Discussion:
Quantum mystics
(too old to reply)
Jeroen Belleman
2024-06-09 18:46:53 UTC
Permalink
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.

I feel a rant bubbling up!

The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.

He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.

He's in it for the money and the fame. Grrr. And he's one of
many, too.

Jeroen Belleman
Phil Hobbs
2024-06-09 19:04:32 UTC
Permalink
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
One of many over the years, starting with Bohr. Among the others are David
Bohm, Fritjof Capra, and Brian Josephson.

They’re distinguished from the mechanistic materialist majority merely by
being wrong in the opposite direction.

Almost all physicists make horrible philosophers, some worse than others.
It’s an occupational hazard.

When Tommy’s mum doesn’t make him clean up his own room because he’s so
smart, Tommy needs an unusually level head to avoid becoming a conceited
ass.

Cheers

Phil Hobbs
--
Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC /
Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics
bitrex
2024-06-09 20:04:27 UTC
Permalink
On 6/9/2024 2:46 PM, Jeroen Belleman wrote:

He did
Post by Jeroen Belleman
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact.
Sounds like stuff from the "stuff everyone knows" department.

Maybe one of those cases where the presenter has spent so much time at a
certain level they overestimate the background of the audience.
john larkin
2024-06-09 20:08:08 UTC
Permalink
On Sun, 9 Jun 2024 20:46:53 +0200, Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
Good so far!
Post by Jeroen Belleman
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
Light isn't packaged in discrete photons of measurable energy?

Of course you can't say much about a thing that has never been
detected. It's just a rumor.
Post by Jeroen Belleman
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement.
Do people still say "duh" ?
Post by Jeroen Belleman
For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
Most measurements, and the measuring instruments, are defined in
advance of the event. Calibrated even.
Post by Jeroen Belleman
He's in it for the money and the fame. Grrr. And he's one of
many, too.
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
Post by Jeroen Belleman
Jeroen Belleman
Martin Brown
2024-06-09 21:07:53 UTC
Permalink
Post by john larkin
On Sun, 9 Jun 2024 20:46:53 +0200, Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
Link please? It is impossible to comment without seeing his talk.
Post by john larkin
Post by Jeroen Belleman
I feel a rant bubbling up!
Good so far!
It was true when I was an undergraduate and it is still just as true
today that if you claim to fully understand quantum mechanics then you
don't fully understand quantum mechanics.
Post by john larkin
Post by Jeroen Belleman
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
Light isn't packaged in discrete photons of measurable energy?
It is a bit more nuanced than that. You can certainly show from metal
work functions that the energy they carry is quantised and also that for
very low photon densities such that only one photon can be in the
instrument at a time the diffraction pattern still occurs. That is
pretty conclusive evidence that QM is a real phenomena.

Likewise you can get diffraction patterns from silver ions or
buckyballs. I'm not sure what the current record mass is today.

We can haggle about mechanism and it is likely that a better theory will
eventually come along that is much less "action at a distance" than the
QM one we have now. In the same way that GR displaced Newtonian gravity.
Post by john larkin
Of course you can't say much about a thing that has never been
detected. It's just a rumor.
Everything that we observe has to be detected somehow.
It is possible for systematic errors to creep in. The speed of light
with error bars as a function of time is a salutary lesson on that.
Post by john larkin
Post by Jeroen Belleman
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement.
Do people still say "duh" ?
The intensity interferometer Hanbury-Brown & Twiss was a canonical
example of a QM prediction that almost no physicists believed at the
time until they actually made it work at Jodrell Bank. Today they can do
long(ish) baseline coherent optical interferometry up to the near IR.
Post by john larkin
Post by Jeroen Belleman
For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
Most measurements, and the measuring instruments, are defined in
advance of the event. Calibrated even.
Life gets tricky in relativistic QM but you can still get around it by
making the signals travel around loops and/or moving atomic clocks very
slowly to each measurement point. 5km long optical fibres are relatively
cheap...

"Simultaneous" is only well defined at a particular point in space-time.
Post by john larkin
Post by Jeroen Belleman
He's in it for the money and the fame. Grrr. And he's one of
many, too.
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
--
Martin Brown
john larkin
2024-06-09 23:56:12 UTC
Permalink
On Sun, 9 Jun 2024 22:07:53 +0100, Martin Brown
Post by Martin Brown
Post by john larkin
On Sun, 9 Jun 2024 20:46:53 +0200, Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
Link please? It is impossible to comment without seeing his talk.
Plug his name into Youtube and his Nobel speech pops up.
Post by Martin Brown
Post by john larkin
Post by Jeroen Belleman
I feel a rant bubbling up!
Good so far!
It was true when I was an undergraduate and it is still just as true
today that if you claim to fully understand quantum mechanics then you
don't fully understand quantum mechanics.
I suspect that aspects of this universe, big and small, can never be
understood by our brains. We can experiment, confirm, and accept.

The split-beam interferometer was designed specifically to mess with
our heads.
Jeroen Belleman
2024-06-10 14:45:04 UTC
Permalink
On 6/10/24 01:56, john larkin wrote:
[...]
Post by john larkin
The split-beam interferometer was designed specifically to mess with
our heads.
Was it? I think it behaves exacly like you'd expect from
a wave phenomenon observed with quantized detectors.

Jeroen Belleman
Martin Brown
2024-06-10 17:03:32 UTC
Permalink
Post by Jeroen Belleman
[...]
Post by john larkin
The split-beam interferometer was designed specifically to mess with
our heads.
Was it? I think it behaves exacly like you'd expect from
a wave phenomenon observed with quantized detectors.
But the wave phenomena in some experiments (aka wavefunction) can belong
to comparatively heavy objects that we would normally think of as
classical particles. Indeed we can even image the molecules used at
atomic level with scanning tunnelling microscopes.

I'm pretty sure they have diffracted buckyballs through Young's slits. I
think the record for complexity is still held by a fluorinated porphyrin
~10k amu 800+ atoms and efforts are underway to diffract a small virus.

More info on Arxiv here : https://arxiv.org/pdf/1310.8343

Experimentally it is quite a tour de force!

Physical intuition tends to break down when you have a superposition of
quantum states involved. Attempting to know which slit a particle
actually went through destroys the interference pattern and experiments
using ultra low flux levels with just a single photon in at any one time
still show a diffraction pattern. QM is decidedly counter intuitive.

