Wormholes are not a shortcut to the universe, but a bridge between the future and the past

Wormholes are not tunnels to travel to other parts of the universe, but bridges between two opposing timelines that can explain what happened before the Big Bang.

Wormholes are not shortcuts to the universe, but bridges between the future and the past

Wormholes are not tunnels to other parts of the universe, but rather a bridge between two conflicting times that could explain what happened before the Big Bang.

Wormholes are often thought of as tunnels through space or time, and shortcuts through the universe.However, this image is based on a misinterpretation of the work of physicists Albert Einstein and Nathan Rosen.

In 1935, while studying the behavior of particles in regions of extreme gravity, Einstein and Rosen introduced what they called a bridge: a mathematical connection between two perfectly symmetrical copies of spacetime.It is not intended as a road map, but as a way of maintaining coherence between gravity and quantum physics.It was only later that Einstein-Rosen bridges were connected to wormholes, despite having little to do with the original idea.

But in a new study, my colleagues and I show that the first Einstein-Rosen bridge points to something even more unknown (and more important) than the black hole.

The puzzle that Einstein and Rosen faced was not about space travel, but about how quantum fields interact with time.Interpreted in this way, the Einstein-Rosen bridge is like a mirror in spacetime: a connection between two arrows of time.

Quantum mechanics governs nature at the smallest scales, such as particles, while Einstein's general theory of relativity deals with gravity and spacetime.Reconciliation of the two remains one of the most profound problems in physics.And interestingly, our reinterpretation may offer a way to achieve it.

A misinterpreted legacy

The wormhole interpretation emerged decades after Einstein and Rosen's work, as physicists speculated about transitions from one side of spacetime to the other, particularly in research in the late 1980s.

But those same analyzes also showed how speculative the idea was: such travel is forbidden in general relativity.The bridge closes faster than light can pass through it, making it impassable.Einstein-Rosen bridges are therefore unstable and unobservable.Mathematical structures, not portals.

However, the wormhole metaphor flourished in popular culture and speculative physics.The idea that black holes can connect distant regions of the universe or act as time machines has inspired countless articles, books and movies.

However, there is no observational evidence for macroscopic wormholes, nor is there any compelling theoretical reason to expect them in Einstein's theory.Although speculative extensions of physics—such as strange forms of matter or changes in general relativity—have been proposed to support such structures, they remain unpredictable and highly speculative.

Two arrows of time

Our recent work revisits the Einstein-Rosen bridge puzzle with a modern quantum interpretation of time, building on ideas developed by Sravan Kumar and João Marto.

Most of the fundamental laws of physics do not distinguish between past and future or between left and right.If you reverse time or space in your equation, the laws still apply.Taking these asymmetries seriously leads to a different interpretation of the Einstein-Rosen bridge.

Instead of a tunnel through space, it can be thought of as two additional components of the quantum state.One is that time flows forward;the other flows backwards from its mirror position.

This symmetry is not a philosophical preference.Once infinities are ruled out, quantum evolution at the microscopic level should remain complete and reversible, even in the presence of gravity.

The bridge expresses the fact that both time components are necessary to describe a complete physical system.In ordinary situations, physicists ignore the time-reversal component by opting for a single arrow of time.

But near black holes or in expanding and collapsing universes, both directions must be included for a coherent quantum description.This is where Einstein-Rosen bridges naturally arise.

Solving the information paradox

At the microscopic level, the bridge allows information to cross what appears to be the event horizon, the point of no return.The information does not disappear;it continues to develop, but in the opposite direction of time, reflected.

This process offers a natural solution to the well-known black hole information paradox.In 1974, Stephen Hawking showed that black holes emit heat and can eventually be ejected, apparently erasing all information that entered them, contradicting the quantum theory that radiation should store information.

Confusion arises only if we insist on defining horizons with a single, one-sided arrow of time extended to infinity, an assumption not required by quantum mechanics itself.

If a full quantum description includes both time directions, nothing is really lost.Information leaves our temporal direction and reappears in the transverse direction.Absoluteness and causality are preserved, without introducing new exotic physics.

These ideas are difficult to grasp because we are macroscopic beings who experience only one direction of time.On a daily scale, disorder or entropy tends to increase.A highly ordered state naturally turns into a disordered one, not the other way around.This gives us the arrow of time.

But quantum mechanics allows for more subtle behaviorAnd evidence for this hidden structure already existsThe cosmic microwave background—after the light from the Big Bang—shows a small but persistent asymmetry: a preference for spatial orientation over its mirror image.

This discrepancy has puzzled cosmologists for two decades.Standard models attribute it to very low probability, unless special quantum components are involved.

Echoes of a previous universe?

This image is of course connected to a deeper possibility.The so-called Big Bang was perhaps not an absolute beginning, but rather a renaissance: a quantum transition between two phases that changed over time in the evolution of the universe.

In such a case, black holes can act as bridges not only between temporal directions, but also between different cosmological epochs.Our universe may be the interior of a black hole that formed somewhere in the universe.It could have formed when a closed space-time region collapsed, re-energized and began to expand, like the universe we see today.

If this picture is correct, it also provides a way to determine the observations.Remnants of the pre-leap phase – such as small black holes – can survive evolution and reappear in our expanding universe.Some of the invisible matter we call dark matter may actually be composed of these remnants.

According to this view, the Big Bang emerged from previous contraction conditions.Wormholes are unnecessary: ​​the bridge is temporary, it has no place, and the Big Bang becomes a doorway, not a beginning.

This reinterpretation of the Einstein-Rosen scores provides no intergalactic shortcuts, no time travel, no scientific wormholes, and no superspace.What it offers is much deeper.It provides a picture of a gravitationally bounded universe where spacetime is composed of opposite time directions and where our universe may have had a pre-Big Bang history.

It doesn't overturn Einstein's relativity or quantum physics: it completes them.The next revolution in physics may not take us faster than light, but it may reveal that time, deep in the microscopic world and in a hopping universe, flows in both directions.

Wormholes are often depicted as tunnels through space or time, shortcuts through the universe.But this image is based on a misinterpretation of the work of physicists Albert Einstein and Nathan Rosen.

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