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Quantum teleportation is useless
(Fig.1) Even in 2025, quantum teleportation can send fragile photons over only 270 meter, which is far from practical communication or internet contrary to hypes.
Quantum teleportation is useless, can only send information of measured polarization of classical light (or photons ) by ordinary classical communication with No quantum mechanics or superluminal entanglement.
Quantum teleportation uses very weak (classical) light or a photon as quantum information that is too easily lost (= and Not allowed to be copied or amplified due to stupid quantum mechanical rule ), so cannot be sent over practically-long distance.
This-Challenges and limitations (2026) say -- Useless quantum teleportation
"One key hurdle is distance: photon loss in optical fiber limits direct transmission to about 100 kilometers."
"Quantum teleportation rates over real-world fiber are still quite low, typically in the range of hertz to kilohertz.... it's far too slow to support distributed quantum cloud computing"
↑ Practical quantum internet or communication, which needs all information (= photons ) to be sent to destination with zero photon loss, is impossible forever.
This hyped news (2025) ↓
1st-paragraph says -- Overhyped news
"An international research team involving Paderborn University has achieved a crucial breakthrough on the road to a quantum internet (= hype ). For the first time ever, the polarization state of a single photon emitted from a quantum dot was successfully teleported to another physically separated quantum dot."
2nd-paragraph says -- Just 270 m useless teleportation
"This is a particularly vital step for future (= still unrealized ) quantum communication networks.... the scientists used a 270m free-space optical link for their experiments" ← Just 270 meter is far from practical internet or communication.
9th-paragraph says -- Error-prone teleportation
"The achieved teleportation state fidelity (i.e., the quality in which quantum states are preserved during teleportation) reaches up to 82 ± 1%, " ← 18% error rate, which is impractical communication.
This-2nd-last-paragraph says (2025)
"For now, the quantum networking reality remains firmly grounded in experimental metro deployments - exciting, but still a far cry from a quantum internet."
↑ This research paper (= this-last-link ) ↓
p.3-Fig.1 says -- Just 270 meter = useless
"the X1 photon from QD1 (= Node-1 )... QD2 (= Nodde-2 ) emits a polarization-entangled biexciton-exciton photon pair, XX2 and X2 (= with the same polarization )... A BSM (= Alice measuring polarizations of two lights from nodes-1 and 2 ) is performed in Node 2, while XX2 is sent to Node 3 (= Bob ),.. through a 270 m (= too short ) free-space optical link"
p.4-Fig.2b (and p.6-right-last ) shows -- Two polarized classical lights
This OD2 in node-2 emitted two lights with the same polarizations (= VV = vertical-vertical or HH = horizontal-horizontal ) that have nothing to do with superluminal quantum entanglement link.
p.4-right-1st-paragraph says -- 3-photon coincident measurement
". At
the same time, the XX2 photons undergo a polarization measurement
in Node 2, where we collect the three-fold coincidences among their
detection and X1-X2 coincidence" ← 3 photons of X1 (= from OD1 in node-1 ), X2, XX2 (= from OD2 in node-2 ) must be measured simultaneously, which is called three-fold coincidence.
p.5-left-lower says -- Massive information loss
"XX2 photons are
sent through the quantum channel and measured in Node 3, in the
Fermi building of Sapienza. This operation presents many challenges,
including the presence of substantial losses ( almost 90% of the signal is
lost through the channel )"
p.6-right-middle says -- Massive photon loss
"yielding an estimated rate of
teleportation three-fold events of 7.8 × 10−6 per prepared photon" ← So the probability of detecting 3 photons coincidentally is very low = only 0.000078 due to massive photon loss ( this-p.3-2.1 ).
↑ So even this recent teleportation experiment in 2025 could send fragile lights or photons over only 270 meter (via classical communication ) due to massive loss of photons, which is useless, far from the overhyped quantum internet.
This-Inside brief and last-paragraph (2024) say -- Just 30 km
" the team successfully transmitted quantum information (= fragile photons or weak light ) alongside high-speed Internet signals over a 30-kilometer cable." ← Just 30km is useless, far from practical network.
"This work represents a significant step (= still unrealized, infinite steps will be needed ) toward integrating quantum technology"
↑ This research paper ↓
Fig.3 shows -- Easy photon loss
Only about 50 photons per 900s could be counted due to massive photon loss (= 4 photons must be detected coincidentally in the four related photodetectors to validate teleportation as 4-fold-coincidences ).
↑ So quantum teleportation is useless, can send fragile photons (= weak light ) over only 30km at very slow pace (= only 50 photon information counts per 900s ), which is completely useless for quantum internet or communication, contrary to a lot of overhyped fake news.
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