Explores all available paths mathematics gets the right results but I
can't help feeling that there is a way to avoid the action at a distance
implied by quantum entanglement when we get all of the physics correct.

I didn't think his talk was all that outrageous. A bit over simplified
perhaps but then avoiding almost all of the maths that is inevitable.
--
Martin Brown
Jeroen Belleman
2024-06-10 21:43:38 UTC
Permalink
Post by Martin Brown
Post by Jeroen Belleman
[...]
Post by john larkin
The split-beam interferometer was designed specifically to mess with
our heads.
Was it? I think it behaves exacly like you'd expect from
a wave phenomenon observed with quantized detectors.
But the wave phenomena in some experiments (aka wavefunction) can belong
to comparatively heavy objects that we would normally think of as
classical particles. Indeed we can even image the molecules used at
atomic level with scanning tunnelling microscopes.
I'm pretty sure they have diffracted buckyballs through Young's slits. I
think the record for complexity is still held by a fluorinated porphyrin
~10k amu 800+ atoms and efforts are underway to diffract a small virus.
More info on Arxiv here : https://arxiv.org/pdf/1310.8343
University of Vienna, Zeilinger's fief, again. I'll have a closer
look to see what tricks they played.
Post by Martin Brown
Experimentally it is quite a tour de force!
Physical intuition tends to break down when you have a superposition of
quantum states involved. Attempting to know which slit a particle
actually went through destroys the interference pattern and experiments
using ultra low flux levels with just a single photon in at any one time
still show a diffraction pattern. QM is decidedly counter intuitive.
Explores all available paths mathematics gets the right results but I
can't help feeling that there is a way to avoid the action at a distance
implied by quantum entanglement when we get all of the physics correct.
I didn't think his talk was all that outrageous. A bit over simplified
perhaps but then avoiding almost all of the maths that is inevitable.
Over-simplified to the point of being devoid of meaning, indeed.

Jeroen Belleman
Martin Brown
2024-06-11 08:01:45 UTC
Permalink
Post by Jeroen Belleman
Post by Martin Brown
Experimentally it is quite a tour de force!
Physical intuition tends to break down when you have a superposition
of quantum states involved. Attempting to know which slit a particle
actually went through destroys the interference pattern and
experiments using ultra low flux levels with just a single photon in
at any one time still show a diffraction pattern. QM is decidedly
counter intuitive.
Explores all available paths mathematics gets the right results but I
can't help feeling that there is a way to avoid the action at a
distance implied by quantum entanglement when we get all of the
physics correct.
I didn't think his talk was all that outrageous. A bit over simplified
perhaps but then avoiding almost all of the maths that is inevitable.
Over-simplified to the point of being devoid of meaning, indeed.
That is the problem with popular science lectures about QM. This one - a
Nobel prize lecture by Serge Heroche from 2012 is a lot more meaty and
the experimental techniques they used and perfected are breathtakingly
cunning. The audience has quite a few famous physicists in it.

He is wonderfully self effacing and shares the credit for the success of
his experiments very generously with his co-winner many collaborators,
his team and graduate students.

Non destructive sensing of single atom quantum states is incredibly
impressive! I didn't know until I saw that talk that the Schrodinger's
cat wavefunction has been experimentally verified.

Basically he has constructed a real life particle in a box experiment!

It took ultracold superconducting hyper polished mirrors to realise it.
--
Martin Brown
bitrex
2024-06-10 00:00:52 UTC
Permalink
Post by Martin Brown
Post by john larkin
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
The general public tends to be exceptionally mathematics-averse. Even
many people with advanced degrees in fields outside the hard sciences
tend to be pretty math-averse.

There's a modest subset of the population that's math-averse but is not
averse to trying to learn something qualitative about quantum physics or
the Riemann Hypothesis or some other mathematical aspect of the hard
sciences and enjoy the satisfaction of feeling like they know
_something_ more than they went in, even if the details aren't within
their grasp.

In contrast to the rather large subset of the population, even people
with college degrees, who are OK with not knowing the first thing about
such topics, and tend to prefer it that way.
john larkin
2024-06-10 00:15:59 UTC
Permalink
Post by bitrex
Post by Martin Brown
Post by john larkin
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
The general public tends to be exceptionally mathematics-averse. Even
many people with advanced degrees in fields outside the hard sciences
tend to be pretty math-averse.
People are different. I like it that way.

Most people don't need much math. Hardly anyone uses algebra, much
less number theory or calculus. They manage to buy enough paint for
the living room, or enough chickens to feed a family gathering.

Simulation has taken a lot of math out of engineering. I do only
primitive algebra and no calculus. We have used some number theory to
design DDSs and frequency synthesizers and such.
Jeff Layman
2024-06-10 07:18:51 UTC
Permalink
Post by bitrex
Post by Martin Brown
Post by john larkin
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
The general public tends to be exceptionally mathematics-averse. Even
many people with advanced degrees in fields outside the hard sciences
tend to be pretty math-averse.
Absolutely correct. I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small". I learnt to use the formulae for differentiation
and integration and passed my exams, but my eyes clouded over then as
far as abstract mathematical concepts are concerned, and they've never
cleared! It's quite possible that I have to be able to imagine most
things to understand them, and, to me, mathematics is just not within my
imagination.
Post by bitrex
There's a modest subset of the population that's math-averse but is not
averse to trying to learn something qualitative about quantum physics or
the Riemann Hypothesis or some other mathematical aspect of the hard
sciences and enjoy the satisfaction of feeling like they know
_something_ more than they went in, even if the details aren't within
their grasp.
I'm interested in almost anything scientific, even if I can't understand
it. Perhaps it's better that way - I don't have to see the wood for the
trees!
Post by bitrex
In contrast to the rather large subset of the population, even people
with college degrees, who are OK with not knowing the first thing about
such topics, and tend to prefer it that way.
--
Jeff
Liz Tuddenham
2024-06-10 08:14:19 UTC
Permalink
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk
Jeff Layman
2024-06-10 08:44:08 UTC
Permalink
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
:-)

More years ago than I care to remember I was coming back from the USA in
business-class and sitting next to me was a woman dripping with
jewellery. She was using a laptop and I could see she was writing
horoscopes, from the Leo, Virgo, Scorpio, etc headings on the screen.
Under them she was typing the details of each one for the day. Not only
was she not referring to anything as to what astrologers might consider
relevant for that day and that sign of the Zodiac, but she was cutting
and pasting between them at random!

