Istanbul Physicist Shows Fleeting Quantum States Alter Brain Signals

Sabine Hossenfelder

Transient entangled superpositions can leave persistent thermodynamic imprints on neural activity without requiring long-lived coherence or exotic gravitational collapse mechanisms.

AI-assisted summary of Human Thought Can Depend on Quantum Superpositions, Physicists Shows — original source. Check the original for full context.

Source published: 2026-10-04

Key ideas

A new preprint from a physicist in Istanbul proposes that quantum superpositions can influence human thought without requiring long-lived coherence in the warm, wet environment of the brain. (2:33)
Using quantum thermodynamics, the model shows that an initial entangled superposition leaves permanent residual correlations in subsequent physical states even after rapid decoherence. (2:33)
Unlike Penrose and Hameroff's Orch-OR theory, the proposal requires no exotic physics or gravitational collapse and is concretely testable in cultured neural tissue. (4:40)
Sabine Hossenfelder awards the paper a favorable 6/10 on her 'bullshit meter', noting its physics is sound while the primary open question remains its neurobiological relevance. (4:40)

Detailed notes

## Background Published on YouTube on October 4, 2026, by physicist Sabine Hossenfelder, this video investigates whether quantum superpositions can play a role in human thought. The channel description notes that while most literature on quantum brain mechanics is nonsense, a new paper by a physicist in Istanbul proposes that quantum effects do not need to last long to leave a permanent mark, presenting a testable hypothesis that avoids exotic physics.

## TL;DR Hossenfelder examines a new preprint proposing that transient quantum superpositions can directly shape human brain dynamics without requiring long-lived coherence. Unlike past models from Penrose and Hameroff that relied on speculative gravitational collapse, this framework uses quantum thermodynamics to demonstrate that brief entangled states leave persistent physical correlations even after rapid decoherence. Candidate biological substrates include hydrogen bonds, microtubules, and phosphate groups, with the mechanism being testable in cultured neural tissue. While its neurobiological relevance remains unproven, Hossenfelder awards the mathematically sound proposal a favorable 6 out of 10 on her bullshit meter.

## Atmosphere & style The presentation carries Sabine's trademark blend of dry wit, biting skepticism, and disciplined scientific clarity. She grounds an often sensationalized topic with playful reality checks—comparing the brain's basic quantum nature to a block of cheese and joking about consciousness losing its glamour without spacetime curvature. The delivery feels refreshingly level-headed and intellectually rigorous, transforming what is typically fringe speculation into a grounded assessment of thermodynamics and neurobiology.

## Bulletin - [02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) A new preprint from a physicist in Istanbul proposes that quantum superpositions can influence human thought without requiring long-lived coherence in the warm, wet environment of the brain. - [02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) Using quantum thermodynamics, the model shows that an initial entangled superposition leaves permanent residual correlations in subsequent physical states even after rapid decoherence. - [04:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=280s) Unlike Penrose and Hameroff's Orch-OR theory, the proposal requires no exotic physics or gravitational collapse and is concretely testable in cultured neural tissue. - [04:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=280s) Sabine Hossenfelder awards the paper a favorable 6/10 on her 'bullshit meter', noting its physics is sound while the primary open question remains its neurobiological relevance.

## Key takeaways - [00:00](https://www.youtube.com/watch?v=ehba2U4oNJo&t=0s) Whether quantum mechanics plays an active role in human thought is central to understanding consciousness and the theoretical limits of classical artificial intelligence. - [00:00](https://www.youtube.com/watch?v=ehba2U4oNJo&t=0s) Everything in nature relies trivially on quantum physics to exist at the atomic scale; the critical question is whether non-trivial phenomena like quantum superposition shape brain dynamics. - [01:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=100s) The hot, wet, and noisy environment of biological tissue causes rapid decoherence in femtoseconds, presenting the primary obstacle for quantum brain theories. - [01:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=100s) Roger Penrose and Stuart Hameroff's Orch-OR theory relies on gravitationally induced collapse in microtubules, an idea widely dismissed by mainstream physicists. - [01:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=100s) Matthew Fisher's hypothesis suggests long-duration coherence in nuclear spins of phosphate molecules, but has similarly struggled to gain mainstream acceptance. - [02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) Standard assumptions hold that when a quantum superposition decoheres, it collapses into a classical state and completely erases any trace of the superposition. - [02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) The new thermodynamic model demonstrates that transient entangled superpositions leave measurable physical imprints that alter downstream system states. - [02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) Candidate biological substrates that could host these brief quantum states include delocalized protons in hydrogen bonds, microtubules, and phosphate groups. - [02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) The proposed mechanism requires no new physics, spacetime curvature alterations, or gravitational collapse mechanisms. - [04:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=280s) The hypothesis is experimentally testable in laboratory settings using cultured neural tissue to detect downstream quantum correlation signatures. - [04:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=280s) If confirmed, the mechanism would imply that the human brain relies on non-classical physics that classical computational architectures cannot easily simulate. - [04:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=280s) The main remaining uncertainty is whether these microscopic quantum fingerprints have any meaningful functional role in neural information processing.

