The understanding of quantum mechanics provides no way to break the cosmic speed limit for information or mass. Nobody can say something is absolutely impossible. Humans don't know everything.
Well, it depends on the nature of the universe. The only thing I know is that verification of the entangled states of two particles is by sending a message, that propagates at the speed limit of light, between those on both sides, who are witnessing the observation of the particles. If you have a link to what the Chinese have done? I can look at it and tell you my interpretation. I'm not an expert physicist, but I'm intelligent and might be able to point something out about what they have or have not achieved.
I think that by "message" we have to mean something that the sender intended to send. That is, something that is under that person's control. I don't believe that quantum mechanics allows for that kind of control.
Well let's define "message," there's the state of the particle it is in when it's observed. And, there's the phone call, radio signal, internet connection, etc. that Alice and Bob use to tell each other about what they observed. The first message is what has "spooky action at a distance" as Einstien called it. The second message is what confirms it and is generally limited to the speed of light (or slower).
I don't know what Chinese event you two are talking about. I vaguely recall several years ago that China beamed down an entangled particle from space, but I don't know if that's the event you're talking about, or if there's something new like in the past few days.
https://www.scientificamerican.com/...stone-in-space-based-quantum-communications/# While quantum entanglement can't actually send a message, it can allow for one site to know something about the other site. So, there is a serious effort to make this a secure way of knowing what key to use in decoding a message that is sent by other means.
It was mentioned, I believe, in an article I referenced, if I recall correctly, but I don't know much more about it than that.
Faster-than-light communication is a topic of theoretical physics. And, it is hotly debated. While the theories go back almost a hundred years, they are not settled even today. That said, however, the quantum communications technologies that are being tested and developed today are not faster-than-light systems. The quantum internet and quantum encryption are all designed to transmit data under the lightspeed limit.
Exactly! As pointed out in my cite of ScientificAmerican, there is a lot of work being done to use quantum entanglement to create a higher degree of security in communications than exists today. It's based on the fact that entanglement does allow people in different places to know about something in the other place. When the wave function collapses due to observation, you know that if your particle is a 1 then the other person's particle is a 0. Your next actions can be based on that knowledge. If you have twenty particles each entangled with a particle someone else has, you can end up with a 20 digit binary number that each party knows. That could be used as a key in encrypting a message that would, of course, be sent at normal communication speed. Cool!
On that note, I haven't heard of anyone figuring out where a portion of quarks are going when they pop in and out of existence.
My understanding is that they are moving between matter and energy. Today's particle physicists measure the mass of particles in terms of electron volts, a measure of energy. An up quark weighs about 2 mega electron volts. The vacuum energy of space is between 2 and 116 electron volts per cubic centimeter. That's 10K or 1M times difference if one cubic centimeter is important, but ... ??? Maybe there's a physicist around here who can give a definite answer, but it doesn't seem to me to be totally crazy to consider energy becoming a particle and then going back to energy as a possibility.
I don't have any kind of shingle, but E = M x C-squared is touted as an example of sorts that can be manipulated in either direction, at least for armchair musing. A key player in this process is photon particle/energy. A photon is emitted or absorbed when an electron moves between orbit levels. Photons at large come from Big Sol and other stars; there's something mysterious about all this, but the secrets are beyond my grasp. I'm left with the bazaar significance of the double slit experiment.
That is consistent with the notion of a multiverse in which an infinite number of universes bubble up from the quantum foam. All possible universes exist. That is one model [loosely speaking] but we don't know if it is correct or not. It does solve a number of problems, not the least of which being that it could explain how the physical constants have the values they do, thus making atoms possible.
Corollary: If the number of universes that can exist is finite, then an infinite number of each of the universes that can exist, do exist.
Ack! I should have said if the number of different possible universes that can exist is finite, then an infinite number of each of the universes that can exist, do exist. The language gets tricky!
You aren't writing mathematical equations so it is a philosophical argument. It is a mathematical certainty It isn't infinite and never will be [because you can never reach infinite time ] We have three dimensions in space and one in time. Space-time can be treated mathematically like a fabric that stretches and twists and folds back on itself. That is the model that emerges from General Relativity. What shape is the universe? As far as cosmologists can tell, space is almost perfectly flat. But what does this mean? ... Closed, open or flat universe? https://astronomy.com/news/2021/02/what-shape-is-the-universe
If space/time isn't infinite because it can't be reached, isn't that the definition of infinity, that it 'can't be reached'?
A few devices use quantum effects, but using entanglement to improve security is down the road, assuming it's even possible. I have my doubts.
There are different ways in which something can not be reached. In this case, there is an "observable universe" which is what is inside the radius that is reachable at the speed of light. That is, what is beyond the observable universe is receding faster than the speed of light due to the expansion of the universe. So, physics says we can get NO information from outside that radius. There is clear evidence of that situation. However, that doesn't mean it is infinite. I think there are other ways in which "infinite" might be debatable. So, it's an interesting question! That's for sure!
