Uncommon Descent Serving The Intelligent Design Community

Rob Sheldon: What that hot new quantum experiment really showed

arroba Email

The experiment is To catch and reverse a quantum jump mid-flight, which suggests that quantum leaps take place in time (they are not extraordinary physics or unpredictable). “ Researchers were able to predict a kind of atomic behavior called a quantum jump and even reverse the jump in a new experiment on an artificial atom. Such research could bring up bigger questions about the nature of physics and could have important implications for improving quantum computers that rely on the rules of quantum mechanics in order to function.” (Gizmodo, June 3, 2019)

Recently, we heard a theoretical physicist dismiss its significance.

The Long Ascent: Genesis 1â  11 in Science & Myth, Volume 1 by [Sheldon, Robert]

Now, experimental physicist Rob Sheldon, our physics color commentator and author of Genesis: The Long Ascent, writes to say:

No, nothing dramatic happened to the universe.

The crystal radio, using a diode, enabled every teenager to assemble a radio in his room and tune in to one of the 3 radio stations in the United States. But he had to wear headphones because the volume was so quiet. The triode was capable of amplifying those signals, and very soon the Grateful Dead’s tube amps were destroying the eardrums of 3 generations of teenagers.

In the same way, qubits incorporate QM effects, and marvellous things have been done with 2 level systems. I mentioned QM computers before, which do things like decode the 128 or 256 digit encryption standards using in secure communications.

Another more common two-level QM encryption method uses 4 entangled photons in two pairs. One pair is up/down (st.andrew cross) the other is diagonal (st.george cross), and the receivers consist of two pairs of polarizing beam splitters directing photons into 4 detectors. Starting with 5 million entangled photons per second, they can transmit up to 1000 bits per second, which is about half the speed of the 2400 baud modem I purchased to work at home on my PhD thesis some 30 years ago.

So why do QM encryption?

Because the NSA can’t intercept the message. That’s why the Chinese “Micius” satellite using Univ of Austria technology was able to digitally connect two cities in China in 2017 using a snoop-proof satellite digital channel. It took about $100M of components to do this, and like I said, was slower than my 1988 USRobotics modem.

What this recent paper with a qutrit experiment shows, is that it is possible to do QM communication or QM computing at high volume and high speed. No need to wear headphones.

Readers can relax.

See also: Theoretical physicist: Recent claim about big quantum mechanics find is “silly” Maybe the main thing to see here is that lots of people would love to falsify or tame quantum mechanics, the way they would like to falsify the Big Bang or fine-tuning and it won’t be their fault for lack of trying.

Follow UD News at Twitter!

I'm looking at Zlatko Minev's Feb 2019 Arxiv paper--200 pages long. I'll see what I can make of it. However, there are those saying that Minev's experiment shows nothing new, that we're dealing with basic QM and the results are merely the residue of what has been known for a long time: decoherence "collapses" the wave-function. Phillip Ball wrote a book on all of this last year, "Beyond Wierd"--I'm reading it now, and it has won the Physics Book of the Year award. He must know something since the entire book is about interpretation of QM. And he thinks this is significant. So do I. We're seeing something more than mere "decoherence." Decoherence is roughly understood as the local environment absorbing information within the wave function. Well, if the quantum 'jump' is essentially the work of decoherence, then the 'beginning' of the 'jump' is the beginning of decoherence. So, how exactly, is decoherence reversed?--because that is what they do. This reversal of decoherence should not just be hand-waved away. And the entire experiment is the result of a prediction made by quantum trajectories theory (Howard Carmichael). This, too, should capture some interest on the part of those who follow QM. I'll report back if I find something in Minev's longer paper. PaV
AS78, in relevant energy/state jumps, there is no definable trajectory. This is connected to observability and wave vs particle issues at first level. KF kairosfocus
Not important, but the Saint Andrews cross is the one which is diagonal. No true Scotsman would make a mistake like that. Belfast
So did they show that quantum mechanics happens in real time I am not quite understanding the significance of all of this. Secondly was the experiment nothing more than a simulation with an artificial atoms, like what they did with barium partials trying to replicate a monopole? That is kind of important because that could explain their results as it is not the actual quantum leap affect taking place but a simulation AaronS1978

Leave a Reply