## Detailed walkthrough ### [00:00](https://www.youtube.com/watch?v=ehba2U4oNJo&t=0s) The Question of Quantum Mechanics in the Brain

Whether quantum mechanics plays a role in the human brain is one of the most tantalizing questions in science. If the brain actively exploits quantum physics, it might help explain quintessential human experiences—such as the conscious sensation of choosing between alternatives and turning mere possibility into reality. It would also fundamentally reshape our understanding of artificial intelligence, placing clear boundaries on what conventional computational architectures can and cannot reproduce. Yet, the field has long been plagued by low-quality research, with most published work on the topic bordering on nonsense.

The main conceptual hurdle in addressing this question is that the answer is trivially "yes." Everything in the physical universe relies on quantum phenomena at the fundamental scale; without quantum physics, atoms would collapse and molecules would not exist. By that trivial standard, quantum mechanics plays an equally vital role in a block of cheese. The genuinely interesting question is whether distinctly quantum effects—such as quantum superpositions, where a physical system exists in two states at once—can directly shape human thought, allowing a person to hold multiple states in superposition before a conscious act of will collapses them into a choice.

```mermaid flowchart TD accTitle: Classical View vs Transient Quantum Imprint accDescr: Diagram contrasting the standard assumption of fragile coherence collapse with the new model where transient entanglement leaves persistent correlations.

subgraph Traditional["Traditional View (Fragile Coherence)"] A["Quantum Superposition"] -->|"Decoheres rapidly"| B["Single Classical State"] B --> C["No lasting trace of superposition"] end

subgraph NewModel["New Thermodynamic Model"] D["Transient Entangled Superposition"] -->|"Decoherence occurs"| E["Persistent Residual Correlations"] E -->|"Physical imprint"| F["Altered Subsequent Neural Activity"] end ```

[01:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=100s) Past Speculations and Why Physicists Rejected Them

Prior attempts to link quantum mechanics to consciousness have generally relied on extraordinary or unverified physics. The most famous framework, proposed by Roger Penrose and Stuart Hameroff, suggests that quantum wavefunctions exist within microtubules—microscopic structural components inside neurons—and that their collapse generates discrete moments of consciousness. Crucially, Penrose and Hameroff tied this wavefunction collapse to the fundamental structure of spacetime through gravitationally induced objective collapse, an idea that virtually every mainstream physicist considers nonsense.

Another notable proposal came from physicist Matthew Fisher, who posited that nuclear spins within phosphate molecules could sustain long-lived quantum coherence, eventually steering neurotransmitter release and neuronal firing. However, Fisher's hypothesis has similarly failed to gain traction within the scientific community, alongside countless fringe theories from non-physicists. The primary stumbling block has always been the hot, wet, and noisy environment of the brain, which causes quantum coherence to decohere almost instantaneously.

- **Penrose–Hameroff Orch-OR:** Relies on quantum superpositions inside neural microtubules collapsing via gravitational spacetime effects. - **Matthew Fisher's Hypothesis:** Suggests shielded nuclear spins in Posner molecules maintain long-duration coherence to regulate neurotransmitter release. - **The Decoherence Problem:** Thermal fluctuations in biological tissue traditionally wipe out quantum superpositions in femtoseconds, long before neurobiological signaling occurs.

[02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) The New Proposal: Lasting Traces Without Long Coherence

A new preprint from a physicist based in Istanbul departs from previous attempts by abandoning the requirement for long-lived quantum coherence. In standard discussions of brain function, it is assumed that if a superposition forms—such as two neurons firing simultaneously or two distinct thoughts coexisting—its rapid collapse leaves behind only a single classical state (like suddenly forgetting why you walked into the kitchen), erasing any evidence that a superposition ever occurred.

Drawing on formal principles from quantum thermodynamics, the author demonstrates that if a system originates in an entangled superposition, the ensuing physical state retains correlations that would not exist if the superposition had never occurred in the first place. Even when quantum coherence is fleeting, the brief existence of the quantum state leaves an indelible physical mark on the system's subsequent dynamics. As the author summarizes:

