Is Spacetime Doomed?

In cutting-edge physics and philosophy, a provocative theme has gained traction: “spacetime is doomed.” Leading thinkers argue that space and time are not fundamental ingredients of reality, but rather emergent phenomena or useful illusions. This report explores why many physicists and philosophers believe spacetime is not fundamental, examining evidence from quantum gravity research (like holography and the amplituhedron), experimental challenges to locality and realism, philosophical models that put consciousness or information at the core of reality, and the sociological factors influencing acceptance of new paradigms. We also consider counterpoints – what mainstream science still affirms about spacetime and where debates remain open.

Developments in Physics Hinting Spacetime Isn’t Fundamental

Quantum Gravity and the Breakdown of Spacetime

Modern physics faces “storm clouds” at the Planck scale, where combining quantum mechanics and general relativity causes familiar notions to break down (The Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-Hamed). If we try to probe extremely small distances, gravity intervenes by creating black holes that prevent any measurement inside them . This suggests that treating spacetime as a smooth continuum beyond a certain scale is futile – our current spacetime picture is only an approximation . As physicist Nima Arkani-Hamed bluntly puts it, “We’ve known for decades that space-time is doomed… we know it is not there in the next version of physics” (Amplituhedron May Shape the Future of Physics | Discover Magazine). In other words, a successful theory of quantum gravity likely cannot take spacetime as a given backdrop – instead, spacetime itself must emerge from deeper structures . This viewpoint is reinforced by singularities in general relativity (like the cores of black holes) where spacetime curvature becomes infinite and physics as we know it breaks, hinting that a more fundamental description is needed.

One powerful hint comes from black hole thermodynamics and the holographic principle. Studies of black hole entropy showed that the maximum information (entropy) in a region of space grows with the area of its surface, not its volume. This led to the idea that the physics inside a volume can be encoded on its boundary – akin to a hologram. In 1997, Juan Maldacena’s AdS/CFT correspondence made this concrete: a fully quantum gravitational world in a 3D spacetime can be exactly dual to a 2D quantum field theory with no gravity on its boundary. In such a duality, the “bulk” spacetime is not fundamental at all; it emerges from the quantum degrees of freedom on the boundary. Indeed, Mark Van Raamsdonk showed that if you gradually remove entanglement between parts of a quantum system, the connected spacetime “pulls apart” and breaks into disconnected pieces ([1005.3035] Building up spacetime with quantum entanglement). His work argues that “the *emergence of classically connected spacetimes is intimately related to the quantum entanglement of degrees of freedom” . In short, entanglement – a quantum link outside classical space – seems to stitch space together. Recent reviews highlight that spacetime and even Einstein’s gravity could emerge from patterns of entanglement in a deeper quantum reality (Spacetime from Entanglement | Annual Reviews). If true, our smooth spacetime is like a network woven by quantum threads of entanglement.

Another clue comes from quantum field theory and scattering amplitudes. Arkani-Hamed and colleagues discovered a jewel-like geometric object, the amplituhedron, which encodes particle collision outcomes without using space or time in the computation (A Jewel at the Heart of Quantum Physics | Quanta Magazine). In traditional particle physics calculations, one assumes particles move through spacetime and interact locally, enforcing locality (no action at a distance) and unitarity (probabilities sum to one). Remarkably, the amplituhedron generates the same predictions by geometric volume calculations, and features like locality and unitarity emerge as properties of the geometry’s facets rather than being put in by hand. As Quanta Magazine reported, “The amplituhedron is not built out of space-time and probabilities; these properties merely arise as consequences of the jewel’s geometry. The usual picture of space and time, and particles moving around in them, is a construct.” . This suggests that the familiar spacetime-based description is like a shadow of a deeper, timeless mathematical structure. In fact, Arkani-Hamed believes this line of research is a step toward giving up space and time as fundamental: the hope is to explain cosmology (the Big Bang, etc.) “out of pure geometry,” where change comes from the structure of a timeless object . In such a framework, spacetime would be an emergent approximation, similar to how a flowing liquid emerges from discrete molecules. (Below is an artistic rendering of the amplituhedron, illustrating how a complex geometry might underlie particle interactions.)

Illustration of the amplituhedron, a multi-faceted geometric object. It encodes particle scattering amplitudes without reference to spacetime – hinting that locality and time might be emergent rather than fundamental (A Jewel at the Heart of Quantum Physics | Quanta Magazine).

Various quantum gravity theories pursue the idea of emergent spacetime. Loop Quantum Gravity, for instance, quantizes space itself into discrete chunks. It replaces the smooth fabric of space with a fine network of quantum threads called spin networks – giving space an atomic structure. In loop gravity, area and volume have discrete spectra, implying a smallest possible unit of length (on the order of the Planck length). The continuum of spacetime is then a large-scale illusion, arising from countless quanta of space. Other approaches like causal set theory posit that spacetime is fundamentally a discrete set of events with only causal relationships, which, when coarse-grained, looks like the spacetime we know. Even string theory – often seen as a theory set in spacetime – has yielded surprises that point to emergent space: for example, in AdS/CFT the extra spatial dimension of the bulk is emergent, and in certain string models space can emerge from matrix-like degrees of freedom. These diverse approaches all reflect a growing consensus that spacetime, as a continuous manifold, cannot be the starting point of a unified physics theory (Amplituhedron May Shape the Future of Physics | Discover Magazine). Instead, it should arise from something else (whether quantum information, algebraic geometry, or discrete combinatorial data). As Arkani-Hamed emphasizes, new principles are likely to replace spacetime and even quantum mechanics at the fundamental level , with both emerging together from a deeper theory.

Experimental Evidence Challenging Local Realism

If spacetime is not fundamental, one expectation is that nature might betray spacetime-based intuitions – and indeed it does. Quantum entanglement experiments have decisively violated local realism, the notion that objects have definite properties and no influence can travel faster than light (The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific American). In a locally real world (as Einstein imagined), what happens here should not instantly affect something over there, and physical properties should exist whether or not we observe them. But experiments beginning in the 1970s (and refined through the 2010s) show the opposite. Pairs of particles can be entangled such that measuring one seems to instantaneously influence the other, no matter the distance. In 2022, Alain Aspect, John Clauser, and Anton Zeilinger earned the Nobel Prize in Physics for a series of ingenious tests confirming that no local hidden-variable theory can explain quantum correlations . These Bell test experiments closed loopholes one by one, and the verdict is clear: the universe cannot be both local and have observer-independent properties. As Scientific American put it, “the universe is not locally real” – an object may not have a single definite state prior to measurement, and separated objects can display holistic connections that transcend spatial separation.

