum teleportation... could be central to the realization of a so-called "quantum internet, a version of the internet that enables the safe and instant transmission of quantum information"  ← wrong, quantum teleportation can send only classical information.

"These include an Input state preparation; an EPR-source to generate entangled photon pairs (= just two classical lights ) from an integrated photonic chip, a Bell-state measurement and a quantum memory based on erbium ion ensembles."

"As part of their next studies, the researchers plan to (= still unrealized ) focus on improving the performance of the erbium ion-based solid-state memory.. they would like to extend its storage times and improve the efficiency (= because still bad efficiency ) with which it stores quantum information."

Most quantum information (= photons ) was lost in impractical quantum internet (= still far from internet ) and memory.

↑ This research paper ↓

p.1-right-1st-paragraph says "we send the idler photon to Alice, who performs the joint Bell-state measurement (BSM) on both idler and input photons obtained from attenuated laser"

"Thirdly, the signal photon is sent to the 167Er3+ ions quantum memory,... stored for more than 2 µs (= Er3+ ion stored the input photon as excited-energy state for only very short 2μs, which is an impractical memory )"

p.4-left-1st-paragraph says "The overall storage efficiency is about 1.1% ( this-p.2-Efficienty )."  ← So this quantum memory (= Er3+ ions ) lost 99.9% stored light energy (= quantum information ), completely useless.

↑ This-p.2-right-last says "The memory efficiency is defined as the ratio of the energy of the retrieved signal to the input signal"  ← Only 1.1% of the input light signal was retrieved (= 99.9% of light information was lost )

Detecting 3 photons coincidentally only 2.5 times per 300 seconds due to massive photon loss, which cannot be used for quantum internet.

This-research paper-p.7-Fig.S1 and p.10-Fig.S5 shows Three-fold coincidences are just 2.5 per 300s.

↑ It means the rate of 3 detectors detecting 3 photons (= lights ) simultaneously ( this-p.12-Figure.5,   ) is just 2.5 times per 300 seconds due to massive photon loss.

↑ Detecting 3 photons only 2.5 times per 300 seconds is too slow and completely impractical as (quantum) internet or communication, contrary to hypes.

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