I assumed she was someone well known for writing horoscopes and they
were syndicated. It sure seemed to pay well from the jewellery she had!
--
Jeff
john larkin
2024-06-10 14:14:34 UTC
Permalink
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
Interesting electronics is nonlinear. I recall some college professor
mumbling about solving nonlinear differential equations but it wasn't
encouraging.

Having some gut-level feeling for integration and differentiation and
diff equations and initial conditions and control theory is good, but
Spice can do the actual work.

I taught a course once on dynamic systems. The final assignment was to
write a Basic program to simulate refilling a toilet tank after a
flush. Surprisingly, everybody got it right.
Bill Sloman
2024-06-10 15:09:51 UTC
Permalink
Post by john larkin
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
Rubbish.
Post by john larkin
Interesting electronics is nonlinear.
Also rubbish. Most electronics is non-linear, but the interesting stuff
does tend to be linear in the regions of interest.
Post by john larkin
I recall some college professor mumbling about solving nonlinear differential equations but it wasn't
encouraging.
Not encouraging enough to get your attention.
Post by john larkin
Having some gut-level feeling for integration and differentiation and
diff equations and initial conditions and control theory is good, but
Spice can do the actual work.
Perhaps.
Post by john larkin
I taught a course once on dynamic systems. The final assignment was to
write a Basic program to simulate refilling a toilet tank after a
flush. Surprisingly, everybody got it right.
You kept the course down to a level that you could understand.
--
Bill Sloman, Sydney
--
This email has been checked for viruses by Norton antivirus software.
www.norton.com
Liz Tuddenham
2024-06-10 17:00:10 UTC
Permalink
Post by Bill Sloman
Post by Liz Tuddenham
Calculus is to arithmetic what astrology is to astronomy.
Rubbish.
Do you have any friends?
--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk
john larkin
2024-06-10 18:50:54 UTC
Permalink
Post by Liz Tuddenham
Post by Bill Sloman
Post by Liz Tuddenham
Calculus is to arithmetic what astrology is to astronomy.
Rubbish.
Do you have any friends?
He certainly doesn't have a job.
Bill Sloman
2024-06-11 12:10:02 UTC
Permalink
Post by john larkin
Post by Liz Tuddenham
Post by Bill Sloman
Post by Liz Tuddenham
Calculus is to arithmetic what astrology is to astronomy.
Rubbish.
Do you have any friends?
He certainly doesn't have a job.
At age 81 it's certainly hard to persuade the personnel department that
you have anything to offer. Being treasurer of the NSW branch of the
IEEE is role, rather than a job, because I don't get paid for it.
--
Bill Sloman, Sydney
--
This email has been checked for viruses by Norton antivirus software.
www.norton.com
Bill Sloman
2024-06-11 12:06:14 UTC
Permalink
Post by Liz Tuddenham
Post by Bill Sloman
Post by Liz Tuddenham
Calculus is to arithmetic what astrology is to astronomy.
Rubbish.
Do you have any friends?
Quite a few. None that feel the need to flattered.
--
Bill Sloman, Sydney
--
This email has been checked for viruses by Norton antivirus software.
www.norton.com
Bill Sloman
2024-06-10 15:02:14 UTC
Permalink
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
Rubbish. You can't have astrology without astronomy, but the conclusion
astrologers draw from astronomical events are total nonsense.

You can't have calculus without arithmetic, but calculus is just a
device that lets you get accurate arithmetic results with less
computation. Newton used it exactly that way. Leibniz

https://en.wikipedia.org/wiki/Gottfried_Wilhelm_Leibniz

did too, but he also spelled exactly how he was doing it which is why we
use his notation, rather Newton's.
--
Bill Sloman, Sydney
--
This email has been checked for viruses by Norton antivirus software.
www.norton.com
Jeroen Belleman
2024-06-10 15:55:47 UTC
Permalink
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
Now now, that's unjustified. Calculus is eminently useful
and perfectly rigorous.

Mathematics is a tool chest. Unfortunately, the way it's
taught, few people end up being able to use the tools.

Jeroen Belleman
john larkin
2024-06-10 18:52:40 UTC
Permalink
On Mon, 10 Jun 2024 17:55:47 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
Now now, that's unjustified. Calculus is eminently useful
and perfectly rigorous.
Mathematics is a tool chest. Unfortunately, the way it's
taught, few people end up being able to use the tools.
Jeroen Belleman
How often do you use real, symbolic calculus?

Solving differential equations?
Martin Brown
2024-06-10 19:16:10 UTC
Permalink
Post by john larkin
On Mon, 10 Jun 2024 17:55:47 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
Now now, that's unjustified. Calculus is eminently useful
and perfectly rigorous.
Mathematics is a tool chest. Unfortunately, the way it's
taught, few people end up being able to use the tools.
I'm not sure that it *is* the teaching. It is more a cultural thing. It
is OK to be "bad at maths" but not OK to have not read Shakespeare.

I blame the teaching for the appallingly high proportion of electronics
engineers that refuse to accept Special or General Relativity though.
Post by john larkin
Post by Jeroen Belleman
Jeroen Belleman
How often do you use real, symbolic calculus?
Not quite daily but more than once a week. These days I tend to throw a
lot of it at Maxima or Mathematica rather than do grunt work by hand.
Even so mechanical tools need guiding towards the right answer.

Both have some annoying features/quirks that you have to work around.
Post by john larkin
Solving differential equations?
Less frequently. Mostly I'm involved in finding faster rational
approximations to awkward non-linear equations or linearising things
that don't really want to play ball. The idea is to have a fast
approximation that is good enough to act as a seed value for a
NR/Halley/higher refinement step to always converge.

Much of that relies on calculus of variations which is another step
above the sort of basic calculus taught in schools. It allows you to
compute real world things like how a cable will hang between two poles.

