Time Dilation as an Operational Consequence of Information Processing Limits
Abstract
What is a clock? A physical system that counts distinguishable state transitions. What is time? The rate of that count.
Starting from this operational definition—together with quantum mechanics, the Margolus-Levitin bound, the holographic principle, and local Lorentz invariance—we derive relativistic time dilation rather than postulating it. The result: \(d\tau/dt=\sqrt{1-\lambda\mathcal{S}}\), where \(\mathcal{S}\) is information density and \(\lambda=4\) is calibrated by horizon saturation. We recover the Schwarzschild metric and GPS corrections. A discrete lattice model predicts energy-dependent photon delays testable by CTA-class observations (2027+); for \(\ell_I=\ell_P\) the delay is \(\sim 10^{-17}\) s over 1 Gpc, so observations constrain \(\ell_I\) rather than test \(\ell_P\) directly.
Lineage: Bekenstein (1981) → Wheeler (1990) → Jacobson (1995) → Verlinde (2010) → RIT (2024)
1. Introduction
The relationship between information and spacetime has been explored through thermodynamic derivations of Einstein's equations [3], entropic gravity [4], and computational limits on the universe [5]. These approaches assume some spacetime structure a priori. We take a different path: we show how time dilation can follow from a compact set of operational and empirical assumptions.
Our result is a framework with explicit assumptions. Given that (1) quantum mechanics accurately describes physical systems, (2) the Margolus-Levitin bound holds, (3) observers are physical systems, (4) proper time counts distinguishable state transitions, (5) the holographic principle bounds information, and (6) physics is locally Lorentz invariant, one can relate information density to gravitational redshift and recover standard relativistic kinematics.
2. Axioms
A1 (Quantum Mechanics): Physical systems evolve according to quantum mechanics with \( |\psi(t)\rangle = e^{-iHt/\hbar}|\psi(0)\rangle \).
A2 (Margolus-Levitin): The minimum time to evolve to an orthogonal state is \( \tau_\perp \geq \pi\hbar/(2E) \) where \(E\) is average energy above ground state [6].
A3 (Physical Observers): Observers are physical quantum systems with finite effective information capacity in bounded regions and energy ranges.
A4 (Operational Time): Proper time is the number of distinguishable state transitions: \( \tau = N \cdot \tau_\perp \).
A5 (Holographic Principle): Maximum information in a region is \( I_{\max} = A/(4\ell_P^2) \) where \(A\) is boundary area [1,2,7,8,9].
A6 (Local Lorentz Invariance): In any small region, physics is Lorentz invariant with maximum speed \(c\).
3. Main Theorem
An observer in a region with information density \(\rho_I\) experiences proper time at rate
where \(\mathcal{S} = \rho_I \ell_P^3\) and \(\lambda\) is calibrated (not derived) by horizon saturation (\(\lambda=4\) for a stretched horizon of thickness \(\sim\ell_P\)).
Proof. Consider a spherical region of radius \(R\) with information content \(I = (4\pi R^3/3)\rho_I\). The Bekenstein bound (with \(I\) in natural entropy units) gives \(I \leq 2\pi R E/(\hbar c)\) [1], so \(E \leq I\hbar c/(2\pi R)\); interpreting this as an effective mass \(M_I = E/c^2\) yields a Newtonian potential \(\Phi = -\beta G M_I/R\) with \(\beta = O(1)\). Using \(\ell_P^2=G\hbar/c^3\), one finds
The weak-field redshift relation gives \(d\tau/dt=\sqrt{1-\lambda\mathcal{S}}\) with \(\lambda=(4\beta/3)(R/\ell_P)\). Requiring \(d\tau/dt\to 0\) at a stretched horizon where \(\mathcal{S}\to 1/4\) calibrates \(\lambda=4\).
An observer moving at velocity \(v\) experiences
Proof. A6 implies local Lorentz invariance: in a local inertial frame, \(ds^2=-c^2dt^2+d\vec{x}^2\). Proper time satisfies \(d\tau=ds/c\), yielding \(d\tau/dt=\sqrt{1-v^2/c^2}\). A4 interprets \(\tau\) operationally as the count of distinguishable transitions without modifying the kinematics.
4. Emergent Spacetime
For spherically symmetric \(\mathcal{S}(r) = 2GM/(c^2 r\lambda)\):
This reproduces the standard GPS correction. For a satellite at \(R_S = 26{,}560\) km orbiting at \(v = 3.87\) km/s, the net time dilation gives clocks running \(38.4\,\mu\)s/day fast, consistent with the observed \(38.6\,\mu\)s/day.
Following Jacobson's approach [3] with information flux through null surfaces and local equilibrium, one can sketch a recovery of \(G_{\mu\nu} = 8\pi G T_{\mu\nu}/c^4\) from information conservation.
5. Falsifiable Prediction
On a discrete information lattice with spacing \(\ell_I\) and a central-difference operator:
Proof. The discrete d'Alembertian gives dispersion \(\omega = (2c/\ell_I)\sin(k\ell_I/2)\). Taylor expansion yields \(\omega \approx ck(1 - k^2\ell_I^2/24)\).
The group velocity is:
High-energy photons travel slower in this lattice model. For \(\ell_I = \ell_P\):
| Source distance | 1 Gpc |
|---|---|
| High energy (E1) | 1 TeV |
| Low energy (E2) | 100 GeV |
| Time delay | ~8.5 x 10^-17 s |
A millisecond-scale delay at 1 Gpc would instead imply \(\ell_I \sim 10^{-28}\) m. CTA-like observations therefore constrain \(\ell_I\) and the dispersion sign rather than directly testing \(\ell_I = \ell_P\).
6. Discussion
Within the stated assumptions, time dilation emerges from information processing limits. The logical chain is:
- Axioms A1-A6 (empirically supported or operationally motivated)
- Information has mass-energy (Bekenstein bound)
- Mass-energy creates gravitational potential
- Gravitational potential causes time dilation (equivalence principle from A6)
- Result: \(d\tau/dt = \sqrt{1-\lambda\mathcal{S}}\)
The coupling \(\lambda = 4\) is calibrated by horizon saturation once the coarse-graining scale is chosen. The dispersion coefficient \(\zeta = -1/12\) follows from the specific lattice discretization used here and should be treated as model-dependent.
This is not a claim of unique quantum gravity dynamics; rather, it is a constrained framework linking operational time to information bounds. The key observational handle is the sign and scale of any energy-dependent delay, which constrains \(\ell_I\) and the microphysical dispersion choice.
Acknowledgments. We thank the theoretical physics community for foundational work on information and spacetime.
References
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