Possible warp drive may allow Alpha Centauri to be reached "in a mere two weeks"

[Synobun]

I'm still haunted by Fermi's question. If the odds of life and intelligence arising are so great, then the galaxy should be swarming with alien cultures. But we have seen precisely zero. So, well, where are they?

As Hobbs said, we're pitifully pathetic in terms of actually going out into space and really doing field work. Which is fine, we've only been in space for sixty years and funding is low at best.

Do remember that at one point, people thought the primary reason there is life on Earth was because we had water, and we've confirmed "water" in several locations in our solar system.

Right here.

It might not be very obvious or encouraging, but we are getting closer to being able to finally find life, and I think our chances of finding it will increase exponentially the moment we can reliably send probes outside of our solar system that can relay information reliably back to Earth (or maybe even an outpost in our solar system, you never know what ingenious plan a space agency could come up with).

It's hard to be optimistic when it comes to space and humanity, though. We already have a garbage belt around the Earth and our space programs are gradually becoming less and less evident financially. As it stands now, the current most notable space agency I can think of is SpaceX. The ESA might become pretty notable in the next couple years, and the Canadian liberal party might be led by Canada's first astronaut soon. NASA will always be a pretty big letterhead thrown around in conversation, and they're still doing great things, but unless they get more nurturing from the government or from outside donors, their list of contributions to the space era will begin to shorten as time goes on if only because the cost of breaking new ground is too high compared to their funding.

 

[uppi]

Mmm... did i say they were the same thing? it was you who related causality with before/after. But yes, causality is very related with before/after time direction, the other way around being usually called retrocausality or backward-causality, which btw have been experimentally proved using quantum entangled particles, implying that quantum effects goes someway backwards in time, future events affecting past events.

No, quantum mechanics is not some magic fairy land, where everything including retrocausality is possible. Although a naive interpretation might suggest otherwise, there is no retrocausality in the experiments you are thinking of (probably the delayed choice quantum eraser). In these experiments the measurement events do not affect each other, therefore it does not matter in which order they are carried out. It just turns out, that the events are correlated. Explaining why they are correlated is what makes interpreting quantum mechanics so hard, but it is not that they affect each other.

And because they don't affect each other, you are not able to use this for FTL communication, or communication backwards in time or other violations of Special Relativity.

However a FTL drive as discussed in this thread would allow such things and thus a real violation of causality as we understand it.

 

[Thorgalaeg]

No, quantum mechanics is not some magic fairy land, where everything including retrocausality is possible. Although a naive interpretation might suggest otherwise, there is no retrocausality in the experiments you are thinking of (probably the delayed choice quantum eraser). In these experiments the measurement events do not affect each other, therefore it does not matter in which order they are carried out. It just turns out, that the events are correlated. Explaining why they are correlated is what makes interpreting quantum mechanics so hard, but it is not that they affect each other.

And because they don't affect each other, you are not able to use this for FTL communication, or communication backwards in time or other violations of Special Relativity.

However a FTL drive as discussed in this thread would allow such things and thus a real violation of causality as we understand it.

Of course never said you can use this for FTL communication, or communication backwards in time, in fact that goes backwards in time is "quantum information", not "classic information" which is a different thing, and this quantum information goes backward in the time. If there is retrocausation or not is a matter of interpretation.

 

[cav scout]

Well crap, it looks like North Korea is going to win a space race victory to Alpha Centauri since they have discovered some exotic matter.

 

[Birdjaguar]

But then again, I've read that negative numbers were nonsensical to scholars for a long time. How can you own a negative number of sheep? You can't, obviously. If you own -5 sheep, and someone gives you 3, you will have 3 sheep - not -2. But once it was accepted that numbers can be separated from the things they measure, it was not a big leap to accepting negative integers.

Perhaps it's the same thing here.

We can thank the Sumerians for that around 5000 years ago.

 

[Leoreth]

Sure, that's why it is an argument and not a proof. If you believe that the probability of intelligent life arising more than once across our galaxy is high, then you can conclude that there is something that prevents the aliens from reaching us.