Likewise for tensor differential analysis working in non-Euclidean
curved coordinate frames (I haven't really used that in anger for
decades now). OTOH being exposed to it broadens the mind.
--
Martin Brown
Jeroen Belleman
2024-06-10 21:52:01 UTC
Permalink
Post by john larkin
On Mon, 10 Jun 2024 17:55:47 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by Liz Tuddenham
... I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
Calculus is to arithmetic what astrology is to astronomy.
Now now, that's unjustified. Calculus is eminently useful
and perfectly rigorous.
Mathematics is a tool chest. Unfortunately, the way it's
taught, few people end up being able to use the tools.
Jeroen Belleman
How often do you use real, symbolic calculus?
Not all that often. For most functions I encounter, I
already know the solution.
Post by john larkin
Solving differential equations?
From time to time, using Laplace for the continuous domain,
and Z-transforms for discrete-time things.

Jeroen Belleman
Bill Sloman
2024-06-10 14:50:10 UTC
Permalink
Post by Jeff Layman
Post by bitrex
Post by Martin Brown
Post by john larkin
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
The general public tends to be exceptionally mathematics-averse. Even
many people with advanced degrees in fields outside the hard sciences
tend to be pretty math-averse.
Absolutely correct. I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small".
It helps if you get exposed to finite differences. In my Ph.D. work I
had to do a certain amount of numerical integration, using small but
finite steps.

To prove that the steps were small enough, I cut the step size by a
factor of three and got an integral that was the same out to five
significant digits (and the difference was probably rounding error in
the digital arithmetic).
Post by Jeff Layman
I learnt to use the formulae for differentiation
and integration and passed my exams, but my eyes clouded over then as
far as abstract mathematical concepts are concerned, and they've never
cleared! It's quite possible that I have to be able to imagine most
things to understand them, and, to me, mathematics is just not within my
imagination.
Post by bitrex
There's a modest subset of the population that's math-averse but is not
averse to trying to learn something qualitative about quantum physics or
the Riemann Hypothesis or some other mathematical aspect of the hard
sciences and enjoy the satisfaction of feeling like they know
_something_ more than they went in, even if the details aren't within
their grasp.
I'm interested in almost anything scientific, even if I can't understand
it. Perhaps it's better that way - I don't have to see the wood for the
trees!
There's no wood without trees.
Post by Jeff Layman
Post by bitrex
In contrast to the rather large subset of the population, even people
with college degrees, who are OK with not knowing the first thing about
such topics, and tend to prefer it that way.
It saves time. It probably isn't a wise choice.
--
Bill Sloman, Sydney
--
This email has been checked for viruses by Norton antivirus software.
www.norton.com
bitrex
2024-06-10 15:50:15 UTC
Permalink
Post by Jeff Layman
Post by bitrex
Post by Martin Brown
Post by john larkin
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
The general public tends to be exceptionally mathematics-averse. Even
many people with advanced degrees in fields outside the hard sciences
tend to be pretty math-averse.
Absolutely correct. I was ok with mathematics in school until we started
on calculus. I could not, and still cannot, understand concepts such as
"vanishingly small". I learnt to use the formulae for differentiation
and integration and passed my exams, but my eyes clouded over then as
far as abstract mathematical concepts are concerned, and they've never
cleared! It's quite possible that I have to be able to imagine most
things to understand them, and, to me, mathematics is just not within my
imagination.
It's not always productive to try to visualize problems. That many
mathematical objects may not be within your imagination I don't think is
any reflection on you, it's likely the same with many mathematicians.

The mathematical formalism of quantum mechanics is IMO a lot easier to
understand and feel like you've learned something from than with
classical electromagnetics or any of those wretched spinning top
problems from classical physics...much less "introductory" books on
general relativity which tend to start out like "It's therefore clear
that this bijection of a compact homeomorphism is a subset of a
Minkowski fiber bundle..."

With respect to the differential or "vanishingly small" dx in calculus
it can also be productive to, instead of trying to visualize what a
differential "actually is", look at it from the linear
algebra/functional programming perspective. Everything's a function.
f(x) is a function. x is a function. dx is a function, and the "dx"
function behaves like a linear map as described in the second half of:

<https://en.wikipedia.org/wiki/Differential_(mathematics)>
Jeroen Belleman
2024-06-10 15:10:29 UTC
Permalink
Post by bitrex
Post by Martin Brown
Post by john larkin
That's hardly usual, or a reason to call him wrong. He won the Nobel
Prize just to get free plane tickets.
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
The general public tends to be exceptionally mathematics-averse. Even
many people with advanced degrees in fields outside the hard sciences
tend to be pretty math-averse.
I'm not all that math-averse, but a formula is a shorthand notation
of some relation, and often it will take some time to parse. If it
contains unfamiliar symbols, there is little hope of making sense
of it. If someone throws a formula at me that is more than a little
involved, I tend to skip over it in the hope that the accompanying
text will give me enough context.

Formulas are often enlightening. For a long time, I was puzzled
by "forces that drop off faster than 1/r^2". How could that be?
It turns out the reason is that whatever transmits the influence
*decays*. The formula had an extra factor exp(-t/tau) in it. I'd
never heard anyone explain it that way. Only the formula made it
clear. You'd get the same kind of expression to describe the number
of soap bubbles hitting a remote target. If done right, it would
even be quantized. But that's not how it's explained. You always
hear this mystic "drop off faster than..." phrase.

[...]
Jeroen Belleman
Jeroen Belleman
2024-06-10 10:42:53 UTC
Permalink
Post by Martin Brown
Post by john larkin
On Sun, 9 Jun 2024 20:46:53 +0200, Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
Link please? It is impossible to comment without seeing his talk.
The talk is this one:

He had much the same talk to what looked like a class of university
students.

[...]
Post by Martin Brown
I'm not quite sure what he has said that annoyed JB - usually any
popular science programme for a general audience dumbs down quantum
mechanics to a point where it is completely unrecognisable to
professional physicists.
What irritates me is that QM is presented as if it's a great
mystery and that no example of an experimental setup is shown,
even schematically. That denies the listeners the opportunity
to think about it for themselves. His argument using dice is
entirely empty of any useful meaning.

Some years ago, I had a closer look at a publication of his:
"Quantum imaging with undetected photons", doi:10.1038/nature13586,
in which the observed phenomenon was described as some quantum
mechanical miracle. While the experiment was certainly not easy to
conduct, what was actually going on is trivial to understand, and
in classical terms too.

The QM clique doesn't *want* to make things understandable.