These experimental facts align with the idea that spacetime is an emergent construct. If particles are fundamentally entangled across space, it suggests a layer of reality where distance is irrelevant or profoundly different from our classical picture. Some physicists even connect this to geometry: a conjecture called ER = EPR (proposed by Leonard Susskind and Juan Maldacena) speculates that every pair of entangled particles (EPR pair) is connected by a tiny non-traversable Einstein-Rosen bridge (ER, or wormhole). In this view, entanglement and spacetime geometry are two sides of the same coin – spacetime might literally be built from quantum connections. Recent experiments have taken a step toward this idea: In 2022, researchers simulated a traversable wormhole on Google’s quantum computer by exploiting entanglement. They successfully sent a quantum message between two entangled systems in a way mathematically analogous to sending it through a small wormhole (Physicists Create a Wormhole Using a Quantum Computer | Quanta Magazine). As one of the lead scientists stated, “gravity in our universe is emergent from some quantum bits in the same way that this little wormhole is emergent” from the quantum system. While these are preliminary results, they dramatize the core idea: space, distance, and perhaps even gravity itself might arise from quantum informational relationships. Entanglement experiments thus chip away at “spacetime realism” – suggesting that what’s fundamental is not localized matter moving through spacetime, but something deeper (nonlocal waves, information, etc.) that only project the illusion of classical space and time.

Not only do these quantum phenomena challenge locality, they also challenge a purely material ontology. If observation and information are central (as quantum theory implies), one might argue that spacetime and matter are interface-like, with information as the deeper reality. In fact, over 30 years ago John Wheeler anticipated this with his famous dictum “It from Bit.” Wheeler suggested that every physical thing (“it”), even the spacetime continuum itself, derives its meaning and existence entirely from binary answers (“bits”) to yes-or-no questions posed by observers (John Archibald Wheeler Postulates "It from Bit" : History of Information) . In his view, at microscopic scales “there is no such thing as space or time or spacetime continuum” – those are convenient continuum idealizations. Reality, at root, might be information-theoretic and participatory . The Nobel-winning entanglement experiments strongly echo Wheeler’s idea, showing that information (the measurement outcomes and their correlations) is more fundamental than naive spatiotemporal causality.

Holographic and Information-Theoretic Models

The holographic principle mentioned above generalizes the notion that spacetime emerges from information. In a holographic universe, what we experience as volume, location, and perhaps even the flow of time could be like a 3D movie projected from data on a distant 2D screen. The AdS/CFT duality provides a concrete example: a quantum system without gravity (essentially living in a fancy “flat” world of bits) can give rise to a dynamic spacetime with gravity. With ideas like tensor networks, physicists have constructed toy models of emergent space: a web of entangled qubits can be mapped to a discrete curved space geometry (Spacetime from Entanglement | Annual Reviews). If a smooth limit exists, this emergent geometry obeys Einstein’s equations of general relativity . In this view, spacetime = geometry of entanglement. The fabric of space is woven from the quantum correlations among underlying degrees of freedom. This line of thought has opened new avenues in quantum gravity research (sometimes called “It from Qubit” programs ( Is Space-Time Really Doomed? | Not Even Wrong )) focusing on quantum information as the source of spacetime structure.

John Wheeler’s “it from bit” is a broader information-centric vision: reality is essentially information, and what we call space and time are constructs that emerge from a vast network of yes/no questions and answers . An everyday analogy is how a computer generates a virtual 3D world from binary code: the landscape in a video game is not fundamental – it’s rendered from the underlying bits when observed. Similarly, our universe’s spacetime might be “rendered” from a deeper informational substrate when we, as participatory observers, interact with it. This approach overlaps with digital physics and simulation hypotheses – the idea that the universe could be akin to a giant computation. While speculative, it provides a conceptual bridge between quantum physics and spacetime: instead of little billiard-ball particles in space, the core reality could be quantum information itself, with spacetime as a secondary, derived concept.

Philosophical and Consciousness-Based Frameworks

The radical reconsideration of spacetime’s status has also resonated with certain philosophical models. If spacetime and matter are not fundamental, what is? Some argue that mind or consciousness could be the foundational stuff of reality, with the physical world (including spacetime) as an emergent appearance. This is a form of idealism updated with modern science. One of its vocal proponents is cognitive scientist Donald D. Hoffman. Hoffman notes that evolutionary pressures favor useful perceptions, not true reality. He proposes that spacetime is merely a species-specific “user interface” – a convenient graphical interface that our minds use to interact with an underlying reality far more complex (and not spatial or temporal in itself). Just as a computer’s desktop interface shows colorful icons (which bear no resemblance to the actual electronic circuits and binary code underneath), our perceptions of objects in space and time are like icons that let us survive and reproduce, without revealing the true underlying “code.” Hoffman bluntly says: “Physics is not fundamental. Spacetime is not fundamental. Consciousness is. What we call physical objects are merely the ways that we play with our interface… into the realm of conscious agents.” (Professor Donald Hoffman — The Case Against Reality, Beyond Spacetime, Rethinking Death, Panpsychism, QBism, and More (#585) - The Blog of Author Tim Ferriss). In his model, networks of conscious agents interacting with each other give rise to the emergent world of spacetime and physical objects that we observe . Thus, spacetime is “doomed” in the sense that it disappears when you peek behind the interface – much like the file icon on your screen ceases to have meaning if you dig into the machine code.

This approach aligns with a long philosophical tradition (going back to Bishop Berkeley’s idealism, and more recently to doctrines in Eastern philosophy) that the physical world is Maya or illusion, and mind is fundamental. What’s new is that scientists like Hoffman tie this to physics and evolution, and even cite physics luminaries in support. For instance, Hoffman often quotes Arkani-Hamed’s statement that spacetime is doomed, taking it as corroboration that even physicists realize space and time cannot be ultimate. His own mathematical work on conscious agents seeks to show how the dynamics of consciousness, when projected into a “spacetime interface,” could produce the structures we see in quantum physics and relativity () (). There is speculative research along these lines: e.g. models where quantum probabilities arise from interactions of observer-like entities, or where time’s flow is an artifact of an underlying timeless process among mental events ().

