Faster Than c? Entanglement, Non-Signaling Correlations, ER = EPR, and the Question of Retrocausality

© Courtney Hunt, MD, 2026

Abstract

Quantum mechanics permits correlations between entangled systems that appear to transcend classical notions of space and time. These correlations do not allow faster-than-light signaling, energy transfer, or message transmission, yet they challenge the assumption that causal structure must be local and strictly forward-propagating at or below the speed of light. Drawing on interaction-free measurement, time-symmetric interpretations of quantum mechanics, geometric approaches to spacetime, and the ER = EPR correspondence, this essay explores whether quantum correlations reflect global constraints across spacetime rather than signal-based causation. Reflections by Avshalom Elitzur, Roger Penrose, Juan Maldacena, and Leonard Susskind suggest that while relativistic causality remains operationally intact, the locality assumptions underlying relativity itself may not be fundamental. The question is not whether information travels faster than light, but whether coherence is constrained globally rather than propagated locally.

The phrase faster than the speed of light is usually where discussions of quantum mechanics go wrong. It imports classical intuition into a framework where it does not apply. Quantum theory is explicit: entanglement does not allow controllable signals, messages, or energy to travel faster than c. In that narrow sense, relativity holds.

And yet something nontrivial still occurs. Entangled particles exhibit correlations that are instantaneous with respect to spatial separation and incompatible with any local hidden-variable explanation. Bell’s theorem formalized this decades ago, and experiments have confirmed it repeatedly. Nothing travels between the particles. Nothing is exchanged. And still the outcomes are coordinated.

The real question, then, is not speed. It is structure. In quantum mechanics, the wavefunction describes a system as a whole, not as a collection of independent parts. Measurement does not transmit information from one particle to another; it reveals a relational constraint already present in the system. The coordination appears not because something moves through space, but because the system was never separable in the first place.

This is where classical causality begins to fail as a metaphor. That failure becomes explicit in interaction-free measurement, most clearly articulated by Avshalom Elitzur. These experiments demonstrate that information can be obtained without physical interaction, without energy exchange, without contact. The mere possibility of interaction alters outcomes. What could have happened constrains what does happen.

Elitzur has emphasized that this does not violate relativity in the operational sense. No signal is sent. No message travels. And yet the system behaves as though it is enforcing a global consistency condition rather than responding to step-by-step local cause and effect. Causality, in this setting, behaves less like transmission and more like constraint.

Once that door is open, time itself becomes unstable as a simple ordering principle.

The fundamental equations of quantum mechanics are largely time-symmetric. They do not privilege past over future. The arrow of time appears emergent, not fundamental. Several interpretations take this seriously, treating quantum events as constrained by both past and future boundary conditions rather than driven exclusively forward. This does not imply paradox. It implies coherence.

This framing aligns naturally with Roger Penrose’s long-standing discomfort with purely forward, local causality. Penrose has argued for decades that standard quantum mechanics is incomplete, particularly with respect to collapse, and that gravity and spacetime geometry must participate in objective state reduction. In his view, collapse is not merely an update of knowledge, but a physical process tied to spacetime structure itself.

There is also a revealing human detail in how Penrose describes the origins of these ideas.

In recounting an early insight that would later become foundational to his work on spacetime geometry, Penrose describes experiencing a strong, almost autonomic sense of elation — not intellectual excitement, but bodily recognition. Importantly, he did not immediately understand why he felt it. Only the following day did he deliberately search his memory, retracing his thoughts to identify what had preceded that sensation. What stood out was not a calculation or a conversation, but the moment, while crossing the road, when the geometric role of tensors had suddenly cohered. The ordering matters. The bodily signal came first. The conscious recognition came later. The formal validation arrived decades after that.

No causal claim needs to be made to observe this pattern. One can simply note that the autonomic nervous system appears capable of registering global coherence — the sudden resolution of constraint — before the conscious mind has language for it, and long before the external world supplies confirmation.

In this sense, the elation does not represent anticipation of a future reward. It reflects alignment with a structure that is already complete in a deeper sense, even if its consequences unfold slowly in time. This is not retrocausality as message-passing from the future. It is retrocausality in a weaker, more defensible form: future-consistent structure influencing present perception without signaling, prediction, or paradox.

