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+--- Thread: Article New type of time crystal + Spacetime is not a continuum, it's made up of pieces (/thread-17604.html)
New type of time crystal + Spacetime is not a continuum, it's made up of pieces - C C - Mar 17, 2025
Spacetime is not a continuum, it's made up of discrete pieces
https://iai.tv/articles/spacetime-is-not-a-continuum-its-made-up-of-discrete-pieces-auid-3108?_auid=2020
INTRO: Much of modern physics hinges on the notion of a smooth ‘continuum’. But as Professor of Theoretical Physics Sumati Surya argues, our lived experience point to something else: discreteness. Surya argues that spacetime isn’t infinitely divisible but instead built from discrete elements and their causal relationships – there is a “fundamental minimal size below which spacetime loses its meaning”.
EXCERPT: The quantum spacetime substance must therefore incorporate this essential causal structure. This is the starting hypothesis of causal set quantum gravity. It further posits that spacetime doesn’t quite dissolve into dust at the Planck scale, but becomes a discrete graph where elements are ordered by causality. Mathematically, this is a locally finite poset, or causal set. The causal order of spacetime corresponds to the order relation in the poset, while the (missing) volume is obtained by counting the number of elements that lie between any two ordered elements. Thus, the continuum causal structure, which has no limit to how small you can go, is replaced by a locally finite structure, the causal set, where there is a fundamental minimal size below which spacetime loses its meaning.
If spacetime is discrete, how do we perceive the seeming continuity of our experiences? The answer is that we don’t actually have continuous experiences. All of known physics rests on the understanding that there is a finite experimental limitation in any physical experience or measurement, i.e., a finite resolution. The mathematics of the continuum is simply a convenient way to frame our present theories.
Nevertheless, one would like to see how the continuum approximation ‘emerges’ from the underlying discreteness. Just as we readily correlate the continuous fluid that comes out of the tap every morning, with its constituent discrete water molecules, so should we do so with spacetime... (MORE - details)
Team creates time quasicrystals in diamonds (new type of time crystal)
https://artsci.washu.edu/ampersand/what-is-a-time-crystal-quasicrystal
PRESS RELEASE: In their ongoing efforts to push the boundaries of quantum possibilities, physicists in Arts & Sciences at Washington University in St. Louis have created a new type of “time crystal,” a novel phase of matter that defies common perceptions of motion and time.
The WashU research team includes Kater Murch, the Charles M. Hohenberg Professor of Physics, Chong Zu, an assistant professor of physics, and Zu’s graduate students Guanghui He, Ruotian “Reginald” Gong, Changyu Yao, and Zhongyuan Liu. Bingtian Ye from the Massachusetts Institute of Technology and Harvard University’s Norman Yao are also authors of the research, which has been published in the prestigious journal Physical Review X.
Zu, He, and Ye spoke about their achievement and the implications of catching time in a crystal.
What is a time crystal? To understand a time crystal, it helps to think about familiar crystals such as diamonds or quartz. Those minerals owe their shape and shine to their highly organized structures. The carbon atoms in a diamond interact with each other to form repeated, predictable patterns.
Much like the atoms in a normal crystal repeat patterns in space, the particles in a time crystal repeat patterns over time, Zu explained. In other words, they vibrate or “tick” at constant frequencies, making them crystalized in four dimensions: the three physical dimensions plus the dimension of time.
What makes a time crystal special? Time crystals are like a clock that never needs winding or batteries. “In theory, it should be able to go on forever,” Zu said. In practice, time crystals are fragile and sensitive to the environment. “We were able to observe hundreds of cycles in our crystals before they broke down, which is impressive.”
Time crystals have been around for a little while; the first one was created at the University of Maryland in 2016. The WashU-led team has gone one step further to build something even more incredible: a time quasicrystal. “It’s an entirely new phase of matter,” Zu said.
How is a time quasicrystal different from a time crystal? In material science, quasicrystals are recently discovered substances that are highly organized even though their atoms don’t follow the same patterns in every dimension. In the same way, the different dimensions of time quasicrystals vibrate at different frequencies, explained He, the lead author of the paper. The rhythms are very precise and highly organized, but it’s more like a chord than a single note. “We believe we are the first group to create a true time quasicrystal,” He said.
How are time quasicrystals created? The team built their quasicrystals inside a small, millimeter-sized chunk of diamond. They then bombarded the diamond with beams of nitrogen that were powerful enough to knock out carbon atoms, leaving atom-sized blank spaces. Electrons move into those spaces, and each electron has quantum-level interactions with its neighbors. Zu and colleagues used a similar approach to build a quantum diamond microscope.
The time quasicrystals are made up of more than a million of these vacancies in the diamond. Each quasicrystal is roughly one micrometer (one-thousandth of a millimeter) across, which is too small to be seen without a microscope. “We used microwave pulses to start the rhythms in the time quasicrystals,” Ye said. “The microwaves help create order in time.”
What are the potential uses of time crystals or quasicrystals? The mere existence of time crystals and quasicrystals confirms some basic theories of quantum mechanics, so they’re useful in that way, Zu said. But they might have practical applications as well. Because they are sensitive to quantum forces such as magnetism, time crystals could be used as long-lasting quantum sensors that never need to be recharged.
Time crystals also offer a novel route to precision timekeeping. Quartz crystal oscillators in watches and electronics tend to drift and require calibration. A time crystal, by contrast, could maintain a consistent tick with minimal loss of energy. A time quasicrystal sensor could potentially measure multiple frequencies at once, creating a fuller picture of the lifetime of a quantum material. First, researchers would need to better understand how to read and track the signal. They can’t yet precisely tell time with a time crystal; they can only make it tick.
Because time crystals can theoretically tick forever without losing energy, there’s a lot of interest in harnessing their power for quantum computers. “They could store quantum memory over long periods of time, essentially like a quantum analog of RAM,” Zu said. “We’re a long way from that sort of technology, but creating a time quasicrystal is a crucial first step.”
RE: New type of time crystal + Spacetime is not a continuum, it's made up of pieces - Magical Realist - Mar 20, 2025
Space intertwines with non-space like an elegantly woven and intricate tapestry. Hence being everywhere is very close to being nowhere at all. And each place is tied to every other..
RE: New type of time crystal + Spacetime is not a continuum, it's made up of pieces - Magical Realist - Mar 23, 2025
(Mar 20, 2025 10:00 PM)Magical Realist Wrote: Space intertwines with non-space like an elegantly woven and intricate tapestry. Hence being everywhere is very close to being nowhere at all. And each place is tied non-spatially to every other..