Jeroen Belleman
Jan Panteltje
2024-06-10 06:04:27 UTC
Permalink
On a sunny day (Sun, 9 Jun 2024 20:46:53 +0200) it happened Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
Agreed, so much quantum crap, almost like glowball worming sales...
Perfessors, Albert the stone counter..
This is nice and came close to the space filled with a fluid paper you gave a link to:
https://www.sciencedaily.com/releases/2024/06/240606152154.htm
it is likely not 100% correct, but a fluid of femtoscopic black holes?

In my school days I came across cases that were obviously wrong,
I declined arguing with the teacher in the days before the exams..

Entanglement
Imagine you on the beach.
You put a ball in the water, and a few meters away somebody else does the same.
Mysteriously both balls go up and down at the same moment,
'entangled'
Wave crashing on the beach.
There was an experiment recently where they had 2 detectors in the lab, meters away,
connected by a mile of fiber.
Photons were entangled...
Well , in that beach experiment you can tie a wire a mile long between the balls and they still go up and down the same time.

This is simplified, but the detection is then indeed quantified.
I like to play with PMTs etc, do those perfessors know ANYTHING about the equipment they use?
Or even DESIGNED anything ?
john larkin
2024-06-10 14:20:17 UTC
Permalink
Post by Jan Panteltje
On a sunny day (Sun, 9 Jun 2024 20:46:53 +0200) it happened Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
Agreed, so much quantum crap, almost like glowball worming sales...
Perfessors, Albert the stone counter..
https://www.sciencedaily.com/releases/2024/06/240606152154.htm
it is likely not 100% correct, but a fluid of femtoscopic black holes?
In my school days I came across cases that were obviously wrong,
I declined arguing with the teacher in the days before the exams..
Entanglement
Imagine you on the beach.
You put a ball in the water, and a few meters away somebody else does the same.
Mysteriously both balls go up and down at the same moment,
'entangled'
Wave crashing on the beach.
There was an experiment recently where they had 2 detectors in the lab, meters away,
connected by a mile of fiber.
Photons were entangled...
Well , in that beach experiment you can tie a wire a mile long between the balls and they still go up and down the same time.
This is simplified, but the detection is then indeed quantified.
I like to play with PMTs etc, do those perfessors know ANYTHING about the equipment they use?
Or even DESIGNED anything ?
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.

Nor can single-photon interferance.

Just accept and enjoy it.
Jeroen Belleman
2024-06-10 16:25:30 UTC
Permalink
Post by john larkin
Post by Jan Panteltje
On a sunny day (Sun, 9 Jun 2024 20:46:53 +0200) it happened Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
Agreed, so much quantum crap, almost like glowball worming sales...
Perfessors, Albert the stone counter..
https://www.sciencedaily.com/releases/2024/06/240606152154.htm
it is likely not 100% correct, but a fluid of femtoscopic black holes?
In my school days I came across cases that were obviously wrong,
I declined arguing with the teacher in the days before the exams..
Entanglement
Imagine you on the beach.
You put a ball in the water, and a few meters away somebody else does the same.
Mysteriously both balls go up and down at the same moment,
'entangled'
Wave crashing on the beach.
There was an experiment recently where they had 2 detectors in the lab, meters away,
connected by a mile of fiber.
Photons were entangled...
Well , in that beach experiment you can tie a wire a mile long between the balls and they still go up and down the same time.
This is simplified, but the detection is then indeed quantified.
I like to play with PMTs etc, do those perfessors know ANYTHING about the equipment they use?
Or even DESIGNED anything ?
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.

What size do you imagine a photon to be?

Jeroen Belleman
Martin Brown
2024-06-10 17:28:06 UTC
Permalink
Post by Jeroen Belleman
Post by john larkin
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.
But that world view is backed up by experiments.

Particles can behave as waves and waves can behave as particles
depending on the experiment. The particle isn't "everywhere at once"
either it is trapped in a spherical shell radius vt expanding around its
point of origin with the amplitude of the wavefunction representing the
chances of finding it at any particular position.
Post by Jeroen Belleman
What size do you imagine a photon to be?
Depends on the wavelength of the photon but to have a well defined
frequency the amplitude envelope has to be a good few wavelengths long
and to agree with causality the leading edge must be zero until
sufficient time has passed from its emission to reaching its target. I
expect that there is a canonical shape for a photon amplitude envelope
for given df/f but I don't know what it is or if it has ever been computed.

This aspect of size of a photon always seemed very awkward to me when
working at 21cm neutral hydrogen and measuring what are essentially tiny
correlations in narrowband random noise from extremely remote mostly
point sources over a large number of different antenna pairs. What is
pretty clear is that the correlations of such signals are good enough
even on planetary dimensions for VLBI to work!
--
Martin Brown
Phil Hobbs
2024-06-10 18:26:49 UTC
Permalink
Post by Martin Brown
Post by Jeroen Belleman
Post by john larkin
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.
But that world view is backed up by experiments.
Particles can behave as waves and waves can behave as particles
depending on the experiment. The particle isn't "everywhere at once"
either it is trapped in a spherical shell radius vt expanding around its
point of origin with the amplitude of the wavefunction representing the
chances of finding it at any particular position.
Post by Jeroen Belleman
What size do you imagine a photon to be?
Depends on the wavelength of the photon but to have a well defined
frequency the amplitude envelope has to be a good few wavelengths long
and to agree with causality the leading edge must be zero until
sufficient time has passed from its emission to reaching its target. I
expect that there is a canonical shape for a photon amplitude envelope
for given df/f but I don't know what it is or if it has ever been computed.
This aspect of size of a photon always seemed very awkward to me when
working at 21cm neutral hydrogen and measuring what are essentially tiny
correlations in narrowband random noise from extremely remote mostly
point sources over a large number of different antenna pairs. What is
pretty clear is that the correlations of such signals are good enough
even on planetary dimensions for VLBI to work!
Sticking with the semiclassical picture of photodetection is good, because
it avoids almost all of the blunders made by the photons-as-billiard-balls
folk, but it doesn’t get you out of the mystery.

The really mysterious thing about photodetection is that a given photon (*)

incident on a large lossless detector gives rise to exactly one detection
event, with probability spatialy and temporally weighted by E**2.

