Schrodinger's cat - I just don't get it....
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Soldato
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The particles behaved differently when they were observed i.e. measured, which is really interesting
Soldato
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From experience, anyone who can get a cat into a box against its will is probably in a very agitated state and an unreliable observer, at best.
Yea, that's the likely explanation imo. When a particle is 'entangled' it can seem to us to be far apart in our 3 spatial dimensions, but could still be directly connected in a higher dimension hence why altering 1 particle immediately affects the other.
OP: If you really want to understand what it's all about, I can recommend reading 'Six Easy Pieces' by Richard Feynman. It's a superb intro some very complicated areas of physics, written in a way that even I managed to understand.
Yes Feynman is no only a brilliant scientist, but has a rare ability to articulate complex theories in a way anyone can understand.
Richard Feynman: Quantum Mechanical View of Reality 1
In this series of 4 lectures, Richard Feynman introduces the basic ideas of quantum mechanics. The main topics include: the basics, the Heisenberg’s uncertai...
www.youtube.com
Deleted User 298457
Deleted User 298457
Google it- but I am pretty sure it is a fundamental physics problem, i.e. it is impossible.
I read something recently about a method being worked on to measure (extract quantum information from) a system without collapsing the quantum state.
A google brings up this, which might have been it.
How Properties of Mechanical Quantum Systems Can Be Measured Without Destroying the Quantum State
New experimental work establishes how quantum properties of mechanical quantum systems can be measured without destroying the quantum state. Systems in which mechanical motion is controlled at the level of individual quanta are emerging as a promising quantum-technology platform. New experimental
scitechdaily.com
Deleted User 298457
Deleted User 298457
Interesting - if this moved beyond theoretically I am pretty sure this destroys the Quantum Cryptography paradigm. (@NickK ?)I read something recently about a method being worked on to measure (extract quantum information from) a system without collapsing the quantum state.
A google brings up this, which might have been it.
How Properties of Mechanical Quantum Systems Can Be Measured Without Destroying the Quantum State
New experimental work establishes how quantum properties of mechanical quantum systems can be measured without destroying the quantum state. Systems in which mechanical motion is controlled at the level of individual quanta are emerging as a promising quantum-technology platform. New experimentalscitechdaily.com
The store that's open and/or closed 
Yes within reason. The idea is to use quantum sources to generate randomness that is unbiased (thus truly random) and completely private (unknown from the point of creation to use). Randomness and total privacy defines the quality of the key used for the cryptographic maths used to encrypt your data.
1. A quantum source is inherently free from bias and therefore random (this means you need to know the device and prove it's not tampered with)
2. Using bell theorem you can detect, statistically, if the random numbers come originally from a classical source or a quantum source. (yet the source could be recorded and replayed as a known sequence).
3. IIRC using the noise characterisation you can detect if more than one entanglement exists - thus you can detect if a quantum source is private.
Now if you can measure a quantum device without being detectable then it is not private. Thus the random numbers used for the keys for the cryptography may be known to attackers.
Most detection derives from energy being lost to the detection causing an imbalance (thus you can detect it either directly or indirectly). So if a quantum state is is not changed (assuming no energy lost) then it would be difficult to detect.
The other part of quantum cybersecurity is the mathematical problems used to encrypt - those wouldn't be affected. You could even use a real RNG (non 'quantum' but natural - ie lava lamps, radioactive decay etc) with them but you don't know the quality (and secrecy) of the randomness generated. For example - think of a radioactive source causing randomness through the half-life.. you could use a smoke detector emotions to cause false detection ticks to bias and thus gain knowledge about the result (you could simply swamp it and force all the numbers to 1.. but that would be easy to detect).
TL;DR - only part of the puzzle, quantum randomness is likely to be the same quality as TrueRNG but the benefit of quantum has been to be able to detect tampering which may be at risk. Until someone comes up with yet another way to detect that.. the cat and mouse game continues..
If the system managed to not leak energy as information.. then it would also be breaking a fundamental law of physical (ie energy conservation). (HINT: it needs a shed load of peer review)
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Deleted User 298457
Deleted User 298457
Mrk will sell you his unwashed one for 10x
oh i like that a lot - does it have the 'i'm dead cat' on the back or is that a separate tshirt?!The store that's open and/or closed
Soldato
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The problem of superposition in my mind simply means we don't know what the real mechanism is. Particles or waves, yes characteristics of both are observed, but perhaps the real answer is its neither and something else is happening which explains both sets of observations.
I started doing physics at uni in 1998 and left the course after a year, for two reasons: the first was it was bloody hard, and the second was that it quickly became apparent to me that these theories are likely to be completely wrong and something completely different is actually happening and no-one knows what it is.
I started doing physics at uni in 1998 and left the course after a year, for two reasons: the first was it was bloody hard, and the second was that it quickly became apparent to me that these theories are likely to be completely wrong and something completely different is actually happening and no-one knows what it is.
It glows in the dark, so that's what you see in the dark
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