My daughter from Portland texted me this interesting aritcle: my housekeeper asked about this and I mentioned how we didn't have hand held lasers yet because they haven't been microminaturized yet and we don't have batteries small enough and powerful enough to power really hand held laser guns, but ships do have lasers that can bring down a plane and disable a ship by "cooking" the plane or ship at present but it takes about one minute with the laser from one ship onto another to do this.
The same appears true regarding teleportation which appears at this stage is more like faxing a photon to a satellite in space more than anything else. But, faxing human beings? what would that do? Would the copy faxed into space contain the same memories of the original human? And then what do you do with the copy when you are through with it? Do the original human and the copy human fight to see which one stays alive or do they both live on with many copies of ourselves all over the place throughout time and space?
begin quote from:
Teleportation: Photon particles today, humans tomorrow? - BBC.com
www.bbc.com/news/science-environment-40594387
Jul 14, 2017 - Chinese scientists say they have "teleported" a photon particle from the ground to a satellite orbiting 1,400km (870 miles) away.
Teleportation: Photon particles today, humans tomorrow? - YouTube
https://www.youtube.com/watch?v=-sgBncypc08
Jul 14, 2017 - Uploaded by Interesting world
Chinese scientists say they have "teleported" a photon particle from the ground to a satellite orbiting ... Teleportation: Photon particles today, humans tomorrow?
Chinese scientists
say they have "teleported" a photon particle from the ground to a
satellite orbiting 1,400km (870 miles) away.
For many, however,
teleportation evokes something much more exotic. Is a world previously
confined to science fiction now becoming reality?Well, sort of. But we are not likely to be beaming ourselves to the office or a beach in the Bahamas anytime soon. Sorry.
How does it work?
Simply put, teleportation is transmitting the state of a thing rather than sending the thing itself.Some physicists give the example of a fax machine - it sends information about the marks on a piece of paper rather than the paper itself. The receiving fax machine gets the information and applies it to raw material in the form of paper that is already there.
Instead, it relies on a phenomenon known as quantum entanglement.
What is quantum entanglement?
Indeed. The phenomenon arises when two particles are created at the same time and place and so effectively have the same existence.This entanglement continues even when the photons are then separated. It means that if one of the photons changes, the other photon in the other location changes too.
Prof Sandu Popescu, from Bristol University, has been working on quantum entanglement since the 1990s.
"Even then people were thinking about Star Trek. But we are talking about sending the state of a single particle, not the billions of billions of billions of particles that form a person," he says.
"If you are thinking about a remote planet, first you would have to exchange billions of entangled pairs of particles and then you have to send other information as well. This is highly non-trivial. One should not get excited by that."
How do I teleport a particle?
Let's go back to our two entangled particles. If a third particle interacts with the first entangled particle, the change that occurs in the entangled particle is mirrored in its twin.So the twin contains information about the third particle and effectively takes on its existence.
Sounds great, what's the problem?
It has been impossible to create a long-distance link between two entangled particles because an entangled photon can only travel about 150km down a fibre-optic channel before becoming absorbed.Read more:
- Quantum computing: Game changer or security threat?
- 'Dead or alive' cat in physics top 10
- Justin Trudeau meets quantum challenge
- The pro-ballerina and quantum physicist
What has the Chinese team achieved?
They created 4,000 pairs of quantum-entangled photons per second at their laboratory in Tibet and fired one of the photons from each pair in a beam of light towards a satellite called Micius, named after an ancient Chinese philosopher.Micius has a sensitive photon receiver that can detect the quantum states of single photons fired from the ground. Their report - published online - says it is the first such link for "faithful and ultra-long-distance quantum teleportation".
"It is a very nice experiment - I would not have expected everything to have worked so fast and so smoothly," says Professor Anton Zeilinger from the University of Vienna, who taught Chinese lead scientist Pan Jianwei.
If you can't teleport people, why is it exciting?
The main goal for quantum teleportation at present is the creation of unhackable communications networks."The laws of nature offer protection," says Prof Popescu. "If someone was to intercept the information you could detect it because whenever you try to observe a quantum system you disturb it."
"It is the first quantum internet. Data rates are low so it is not useful for the current internet. But it is useful for refreshing the quantum key used to send encrypted information," Prof Zeilinger says.
The quantum network could be used for sensitive financial or electoral information, says Professor Ian Walmsley from Oxford University.
"There are significant barriers still to overcome. But this is how transformative change begins," he says.
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