The Tayur Musings on Physics😏

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I didn’t realize that I was already (for decades) doing what Feynman had suggested: to read haphazardly whatever I liked about physics.☺️

I found out something else today.

The Feynman Lectures on Physics was made possible by funding from, guess who, Ford Foundation.

I hold the Ford Distinguished Research Chair funded by the same Ford Foundation!😳 I found particularly appealing his motivation:

It is perfectly clear that students who will major in physics can wait until the third year for quantum mechanics. On the other hand the argument was made that many of the students in our course study physics as a background for their primary interest in other fields, and the usual way of dealing with Quantum Mechanics, makes that subject almost unavailable for the great majority of students because they have to take so long to learn it.  Yet in its real applications, especially in its more complex applications, such as in electrical engineering and chemistry, the full machinery of the differential equation approach is not actually used.  So, I tried to describe the principles of quantum mechanics in a way, which wouldn’t require that one first to know the mathematics of partial differential equations. Even for a physicist, I think this is an interesting thing to try: to present quantum mechanics in this reverse fashion.

Is The Tayur Musings on Physics in MyAmpleLife just a vanity project? Not entirely. It is a mechanism to distill important concepts in physics at a level that is understandable by many, especially a STEM trained person. Who is it for really? It certainly is for me personally, but it might also serve others like me, but who do not have the time or patience to read dozens of books, ranging from technical textbooks to non-mathematical expositions, but would like, nevertheless, to not only understand important developments, both foundational as well as applications, in English, but also see some of the mathematics that form the basis of the (English) exposition.

What do I mean by foundational? Say, derivation of Planck’s formula (see above); Fermi-Dirac and Bose-Einstein statistics; Heisenberg Uncertainty Principle; Special Relativity; Dirac equation; Symmetry, Invariance and Conservation;  Quantum Fields; quantum theory of light; anti-bunching; spontaneous symmetry breaking; General Relativity; Black Holes; Expanding universe;  Neutrinos; Quantum thermodynamics; quantum information science. What do I mean by applications? Chandrasekhar Limit; Lasers, Blu-ray, scanning tunneling microscope; Ising; quantum random number generator; transistors; superconductivity; atomic clocks; photolithography; cloaking; fiber optics; meta-materials; MRI; CCD; holograms; 3-D movies; ghost imaging; quantum teleportation; quantum random number generator; quantum digital payment; Grover search; quantum computing; magnetism; photoelectric effect; Squeezed Light and Quantum Sensing. And so on.

What is squeezed light? It is a pair of photons that behave as a single unit. (Recall, in Superconductivity, how a pair of electrons work as an unit, become a boson, although individually there are fermions?)  If you draw the typical sinusoidal wave picture, a typical stream of photons, even from a laser, called a coherent source, different from a thermal source, it will have some fundamental non-zero quantum noise, which means that there is uncertainty in its phase and its amplitude. The uncertainty is uniform in the entire cycle. In contrast, with squeezed light, you have uncertainty that depends on where you are in the sinusoidal curve. Specifically, you can  less uncertainty near zero phase and far greater uncertainty in the amplitude (a quarter cycle later); one can view phase and photon number as a complementary conjugate quantum mechanical pair. (Following Heisenberg uncertainty principle, if you want more certainty in the phase, you will have to live with greater uncertainty in the amplitude.) This allows one to have greater precision than previously thought possible (beyond that was considered as a fundamental limit that cannot be bettered!), and this is useful in measuring gravitational waves in LIGO, for example.

I have derived photon statistics for coherent (lasers, Poisson distribution) and thermal light (Super-Poisson, Bose-Einstein distribution, Blackbody radiation, Planck stuff) above. There is also something called sub-Poisson light, that is based on anti-bunching, and is a purely quantum mechanical phenomenon! If you wondered who developed this quantum optics stuff:

The Nobel Prize in Physics 2005 was divided, one half awarded to Roy J. Glauberfor his contribution to the quantum theory of optical coherence”, the other half jointly to John L. Hall and Theodor W. Hänsch “for their contributions to the development of laser-based precision spectroscopy, including the optical frequency comb technique”

John Hall is a CMU alum (1961 PhD, Physics). Why am I so interested? I have fallen in love with Quantum Light. Also:

The Second Quantum Revolution is about Quantum Dots (for Quantum Computing), Single Photon sources (for Quantum Cryptography/Communication) and Squeezed Light (for Quantum Sensing).

I will be giving a Public Lecture on The Second Quantum Revolution on August 24th, as part of TIE Pittsburgh Speaker Series.

What about Movies. and Streaming? No Hard Feelings. Boring. Dial of Destiny. Silly, disappointing. Class of 09. Predictable. Drops of God. Stereotypes galore (French, Japanese and Italian!). DI Ray. Missed opportunity. Jack Ryan (Season 4). Four episodes in, watchable.

Martinis? I decided to try a new concoction – Pepper Vodka, Muddled Lime, Sparkling Water – Shaken (gently!), not Stirred. Meh.

Looking forward to Mission Impossible: Dead Reckoning (Part 1) and, of course, Oppenheimer.

Earlier I received this email from Arko Dasgupta (see La Femme Nikki?) reacting to my last post (Le Taj):

Jean Renoir also made this remarkable film called The River (1951), which was shot in Calcutta. Satyajit Ray met him and also Subrata Mitra, who was assisting Renoir, and struck up a friendship with both of them. Mitra later went on to become Ray’s favoured cinematographer. Tarantino was apparently inspired by Kamal Hassan’s Aalavandhan/Abhay as he was filming Kill BillPulp Fiction of course is a class apart.

Cool stuff!



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