What book are you reading right now?

Bit of a shaggy dog tale

Paradox, by Jim Al-Khalili.

Takes you quietly past Monty Hall and Achilles into relativity and GPS. Almost lets you think you actually understand some of these things

Written in 1972, this examination of the great man's films is readable and clearly from the pen of an admirer. It come from an odd time in film criticism, after auteur theory but before the diseased waffle of structuralism, semiotics etc. So far it's pretty good, quite a few interesting insights that make one want to see the films again.

He is a bit like watching an empty badger sett.

That's not good because when you think you understand Relativity and/or Quantum Mechanics then you almost certainly don't.

Yep ! That's exactly what I mean !

Monty Hall and Achilles I am confident about. Relativity ? ok it works in our GPS systems so I accept that its a very, very useful model with which to work, but some most of the concepts are difficult to grasp and impossible to understand. We just aren't aware of them in everyday life.

Quantum Mechanics is in the next chapter...............even more unbelievable, even after reading our Brian's little book.

 The '"If you think you understand quantum mechanics, you don't understand quantum mechanics." statement is often quoted by people that seek to make the erroneous point that quantum physics is not understood. The mathematics and equations are very well understood. This remark was a throw away comment in a lecture give by Richard Feynman at Cornell University in 1964 to titillate his audience and it was meant as a joke - it has been regularly misused ever since. What quantum mechanics means is a different story and this subject is hotly debated although not very well by either Brian Cox or the very confused Al-Khalili. 

Brian's little book is "The Quantum Universe". I mentioned it a few months back in this thread.

He might not be very good at debating, but he does have an engaging way of explaining things.

Quantum Mechanics is NOT very well understood.  Take for instance 'entangled particles', can you tell me what the mechanism is that causes the entanglement.  Remember that this will work across vast distances and is immediate - NO light speed lag!

As Richard Feynman said we cannot understand QM in terms that relate to our everyday existence.  Exactly how does a single photon (or an electron etc) cause interference patterns on a target screen, yup we an understand it when two particles passing through two different slits do it - but how does it work with one particle and why does this behaviour disappear when you measure which slit the particle goes through.

Can you really understand this

Our current understanding is that these very small particles don't really exist until we measure where they are - ie Schrödinger's Cat.  The probability wave collapses we are told.  But the collapsing probability wave is not something that comes out of the maths, this is something shoe-horned in to the theory.

Funny enough it is not a throw away statement, it is meant to help!  It is meant to clear the mind of a student of QM.  To describe it as erroneous and that it is misused is odd but if you can explain QM then maybe you are right.  Feynman was a great scientist (of course) but he was also a great teacher and he couldn't explain it!

Yes much of QM can be understood and certainly it's contribution to our understanding of Chemistry is huge.  Before QM we did not know why Spectroscopy worked and so we did not know what caused colour. We did not know why chemical bonds formed etc etc.  Spectroscopy btw, told us that the Universe is expanding amongst other things, so quite an important subject.

Special and General Relativity are much easier to understand.  Special talks about bodies at constant velocity NO acceleration and from this came the whole thing about time dilation.  It is this behaviour of course, that requires we take it into account in GPS!  General is when we are talking about bodies that are accelerating and Einstein brilliantly likened gravity to the force we feel when accelerating.  Thus GR explains what gravity is!  A major, major achievement!

btw I agree with what you say about Jim Al-Khalili, well his programs anyway.  In the last one I watched he tried to explain the work of the great N. Irish scientist John Bell and failed miserably.  My missus said that it made no sense and asked me to explain it - but it took a couple of hours and she is very bright (an Economist by training).

I quote Bell's law, one of the most stunning laws in science and it would have saved Schrödinger's Cat from any suffering if Erwin had known it:

No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics.

He does have charisma!

He does have charisma!

...and an LP12 now.

Bill, 

I said ' The mathematics and equations are very well understood'. 

Well maths & equations always are but they are not always the whole picture.  If you look at the work of Max Planck and his first uncovering of the Quantum World you will see that the maths may be understood but they don't provide any understanding.  Planck could fit the Black Body emission spectra to his equations if and only if the energy of the oscillating atoms was quantised.  Apparently Planck assumed that this strange thing, which totally disagreed with classical theory, would be "straightened" out at a later date.  Of course it wasn't and his equations do not tell us why energy is quantised.  Nor do the maths now!

The reason that a new theory (String Theory) was required was because the Maths at the time 'worked' but only if the particles it described were 'point-like', that is they had zero size.  There have been at least 5 different mathematical models put forward and although the maths is internally consistent there has been no real experimental backing.

Feynman's little statement that you took exception to was not saying that if you understood the maths then you might be in trouble.  He meant real understanding.  It would be nice to understand The Uncertainty Principle, or entanglement or even why micro world is quantised.  But we don't and believing that we do imho gets in the way!