> "Functional relevance need not require the long-time preservation of fragile quantum coherence."

The paper identifies several candidate biological substrates where such transient effects could operate, including hydrogen bonds where protons delocalize across multiple positions, neural microtubules, and phosphate groups. Unlike the Penrose–Hameroff model, this mechanism requires no exotic new physics, spacetime curvature effects, or spontaneous gravitational collapse mechanisms—a fact that Sabine jokingly notes is "slightly disappointing" because consciousness felt far more glamorous when it depended on the fabric of spacetime.

[04:40](https://www.youtube.com/watch?v=ehba2U4oNJo&t=280s) Testability and the Bullshit Meter Verdict

Although the author currently presents no direct experimental evidence proving these mechanisms operate in living tissue, the hypothesis has the rare virtue of being testable in a laboratory setting using cultured neural tissue. Experimentalists can probe whether genuine quantum correlations leave measurable traces in neural activity downstream. If validated, it would imply that the brain operates on non-classical physics that classical computers cannot easily simulate.

Sabine awards the paper a score of 6 out of 10 on her "bullshit meter"—a relatively favorable score given the history of the field. The physics grounding the paper is sound, and the core premise that a microscopic quantum effect can leave a macroscopic biological fingerprint is entirely viable. The unresolved question is not physical but neurobiological: whether these microscopic fingerprints actually serve any meaningful purpose in how the brain processes information. Nonetheless, Sabine views this paper as a rare, credible step toward making quantum biology in the brain scientifically respectable, adding that if it proves true, she looks forward to blaming quantum mechanics for all of her bad decisions.

[06:00](https://www.youtube.com/watch?v=ehba2U4oNJo&t=360s) Precision Engineering: Henson Shaving

The video concludes with a discussion of the engineering principles behind everyday tools, specifically the safety razors produced by the sponsor, Henson Shaving. The team behind Henson brings a background in aerospace engineering, having manufactured precision components for high-stakes projects including the International Space Station (ISS) and the ExoMars rover.

Henson applies those tight manufacturing standards to shaving technology to solve common causes of razor burn and cuts: - **Aerospace-Grade Tolerances:** Razor components are machined from solid metal rather than molded plastic, holding tolerances down to a hundredth of a millimeter (0.01 mm). - **Blade Exposure Control:** The razor secures the blade at an exact angle and minimizes blade chatter, cutting facial hair flush against the skin without grabbing or slicing tissue. - **Audience Promotion:** Viewers purchasing a Henson razor with Sabine's promotional link or code receive a pack of 100 free blades.

## Notable quotes > [02:33](https://www.youtube.com/watch?v=ehba2U4oNJo&t=153s) Functional relevance need not require the long-time preservation of fragile quantum coherence.

## Mentioned ExoMars rover, Henson Shaving, International Space Station, Matthew Fisher, Posner molecules, Roger Penrose, Sabine Hossenfelder, Stuart Hameroff

## Video description Upgrade Your Shaving Experience With Henson (100 Free Blades): https://hensonshaving.com/sabine

Nearly everything published about quantum physics in the brain is nonsense. This time a physicist in Istanbul has come up with something different, and the key move is that quantum effects don't need to last long to leave a permanent mark. No exotic new physics required, and there's a concrete way to test it. Let's take a look.

Paper: https://doi.org/10.48550/arXiv.2604.04069

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[Source](https://www.youtube.com/watch?v=ehba2U4oNJo)

中文简报

伊斯坦布尔物理学家表明短暂量子态可改变大脑信号瞬态纠缠叠加态无需长寿命相干性或奇异引力坍缩机制，即可在神经活动中留下持久的热力学印记。 Hossenfelder 分析了一篇新预印本论文，该论文提出瞬态量子叠加无需长寿命相干性即可直接影响人类大脑动力学。与 Penrose 和 Hameroff 以往依赖推测性引力坍缩的模型不同，该框架利用量子热力学证明，短暂纠缠态即便在快速退相干后也能留下持久的物理关联。候选生物底物包括氢键、微管和磷酸基团，且该机制可在培养的神经组织中进行检验。尽管其神经生物学相关性尚未得到证实，Hossenfelder 仍认为这一在数学上严谨的假说值得肯定，在其“废话计量器”（bullshit meter）上给出了 6/10 的积极评分。来自伊斯坦布尔一位物理学家的新预印本提出，在大脑温暖、潮湿的环境中，量子叠加无需长寿命相干性即可影响人类思维。 (2:33) 该模型利用量子热力学证明，即使在快速退相干之后，最初的纠缠叠加态仍会在随后的物理状态中留下永久的残留关联。 (2:33) 与 Penrose 和 Hameroff 的 Orch-OR 理论不同，该假说不需要奇异物理学或引力坍缩，且可在培养的神经组织中进行具体检验。 (4:40) Sabine Hossenfelder 在其“废话计量器”上为该论文打出了较为正面的 6/10 分，指出其物理学基础是可靠的，而主要的未决问题仍是其神经生物学相关性。 (4:40)

Reading summary