Doesn’t seem so bad yet, but consider this:
If the detector is large compared with the pulse width/c, distant points on
the detector are separated by a spacelike interval.

That means that so when point A detects it, there is no way for the
information reach point B before the end of the pulse, when E drops to
zero, and yet experimentally point B doesn’t detect it.

(*) a quantized excitation of a harmonic oscillator mode of the EM field in
a given set of boundary conditions)

Cheers

Phil Hobbs
--
Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC /
Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics
Phil Hobbs
2024-06-10 18:40:51 UTC
Permalink
Post by Phil Hobbs
Post by Martin Brown
Post by Jeroen Belleman
Post by john larkin
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.
But that world view is backed up by experiments.
Particles can behave as waves and waves can behave as particles
depending on the experiment. The particle isn't "everywhere at once"
either it is trapped in a spherical shell radius vt expanding around its
point of origin with the amplitude of the wavefunction representing the
chances of finding it at any particular position.
Post by Jeroen Belleman
What size do you imagine a photon to be?
Depends on the wavelength of the photon but to have a well defined
frequency the amplitude envelope has to be a good few wavelengths long
and to agree with causality the leading edge must be zero until
sufficient time has passed from its emission to reaching its target. I
expect that there is a canonical shape for a photon amplitude envelope
for given df/f but I don't know what it is or if it has ever been computed.
This aspect of size of a photon always seemed very awkward to me when
working at 21cm neutral hydrogen and measuring what are essentially tiny
correlations in narrowband random noise from extremely remote mostly
point sources over a large number of different antenna pairs. What is
pretty clear is that the correlations of such signals are good enough
even on planetary dimensions for VLBI to work!
(Edited for clarity—posting from my phone)
Post by Phil Hobbs
Sticking with the semiclassical picture of photodetection is good, because
it avoids almost all of the blunders made by the photons-as-billiard-balls
folk, but it doesn’t get you out of the mystery.
The really mysterious thing about photodetection is that a given photon (*)
incident on a large lossless detector gives rise to exactly one detection
event, with probability spatialy and temporally weighted by E**2.
If the detector is large compared with the pulse width/c, distant points on
the detector are separated by a spacelike interval.
That means that when point A detects it, there is no way for that
information to reach point B before the end of the pulse, when E drops to
zero, and yet experimentally point B doesn’t detect it.
(*) a quantized excitation of a harmonic oscillator mode of the EM field in
a given set of boundary conditions)
Cheers
Phil Hobbs
--
Dr Philip C D Hobbs Principal Consultant ElectroOptical Innovations LLC /
Hobbs ElectroOptics Optics, Electro-optics, Photonics, Analog Electronics
Jeroen Belleman
2024-06-10 21:15:51 UTC
Permalink
On 6/10/24 20:26, Phil Hobbs wrote:

[Snip...]
Post by Phil Hobbs
Sticking with the semiclassical picture of photodetection is good, because
it avoids almost all of the blunders made by the photons-as-billiard-balls
folk, but it doesn’t get you out of the mystery.
The really mysterious thing about photodetection is that a given photon (*)
incident on a large lossless detector gives rise to exactly one detection
event, with probability spatialy and temporally weighted by E**2.
If the detector is large compared with the pulse width/c, distant points on
the detector are separated by a spacelike interval.
That means that so when point A detects it, there is no way for the
information reach point B before the end of the pulse, when E drops to
zero, and yet experimentally point B doesn’t detect it.
(*) a quantized excitation of a harmonic oscillator mode of the EM field in
a given set of boundary conditions)
Cheers
Phil Hobbs
We don't have single-photon-on-demand sources, nor perfect detectors.
Both sources and detectors are probabilistic. I'd like to see how
this argument fares using energy resolving detectors like TESs.

I do not expect the probability of a detection event in one spot to
be affected instantly by a detection event somewhere else. The
collapse of the wave function is an attempt to apply statistical
reasoning to a single event.

Jeroen Belleman
john larkin
2024-06-10 21:24:39 UTC
Permalink
On Mon, 10 Jun 2024 23:15:51 +0200, Jeroen Belleman
Post by Jeroen Belleman
[Snip...]
Post by Phil Hobbs
Sticking with the semiclassical picture of photodetection is good, because
it avoids almost all of the blunders made by the photons-as-billiard-balls
folk, but it doesn’t get you out of the mystery.
The really mysterious thing about photodetection is that a given photon (*)
incident on a large lossless detector gives rise to exactly one detection
event, with probability spatialy and temporally weighted by E**2.
If the detector is large compared with the pulse width/c, distant points on
the detector are separated by a spacelike interval.
That means that so when point A detects it, there is no way for the
information reach point B before the end of the pulse, when E drops to
zero, and yet experimentally point B doesn’t detect it.
(*) a quantized excitation of a harmonic oscillator mode of the EM field in
a given set of boundary conditions)
Cheers
Phil Hobbs
We don't have single-photon-on-demand sources, nor perfect detectors.
Both sources and detectors are probabilistic. I'd like to see how
this argument fares using energy resolving detectors like TESs.
I do not expect the probability of a detection event in one spot to
be affected instantly by a detection event somewhere else. The
collapse of the wave function is an attempt to apply statistical
reasoning to a single event.
Jeroen Belleman
Higher energy photons, like gamma rays, can be detected with 100%
probability. They pack a lot of energy.
Martin Brown
2024-06-11 11:06:05 UTC
Permalink
Post by john larkin
On Mon, 10 Jun 2024 23:15:51 +0200, Jeroen Belleman
Post by Jeroen Belleman
I do not expect the probability of a detection event in one spot to
be affected instantly by a detection event somewhere else. The
collapse of the wave function is an attempt to apply statistical
reasoning to a single event.
Jeroen Belleman
Higher energy photons, like gamma rays, can be detected with 100%
probability. They pack a lot of energy.
No they can't. It isn't called penetrating radiation for nothing. Most
of it goes straight through all but the densest of targets. The odd one
gets lucky and hits something and then we see scintillation.

Some of the solid state NaI(Tl) detectors are getting pretty close to
100% for some energy ranges but the majority are around 50% at best. Big
step up from the old GM tube counters 0.1-1% though.

Likewise higher energy X-rays goes straight through most matter like it
wasn't there. You are always playing a numbers game of detections being
a fraction of the flux passing through (unless the target is optically
dense) which Earth's atmosphere is for most ionising radiation.

