Although in theory time can be divided into infinitely small intervals, the Planck time, which is approximately equal to 10 -43 seconds, is considered the smallest physically meaningful time interval. This final limit means that two events cannot be separated by time, which will be less than this interval. But now, in the new work, physicists have concluded that the shortest physically meaningful time interval can actually be several orders of magnitude longer than Planck's time. In addition, physicists have demonstrated that the existence of such a minimum time changes the basic equations of quantum mechanics, and since quantum mechanics describes all physical systems on the smallest scales, this also changes the description of all quantum mechanical systems.
Scientists Mir Faisal from the University of Waterloo and the University of Lethbridge in Canada, Mohammed Khalil from the University of Alexandria in Egypt and Sauriy Das from the University of Lethbridge published an article titled “Crystals of time from minimal time uncertainty” in European Journal of Physical Journal C.
“It may be that in the Universe the minimum time scale is actually much longer than Planck’s time, and this can be verified experimentally,” said Faisal Phys.org.
Planck's time is so short that no experiment has ever been close enough to test it directly - the most accurate tests can access the time interval of the order of 10-17 seconds.
Nevertheless, there is a strong theoretical support for the existence of Planck’s time in various approaches to quantum gravity, such as string theory, loop quantum gravity and perturbative quantum gravity. Almost all of these approaches suggest that it is impossible to measure a length shorter than Planck’s length, and in a broad sense, time is shorter than Planck’s time as well, since Planck’s time is defined as the time required for light to overcome one unit of Planck’s length in vacuum.
Girding the latest theoretical research, scientists looked into the question of the structure of time - in particular, they touched the old question: is it discrete time or is it continuous?
“In our work, we assumed that time is discrete in nature, and also suggested ways to experimentally test this assumption,” says Faisal.
One possible test involves measuring the rate of spontaneous emission of a hydrogen atom. The advanced quantum mechanical equation predicts a slightly different rate of spontaneous emission than the usual equation predicted, within the uncertainty range. The proposed effects can also be observed in the decay rate of particles and unstable nuclei.
Based on their theoretical analysis of the spontaneous emission of hydrogen, scientists estimate that the minimum time interval should be several orders of magnitude larger than the Planck time, but not more than a certain value set by previous experiments. Further experiments can reduce this minimum time limit or determine its exact value.
Scientists also suggest that the proposed changes in the basic equations of quantum mechanics could change the very definition of time. They explain that the structure of time can be regarded as crystalline, consisting of discrete, regularly repeated segments.
At a more philosophical level, the argument of discrete time means that our perception of time as something constantly current is just an illusion.
“The physical universe, in fact, is like a movie in a movie when a series of still images creates the illusion of moving images,” says Faisal. “Thus, if we seriously take this point of view, our conscious perception of physical reality, based on continuous movement, will become an illusion produced by the discrete mathematical structure underlying time.”
“This sentence makes the physical reality platonic in nature,” he says, pointing to Plato’s argument that true reality exists independently of our senses. “However, unlike other theories of platonic idealism, our proposal can be tested experimentally and attributed not only to philosophy.”
The article is based on materials .
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