HORIZONTAL VIEWS

In “A Tale of Two Horizons,” Edgar Shaghoulian provides an intriguing alternative view of black holes and our entire cosmos as well. Especially of interest is his statement that “we must find a way to look at the cosmic horizon from the outside.” Yet that assumes there is an outside. Moreover, if one does exist, what is outside of that?

I am afraid we anthropomorphize the universe when attempting to describe it in familiar terms such as in the holographic principle. Our observations require an observer—us. We use our senses and employ instruments whose measurements must ultimately also depend on our interpretations. Perhaps it is human hubris, which knows no bounds. Our species evolved in order to survive on Earth, not to understand the cosmos. Perhaps the universe is not only stranger than we understand; it may be stranger than we can understand.

BARRY MALETZKY Portland, Ore.

SHAGHOULIAN REPLIES: I am a perennial optimist: our ability to understand quantum mechanics and Einstein’s general theory of relativity far beyond what is needed evolutionarily gives me hope that we will understand the cosmos as well. Whether there is really an “outside” of the cosmic horizon is a tricky question. The equations suggest that it’s there. But historically, it has sometimes been argued to be metaphysical because measuring the existence of something requires interacting with it, and by definition, we cannot receive signals from beyond our event horizon. This is why some of us find the potential nonlocal connections between the two sides of an event horizon so intriguing: we will be able to access what was once thought of as forever lost.

PRESERVING INFORMATION

Thank you for “Paradox Resolved,” George Musser’s article on the black hole information paradox. I have questions that look not forward toward the principle used to crack that paradox but rather backward: As Musser describes, the laws of physics require that the information needed to reverse anything that happens in the physical world is always preserved. Does this information preservation principle imply that all information was already in existence in the big bang singularity? And if information has only been created after the big bang, does such an information increase then reduce entropy?

G. RHINE Philadelphia

MUSSER REPLIES: This is an extremely perceptive question. Information preservation is a synonym for determinism. All that happens now was set at the big bang—or indeed at any other moment (there is no reason to assume it must be in the past). This comes with the important caveat that the information we’re talking about is the global quantum state, which evolves according to the Schrödinger equation. But any subsystem of the universe will see information generation or destruction.

THE TURING TEST LIVES

In “AI Writes about Itself,” Almira Osmanovic Thunström describes how she and her colleagues instructed the artificial-intelligence algorithm GPT-3 to write a scientific paper with itself as the subject. As I read the article, it came back to my mind that, in the 1980s, a colleague of mine wrote a toy program: with half a dozen randomly chosen words as input, it produced a text that was syntactically correct. He had named the program “bullshit generator.”

PIER GIORGIO INNOCENTI
Grand-Saconnex, Switzerland

I have been reading Scientific American and other noted science magazines for decades, and Thunström’s article about GPT-3 writing an academic paper about itself was among the most fascinating because it raises new issues that many of us have never considered before. Certainly the ethical issue of nonsentient authorship is the most absorbing. And of course, the impact on who gets credit for what will occupy the minds of some scientists because academia is so competitive.

Use of this algorithm might begin to change everything about how we value creators of ideas, not just papers. I am also impressed with how GPT-3’s use of language was so human-sounding. It seems like it could pass the Turing test.

ROBERT WALTY
Stephens City, Va.

NOVEL EXPERIENCE

Thanks for including works of fiction in your book reviews. I see the September column has an appreciation of a reissued classic by Octavia E. Butler in “A Time Traveler’s Legacy” [Reviews]. But I have noticed fairly regular fiction reviews over the past year or so—something I don’t recall in many issues over the past 50-odd years. (Is my memory playing tricks on me, or did Scientific American include a review of Thomas Pynchon’s Gravity’s Rainbow in 1973?) As an old English major with a curious layperson’s interest in science, I appreciate this broadening of the kinds of books you recommend to your readers.

JAMES YARNALL Pisgah Forest, N.C.

THE EDITORS REPLY: Yarnall’s memory is sound: our longtime book review editor Philip Morrison wrote about Gravity’s Rainbow in our October 1973 issue.

ENERGY INFRASTRUCTURE

It is misleading for the Editors to say the time is right for “Electrifying Everything” [Science Agenda; July 2022]. Currently our electricity sources are only fractionally renewable. A higher priority is reducing the carbon content of the grid while improving its reliability.

As we move to more renewables, we are going to need technology for storing energy. Batteries are great for some things, but nature stores energy in chemical form. We have biofuels and hydrogen now, and technology has to advance only a little for making renewable methane—which could be used perfectly in existing natural gas infrastructure and serve as a bridge to an actual all-electric future.

MAX SHERMAN
Retired senior scientist, Lawrence Berkeley National Laboratory

CONTINENTAL COINCIDENCE

I noticed an artful and odd coincidence in “Dynamic Seas,” by Mark Fischetti, Kelly J. Benoit-Bird, Skye Morét and Jen Christiansen [Discoveries from the Deep; August 2022]: At the center of the “Conveyor Belt” infographic is Antarctica. The continent is surrounded by all the world’s oceans, with red and blue lines showing warm and cold major ocean currents. The layout of the world’s oceans resembles a surprising replica of the shape of Antarctica itself.

DUNCAN CLARK
via e-mail

ERRATA

“Protecting Kids’ Mental Health,” by Mitch Prinstein and Kathleen A. Ethier [Forum], should have said that in 2019 about one in five high school students surveyed seriously considered suicide and that about one in 11 attempted suicide, not that about one in five seriously considered or attempted suicide.

“Testing Nukes,” by Adam Mann and Alastair Philip Wiper [October 2022], should have said that “some” of the $15 billion a year the nation spends to research and test nuclear material goes to the National Ignition Facility (NIF) at Lawrence Livermore National Laboratory, not “much” of that amount. The NIF’s current yearly budget is $349 million.

“Saving the Night Sky,” by Joshua Sokol [October 2022], should have described the blue-white light fixtures used in an experiment in New York City housing developments starting in 2016 as left on from sunset to sunrise, not sunrise to sunset.