Ultra high energy cosmic ray particles generate an airshower of less
energetic secondary particles most of which wouldn't reach the ground
except for the effects of relativity. Some of them have been estimated
from the total yield to be carrying as much energy as a cricket ball.
Not bad for a single Fe56 nucleus!

Ground based detectors can measure the secondaries, timings and spatial
distribution and make a reasonable guess about the energy it had.
--
Martin Brown
Jeroen Belleman
2024-06-11 20:06:10 UTC
Permalink
Post by john larkin
On Mon, 10 Jun 2024 23:15:51 +0200, Jeroen Belleman
Post by Jeroen Belleman
[Snip...]
Post by Phil Hobbs
Sticking with the semiclassical picture of photodetection is good, because
it avoids almost all of the blunders made by the photons-as-billiard-balls
folk, but it doesn’t get you out of the mystery.
The really mysterious thing about photodetection is that a given photon (*)
incident on a large lossless detector gives rise to exactly one detection
event, with probability spatialy and temporally weighted by E**2.
If the detector is large compared with the pulse width/c, distant points on
the detector are separated by a spacelike interval.
That means that so when point A detects it, there is no way for the
information reach point B before the end of the pulse, when E drops to
zero, and yet experimentally point B doesn’t detect it.
(*) a quantized excitation of a harmonic oscillator mode of the EM field in
a given set of boundary conditions)
Cheers
Phil Hobbs
We don't have single-photon-on-demand sources, nor perfect detectors.
Both sources and detectors are probabilistic. I'd like to see how
this argument fares using energy resolving detectors like TESs.
I do not expect the probability of a detection event in one spot to
be affected instantly by a detection event somewhere else. The
collapse of the wave function is an attempt to apply statistical
reasoning to a single event.
Jeroen Belleman
Higher energy photons, like gamma rays, can be detected with 100%
probability. They pack a lot of energy.
Yes, but you'd need to use quite dense stuff to have a good
chance of intercepting it. Lead tungstate is the thing these
days.

Jeroen Belleman
john larkin
2024-06-11 20:27:04 UTC
Permalink
On Tue, 11 Jun 2024 22:06:10 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by john larkin
On Mon, 10 Jun 2024 23:15:51 +0200, Jeroen Belleman
Post by Jeroen Belleman
[Snip...]
Post by Phil Hobbs
Sticking with the semiclassical picture of photodetection is good, because
it avoids almost all of the blunders made by the photons-as-billiard-balls
folk, but it doesn’t get you out of the mystery.
The really mysterious thing about photodetection is that a given photon (*)
incident on a large lossless detector gives rise to exactly one detection
event, with probability spatialy and temporally weighted by E**2.
If the detector is large compared with the pulse width/c, distant points on
the detector are separated by a spacelike interval.
That means that so when point A detects it, there is no way for the
information reach point B before the end of the pulse, when E drops to
zero, and yet experimentally point B doesn’t detect it.
(*) a quantized excitation of a harmonic oscillator mode of the EM field in
a given set of boundary conditions)
Cheers
Phil Hobbs
We don't have single-photon-on-demand sources, nor perfect detectors.
Both sources and detectors are probabilistic. I'd like to see how
this argument fares using energy resolving detectors like TESs.
I do not expect the probability of a detection event in one spot to
be affected instantly by a detection event somewhere else. The
collapse of the wave function is an attempt to apply statistical
reasoning to a single event.
Jeroen Belleman
Higher energy photons, like gamma rays, can be detected with 100%
probability. They pack a lot of energy.
Yes, but you'd need to use quite dense stuff to have a good
chance of intercepting it. Lead tungstate is the thing these
days.
Jeroen Belleman
I suspect that a tight spectral resolution (and some gamma lines are a
few per cent wide) implies high detection efficiency.

Visible light is just too wimpy to get clear quantum detection.

john larkin
2024-06-10 18:59:44 UTC
Permalink
On Mon, 10 Jun 2024 18:25:30 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by john larkin
Post by Jan Panteltje
On a sunny day (Sun, 9 Jun 2024 20:46:53 +0200) it happened Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
Agreed, so much quantum crap, almost like glowball worming sales...
Perfessors, Albert the stone counter..
https://www.sciencedaily.com/releases/2024/06/240606152154.htm
it is likely not 100% correct, but a fluid of femtoscopic black holes?
In my school days I came across cases that were obviously wrong,
I declined arguing with the teacher in the days before the exams..
Entanglement
Imagine you on the beach.
You put a ball in the water, and a few meters away somebody else does the same.
Mysteriously both balls go up and down at the same moment,
'entangled'
Wave crashing on the beach.
There was an experiment recently where they had 2 detectors in the lab, meters away,
connected by a mile of fiber.
Photons were entangled...
Well , in that beach experiment you can tie a wire a mile long between the balls and they still go up and down the same time.
This is simplified, but the detection is then indeed quantified.
I like to play with PMTs etc, do those perfessors know ANYTHING about the equipment they use?
Or even DESIGNED anything ?
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.
What size do you imagine a photon to be?
It's unlimited. You can have an interferometer with different arm
lengths and still get single-photon interferance.

I noticed that on a lithium niobate Mach-Zender e/o modulator. The
interfering path lengths are different by thousands of wavelengths.
Jeroen Belleman
2024-06-10 20:31:08 UTC
Permalink
Post by john larkin
On Mon, 10 Jun 2024 18:25:30 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by john larkin
Post by Jan Panteltje
On a sunny day (Sun, 9 Jun 2024 20:46:53 +0200) it happened Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
Agreed, so much quantum crap, almost like glowball worming sales...
Perfessors, Albert the stone counter..
https://www.sciencedaily.com/releases/2024/06/240606152154.htm
it is likely not 100% correct, but a fluid of femtoscopic black holes?
In my school days I came across cases that were obviously wrong,
I declined arguing with the teacher in the days before the exams..
Entanglement
Imagine you on the beach.
You put a ball in the water, and a few meters away somebody else does the same.
Mysteriously both balls go up and down at the same moment,
'entangled'
Wave crashing on the beach.
There was an experiment recently where they had 2 detectors in the lab, meters away,
connected by a mile of fiber.
Photons were entangled...
Well , in that beach experiment you can tie a wire a mile long between the balls and they still go up and down the same time.
This is simplified, but the detection is then indeed quantified.
I like to play with PMTs etc, do those perfessors know ANYTHING about the equipment they use?
Or even DESIGNED anything ?
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.
What size do you imagine a photon to be?
It's unlimited. You can have an interferometer with different arm
lengths and still get single-photon interferance.
I noticed that on a lithium niobate Mach-Zender e/o modulator. The
interfering path lengths are different by thousands of wavelengths.
Exactly! The path length difference is limited only by the coherence
length of the light source. This is all quite natural when thinking
in terms of waves. When you think of it in terms of photons, it stops
making any sense.

