![\"](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/02\/a12cf210b6877e2803a8656daae572ec.jpeg\"\/)
<\/p>\nWhen you buy through links on our articles, Future and its syndication partners may earn a commission.<\/p>\n
<\/p>\n
An illustration of matter pouring into a black hole, crossing an Einstein-Rosen bridge and emerging in another region of the universe. | Credit: Robert Lea (Created with Canva)<\/p>\n
This article was originally published at The Conversation.<\/a> The publication contributed the article to Space.com’s Expert Voices: Op-Ed & Insights<\/a>.<\/p>\n Wormholes<\/a> are often imagined as tunnels through space or time \u2014 shortcuts across the universe. But this image rests on a misunderstanding of work by physicists Albert Einstein<\/a> and Nathan Rosen.<\/p>\n In 1935, while studying the behaviour of particles in regions of extreme gravity, Einstein and Rosen introduced what they called a “bridge”<\/a>: a mathematical link between two perfectly symmetrical copies of spacetime<\/a>. It was not intended as a passage for travel, but as a way to maintain consistency<\/a> between gravity and quantum physics. Only later did Einstein\u2013Rosen bridges become associated with wormholes, despite having little to do with the original idea.<\/p>\n But in new research<\/a>, my colleagues and I show that the original Einstein\u2013Rosen bridge points to something far stranger \u2014 and more fundamental \u2014 than a wormhole.<\/p>\n The puzzle Einstein and Rosen were addressing was never about space travel, but about how quantum fields behave in curved spacetime. Interpreted this way, the Einstein\u2013Rosen bridge acts as a mirror in spacetime: a connection between two microscopic arrows of time.<\/p>\n Quantum mechanics governs nature at the smallest scales such as particles, while Einstein’s theory of general relativity <\/a>applies to gravity and spacetime. Reconciling the two remains one of physics’ deepest challenges. And excitingly, our reinterpretation may offer a path to doing this.<\/p>\n A misunderstood legacy<\/p>\n The “wormhole” interpretation emerged decades after Einstein and Rosen’s work, when physicists speculated about crossing from one side of spacetime to the other, most notably in the late-1980s research<\/a>.<\/p>\n But those same analyses also made clear how speculative the idea was: within general relativity, such a journey is forbidden. The bridge pinches off faster than light could traverse it, rendering it non-traversable. Einstein\u2013Rosen bridges are therefore unstable and unobservable \u2014 mathematical structures, not portals.<\/p>\n Nevertheless, the wormhole metaphor flourished in popular culture and speculative theoretical physics. The idea that black holes<\/a> might connect distant regions of the cosmos \u2014 or even act as time machines<\/a> \u2014 inspired countless papers, books and films.<\/p>\n Yet there is no observational evidence for macroscopic wormholes, nor any compelling theoretical reason to expect them within Einstein’s theory. While speculative extensions of physics \u2014 such as exotic forms of matter<\/a> or modifications of general relativity<\/a> \u2014 have been proposed to support such structures, they remain untested and highly conjectural.<\/p>\n An artist’s interpretation of utilizing a wormhole to travel through space. | Credit: NASA<\/p>\n Two arrows of time<\/p>\n Our recent work revisits the Einstein\u2013Rosen bridge puzzle using a modern quantum interpretation of time, building on ideas developed by Sravan Kumar and Jo\u00e3o Marto.<\/p>\n Most fundamental laws of physics<\/a> do not distinguish between past and future, or between left and right. If time or space is reversed in their equations, the laws remain valid. Taking these symmetries seriously leads to a different interpretation of the Einstein\u2013Rosen bridge.<\/p>\n Rather than a tunnel through space, it can be understood as two complementary components of a quantum state. In one, time flows forward; in the other, it flows backward from its mirror-reflected position.<\/p>\n This symmetry is not a philosophical preference. Once infinities are excluded, quantum evolution must remain complete and reversible at the microscopic level \u2014 even in the presence of gravity.<\/p>\n The “bridge” expresses the fact that both time components are needed to describe a complete physical system. In ordinary situations, physicists ignore the time-reversed component by choosing a single arrow of time.<\/p>\n But near black holes, or in expanding and collapsing universes, both directions must be included for a consistent quantum description. It is here that Einstein\u2013Rosen bridges naturally arise.<\/p>\n Solving the information paradox<\/p>\n At the microscopic level, the bridge allows information to pass across what appears to us as an event horizon<\/a> \u2013 a point of no return. Information does not vanish; it continues evolving, but along the opposite, mirror temporal direction.<\/p>\n This framework offers a natural resolution to the famous black hole information paradox. In 1974, Stephen Hawking showed<\/a> that black holes radiate heat and can eventually evaporate, apparently erasing all information about what fell into them \u2014 contradicting the quantum principle that evolution must preserve information.<\/p>\n The paradox arises only if we insist on describing horizons using a single, one-sided arrow of time extrapolated to infinity \u2014 an assumption quantum mechanics itself does not require.<\/p>\n If the full quantum description includes both time directions, nothing is truly lost. Information leaves our time direction and re-emerges along the reversed one. Completeness and causality are preserved, without invoking exotic new physics.<\/p>\n These ideas are difficult to grasp because we are macroscopic beings who experience only one direction of time. On everyday scales, disorder \u2014 or entropy \u2014 tends to increase. A highly ordered state naturally evolves into a disordered one, never the reverse. This gives us an arrow of time.<\/p>\n But quantum mechanics allows more subtle behaviour. Intriguingly, evidence for this hidden structure may already exist. The cosmic microwave background \u2014 the afterglow of the Big Bang<\/a> \u2014 shows a small but persistent asymmetry<\/a>: a preference for one spatial orientation over its mirror image.<\/p>\n This anomaly has puzzled cosmologists for two decades. Standard models assign it extremely low probability \u2014 unless mirror quantum components are included.<\/p>\n Echoes of a prior universe?<\/p>\n This picture connects naturally to a deeper possibility. What we call the “Big Bang” may not have been the absolute beginning, but a bounce \u2014 a quantum transition between two time-reversed phases of cosmic evolution.<\/p>\n In such a scenario, black holes could act as bridges not just between time directions, but between different cosmological epochs. Our universe might be the interior of a black hole<\/a> formed in another, parent cosmos. This could have formed as a closed region of spacetime collapsed, bounced back and began expanding as the universe we observe today.<\/p>\n If this picture is correct, it also offers a way for observations to decide. Relics from the pre-bounce phase \u2014 such as smaller black holes \u2014 could survive the transition and reappear in our expanding universe. Some of the unseen matter we attribute to dark matter could, in fact, be made of such relics.<\/p>\n In this view, the Big Bang evolved from conditions in a preceding contraction. Wormholes aren’t necessary: the bridge is temporal, not spatial \u2014 and the Big Bang becomes a gateway, not a beginning.<\/p>\n![\"An](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/02\/fa309aa1c41f969a6e77c691a0ff8212.jpeg\"\/)
<\/p>\n