Beyond Hoffman, there are other consciousness-centric models. Some philosophers (e.g. Bernardo Kastrup) advocate analytic idealism, arguing that the universe is essentially a single universal consciousness and what we call spacetime and matter are dissociated mental processes within that mind. In such views, spacetime might be akin to a “data structure” that consciousness uses, not fundamental scaffolding. Others consider panpsychism, the idea that even elementary physical processes have proto-conscious aspects – potentially blurring the line between what is physical and what is experiential. While panpsychism usually doesn’t dispense with spacetime, it does challenge the strictly materialist picture and opens the door to mind-based ontologies.

It’s worth noting that these consciousness-based interpretations remain highly controversial. Most physicists do not invoke consciousness in fundamental theories. However, the mere fact that mainstream physics admits spacetime might be emergent has emboldened some to ask: could conscious experience be part of the more fundamental layer from which spacetime springs? Hoffman’s work, for example, while speculative, is published and engages with both cognitive science experiments and mathematical modeling of dynamical systems beyond space and time () (). Even if one is not ready to accept “consciousness is fundamental,” such ideas highlight that our assumptions about reality (e.g. the primacy of the physical world, spacetime, and objects) are being scrutinized. The common thread with physics approaches is the notion of emergence: spacetime emerges from something else. Whether that something else is quantum information, geometric combinatorics, or a vast interacting network of conscious minds, the implication is that spacetime is derivative. It is an interface or stage on which phenomena play out, not the machine code of reality.

The Role of Scientific Institutions and Paradigm Shifts

If spacetime is indeed “doomed” as a fundamental concept, it marks a paradigm shift in physics. History shows that such deep shifts often encounter resistance and take time to be embraced. Scientific institutions – journals, funding agencies, university curricula – are often conservative, favoring established frameworks. Paradigm changes (in Thomas Kuhn’s sense) can be delayed not just by lack of evidence but by human factors. A classic example is the initial reception of Einstein’s theories. When Einstein proposed special relativity (1905) and general relativity (1915), they faced skepticism. Only after British astronomers Eddington and Dyson confirmed general relativity’s prediction of starlight bending in the 1919 eclipse did Einstein’s ideas gain broad acceptance. Even then, older scientists like Philipp Lenard refused to accept relativity for years. Quantum mechanics too was resisted by some of its discoverers – famously, Einstein himself never fully accepted the loss of determinism and locality, encapsulated in his question “Do you really believe the Moon is not there when you are not looking at it?” (The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific American). These are reminders that human intuition and habit cling to old concepts (absolute space and time, definite reality) long after experiments have overturned them.

Max Planck noted this sociological inertia wryly: “A new scientific truth does not triumph by convincing its opponents… but rather because its opponents eventually die and a new generation grows up that is familiar with it.” (Planck's principle - Wikipedia) In colloquial terms, science advances one funeral at a time. If spacetime is being supplanted by new ideas, it may take a generation of researchers trained in those ideas to fully establish the new paradigm. We see institutional conservatism even in recent times. For decades (roughly 1940s–1980s), research on the foundations of quantum mechanics – things like Bell’s theorem, entanglement, questioning locality – was considered fringe or even career suicide (The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific American). Mainstream physicists advised students against working on these questions, and major journals often rejected such papers as too philosophical . It took persistent work by Aspect, Clauser, Zeilinger and others, often on the margins of mainstream projects, to produce results that eventually won the Nobel Prize and forced the community to take quantum foundations seriously. This shows that even when nature herself is providing clues (like violations of Bell’s inequalities), the community can be slow to listen if the clues challenge deeply held assumptions (like local spacetime realism).

Today, the idea that spacetime might not be fundamental is still not a majority view among working physicists, though it’s arguably a leading-edge view gaining momentum. Large experimental programs (the LHC, gravitational wave observatories, etc.) still operate entirely within the spacetime formalism of relativity and quantum field theory. Grants and curricula largely focus on refining known physics, not rebuilding the conceptual foundation. That said, top institutions and visionary scientists are carving out space for the “beyond spacetime” research: for example, the It from Qubit collaboration (backed by the Simons Foundation) explicitly brings together quantum information scientists and quantum gravity theorists to explore emergent spacetime ideas ( Is Space-Time Really Doomed? | Not Even Wrong ). Prestigious lectures (like Arkani-Hamed’s Messenger Lectures at Cornell in 2010, titled “Space-Time is Dead”) and conferences are disseminating the notion. We are likely in the early phase of a paradigm shift – where multiple converging lines of inquiry (scattering amplitudes, holography, quantum information, etc.) point to the same astonishing conclusion, but a fully fleshed-out theory is not yet in hand. During such times, the scientific establishment is rightly cautious: extraordinary claims demand extraordinary evidence and, importantly, a robust theoretical framework that can replace the old one and still calculate known phenomena. Currently, “spacetime is doomed” is a slogan motivating research rather than a completed theory, and so healthy skepticism persists among many physicists.

Historically, when paradigm shifts do occur, they often unlock new technologies and insights. For instance, quantum mechanics – once seen as bizarre and impractical – became the bedrock of the semiconductor and laser revolutions. Likewise, if spacetime being emergent is more than a mathematical quirk, the eventual new framework might enable technologies previously thought impossible.

Technological Implications of a Post-Spacetime Paradigm

While still speculative, one can envision profound technological (and societal) implications if spacetime is not fundamental. For one, understanding the mechanism by which spacetime emerges could give us control over that mechanism. If entanglement patterns create geometry, perhaps one day we could engineer those patterns to shape spacetime itself. This might sound like science fiction, but even a modest example is exciting: researchers are already speculating about quantum networks that take advantage of entanglement to transfer information in ways that don’t neatly respect classical distance. A future quantum internet could use distributed entangled nodes such that information security and transmission achieve feats impossible in a spacetime-bound classical network. Quantum teleportation (which is real, albeit of quantum states rather than matter) and quantum encryption are direct fruits of non-spacetime correlations. As our mastery of entanglement grows, who knows – we might effectively “route” information outside the normal space-time continuum (again, not in a sci-fi faster-than-light signaling way, but in ways that leverage the underlying connectivity of quantum reality).