'you will see that the maths may be understood but they don't provide any understanding'.

Ain't that the truth. I agree.

'The reason that a new theory (String Theory) was required was because the Maths at the time 'worked' but only if the particles it described were 'point-like', that is they had zero size. There have been at least 5 different mathematical models put forward and although the maths is internally consistent there has been no real experimental backing'.

I agree with you on string theory.

'Feynman's little statement that you took exception to was not saying that if you understood the maths then you might be in trouble. He meant real understanding'.

Feynman was a 'shut up and calculate' physicist. His remark is a disservice to science and metaphysics in my view. it can lead people to be dismissive of anything that smacks of the quantum and that understanding is not possible (then, now or in the future). Things have moved on since Feynman's day. There is a lack of agreement but that does not mean that no one understands quantum physics. Many scientific theories that are accepted today were thought outrageous when they were first published. Similarly it may well be that the growing number of physicists out on the fringes may well, one day, be known to have been right and that people like Cox will be seen as dinosaurs. 

That I totally disagree with.  I feel that you do not understand Feynam's remark, if you describe it as a disservice to science, it is a piece of Zen.  Furthermore, to say that it will lead to people being dismissive of QM in my experience is 180 deg wrong.  Not quite sure where metaphysics belongs in this discussion - nowhere in my view.

I got my degree in Chemistry in 1972 and my PhD in Biophysics in 75.  I then lectured in a couple of Universities for 11 years before going into commercial programming.  My experience with students was that they were totally beguiled by the 'unknowingness'  of QM, not put off in the least.  I consider myself a mathematician and while an academic I was on that wave of mathematicians who followed the theory boys and worked out the maths.  Those were heady days when I was being paid (not very much mind you) to do something that I would do free!  I also loved (unlike many in depts. I worked in) the lecturing aspect of the job.

Not sure what a 'shut up and calculate' physicist is but the fact that Feynman was also a very good theoretician and experimenter then I find that a bit insulting to the man.  I never met him or went to any of his lectures but I have a number of his lectures on video and they are superb.  He was funnier than the majority of US or UK comedians and yet he made you think in different ways about stuff you had fixed firmly in your mind.

A fun, well-illustrated examination of 80s music. Much of it was utter rubbish, of course, but there are a few classics (Blue Monday, Love Will Tear Us Apart especially) and decent acts: New Order, Joy Division, ABC, Devo, Numan, Soft Cell, Bunnymen, Smiths OMD...

Pedantic point: The Normal's Warm Leatherette is actually a 1970s record - it came out in 1978

For the third time.

First read of Joseph Kanon who is supposed to me a modern day Graham Green.

Just started it today:

and also this one

as I like a good historical piece of fiction however I am struggling with one of Harry's novels for the first time, no real flow to it.

That's what expects me:

"It is 1946, and a stunned Europe is beginning its slow recovery from the ravages of World War II. Adam Miller has come to Venice to visit his widowed mother and try to forget the horrors he has witnessed as a U.S. Army war crimes investigator in Germany. Nothing has changed in Venice-not the beautiful palazzi, not the violins at Florian's, not the shifting water that makes the city, untouched by bombs, still seem a dream.

But when Adam falls in love with Claudia, a Jewish woman scarred by her devastating experiences during the war, he is forced to confront another Venice, a city still at war with itself, haunted by atrocities it would rather forget. Everyone, he discovers, has been compromised by the Occupation-the international set drinking at Harry's, the police who kept order for the Germans, and most of all Gianni Maglione, the suave and enigmatic Venetian who happens to be his mother's new suitor. And when, finally, the troubled past erupts in violent murder, Adam finds himself at the center of a web of deception, intrigue, and unexpected moral dilemmas. When is murder acceptable? What are the limits of guilt? How much is someone willing to pay for a perfect alibi?

Using the piazzas and canals of Venice as an enthralling but sinister backdrop, Joseph Kanon has again written a gripping historical thriller. Alibi is at once a murder mystery, a love story, and a superbly crafted novel about the nature of moral responsibility."

A hardback bargain (£4) from the Oxfam bookshop. There is a Naim product in there, an olive NAP250, as well as an LP12 and classic designs from [designers] Dieter Rams, Sapper & Zenuso, Jakob Jensen, Dan D'Agostino, Ron Arad, Jonathan Ive, etc; and firms sugh as Braun, B&O, Boothroyd & Stuart, Quad, Nakamichi, Apple, Day- Sequerra, Sony, Marantz, Oracle, Meridian etc

What's striking is just how beautiful good industrial design - as practiced by the Germans, Scandis, Italians, Japanese and (yes!) the British can be; and how unforgiveably ugly American muscle amps (Krell, Levinson) are.

Rudyard kipling, Kim, new german translation, have read it as a child, but was too young to unterstand.