Jeroen Belleman
john larkin
2024-06-10 21:17:41 UTC
Permalink
On Mon, 10 Jun 2024 22:31:08 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by john larkin
On Mon, 10 Jun 2024 18:25:30 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by john larkin
Post by Jan Panteltje
On a sunny day (Sun, 9 Jun 2024 20:46:53 +0200) it happened Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
Agreed, so much quantum crap, almost like glowball worming sales...
Perfessors, Albert the stone counter..
https://www.sciencedaily.com/releases/2024/06/240606152154.htm
it is likely not 100% correct, but a fluid of femtoscopic black holes?
In my school days I came across cases that were obviously wrong,
I declined arguing with the teacher in the days before the exams..
Entanglement
Imagine you on the beach.
You put a ball in the water, and a few meters away somebody else does the same.
Mysteriously both balls go up and down at the same moment,
'entangled'
Wave crashing on the beach.
There was an experiment recently where they had 2 detectors in the lab, meters away,
connected by a mile of fiber.
Photons were entangled...
Well , in that beach experiment you can tie a wire a mile long between the balls and they still go up and down the same time.
This is simplified, but the detection is then indeed quantified.
I like to play with PMTs etc, do those perfessors know ANYTHING about the equipment they use?
Or even DESIGNED anything ?
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.
What size do you imagine a photon to be?
It's unlimited. You can have an interferometer with different arm
lengths and still get single-photon interferance.
I noticed that on a lithium niobate Mach-Zender e/o modulator. The
interfering path lengths are different by thousands of wavelengths.
Exactly! The path length difference is limited only by the coherence
length of the light source. This is all quite natural when thinking
in terms of waves. When you think of it in terms of photons, it stops
making any sense.
Jeroen Belleman
A single photon has an infinite coherence length.

What's weird is that I can pulse a superfast laser and hit a detector
with picosecond time delay jitter, even though another experiment
shows that each photon is very long.

It's apparently easy for you to accept that light is made of waves
until it's detected, at which time it turns into particles.

That's the part that's magical to me.
Jeroen Belleman
2024-06-10 21:58:54 UTC
Permalink
Post by john larkin
On Mon, 10 Jun 2024 22:31:08 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by john larkin
On Mon, 10 Jun 2024 18:25:30 +0200, Jeroen Belleman
Post by Jeroen Belleman
Post by john larkin
Post by Jan Panteltje
On a sunny day (Sun, 9 Jun 2024 20:46:53 +0200) it happened Jeroen Belleman
Post by Jeroen Belleman
I just watched a talk by Anton Zeilinger, professor of physics
at the university of Vienna, and 2022 Nobel laureate, about
quantum effects and entanglement.
I feel a rant bubbling up!
The guy is a mystic, a fraud! He pretended to demonstrate that
light consists of particles by showing a little box that starts
clicking, like a Geiger counter, when exposed to light. Even if
the little box really did detect light, that means nothing! Light
*detection* is quantized, yes, but that does not imply that light
itself is so too.
He attempted to convince the public that entanglement means that
the results of measurements made at two remote places come out
identically, and without any time delay. That's just not true,
but he didn't even give a hint of how this really works. He did
not mention that you have to make *correlated* measurements to
detect entanglement. For that, you need to communicate *what*
measurement is to be made at each location, and that implies
that you either prescribe the exact measurement in advance or
select a subset of the results after the fact. Either way, this
skews the data.
He's in it for the money and the fame. Grrr. And he's one of
many, too.
Jeroen Belleman
Agreed, so much quantum crap, almost like glowball worming sales...
Perfessors, Albert the stone counter..
https://www.sciencedaily.com/releases/2024/06/240606152154.htm
it is likely not 100% correct, but a fluid of femtoscopic black holes?
In my school days I came across cases that were obviously wrong,
I declined arguing with the teacher in the days before the exams..
Entanglement
Imagine you on the beach.
You put a ball in the water, and a few meters away somebody else does the same.
Mysteriously both balls go up and down at the same moment,
'entangled'
Wave crashing on the beach.
There was an experiment recently where they had 2 detectors in the lab, meters away,
connected by a mile of fiber.
Photons were entangled...
Well , in that beach experiment you can tie a wire a mile long between the balls and they still go up and down the same time.
This is simplified, but the detection is then indeed quantified.
I like to play with PMTs etc, do those perfessors know ANYTHING about the equipment they use?
Or even DESIGNED anything ?
But photon entanglement can't be explained, or even thought about, in
classic-physics terms.
Nor can single-photon interferance.
Just accept and enjoy it.
That's false! Entanglement and interference can easily be understood
in terms of waves and quantized detectors. It's the QM view, with its
imagined photon particle flying everywhere at once that is confusing.
What size do you imagine a photon to be?
It's unlimited. You can have an interferometer with different arm
lengths and still get single-photon interferance.
I noticed that on a lithium niobate Mach-Zender e/o modulator. The
interfering path lengths are different by thousands of wavelengths.
Exactly! The path length difference is limited only by the coherence
length of the light source. This is all quite natural when thinking
in terms of waves. When you think of it in terms of photons, it stops
making any sense.
Jeroen Belleman
A single photon has an infinite coherence length.
What's weird is that I can pulse a superfast laser and hit a detector
with picosecond time delay jitter, even though another experiment
shows that each photon is very long.
It's apparently easy for you to accept that light is made of waves
until it's detected, at which time it turns into particles.
That's the part that's magical to me.
I wouldn't say it like that. I'd say that the incident wave causes
a detection event. I'd never say that *light* is a particle. Where
matter and waves interact, quantization occurs.

Jeroen Belleman
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