In computing, a framework beyond spacetime might lead to novel architectures. Quantum computing already hints at this: qubits in superposition and entanglement perform computations in a manner that defies classical spatial localization. Some researchers even describe quantum algorithms as taking shortcuts through an abstract computation space that is not constrained by ordinary geometry. If spacetime is an emergent approximation, a powerful quantum computer might be seen as a device that computes below that layer, directly on the “source code” of reality (the Hilbert space, or some deeper structure). As one example, the amplituhedron has drastically simplified certain particle interaction calculations (A Jewel at the Heart of Quantum Physics | Quanta Magazine) – perhaps future computers (or advanced AI mathematicians) will leverage such geometric structures to simulate physical processes far more efficiently than by brute-force simulation of quantum fields in spacetime. This could open the door to simulating universes or solving otherwise intractable physics problems by working in the “native language” of the deeper theory.

If consciousness or information is fundamental, as some propose, then interfaces with that realm could revolutionize technology. Imagine if minds (or conscious agents) are part of the fabric that gives rise to spacetime. Technologies might be developed to directly interact with consciousness at a fundamental level, leading to what today would be labeled telepathy or psychokinesis – but underpinned by scientific principles of a post-materialist physics. Even short of that, an idealist framework could inspire new approaches in artificial intelligence and cognitive science, treating physical substrates as secondary. At minimum, it encourages a more holistic view of information processing that doesn’t separate mind and matter as categorically as before.

On a more concrete level, if spacetime is emergent, it raises the possibility of manipulating the emergent phenomenon in new ways. For instance, warp drives or wormhole travel – staples of sci-fi – require “bending” spacetime in exotic ways. Mainstream relativity finds this nearly impossible without negative energy, etc. But if spacetime is a kind of condensate or hologram, perhaps there is a way to “program” a shortcut. A tantalizing example is recent work on traversable wormholes: theoretical physicists have shown that in certain quantum gravity models, entangled black holes can mimic a tunnel where information actually crosses from one to the other. While we are far from any practical wormhole travel, the key point is that space is not immutable. It’s something that can, in principle, be altered or even created/annihilated. Future technologies may exploit this by operating at the level of quantum information.

Lastly, a post-spacetime paradigm might yield insights into unifying physics that lead to applications. For example, a quantum theory of gravity could unify forces and perhaps pave the way to harnessing gravity or inertia (think inertial dampeners or artificial gravity). If spacetime geometry and quantum fields unify, we might discover new states of matter or energy. Already, concepts like time crystals (periodic structure in time) or spacetime metamaterials are being explored at a theoretical level. They hint that by treating time and space as malleable parameters, we could design materials with unprecedented properties (like always-in-motion stable states, or ultrafast information propagation).

In summary, while practical applications are speculative, the mere shift in worldview – that space and time are emergent – can be revolutionary. It invites us to question limits that were once thought absolute. Technologies that manipulate the fabric of reality at a deeper level could transcend what we now consider possible in communication, computation, and transportation. Of course, all such possibilities rest on future scientific breakthroughs. For now, they serve as motivation: just as the quantum revolution led to lasers and transistors, a spacetime-emergent revolution could eventually yield transformational tools by leveraging the layer beneath spacetime.

Counterpoints and Ongoing Debates

Despite the enthusiasm in some quarters, it must be underscored that spacetime is still an extraordinarily successful framework. General relativity and quantum field theory (QFT) – the pinnacles of 20th-century physics – both assume a form of spacetime (curved or flat) and have been validated to extreme precision in their domains. GPS satellites must account for relativistic time dilation (a testament to spacetime’s reality), and particle colliders rely on QFT calculations (assuming spacetime continuum) that predict outcomes to many decimal places. Any new theory where spacetime is emergent must reproduce these successes in the appropriate limit. So far, no emergent-spacetime model has fully recovered all of known physics in a complete, quantitative way. Skeptics therefore view “spacetime is doomed” as more slogan than substance – a promissory note that has yet to be paid. Peter Woit, a physicist and commentator, has noted that Arkani-Hamed’s use of the phrase is mostly motivational, and that it’s unclear how abandoning spacetime leads to a better theory in practice ( Is Space-Time Really Doomed? | Not Even Wrong ).

What remains valid about spacetime? From a practical standpoint, spacetime is an excellent effective theory. For any experiment not probing Planck-scale gravity, we can safely treat spacetime as fundamental. Even emergent-space proponents agree that the familiar continuum with locality and causality is a low-energy, large-scale approximation that works extremely well. It’s similar to how a fluid is not fundamental (it’s atoms), but you can still use continuum fluid dynamics to design an airplane. Likewise, we will keep using spacetime-based theories for most engineering and science. The big question is whether the approximation ever breaks down in observable ways. If spacetime is emergent from quantum microstructure, are there “leaks” or anomalies? Possibilities include: violations of Lorentz symmetry at ultra-high energies, a minimal measurable length, or emergent phenomena like holographic noise. Experiments have sought signs of discreteness or holography (e.g. the Fermilab Holometer looked for holographic jitter), but so far no conclusive deviation from continuum spacetime has been detected. This lack of direct evidence tempers claims of spacetime’s demise – it might be doomed in theory, but it’s been exceedingly robust in practice.

Moreover, not everyone agrees on the extent of spacetime’s doom. Some physicists think maybe space is emergent but time is fundamental (or vice versa). Debates rage whether time is an illusion – Julian Barbour famously argued that time is just change without a distinct flowing entity, whereas others like Lee Smolin argue time might be a more fundamental aspect of reality than space. Quantum gravity approaches differ: loop quantum gravity suggests spacetime is replaced by something discrete but still “there” in a sense (spin networks in lieu of a manifold), whereas in AdS/CFT one might say the fundamental description still has a time coordinate (in the boundary field theory) so time might survive even if space is emergent. There’s also the question of observer dependence: some say spacetime might be like an emergent “frame” that different observers or agents construct. Carlo Rovelli’s relational quantum mechanics is an example where properties (and perhaps spacetime itself) are viewed as relational – there’s no god’s-eye-view of spacetime, only interactions between systems ( Is Space-Time Really Doomed? | Not Even Wrong ). These nuances mean “spacetime is doomed” can mean different things: doomed as a fundamental ontological entity, or doomed as an invariant concept, etc. The exact nature of the replacement is unclear – is it purely mathematical (like a wavefunction in a high-dimensional Hilbert space)? Is it a network or graph? A spin foam? Or something entirely novel like a category-theoretic structure or a mental construct? We don’t yet know.

