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Space and time may be emergent
2010· Idea
SpeculativeA serious idea with no experimental proof yet.
The idea that space and time are not basic ingredients but arise from something deeper, possibly quantum entanglement.
See it on the Science map →How it works
Temperature is not a property of a single molecule; it emerges from many molecules moving. Many physicists now suspect space works similarly. In AdS/CFT, a whole extra dimension appears out of a theory that does not contain it. In 2010 Mark Van Raamsdonk argued that entanglement between parts of the boundary theory acts as the stitching: remove it and the space between them pulls apart. Time may also emerge, though that is much less understood.
Why it matters
If space emerges, the goal of quantum gravity changes: instead of quantizing space, find what space is made from. It also offers a route around the infinities that arise when gravity is quantized.
Think of it like
A market price emerges from thousands of trades; no single deal contains "the price." Distance might emerge from countless entanglement links the same way.
How we know
Mathematical results in models: the Ryu-Takayanagi formula (2006) equates entanglement to areas in the interior space. No experiment yet; tests are far beyond current technology.
Still a mystery
What space emerges from in our universe, and whether time can emerge too, are unanswered.
Connections (3)
▸AdS/CFT: a working hologram (in the math) shows how space can arise, supporting Space and time may be emergentWell supported
The relationship
In AdS/CFT the boundary theory has one fewer dimension than the interior. The extra dimension is not built in; it arises from how the boundary particles are organized and entangled. That is a working demonstration that space can be an output, not an input, which supports the broader idea that our space emerges too.
How the link was found
Maldacena (1997) gave the framework. Shinsei Ryu and Tadashi Takayanagi (2006) linked interior areas to entanglement, and Mark Van Raamsdonk (2010) argued space is built from entanglement.
Is it proven?
Within the models the math is solid and widely checked. It has not been shown for our universe.
Open questions and mysteries
Time is not emergent in AdS/CFT; the boundary already has it. Whether time can emerge as space does is unknown.
▸Quantum entanglement may be the thread that weaves Space and time may be emergentSpeculative
The relationship
In holographic models, how strongly two regions of the boundary are entangled sets how close the matching regions of space are. Reduce the entanglement and the space between them stretches and eventually splits. So entanglement acts like stitching: the pattern of quantum links may decide which places count as near.
How the link was found
Mark Van Raamsdonk, 2010. Brian Swingle (2009-12) linked it to tensor networks, and Almheiri, Dong and Harlow (2015) showed space behaves like a quantum error-correcting code.
Is it proven?
Holds in mathematical models. Entanglement itself is proven; its role in building space has no experimental test yet.
Open questions and mysteries
Whether real space in our universe is woven this way, and what plays the role of the boundary, are unknown.
▸Space and time may be emergent reframes What is time, really?Speculative
The relationship
If space can emerge from entanglement, time might also be derived rather than basic. That reframes the question: not what time is made of, but what it emerges from. One proposal, from Page and Wootters (1983), says time appears as correlations between a clock and the rest of a static universe.
How the link was found
Don Page and William Wootters (1983); Carlo Rovelli's thermal-time idea (1990s); recent holography research extending space emergence toward time.
Is it proven?
Speculative. A 2013 lab experiment by Moreva and colleagues demonstrated the Page-Wootters mechanism with entangled photons, but only as a toy model.
Open questions and mysteries
Time behaves differently from space in all known physics. Emerging it is far harder, and nobody has a convincing account.