Book 21 for my 2025 goal of 30 books for the year! As is now default for me, my link to the book is through my bookshop dot org affiliate account.
Some books look intriguing to me when I first get them, but end up sitting on my shelf for ages before I finally get around to reading them. This is the case with The Further Adventures of Sherlock Holmes: The White Worm, by Sam Siciliano, first published in 2016.
This is one of a series of pastiches published by Penguin/Random House by a variety of authors, usually mashing up Holmes with some other classic literary story of the era, often of a supernatural form. In this case, Siciliano has placed Holmes into Bram Stoker’s infamous 1911 novel, The Lair of the White Worm.
This was presumably an interesting challenge. As I’ve blogged about before, The Lair of the White Worm was Stoker’s last novel, written when he was dealing with severe health challenges and possibly cognitive decline. The result is that the novel is extremely disjointed, incoherent, and difficult to read. There are, however, flashes of brilliance in its telling that show what might have been if Stoker had been in better health.
My training and background as a physicist is largely in the field of so-called classical optics: the study of the wave properties of light. Lately, however, I’ve been planning more investigations into quantum optics — the study of the quantum particle properties of light — which has recently culminated in my first published paper in the field.
One topic I’ve been reviewing in quantum optics is the concept of a “quantum eraser.” The idea arises from the general observation that wave interference is directly connected with a lack of knowledge about the evolution of a quantum particle. The classic example of this is Young’s interference experiment, illustrated below.
A source of light is collimated by a small hole in one screen, and then the light simultaneously illuminates two pinholes in a second screen. Light coming from those two holes propagate to an observation screen, where the waves from the two pinholes interfere with each other and produce bright and dark fringes that look something like this:
This argument stretches down to the single photon level. In that case, if we send a single photon through Young’s experiment, the probability of seeing the photon arrive at a point on the observation screen is proportional to the interference pattern. That is: the photon is more likely to arrive at some points rather than others due to the wave interference properties of the photon. If we tabulate the positions of a lot of photons over time, we find that the classical wave interference pattern emerges:
Here is where the idea of “information,” loosely defined, comes into play. The interference pattern for a single photon comes from the recognition that the photon wavefunction passes through both pinholes simultaneously — that is, we as experimental observers have no idea which pinhole the photon has gone through, so it has in a sense gone through both. But if we somehow set up an apparatus that can measure which pinhole the photon has gone through, we will find that the interference pattern disappears completely. Apparently, our knowledge of the path of the photon destroys the interference pattern or, conversely, our ignorance of the path of the photon allows the interference pattern to form.
The idea of a quantum eraser, first proposed by Marlan O. Scully and Kai Drühl in 19821, grows from this. Let us imagine we perform an experiment like Young’s experiment where we measure “which path” information — if nothing else is done, we expect that the interference fringes will not be present on the observation screen. Now suppose that we can somehow “destroy” this information after the photons have passed through the pinholes but before we actually measure the position of the photon on the observation screen. Because the information is no longer present, we expect to see the interference fringes manifest on the screen again! By “erasing” the information, we have caused the wave behavior to appear again. This is the basic concept of a quantum eraser.
However, this is another weird twist to all of this. It is furthermore possible in many cases to choose whether or not to destroy the “which path” information not only after the photon has passed through the two pinhole screen but even after the photon is measured at the observation screen! In this case, the phenomenon is referred to as a “delayed choice quantum eraser.” This bizarre result has often been describe as information “traveling backward in time,” as it superficially seems like the photon must revise its behavior in the past in order to give a consistent result — conforming to the presence or absence of interference — in the present. As we will see, however, this “time travel” interpretation of the is simply wrong, though the explanation of what is really going on is just as fascinating and subtle.
We’ll tackle the quantum eraser explanation in two parts, both of which will be based on Young’s interference experiment. In the first part, we will describe the basic principles using what I will call a trivial eraser, which doesn’t explicitly need quantum physics to explain it. Then we will dive into a full quantum eraser. Settle in for a somewhat lengthy post! It is also one of the most complicated things I’ve ever tried to explain in a blog post, so be patient with me!
Book 20 for my 2025 goal of 30 books for the year! As is now default for me, my link to the book is through my bookshop dot org affiliate account.
I’ve been gearing up lately to plan my next popular science book — if I ever write it — and have been doing some relevant background reading. One thing I wanted to learn more about is the story of the incredible mathematician Emmy Noether (1882-1935), who revolutionized mathematics and physics during the course of her career, even though her accomplishments remained relatively obscure after her death up until the past couple of decades, when historians and science writers worked to introduce her to both the scientific community and the general public.
Remarkably, there was not a detailed history of her life published until late last year: Einstein’s Tutor, by Lee Phillips.
The title refers to Noether’s significant influence on Einstein’s efforts to mathematically formulate his ideas of general relativity. Einstein was not a strong mathematician, so he ended up turning to the mathematicians at the famed University of Göttingen for help. This included Emmy Noether, who was one of several that Einstein turned to; the other was the famous and brilliant David Hilbert.