Crucially, the emergent spacetime idea itself is still being fleshed out and tested theoretically. For example, the holographic principle works beautifully in Anti-de Sitter space scenarios, but our universe is not AdS – it’s de Sitter (with positive cosmological constant) and has expansion. There is no agreed holographic dual for a cosmology like ours, which means the emergent space program has a big gap when it comes to describing a realistic universe with gravity and acceleration. Similarly, the amplituhedron so far applies to a specific toy model (N=4 supersymmetric Yang-Mills in flat space) (A Jewel at the Heart of Quantum Physics | Quanta Magazine). It’s a striking demonstration, but QCD (real-world particle physics) and gravity itself are not yet derived from a timeless geometry. Skeptics might say: “Show me emergent spacetime can predict a new number or explain a paradox that cannot be handled in spacetime terms, then I’ll be convinced.” So far, many emergent-space arguments are more like post hoc reinterpretations of known phenomena (e.g. entanglement=geometry) rather than predictive new laws. This could change, but it’s a reminder that we’re in the early days.

Finally, philosophical counterpoints exist to idealist interpretations. Physicalist philosophers will argue that invoking consciousness as fundamental is unnecessary and doesn’t obviously lead to testable predictions in physics. They’d point out that we can have emergent spacetime from quantum math alone, without needing “conscious agents.” The burden is on those models to produce a clear experimental discriminator (for instance, an idealist might predict some deviation in brain physics or a violation of quantum theory for truly isolated systems, etc., but none is agreed upon yet). Until then, mainstream science will stick to more parsimonious views (information is fine – since it relates to physics – but consciousness as an entity outside of spacetime is much harder to pin down scientifically).

In essence, the debates are lively and ongoing. Is spacetime emergent or fundamental? It remains one of the biggest unanswered questions at the foundations of physics. What’s clear is that leading researchers are increasingly entertaining the idea of emergent spacetime because of both theoretical and experimental pressures. Even if spacetime is not completely “doomed,” it may need to share the stage with deeper principles. The next few decades (as Arkani-Hamed predicts (The Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-Hamed)) could bring radical developments – possibly a new synthesis where quantum mechanics and spacetime emerge together from something novel. Until then, spacetime straddles an interesting status: our most reliable intuition about reality’s layout, yet possibly a mere epiphenomenon of a deeper order.

Post-Spacetime Theories at a Glance

To summarize the landscape of ideas beyond fundamental spacetime, the following table lists some key theoretical frameworks and their core claims:

Table: Post-Spacetime Theoretical Models – A summary of various approaches that treat spacetime as an emergent or secondary phenomenon, along with their core propositions. Each of these models challenges the classical idea of spacetime as the base-level reality, offering a different candidate for what lies “beneath” spacetime (be it quantum information, geometric constructs, or even consciousness).

Conclusion

The statement “spacetime is doomed” encapsulates a paradigm shift in progress. From quantum gravity research indicating that a smooth spacetime cannot be fundamental, to experiments showing nature’s nonlocal and observer-dependent character, to philosophical arguments that physical reality is an interface of deeper structures – all converge on the need to rethink the role of space and time in the foundational ontology. We stand at a juncture not unlike the early 20th century, when the comfortable certainties of Newtonian space and time gave way to relativity and quantum weirdness. Now the frontier asks us to go one step further: to envision a cosmos where space and time themselves are not the bedrock, but foam on the sea of a deeper reality.

Mainstream physics still treats spacetime as real – and indeed any new theory must explain why spacetime appears so real to us and works so well. In that sense, spacetime’s “doom” is not a demolition but a demotion: it will remain as an emergent layer, much as atoms remain useful concepts even though they are made of quarks and gluons. The debates today are rich with possibilities. Perhaps in the coming years, a clear winner will emerge – a theory that unites quantum mechanics and gravity and confirms that spacetime is built from X (whatever X may be). Or perhaps we will find spacetime’s reign extended by new insights that make it fundamental in a novel way (some fringe proposals even suggest time might be fundamental after all, or that quantum mechanics will give way instead). For now, the intellectual excitement is palpable. Physicists talk about learning to “think outside spacetime” to solve problems, and philosophers draw inspiration to question physicalism at the most basic level.

In exploring why spacetime might not be fundamental, we are probing the very limits of human understanding. It forces us to ask: What is reality, if not space and time? The tentative answers involve concepts almost as enigmatic – entanglement, information, computation, awareness. Yet, by pushing these boundaries, science inches closer to a unified description of nature. If spacetime is indeed an emergent construct, acknowledging that is not a defeat, but a profound insight. It would mean we have identified the next layer of the cosmic onion to peel away, revealing a new level of the structure of existence. As with every paradigm shift, the transition is fraught with uncertainty, debate, and the need for evidence. But if history is any guide, the truth has a way of asserting itself. And the next revolution – the one beyond spacetime – might redefine our understanding as dramatically as any revolution before.

Sources:

• Arkani-Hamed, N. et al., “The End of Space-Time?” (Messenger Lectures, Cornell University, 2010). Quoted in (Amplituhedron May Shape the Future of Physics | Discover Magazine).
• Van Raamsdonk, M. et al., Building up spacetime with quantum entanglement, Gen. Rel. Grav. 42:2323 (2010) ([1005.3035] Building up spacetime with quantum entanglement).
• Wolchover, N., “A Jewel at the Heart of Quantum Physics”, Quanta Magazine (2013) – on the amplituhedron (A Jewel at the Heart of Quantum Physics | Quanta Magazine) (A Jewel at the Heart of Quantum Physics | Quanta Magazine) (A Jewel at the Heart of Quantum Physics | Quanta Magazine).
• Garisto, D., “The Universe Is Not Locally Real”, Scientific American (Oct 6, 2022) – overview of Bell tests and 2022 Nobel (The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific American) (The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific American) (The Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific American).
• Hossenfelder, S., Backreaction blog discussions (2016–2022) – commentary on emergent spacetime ideas ( Is Space-Time Really Doomed? | Not Even Wrong ).
• Hoffman, D.D., “Spacetime is doomed: time is an artifact”, Timing & Time Perception 12:189 (2024) – discusses amplituhedra and conscious agents () ().
• Hoffman, D.D., Interview “The Case Against Reality” (Tim Ferriss Show, 2022) – on consciousness as fundamental (Professor Donald Hoffman — The Case Against Reality, Beyond Spacetime, Rethinking Death, Panpsychism, QBism, and More (#585) - The Blog of Author Tim Ferriss).
• Wheeler, J.A., “Information, Physics, Quantum” (Proc. 3rd Int. Symp. Found. Quantum Mech., 1989) – origin of “it from bit” quote (John Archibald Wheeler Postulates "It from Bit" : History of Information) (John Archibald Wheeler Postulates "It from Bit" : History of Information).
• Jafferis, D. et al., Traversable wormhole dynamics on a quantum processor, Nature (2022) – as reported by Quanta Magazine (Physicists Create a Wormhole Using a Quantum Computer | Quanta Magazine).
• Planck, M., Scientific Autobiography (1949) – source of Planck’s principle quote on scientific generations (Planck's principle - Wikipedia).