If physical law is fundamentally geometric — constrained across spacetime rather than propagated step by step — then recognition of such structure need not wait for temporal sequence to play out. The nervous system may respond not to outcomes, but to coherence itself.

This perspective has gained independent support from a different direction. In the ER = EPR correspondence, proposed by Juan Maldacena and developed further by Leonard Susskind, Einstein–Rosen bridges and quantum entanglement are identified as two descriptions of the same underlying structure.

In this framework, spacetime connectivity itself may emerge from entanglement. Distance, locality, and even causal structure are no longer taken as fundamental primitives, but as consequences of how quantum systems are correlated.

It is important to be precise here. ER = EPR is often presented as preserving relativity because it forbids superluminal signaling. That statement is technically correct — but it may be incomplete.

What ER = EPR suggests is not that relativity is wrong, but that the locality assumptions underlying relativity may not be fundamental. If spacetime geometry itself emerges from entanglement structure, then relativistic causality becomes an effective description rather than a primitive one. Apparent “violations” are not violations of relativistic equations, but indications that relativity may be a low-energy, large-scale limit of a deeper theory.

This is the frontier. The question is no longer whether faster-than-light signals exist — they do not — but whether the constraints that select outcomes are confined to light cones at the most fundamental level. Increasingly, quantum gravity research suggests they may not be.

From this perspective, ER = EPR does not rescue locality.

It redefines it.

Biological Bridge: Mother, Baby, Adult

This way of thinking matters because biological systems are not born isolated — they are formed in relationship, and that relationship does not end cleanly at physical separation.

From conception onward, mother, embryo, infant, and later adult participate in a coupled physiological and energetic system. Gametes merge, cells divide, tissues differentiate, and nervous systems form within a shared biochemical, electromagnetic, and temporal environment. The child’s earliest organization is inseparable from the mother’s state, and that shared origin leaves an imprint long before language, memory, or explicit cognition emerge.

If entanglement is understood not as communication but as shared constraint, then it becomes reasonable to ask whether systems that arise together retain some degree of relational sensitivity even after separation. Not signals. Not messages. But correlation — a reduced separability at the level that matters.

In this framing, perception is not unidirectional and not limited to conscious awareness. It may be mutual. The baby may register the mother, the mother the baby, and later the adult child the parent, not because information is exchanged, but because their states were once part of a single, continuous system and may remain partially aligned in ways that are not fully captured by classical models.

This does not require faster-than-light signaling. It does not require violation of causality. It requires only that correlations established during physical continuity are not immediately erased by spatial separation — much as entangled quantum systems remain correlated even when classical contact has ended.

If spacetime itself can emerge from entanglement, as suggested by ER = EPR, then biological relationships forged during shared development may also preserve nonlocal structure — not as force or influence, but as ongoing relational coherence.

In this sense, perception is not something one organism does to another. It is something that arises between mother, baby, and adult — a sensitivity to compatibility, disruption, or alignment within a shared history.

The nervous system may be especially tuned to this kind of coherence. Autonomic responses can arise without conscious mediation, registering shifts that are relational rather than sensory. What is perceived is not an external signal, but a change in a shared state.

This is not a claim of mechanism. It is a statement of possibility. And it places biology exactly where it belongs in this discussion — not as an exception to physics, but as a domain where questions of entanglement, time, and constraint become unavoidable.

If information is defined narrowly — as message transmission — then quantum mechanics forbids anything faster than light. That prohibition is absolute. But if information is understood as constraint, correlation, boundary condition, or relational structure, then quantum mechanics already operates outside classical temporal intuition.

The universe does not appear to compute outcomes sequentially.

It satisfies them globally.

The speed of light may limit what can be sent.

It may not limit what can be correlated.

And it may not limit how meaning arises in physical systems.

That is the question hiding underneath faster than c.

References

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Penrose R. The Emperor’s New Mind. Oxford University Press, 1989.

Penrose R. Shadows of the Mind. Oxford University Press, 1994.

Penrose R. On the gravitational collapse of quantum wavefunctions. General Relativity and Gravitation, 1996.

Maldacena J. The large-N limit of superconformal field theories and supergravity. Advances in Theoretical and Mathematical Physics, 1998.

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Susskind L. Entanglement is not enough. Fortschritte der Physik, 2016.

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© Courtney Hunt, MD, 2026