The Beyond-Spacetime Meme

How do you illustrate a column on what lies beyond space and time? I decided that this photo of the carpet in my office will do just fine.

A REALM BEYOND SPACETIME [A.K.A. HOBOKEN, NJ, OCTOBER 3, 2024]. Decades ago, I coined the phrase ironic science to describe theories that shouldn’t be taken too seriously, because they can’t be tested as genuine science can. Ironic science is more akin to philosophy or literature than real science. An ironic theory, like Freudian psychoanalysis, might be interesting, fun to argue over, but you can never say it’s true.

That brings me to “The Unraveling of Space-Time,” a special issue of Quanta Magazine. This bundle of articles explores the possibility that space and time, which Einstein fused into spacetime, emerge “from more primitive building blocks that don’t themselves inhabit space and time.”

For brevity, and levity, I’ll call this notion the beyond-spacetime meme. The meme isn’t exactly new, as Quanta acknowledges and as the invaluable physics watchdog Peter Woit points out on his blog “Not Even Wrong.” The beyond-spacetime meme is linked to physicists’ quest to find a unified theory describing all of nature’s forces.

A unified theory would reconcile general relativity, Einstein’s theory of gravity, with quantum theory, which accounts for electromagnetism and the nuclear forces. General relativity and quantum theory are written in incompatible mathematical languages, which yield divergent views of space, time and causality.

For 40-some years, string theory has been touted as the most promising unified theory. Edward Witten, whom I once called the “Pied Piper” of strings, surely had something like the beyond-spacetime meme in mind in 1991 when he told me he was seeking the “core geometric principles” underpinning strings.

The problem, you guessed it, is that neither string theory nor other candidates for a unified theory make testable predictions. They traffic in mathematical thingamabobs supposedly inhabiting the Planck scale, which is zillions of times too tiny to be probed by real-world experiments.

Yeah, testability remains a problem, string apologist Brian Greene now concedes in The Washington Post, but string theory is still worth pursuing, because it “has yielded provocative insights into long-standing mysteries and introduced radically new ways of describing physical reality.” Peter Woit rebuts Greene’s claim here.

When I pressed Edward Witten on testability in 1991, he responded: “I don’t think I’ve conveyed to you [string theory’s] wonder, its incredible consistency, remarkable elegance and beauty.” String theory, Witten meant, is so mathematically compelling that it must be true, or at least on the right track.

Other physicists defend their favorite beyond-spacetime hypotheses with similar arguments. But as physicist Sabine Hossenfelder points out, subjective criteria like “beauty” and “elegance” are no substitute for hard data from accelerators and other sources.

Here’s another problem: To what extent can any beyond-spacetime theory predict or explain anything? Philosopher of physics Tim Maudlin raised this objection after I posted a link to the Quanta issue on Facebook.

“Our entire experience of the physical world presents itself as objects with spatial structure moving around as time goes on,” Maudlin says. A theory devoid of space and time “cannot make contact with what we regard as ‘evidence’ or ‘observation.’”

I raised a similar gripe about string theory in The End of Science, because no physicist could explain to me exactly what a string is. A string, I whined, seems to be “some kind of mathematical ur-stuff that generates matter and energy and space and time but does not itself correspond to anything in our world.”

Oh, and keep this in mind: Most physicists assume a unified theory, whether or not it transcends spacetime, will be a quantum theory. And we still don’t know what quantum mechanics means!

The beyond-spacetime meme, I can’t resist mentioning, popped up last month at “Sages & Scientists,” a three-day symposium overseen by spirituality/health guru Deepak Chopra. I moderated a session in which Chopra and four scientists proposed that consciousness—rather than matter, space and time—is “the fundamental reality.”

Before you scorn that idea as too woo, check out this marvelous Quanta essay by physics writer Amanda Gefter. She notes that John Wheeler, one of the most influential physicists of the 20th century, conjectured that consciousness is fundamental.

Wheeler’s proposal sprung from his contemplation of the double-slit experiment and other probes of the quantum realm; different experimental set-ups yield different results. We live in a “participatory reality,” Wheeler concluded, in which our questions define our world and even to a certain extent bring it into existence.

Wheeler agonized over this perspective, Gefter shows, because he couldn’t reconcile the possibility that each of us inhabits a different subjective reality with his conviction that we all live in the same material world. Yeah, how can subjectivity and objectivity be reconciled? Good question, with which philosophers have grappled for millennia.

When I call beyond-spacetime speculation “ironic science,” am I suggesting that it’s worthless and should be abandoned? Hell no, for several reasons:

First, technological advances can enable scientists to solve once-intractable riddles, like What are stars made of? and Did our universe have a beginning? Maybe someday kindly, supersmart aliens will lend us gadgets that can probe the Planck scale and detect other universes (all multiverse theories are ironic). Who knows?

Second, ironic science can be fruitful. Although string theory hasn’t told us anything about the real world, it has spurred mathematical advances. Edward Witten hasn’t won a Nobel Prize, but he won the highest honor in math, the Fields Medal. And John Wheeler’s suggestion that reality is defined by bits, answers to yes-or-no questions, spawned the thriving field of quantum information theory.

Third, I love ironic science! Just as I love Plato’s parable of the cave and Moby Dick. At its best ironic science, like great works of philosophy and art and even great science journalism, slashes through our habituation and rubs our face in the weirdness of things we take for granted. And is there anything we take for granted more than space and time?

So read about “the unraveling of space and time” in Quanta. But read with a smile, don’t take all the jibber-jabber about the holographic universe or black hole thermodynamics or AdS/CFT duality too seriously. Because all the beyond-spacetime speculation, no matter how mathematically compelling, isn’t science. It’s ironic science.

Further Reading:

For excellent primers on beyond-spacetime speculation related to quantum mechanics and consciousness, respectively, check out these two books by physics writer George Musser: Spooky Action at a Distance; and Putting Ourselves Back in the Equation. See also Musser’s interview with philosopher Tim Maudlin, “A Defense of the Reality of Time.”

For more of my skeptical takes on physics, see Physicists Teleport Bullshit Through “Wormhole”!, Multiverses Are Pseudoscientific Bullshit, The Ironic Interpretation of Quantum Mechanics, Is the Schrödinger Equation True?, Quantum Mechanics, the Chinese Room and the Limits of Understanding and my free, online book My Quantum Experiment.