Appendix: AI Though Process

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Trying another angle

Searched for "spacetime is doomed" ArkaniChatGPT

I’m examining physicists' speculative ideas on spacetime's weakening, especially Arkani-Hamed's views on the amplituhedron and entanglement's implications.

I’m evaluating mainstream physics' acceptance of spacetime versus alternative theories like amplituhedron and consciousness-based models, considering their implications and challenges.

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Arkani-Hamed examines how small distances demand high energies, risking black holes, and raising questions about the breakdown of spacetime as a continuum.

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Arkani-Hamed's "space-time doomed" and quantum mechanics' limitations require new principles, suggesting space-time and quantum mechanics are emergent from a deeper theory.

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Woit notes that Arkani-Hamed's "spacetime is doomed" slogan is a vague motivation for amplitude research, sidestepping concrete connections.

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I'm piecing together quantum gravity's link to holography, gauging if this theory extends beyond 4D spacetime to higher dimensions.

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I’m thinking about quantum gravity, considering string theory, loop quantum gravity, and the holographic principle, and also exploring causality and geometric objects affecting scattering amplitudes.

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I noticed a potential out-of-reach article title, suggesting an academic journal with a time-related focus. The title hints at advanced concepts in spacetime and time, but accessing the full text might be challenging.

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Amplituhedron and decorated permutations bridge physics and philosophy, hinting at a Markovian dynamic beyond time.

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Amplituhedra's volumes encode scattering, facial symmetries hint at spacetime's precursors, emerging as a projection in newfound physics, resembling Donald's consciousness concepts.

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I’m examining Donald Hoffman's link to Arkani-Hamed's work and considering citations from [12] and [13]. Also, exploring authoritative sources on the holographic principle and emergent spacetime.

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I’m identifying key insights from Van Raamsdonk's essay, particularly the relationship between classically connected spacetimes and quantum entanglement.

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I’m gathering sources to support Van Raamsdonk's thesis, including the 2022 Nobel press release, and considering the influence of "Bell test experiments" on local realism.

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I’m looking into how physicists prove that the universe isn’t locally real. It’s fascinating to see their progress in understanding reality.

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I'm summarizing key points about quantum themes and ideals, including Bell inequalities and Donald Hoffman's idealism.

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I’m exploring various philosophical positions like Analytic Idealism, Rovelli's RQM, and Julian Barbour's time illusions. However, I’m mainly focusing on Donald Hoffman's Conscious Realism theory, published in journals such as Entropy.

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I'm gathering insights from a Reddit post, scholarly articles on consciousness by Neil Seth, and Tim Ferriss' blog, all discussing how spacetime is an interface illusion shaped by evolution.

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I'm considering Donald Hoffman's bold claim that consciousness is fundamental over spacetime. Reference to sci-am piece helps contextualize this idea.

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Examining historical dynamics, like Einstein's General Relativity adoption, and noting public figures' views on innovation.

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Investigating how quantum computing, entanglement, and emergent spacetime theories might link quantum tech, like quantum teleportation and encryption, to deeper realms beyond spacetime.

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Examining how physicists utilizing quantum computers may reveal insights into emergent spacetime.

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Quantum information opens doors, pondering space-time's origin in a wormhole experiment.

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I'm curious about how gravity might stem from quantum bits, and I'm exploring the association with wormhole emergence and quantum technology use.

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I'm mapping out views on spacetime, considering concepts like non-commutative geometry and string theory. Interesting to see the emphasis on spacetime potentially being an emergent phenomenon.

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I’m thinking about Sean Carroll's mainstream theoretical physics, especially his exploration of entanglement and quantum mechanics. This aligns with emergent gravity from a Many-worlds wavefunction perspective.

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Forum idea: space's emergence through gravity and Quantum Mechanics. Exploring formal references and direct Sean Carroll's blog.

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I'm mapping out an outline for a thorough analysis of the phrase "spacetime is doomed," referencing quantum gravity theories, scattering amplitudes, holographic principles, and distinct spacetime concepts.

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I'm thinking about quantization in physics, noting if gravity involves discrete spacetime chunks at Planck scale, addressing spacetime continuity and emergent properties, and the potential use of conceptual images for further clarification.

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The article might explore the amplituhedron's potential, eliminating the need for spacetime in theoretical physics.

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Considering the statement that space-time and probabilities derive from the amplituhedron's geometry, challenging conventional notions of these constructs.

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I'm examining the amplituhedron to challenge the space-time construct, suggesting its fundamentals might be illusory.

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I’m synthesizing perspectives on spacetime and entanglement, integrating quantum gravity challenges, holography, and philosophical models, while also considering the implications of a post-spacetime reality.

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Images in Quanta are tricky to capture, often loaded differently. Searching specifically for "amplituhedron image Andy Gilmore" might be a simpler method.

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I'm thinking Discover magazine might have the exact image link for "amplitudehedron".

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Arkani-Hamed's direct quote captures space-time's eventual fate, perfectly aligning with the image link. This confirms the concept's origin and clarifies its significance.

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I’m looking at scientific illustrations like amplitudehedron and holography, considering their relevance and citing them properly in the text.

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I'm gathering images for entangled particles, quantum puzzles, and Bell tests, including a Bell test experimental setup or a conceptual diagram. This leads me to a specific image resonating well.

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Wheeler's quote highlights the concept that physical reality originates from immaterial sources and is shaped by questions and responses.

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OK, let me see. Wheeler's idea ties every physical entity to binary choices, including spacetime. This insight drives the next steps.

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OK, I’m pulling together the final answer, using Wheeler's words as a reference point.

