In the physical world, time marches in one direction, but things aren\u2019t so straight forward in the quantum realm.<\/p>\n<\/li>\n
Researchers have discovered that it\u2019s possible to speed up, slow down, or reverse the flow of time in a quantum system.<\/p>\n<\/li>\n
This isn\u2019t exactly time travel, but is instead implementing or reverting to different quantum states from different points in time.<\/p>\n<\/li>\n<\/ul>\n
In the subatomic universe of quantum physics, you can achieve things considered impossible in our flesh-and-blood physical world. Things like superposition<\/a>, entanglement<\/a>, and even teleportation<\/a> all seem possible when things go quantum. Now, scientists from the Austrian Academy of Sciences (\u00d6AW) and University of Vienna are adding a kind of time travel<\/a> to the list.<\/p>\n In a series of papers published on preprint servers and in various online journals (including Optica<\/a>, arXiv<\/a>, and Quantum<\/a>), researchers including \u00d6AW\u2019s Miguel Navascu\u00e9s and University of Vienna\u2019s Philip Walther explain the possibility of speeding up, slowing down, and even reversing the flow of time within a quantum<\/a> system.<\/p>\n Navascu\u00e9s compares the phenomenon to different movie-watching experiences. \u201cIn a theater [classical physics], a movie is projected from beginning to end, regardless of what the audience wants,\u201d he told the Spanish-language newspaper El Pa\u00eds<\/a>. \u201cBut at home [the quantum world], we have a remote control to manipulate the movie. We can rewind to a previous scene or skip several scenes ahead.\u201d<\/p>\n The researchers achieved this by \u201cevolving\u201d a single photon as it passes through a crystal<\/a>. Using an experimental device called a \u201cquantum switch,\u201d the single photon of light returns to its previous state before it ever makes the journey. In a way, this is less Doc Brown-style time travel and more about reverting or otherwise altering the states of quantum particles, or \u201ctime translation\u201d as Navascu\u00e9s described in 2020<\/a>.<\/p>\n However, this isn\u2019t exactly like a rewind button on your TV because usually, viewers can see how things got from plot point A to B\u2014just sped up and in reverse. In quantum mechanics, however, simply observing a system causes it to change, which makes it impossible to track a system\u2019s progress through time. Crucially, these rewinding protocols still work because they can be performed without knowing what the changes were<\/a> or its \u201cinternal dynamics,\u201d according to the scientists.<\/p>\n And this quantum time machine doesn\u2019t just go one direction\u2014Navascu\u00e9s said they\u2019ve also hit upon a method for going forward in evolutionary time as well. He told El Pa\u00eds:<\/p>\n \u201cTo make a system age 10 years in one year, you must get the other nine years from somewhere. In a year-long experiment with 10 systems, you can steal one year from each of the first nine systems and give them all to the tenth. At the end of the year, the tenth system will have aged 10 years; the other nine will remain the same as when the experiment began.\u201d<\/p>\n<\/blockquote>\n Sadly, these sci-fi findings in the quantum world can\u2019t be sized up to send humans backward and forward in time, because a single human represents a mind-boggling amount of information to \u201crejuvenate\u201d\u2014in fact, the scientists estimate it would take millions of years to pull it off for just one second.<\/p>\n But for the teams at \u00d6AW and the University of Vienna, the point isn\u2019t jetting off to the distant future<\/a>, but the ability to increase the capability of quantum processors by arming them with the possibility of reversing errors in a system. After all, if life had a rewind button, wouldn\u2019t you use it?<\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n Get the Issue<\/a><\/p>\n Photo credit: Hearst Owned<\/p>\n\n
![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/ac3e01872aefc7ef7678324dedd5baab.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/3776b633c32b3be6e3f5d9f587a7f7df.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/2703559ecea1884f1325b6db16fb9940.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/c7d6726938f9c62bcabf1eadee81b6c4.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/00686f82100a78d8ec7fb788491ee592.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/a99224c3f9fb5222d1da1def734d9296.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/367fbd7c38736863573f832d6d05baa1.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/b5bd4f1a2820732bd18c5832e095b6eb.jpeg\"\/)
<\/p>\n![\"Photo](\"https:\/\/www.europesays.com\/us\/wp-content\/uploads\/2025\/07\/27698c99ec42bac79249186d21468752.jpeg\"\/)
<\/p>\n