{"id":22902,"date":"2025-11-07T08:50:50","date_gmt":"2025-11-07T13:50:50","guid":{"rendered":"https:\/\/www.ecoticias.com\/en\/?p=22902"},"modified":"2025-11-07T08:50:50","modified_gmt":"2025-11-07T13:50:50","slug":"scientists-create-time-traveling-light","status":"publish","type":"post","link":"https:\/\/www.ecoticias.com\/en\/scientists-create-time-traveling-light\/22902\/","title":{"rendered":"Scientists create time-traveling light \u2014 It left its box before it entered and flowed towards the past"},"content":{"rendered":"

Picture a light that behaves in such a freakish manner that it seems to emerge from a substance before it has a chance to get in, thus opposing our common understanding of cause and effect. This is not science fiction, but rather reality in the realm of quantum physics.<\/strong> Scientists at the University of Toronto have done something that at first sounds like it is impossible\u2014namely, they have detected a photon that has spent negative time in an excited atomic state.<\/p>\n

Quantum physicists showed that light could go back in time<\/h2>\n

In this revolutionary experiment, photons were passed through a cloud of rubidium atoms that were ultracold, and scientists accurately determined how those atoms became excited.<\/strong> In a phenomenon that defies our understanding of basic causation in physics, scientists found that when light passes through atoms, a group delay effect also develops that is actually negative, meaning that photons emerged from a cloud of atoms before those atoms were fully excited by those same atoms.<\/p>\n

In their complex setup, lead researcher Daniela Angulo\u2019s team utilized two highly specialized lasers that produced such extraordinary findings. A resonant pulse was directly applied to rubidium atoms, while a non-resonant probe was utilized to detect small changes in the material\u2019s refractive index<\/strong> through a process known as a cross-Kerr effect. This highly sensitive detection process enabled lead researcher Angulo\u2019s team to observe such an extraordinary aspect of negative-time events.<\/p>\n

In fact, when processed, it was found that the average value of the excited times was between negative eight-tenths of a characteristic lifetime and slightly more than half a lifetime, thereby proving its probabilistic component. In fact, it was also seen that negative values emerged when there was a narrowband pulse near an atomic transition, thereby leading to highly dispersive conditions that made an impossibility a reality.<\/p>\n

Why Einstein’s Relativity is completely secure against Quantum Time Travel<\/h2>\n

Although this discovery has such dramatic implications, it does not go against Einstein’s theory of relativity<\/strong> or the laws of physics. This is because photons in this quantum travel through time are not transmitting information at a speed greater than that of light, thus violating the universal speed limit according to Einstein’s theory of special relativity<\/a>. Rather, these particles are illustrating that a quantum superposition of particles is capable of existing in multiple states at one time.<\/p>\n

\u201cA negative time delay is a paradox in itself,\u201d Josiah Sinclair, a former doctoral student, explains, \u201calthough what it actually means is that if you constructed a ‘quantum’ clock to measure just how long those atoms spent in the excited state, it would actually go backwards in a particular situation.\u201d<\/p><\/blockquote>\n

This phenomenon is essentially an internal timing of interaction between atoms and light, as it maintains all of the principles of relativistic physics while also subtly illustrating an aspect of quantum mechanics.<\/p>\n

What negative time discoveries mean for revolutionary quantum technologies<\/h2>\n

This new finding starts to replace vague speculations concerning pulse front reshaping with concrete predictions concerning the dwell time in excited atomic states. This work offers precise error-bar assignments, which should help resolve previous misunderstandings involving fast light pulses or superluminality in quantum optics and also pave a new path toward new technological applications. Attention is already drawn to the possible use of this particular phase sensitivity within new quantum sensing tools.<\/p>\n

This experiment is a clear insight that quantum mechanics is full of phenomena<\/a> that go against common sense in terms of understanding time and causation at a microscopic level. Although the photons aren\u2019t actually moving back in time, they’re proving that time itself is a completely different phenomenon at a microscopic level<\/strong> than it is at a macroscopic level, offering a complete paradigm shift in our understanding of quantum technology.<\/p>\n","protected":false},"excerpt":{"rendered":"

Picture a light that behaves in such a freakish manner that it seems to emerge from a substance before it … <\/p>\n

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