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Citations

pswscience.orgThe Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-HamedTo explain the first cloud, Arkani-Hamed presented a thought experiment. To see what exactly is going on at arbitrarily small distances, we must use high energies. In a world without gravity, there is, in principle, no limit to scaling the size of the detector to see what is going on at increasingly small distances. But we live with gravity, and where there is too much mass, we get a black hole that traps light – meaning that if we build too big a detector, we will create a black hole that will prevent us from seeing what happens at the smallest distances. Thus, gravity limits our ability to measure spacetime, which means our current understanding of spacetime is merely approximate and notpswscience.orgThe Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-Hamedenergies. In a world without gravity, there is, in principle, no limit to scaling the size of the detector to see what is going on at increasingly small distances. But we live with gravity, and where there is too much mass, we get a black hole that traps light – meaning that if we build too big a detector, we will create a black hole that will prevent us from seeing what happens at the smallest distances. Thus, gravity limits our ability to measure spacetime, which means our current understanding of spacetime is merely approximate and not fully accurate.pswscience.orgThe Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-Hameddistances. But we live with gravity, and where there is too much mass, we get a black hole that traps light – meaning that if we build too big a detector, we will create a black hole that will prevent us from seeing what happens at the smallest distances. Thus, gravity limits our ability to measure spacetime, which means our current understanding of spacetime is merely approximate and not fully accurate.pswscience.orgThe Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-Hamedwill create a black hole that will prevent us from seeing what happens at the smallest distances. Thus, gravity limits our ability to measure spacetime, which means our current understanding of spacetime is merely approximate and not fully accurate.discovermagazine.comAmplituhedron May Shape the Future of Physics | Discover Magazineclue that something’s amiss with current assumptions about the universe.)pswscience.orgThe Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-HamedSince spacetime and quantum mechanics are limited and approximately, Arkani- Hamed said they cannot be fully accurate. To be fully accurate, we must rethink our most basic understandings of physics, as there are no measurements of any sort in the interior of space and time that can belong as precise properties of the world.pswscience.orgThe Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-HamedArkani-Hamed’s believes both spacetime and quantum mechanics will emerge together from new principles about the fundamental of physics. To find these new principles, we must consider how to approach the problem. As examples, Arkani- Hamed described how 20th century physicists re-thought determinism, and how Richard Feynman’s intimidating method of doing physics reduced to simple formulas. As scientists did in those instances, we must rethink the fundamentals of physics to find the simple truths.arxiv.org[1005.3035] Building up spacetime with quantum entanglement> Abstract:In this essay, we argue that the emergence of classically connected spacetimes is intimately related to the quantum entanglement of degrees of freedom in a non-perturbative description of quantum gravity. Disentangling the degrees of freedom associated with two regions of spacetime results in these regions pulling apart and pinching off from each other in a way that can be quantified by standard measures of entanglement.annualreviews.orgSpacetime from Entanglement | Annual ReviewsThis is an idiosyncratic colloquium-style review of the idea that spacetime and gravity can emerge from entanglement. Drawing inspiration from the conjectured duality between quantum gravity in anti de Sitter space and certain conformal field theories, we argue that tensor networks can be used to define a discrete geometry that encodes entanglement geometrically. With the additional assumption that a continuum limit can be taken, the resulting geometry necessarily obeys Einstein's equations. The discussion takes the point of view that the emergence of spacetime and gravity is a mysterious phenomenon of quantum many-body physics that we would like to understand. We also briefly discuss possible experimentsquantamagazine.orgA Jewel at the Heart of Quantum Physics | Quanta Magazinematch at L200 removes locality and unitarity from its starting assumptions. The amplituhedron is not built out of space-time and probabilities; these properties merely arise as consequences of the jewel’s geometry. The usual picture of space and time, and particles moving around in them, is a construct.quantamagazine.orgA Jewel at the Heart of Quantum Physics | Quanta Magazineremoves locality and unitarity from its starting assumptions. The amplituhedron is not built out of space-time and probabilities; these properties merely arise as consequences of the jewel’s geometry. The usual picture of space and time, and particles moving around in them, is a construct.pdfs.semanticscholar.orgMany high-energy theoretical physicists have moved on (see, e.g., Bain, 2020). In the last decade they have found new structures deeper than spacetime and quantum theory. Amplituhedra, for instance, are geometric structures that are logically prior to spacetime and Hilbert spaces. Their volumes are scattering amplitudes. Their faces encode locality and unitarity, key properties of spacetime and quantum theory. Amplituhedra reveal a simplicity and symmetry in scatteringquantamagazine.orgA Jewel at the Heart of Quantum Physics | Quanta MagazineBeyond making calculations easier or possibly leading the way to quantum gravity, the discovery of the amplituhedron could cause an even more profound shift, Arkani-Hamed said. That is, giving up space and time as fundamental constituents of nature and figuring out how the Big Bang and cosmological evolution of the universe arose out of pure geometry.scientificamerican.comThe Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific AmericanOne of the more unsettling discoveries in the past half a century is that the universe is not locally real. In this context, “real” means that objects have definite properties independent of observation—an apple can be red even when no one is looking. “Local” means that objects can be influenced only by their surroundings and that any influence cannot travel faster than light. Investigations at the frontiers of 4 have found that these things cannot both be true. Instead the evidence shows that objects are not influenced solely by their surroundings, and they may also lack definite properties prior to measurement.scientificamerican.comThe Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific AmericanBlame for this achievement has been laid squarely on the shoulders of three physicists: John Clauser, Alain Aspect and Anton Zeilinger. They equally split the 2022 Nobel Prize in Physics “for experiments with entangled photons, establishing the violation of Bell inequalities and pioneering quantum information science.” (“Bell inequalities” refers to the trailblazing work of physicist John Stewart Bell of Northern Ireland, who laid the foundations for the 2022 Physics Nobel in the early 1960s.) Colleagues agreed that the trio had it coming, deserving this reckoning for overthrowing reality as we know it. “Itquantamagazine.orgPhysicists Create a Wormhole Using a Quantum Computer | Quanta MagazineThe unprecedented experiment explores the possibility that space-time somehow emerges from quantum information, even as