I’ve had a pretty long career in physics, optics in particular, at this point: I have published over 150 peer-reviewed papers and have written 5 books. Looking back to the start of my journey in science, I don’t think I could’ve imagined how much I would do. With that in mind, I was recently thinking back to my very first paper — published in 1997, almost thirty years ago — and I thought it would be fun to talk about the paper and its influence on my career.
So here is the title and abstract of the paper:
The “Emil Wolf” in this case was my PhD advisor, one of the most distinguished optical scientists of the modern era. His book Principles of Optics, co-authored with Max Born and commonly just known as Born and Wolf, is one of the most cited scientific texts out there, with some 81,000 citations according to Google Scholar.
Book 19 for my 2025 goal of 30 books for the year! As is now default for me, my link to the book is through my bookshop dot org affiliate account.
Last month, I read the first book in John Christopher’s classic young adult science fiction series The Tripods, and was sufficiently intrigued and entertained to pick up the second book, The City of Gold and Lead (1967).
The first book in the trilogy, The White Mountains, leaves the origins of the tripods and their true nature mysterious, and the novel is more of a post-apocalyptic road trip story than a full science fiction tale. The second book steps fully into science fiction, as the protagonist goes on a mission into one of the mega-cities of the tripods in an attempt to find information that can eventually defeat them.
Book 18 for my 2025 goal of 30 books for the year! As is now default for me, my link to the book is through my bookshop dot org affiliate account.
Ramsey Campbell still knows how to catch me off guard. The first chapter of his latest novel An Echo of Children starts with grandparents visiting their children and grandson at their new house in the seaside town of Barnwall. Everything seems very mundane throughout, though there is a bit of tension in the house that eventually gets traced to the grandson Dean having an imaginary friend. That in itself is not terribly worrying, until Dean lets slip a completely unexpected and shocking comment about this imaginary friend.
This is what I’ve come to expect and love about the works of Ramsey Campbell, who I have written about many times on this blog. His stories tend to be a slow burn, with dread building up slowly and inexorably, leaving the reader with the uncomfortable awareness that something is very wrong but unsure of exactly what that is. Even the moments that catch me off guard, like the end of the first chapter of An Echo of Children, is in service towards establishing that dread and uncertainty.
The book comes out in September; Flame Tree Press was kind enough to provide me an ARC of the book to read and review in advance.
Book 17 for my 2025 goal of 30 books for the year! As is now default for me, my link to the book is through my bookshop dot org affiliate account.
Before there was The Hunger Games, or Divergent, there was John Christopher’s The Tripods, a series of young adult novels about teenagers struggling against a powerful oppressive force in a science fiction dystopia. In one of my random searches on the internet, I came across a reference to the series, and was immediately intrigued enough to go read the first book for myself. That book is The White Mountains (1967), which is still in print today.
Book 16 for my 2025 goal of 30 books for the year!
The year is 1923. Veronica Brinkley is landing on the moon to get psychiatric treatment at the Barrowfield Home for the Treatment of the Melancholy.
You didn’t read that wrong: she’s landing on the actual moon for psychiatric care in 1923. This is the beginning of the surreal Gothic fantasy Crypt of the Moon Spider, by Nathan Ballingrud, released last year.
I’ve been brushing up on my quantum physics and quantum information science lately, and thought it would be good practice for me to give a little introduction to the idea of quantum cryptography, and one of the first strategies proposed to do it. “Cryptography,” of course, refers to sending coded messages between two people, and the “quantum” part refers to using the inherent properties of quantum physics to make messages harder to crack. This post, then, will be a little bit about the concepts of cryptography and a little bit about the concepts of quantum physics.
We’ll talk about the first protocol for such quantum cryptography first introduced by Bennett and Brassard in 1984, referred to as the BB84 protocol1. My discussion follows my recent read of Stephen Barnett’s book on Quantum Information, which is a very good introduction for physics folks with some background in math and quantum mechanics. The description here, however, will be my own understanding and interpretation, subject to my own still growing understanding of the subject.
Book 15 for my 2025 goal of 30 books for the year! Had a significant hiatus of reading due to life stresses, but still ahead on my goal.
Zombies are everywhere in fiction these days, from The Last of Us to 28 Years Later to The Walking Dead and more. There was a time, back in the Night of the Living Dead days, when zombie stories were somewhat of a niche subject and everyone probably thought that they’d go out of fashion and be forgotten. On the contrary, zombie stories alone have become a mainstay of horror, their own enduring subgenre.
This is why Mindy Weisberger’s recent book, Rise of the Zombie Bugs, is incredibly timely and fun. Though zombification of humans like in the movies appears (for the moment) to not be a thing, it turns out that zombification is a surprisingly common thing among the “bugs.”
Small disclaimer: I’m a longtime friend of Mindy’s, and am acknowledged in the book for providing “bookish wisdom” (though I’m not sure that I was particularly helpful). Also, because we’re friends, it will be weird for me to call her Weisberger through this post, so I’ll stick to Mindy.
The author of Skulls in the Stars is a professor of physics, specializing in optical science, at UNC Charlotte. The blog covers topics in physics and optics, the history of science, classic pulp fantasy and horror fiction, and the surprising intersections between these areas.
Skulls in the Stars 