A new theoretical proposal suggests human cognition could be influenced by transient quantum superpositions that leave lasting physical traces, bypassing the traditional objection that the brain's noisy environment destroys quantum effects too quickly to matter. The Challenge of Brain Decoherence (0:00) While all matter fundamentally relies on quantum physics to prevent atomic collapse, claims that distinct quantum phenomena shape consciousness have long faced skepticism from mainstream physicists. Prominent frameworks, such as Roger Penrose and Stuart Hameroff's Orch-OR theory involving microtubules and gravitational collapse, or Matthew Fisher's hypothesis on nuclear spins in phosphate molecules, require speculative mechanisms to explain how fragile states could survive in warm biological environments. In standard neurobiology, the warm, wet, and noisy conditions of brain tissue trigger rapid decoherence on femtosecond timescales. Conventional views therefore assume that any short-lived superposition decoheres immediately into a classical state, leaving behind no lasting physical evidence of its quantum origin. Lasting Traces Through Quantum Thermodynamics (2:33) A preprint by an Istanbul-based physicist introduces an alternative model that abandons the requirement for sustained quantum coherence. Grounded in quantum thermodynamics, the paper demonstrates that when a system originates in an entangled superposition, its rapid decoherence still produces residual correlations that would not emerge from purely classical states. Under this model, functional relevance does not depend on preserving fragile quantum states over biological timescales. Potential biological substrates capable of hosting these transient states include delocalized protons within hydrogen bonds, neural microtubules, and phosphate groups, none of which require exotic gravitational collapse mechanisms or speculative modifications to physics. Laboratory Testability and Current Limits (4:40) Unlike many previous hypotheses linking quantum mechanics to the mind, this framework can be tested empirically using cultured neural tissue to determine whether quantum correlations leave measurable fingerprints on downstream neural signaling. If confirmed, the mechanism would imply that the brain relies on non-classical physics that classical computational architectures cannot easily emulate. Reviewing the proposal, Sabine Hossenfelder assesses its underlying physics as sound, giving it a 6 out of 10 on her assessment scale. However, the proposal currently lacks direct experimental verification, leaving open the primary biological question of whether these microscopic physical traces carry functional relevance for actual cognitive information processing. The hypothesis offers a physically grounded pathway for quantum effects in biology without relying on unverified physics, but its validity rests on future experimental tests demonstrating whether the brain functionally exploits these thermodynamic traces.

Source quotes

[2:33] Functional relevance need not require the long-time preservation of fragile quantum coherence.

Original transcript

[0:00] What is the role of quantum physics in the human brain? We don’t have a good answer to this. It’s [0:06] a big question because if it turned out that the human brain actually used quantum physics, [0:13] then maybe that could explain some of our experiences, [0:16] like the feeling that a decision we make turns a possibility into reality. [0:22] It would also give us a new perspective on what artificial intelligence can and can’t achieve. [0:28] Most of what gets published on quantum physics on the brain is nonsense. But today I have [0:34] a new paper that is both more modest and more interesting than anything I’ve previously seen on [0:40] the topic. A physicist argues, quite convincingly, that fleeting quantum effects can influence neural [0:47] activity much longer than we thought, just by standard physics. Let’s have a look. [0:52] The major problem with the question of whether quantum physics plays a role in the human brain is [0:58] not that we can’t answer it. The problem is that the answer is trivially yes. Because everything [1:03] has quantum properties if you look closely enough. Without quantum effects, atoms wouldn’t exist, [1:10] so of course quantum physics plays a role in the human brain! By the same standard, [1:15] quantum physics also plays an essential role in cheese. I await the conferences. [1:21] The more meaningful question is therefore whether quantum-typical effects like being in two states [1:27] at the same time can affect thought. Can you literally have two thoughts at the same time? [1:35] And can the power of your will turn one of those thoughts into a decision? [1:40] The most famous attempt to connect quantum physics to human thought comes from Roger Penrose [1:46] and Stuart Hameroff. They proposed that these quantum processes happen inside microtubules, [1:53] that are tiny structures in neurons, and that the collapse of their wavefunction produces moments [1:59] of