the work’s interpretation remains disputed.quantamagazine.orgPhysicists Create a Wormhole Using a Quantum Computer | Quanta Magazine“I think it is true that gravity in our universe is emergent from some quantum [bits] in the same way that this little baby one-dimensional wormhole is emergent” from the Sycamore chip, Jafferis said. “Of course we don’t know that for sure. We’re trying to understand it.”historyofinformation.comJohn Archibald Wheeler Postulates "It from Bit" : History of Informationfrom four conclusions: (1) The world cannot be a giant machine, ruled by any preestablished continuum physical law. (2) There is no such thing at the microscopic level as space or time or spacetime continuum. (3) The familiar probability function or functional, and wave equation or functional wave equation, of standard quantum theory provide mere continuum idealizations and by reason of this circumstance conceal the information-theoretic source from which they derive. (4) No element in the description of physics shows itself as closer to primordial than the elementary quantum phenomenon, that is, the elementary device-intermediated act of posing a yes-no physical question andhistoryofinformation.comJohn Archibald Wheeler Postulates "It from Bit" : History of Informationthe most effective one that has survived this winnowing: It from bit. Otherwise put, every it — every particle, every field of force, even the spacetime continuum itself — derives its function, its meaning, its very existence entirely — even if in some contexts indirectly — from the apparatus elicited answers to yes or no questions, binary choices [52], bits.historyofinformation.comJohn Archibald Wheeler Postulates "It from Bit" : History of Informationanswers to yes or no questions, binary choices [52], bits.math.columbia.eduIs Space-Time Really Doomed? | Not Even WrongApril 3, 2022 at 5:40 pmhistoryofinformation.comJohn Archibald Wheeler Postulates "It from Bit" : History of Information"It from bit symbolizes the idea that every item of the physical world has at bottom — at a very deep bottom, in most instances — an immaterial source and explanation; that what we call reality arises in the last analysis from the posing of yes-no questions and the registering of equipment-evoked responses; in short, that all things physical are information-theoretic in origin and this ishistoryofinformation.comJohn Archibald Wheeler Postulates "It from Bit" : History of Information"It from bit symbolizes the idea that every item of the physical world has at bottom — at a very deep bottom, in most instances — an immaterial source and explanation; that what we call reality arises in the last analysis from the posing of yes-no questions and the registering of equipment-evoked responses; in short, that all things physical are information-theoretic in origin and this is a participatory universe. Three examples may illustrate the theme of it fromtim.blogProfessor Donald Hoffman — The Case Against Reality, Beyond Spacetime, Rethinking Death, Panpsychism, QBism, and More (#585) - The Blog of Author Tim Ferriss“Physics is not fundamental. Spacetime is not fundamental. Consciousness is. What we call physical objects are merely the ways that we play with our interface to open new portals into the realm of conscious agents.” — Donald Hoffmanpdfs.semanticscholar.orgthus are beyond the unitary formalism of quantum theory. Spacetime is a projection of a deeper reality. In that projection, an arrow of time can arise as an artifact. Markov chains have a notion of sequence, but needpdfs.semanticscholar.orgSo proper time and entropic time are doomed because spacetime is doomed. Beyond spacetime lurk amplituhedra and decorated permutations. Beyond decorated permutations may be a Markovian dynamic outside of time, on a probability space perhaps experienced as the now.pdfs.semanticscholar.orgall Markovian dynamics that are entropy-nonincreasing are also not unitary, andpdfs.semanticscholar.orgdistinguish moves left and right (Arkani-Hamed et al., 2016). But permutations of what, andpdfs.semanticscholar.orgIt turns out that decorated permutations classify dynamical systems called Markov chains, by compactly describing their ‘communicating classes’ (Hoffman et al., 2023). In the Twitterverse, for instance, each user in a communicating class eventually sees every tweet of every user in that class. It’s easy to construct stationary Markov chains whose entropy does not increase.scientificamerican.comThe Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific AmericanThis is, of course, deeply contrary to our everyday experiences. As Albert Einstein once bemoaned to a friend, “Do you really believe the moon is not there when you are not looking at it?” To adapt a phrase from author Douglas Adams, the demise of local realism has made a lot of people very angry and has been widely regarded as a bad move.en.wikipedia.orgPlanck's principle - WikipediaThis was formulated by Max Planck:[ 1 ]en.wikipedia.orgPlanck's principle - Wikipedia> — Max Planck, Scientific autobiography, 1950, p. 33, 97scientificamerican.comThe Universe Is Not Locally Real, and the Physics Nobel Prize Winners Proved It | Scientific AmericanThe journey from fringe to favor was a long one. From about 1940 until as late as 1990, studies of so-called quantum foundations were often treated as philosophy at best and crackpottery at worst. Many scientific journals refused to publish papers on the topic, and academic positions indulging such investigations were nearly impossible to come by. In 1985 Popescu’s adviser warned him against a Ph.D. in the subject. “He said, ‘Look, if you do that, youmath.columbia.eduIs Space-Time Really Doomed? | Not Even WrongDarran, That was a reference not to Arkani-Hamed, but to the well-publicized and well- funded “It from Qubit” stuff.quantamagazine.orgA Jewel at the Heart of Quantum Physics | Quanta Magazinecomputing the volume of the corresponding jewel-like “amplituhedron,” which yields an equivalent one-term expression.math.columbia.eduIs Space-Time Really Doomed? | Not Even WrongThese days Arkani-Hamed typically uses the “spacetime is doomed”argument as motivation for his work on reformulating amplitudes calculations, but I don’t think the relation is much more than vaguely motivational.math.columbia.eduIs Space-Time Really Doomed? | Not Even WrongEssentially because spacetime degrees of freedom would be local ones if they retain their character from GR. If there doesn’t seem to be local observables due how measurements work in a realistic cosmological setting it is hard to see how the proper quantum theory would involve spacetime in its conventional form.quantamagazine.orgA Jewel at the Heart of Quantum Physics | Quanta MagazinePhysicists must also prove that the new geometric formulation applies to the exact particles that are known to exist in the universe, rather than to the idealized quantum field theory they used to develop it, called maximally supersymmetric Yang-Mills theory. This model, which includes a “superpartner” particle for every known particle and treats space-time as flat, “just happens to be the simplest test case for these new tools,” Bourjaily said. “The way to generalize these new tools to [other] theories is understood.”pswscience.orgThe Doom of Spacetime - Why It Must Dissolve Into More Fundamental Structures - Nima Arkani-HamedIn current research, Arkani-Hamed says physics and mathematics are working on the same questions with radically different approaches. He is optimistic those diverse approaches will bring about radical redevelopment and maybe in 20-50 years bring about a new grand unified theory.pdfs.semanticscholar.orgthis new physics, spacetime and quantum theory emerge, together, as a projectionquantamagazine.orgA Jewel at the Heart of Quantum Physics | Quanta Magazinetheory and quantum field theory, indicating that the former (which includes gravity) is mathematically equivalent to the latter (w