Out on the edge-physics - Page 1
Forum section: electronics / general

author: quantumfall
author_rank: Regular Contributor
timestamp: April 14, 2012, 07:40:24 pm
content: Thinking about how fast a signal or data, whatever information can be moved from place to place. Is it the stretchy bit of "what we are in that makes it how it is ? The speed of light is fundamental here so its said, I have a dislike of absolute

author: IanB
author_rank: Super Contributor
timestamp: April 14, 2012, 08:00:15 pm
content: "Information" gets a precise technical meaning in physics. The limit to how fast information can be communicated from one place to another is the speed of light in a vacuum. And the speed of light in a vacuum is not absolute, it is a physical constant. Special and general relativity show that many things are not absolute at all, but relative to the position of an observer.

author: G7PSK
author_rank: Super Contributor
timestamp: April 14, 2012, 08:09:26 pm
content: Except when it comes to quantum information then the transfer is faster than light.

author: IanB
author_rank: Super Contributor
timestamp: April 14, 2012, 08:13:36 pm
content: Quote from: G7PSK on April 14, 2012, 08:09:26 pmI don't believe quantum theory includes any exceptions that violate the limit on the speed of information transfer. This is something that is pretty well embedded in current theoretical understanding. For instance, there was recently a big hoo-ha when an experiment suggested signals could exceed the speed of light by even a minute fraction. It was such a big claim that the repercussions would have been enormous had it been substantiated.

author: G7PSK
author_rank: Super Contributor
timestamp: April 14, 2012, 08:42:44 pm
content: Entangled pairs is the name of the game. Move one half of the pair and the other instantly follows, faster than light. Just now reading about it it in New scientist.

author: IanB
author_rank: Super Contributor
timestamp: April 14, 2012, 08:53:05 pm
content: Quote from: G7PSK on April 14, 2012, 08:42:44 pmRight. But if you continue reading you will find that although entanglement appears to involve instantaneous action at a distance, it does not provide any way to use that connection to transfer information faster than light. It's one of those fundamental laws like conservation of mass and energy. You just can't get round it.

author: quantumfall
author_rank: Regular Contributor
timestamp: April 14, 2012, 08:53:49 pm
content: I'm did not mean to post this, even if it is a catalyst to discussion, I should have learner plates. Or its to easy to post // ?

author: AntiProtonBoy
author_rank: Frequent Contributor
timestamp: April 15, 2012, 08:44:43 am
content: QuoteI'm really out of my depth here, but I don't think you can regard quantum states as information in a traditional sense. For example, no two electrons can occupy the same quantum state in the universe; hence if one electron changes state, then every other electron in the universe changes their states instantly. But you can not use this property to convey information or transmit anything meaningful.Speaking of weird quantum stuff, Aussie researchersbuilt a random number generatorthat harvests numbers at 2 Gbps from the vacuum energy of space, which is guaranteed to be random according to quantum theory.Onya skips!