consciousness. Their proposal connects this collapse to the structure of spacetime [2:05] and every physicist I’ve ever talked to about this thinks it’s nonsense. [2:09] The physicist Matthew Fisher has proposed that nuclear spins in certain molecules could have [2:15] long-lived quantum states which could eventually influence the release of neurotransmitters and [2:22] the firing of neurons. I don’t know anyone who believes this either. There are also a [2:27] lot of theories about quantum in the brain from non-physicists which I don’t even want to mention [2:33] The new proposal now comes from a physicist in Istanbul, [2:37] and he makes a very interesting point. He says that a quantum state doesn’t have [2:42] to keep its quantum properties for very long to have a lasting effect. [2:48] We usually assume that if we have some quantum superposition in the brain, [2:53] one of, say, two neurons firing at once or, more ambitiously, two thoughts at once. Then [3:01] this superposition will at some point collapse and leave only one state. One neuron that fires, [3:08] one thought, one moment in which your memory of why you went into the kitchen evaporates. [3:13] The author of the paper now says, actually, this might not be the case. [3:19] Because if the superposition existed at some point, even if only briefly, [3:24] then what happens at a later time might be different than if the superposition never existed. [3:31] He takes this insight from a research area called quantum thermodynamics, [3:35] so he does have a theoretical and mathematical backing. With that, he shows that if you start [3:41] with a particular type of superposition, an entangled state, then you are later left with [3:47] correlations that would not be there had it not been for the quantum effects. The quantum [3:52] effects leave a physical trace that affects what happens next. As he writes, “functional [3:59] relevance need not require the long-time preservation of fragile quantum coherence.” [4:04] He points to several places where this could happen. One is hydrogen bonds, where protons [4:11] can become delocalised between different positions. But he also looks at microtubules [4:18] and these phosphate groups that I mentioned earlier. And in both cases he says, yes, [4:23] actually these might leave an imprint on thoughts. And you don’t need any gravitationally induced [4:30] collapse or other fancy new physics for it. Which to be honest is slightly disappointing. [4:35] Consciousness was much more glamorous when it required the structure of spacetime. [4:40] The author has no experimental evidence that this actually happens. But he has a concrete [4:47] proposal for how to test this, with neural tissue in the laboratory. Basically he says, [4:53] just look at whether quantum correlations leave an imprint in the neurons later on. If he is right, [5:01] this could indeed mean that the human brain relies on quantum effects that a conventional computer [5:08] does not readily reproduce. This, needless to say, would be a very big finding. [5:14] What are we to make of this? I give this a 6 out of 10 on the bullshit meter. Compared with earlier [5:20] quantum-brain proposals, this one requires much less exotic physics. The core idea seems perfectly [5:27] reasonable to me: a tiny quantum effect can leave a big fingerprint in the brain. But it remains [5:33] unclear whether those fingerprints actually matter in the human brain to process information. [5:39] That isn’t a question I would pose to a physicist though, so I don’t want to blame [5:43] the author too much. I have a good feeling about this paper, I think this might be the point when [5:49] quantum physics in the brain finally began making sense. If this turns out to be right, [5:55] I look forward to blaming quantum mechanics for every bad decision I have ever made. [6:00] I find it fascinating how much research goes into everyday objects like the razors from today's [6:07] sponsor, Henson. This might come as somewhat of a surprise to you, but Henson's team have [6:13] a background in aero space engineering. They've built parts for the ISS and the ExoMars rover. [6:20] They use the same precision to design their razor. They figured out at exactly which angle [6:26] the blades need to be positioned so as to cut off hairs perfectly and not cut your skin. The pieces [6:32] that hold the blades are not plastic, but cut out from metal to a precision of a hundredth of [6:38] a millimeter. I prefer my husband cleanly shaven out without cuts, and Henson's is by far the best [6:45] razor I've seen at work. Also works for women. And of course, I have a special offer. If you buy [6:51] a Henson razor through my link or use my code, you'll get 100 blades for free along with it. [6:59] You've never shaved that scientifically. Thanks for watching. See you tomorrow.