I understand that eventually in this discussion there will be some unexplained universal law that we will all have to accept as a God's law and build every physics proof upon that. But I want to know if these 2 things written in bold are the 'built on God's law and explainable' ones or are they themselves the God's laws.

Can quantum entangled particles transfer information without any loss of time. Therefore making their 'entangling ether connection' faster than c. Now don't start with the measuring will break down the entangled quantum state stuff because my second question is about the measurement/observation. From all resources regarding the quantum entanglement that I looked into, they all start with Alice measuring her particle's state and so on .. BUT what the heck does this "Alice's measurement" mean, I mean there could be a caterpillar inside Alice's box of particle, and maybe the caterpillar measured it first, it's such a dumb way to explain the collapse. Isn't it like the classical mechanics relative velocity thingy, where frame of reference decides if the particle is still entangled for that particular observer. And so unlike the awesome pn junction tunneling that enables awesome tiny transistors, is "entanglement" just like "relative velocity" and a mere concept that can't be used to make brand new quantum routers for high speed communication?
Also lets not pretend to be able to perceive higher dimension/solution of a gazzilion degree multivariate quantum equation to explain entanglement. Cheers!


closed as unclear what you're asking by WillO, tparker, ZeroTheHero, Jon Custer, user191954 Sep 14 '18 at 2:22

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  • $\begingroup$ The answer to your first boldfaced question is emphatically "no". Re Alice and her caterpillar, this has nothing to do with entanglement; you could ask the same question about any observation of any quantum state whether entangled or not, and the question was answered by von Neumann's theorem which says, in essence, that it doesn't matter whether you say the collapse occurs when the caterpillar observes the particle or that it occurs when you observe the particle;the two formulations are observationally equivalent. $\endgroup$ – WillO Sep 13 '18 at 20:53
  • $\begingroup$ Please use more formal language. It's ok to be informal, but "Idek man", "gazzilion degree multivariate", "dumb way to explain", and "relative velocity thingy" are way too casual. $\endgroup$ – user191954 Sep 14 '18 at 2:21

Answering your main question:

You cannot use entanglement to transfer information faster than light. There is a mathematical result called the no-communication theorem that proves this. To get some intuition as to why this is true, we must understand what entanglement actually means. Entanglement means that parts of a system are correlated; if parts of an entangled system are measured repeatedly, the lists of measurements, when compared, will be related to each other. This means that if you already have information about how the parts were entangled, then you can use that information to gain knowledge about measurements of the other parts just by measuring your part. But this isn't a transfer of information; rather, it's a conversion of information you already had by combining it with information you got from the measurement. And if you don't know anything about the specific way that things are entangled, then you can't determine anything about the other parts of the system.

To illustrate, let's look at an example. Suppose we have a pair of coins, which can be measured to land on either heads or tails. Each coin has a 50% chance of landing on heads (H) and a 50% chance of landing on tails (T). Let's also assume that these coins are special: it is possible to entangle the two coins. If the coins are unentangled, then the results of one coin are completely unrelated to the other coin: HH, HT, TH, and TT are all equally likely outcomes. But if the coins are entangled, this may not be the case. There are multiple ways to entangle the coins: for example, they may be entangled such that when one coin lands on heads, the other coin also lands on heads, so HH and TT are the only outcomes that happen. They could also be entangled such that when one coin lands on heads, the other coin lands on tails, so HT and TH are the only outcomes that happen. But in all of these cases, if you were to look at only one coin, you would see the same outcome: 50% heads, 50% tails, regardless of if or how the coins are entangled. If you already know, for example, that the coins are entangled to have the same outcome, then you can tell how the other coin will land without looking at the other coin, but this information didn't magically flow from the other coin to your brain; you already knew this information, and the determination of the other coin's state is simply an application of that prior information. Likewise, if you don't know how the coins are entangled, then you can't say anything about how the other coin will land.

So we've established that, in order to know anything about the state of faraway parts of the system, you have to know how the state was entangled in the first place. No matter which way you use to obtain this information, it requires some form of at-most-lightspeed ("classical") communication. If you obtain this information by comparing measurements between entangled parts, then you must classically communicate with the person making the measurement, or you must move between the two entangled parts (which must necessarily be slower than the speed of light); if you decide to obtain this information by making the entangled pair yourself, then you must bring the entangled pair close enough to interact, which means bringing them close enough that something traveling at most at the speed of light could travel between one and the other. So, in order to be able to predict the outcomes of faraway measurements, you must have already communicated with them classically, and, in effect, the information you hold was acquired through that classical communication.


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