Of course, if you think that the probability of life arising is extremely small, you can easily dismiss the argument.

Yeah, fair enough. I don't know if it was you who used the phrase but being "haunted" implied that there's some bona fide paradox here, and I spoke out against this notion (personally I don't think that FTL travel will be possible so that's a rather technical point from my side). And as Winner said, there's also the "intelligent life developing almost simultaneously so that their phase of space exploration can overlap" constraint.

Mmm... did i say they were the same thing? it was you who related causality with before/after. But yes, causality is very related with before/after time direction, the other way around being usually called retrocausality or backward-causality, which btw have been experimentally proved using quantum entangled particles, implying that quantum effects goes someway backwards in time, future events affecting past events.

Sorry, my post wasn't meant too critically, I just wanted to speak out against the "quantum physics = magic" implication I saw in your post.

For example, (I think) the Chinese had pretty much all the resources needed to discover and colonize the Americas, and yet they've never felt the need to, and so today the most spoken language of the USA is English

Don't forget that China sent Zheng He to trigger the Renaissance therefore they can still take the credit for everything Europe did.

It's hard to find anything on the subject, it could be a myth, but in general I think the (late) Chinese empires are excellent examples of wasted opportunities of dominating the world

Teleological history is annoying.

There's a big physical part to it too! We're, after all, talking about physical things like resources or the Earth's capacity to regulate its temperature.

Yeah, that's true. I only meant that the people who appeal to the "innovation will solve our problems" notion usually accept that AGW is real, therefore the physical questions don't matter as much. Their problem is more that they don't understand the economic and political incentives that are necessary to develop and implement these innovations, and the changes in social behavior that are necessary so that these innovations are actually sufficient to solve the problem.

Of course never said you can use this for FTL communication, or communication backwards in time, in fact that goes backwards in time is "quantum information", not "classic information" which is a different thing, and this quantum information goes backward in the time. If there is retrocausation or not is a matter of interpretation.

"Quantum information" is a concept I have never encountered before. Could you elaborate?

 

[El_Machinae]

The information state of entangled particles? The thing that prevents knowing both the position and momentum at the same time?

 

[Thorgalaeg]

@Leoreth:
Maybe my attempt to be funny was misleading. I dont meant quantum mechanics are magic. My intention was to point your previous comment about universe weirdness. What i mean is that quantum phenomena makes universe a really really weird place. The entanglement being a very good example of it. It is so weird most that experts have renounced to give any explanation we can relate to things as before after or causality. Of course there are diverse interpretations of the phenomena, the one i find less weird being the existence of retrocausality to the point in time when the EPR pair is separated, the other one which is even more against our conception of things is the concept of nonlocality of spacetime.

About "quantum information" it is a way to describe the hypothetical transference of quantum properties between two separated particles. Most physics will say there is nothing transferring between both entangled particles, but some physics says there is something very real, some sort of information moving backwards in time to the point both particles are separated and again to the future. It is a weird concept but everything here is extremely weird.

Anyway quantum mechanics dont enter in such things it simply says it happens.

 

[uppi]

"Quantum information" is a concept I have never encountered before. Could you elaborate?

Quantum information is the extension of classical information to the quantum regime. Bits which can have a value of 0 and 1 are extended to qubits which also can be a superposition of 0 and 1. Quantum information has some unusual properties, for example it can be teleported and do all kind of weird things. However, to access any information you have to convert it into classical information, so you lose all the quantum properties when you try to access it.

Quantum information processing is a hot topic in physics right now, and the goals range from quantum simulation and quantum computing to quantum communication (e.g. cryptography)

@Leoreth:
Maybe my attempt to be funny was misleading. I dont meant quantum mechanics are magic. My intention was to point your previous comment about universe weirdness. What i mean is that quantum phenomena makes universe a really really weird place. The entanglement being a very good example of it. It is so weird most that experts have renounced to give any explanation we can relate to things as before after or causality. Of course there are diverse interpretations of the phenomena, the one i find less weird being the existence of retrocausality to the point in time when the EPR pair is separated, the other one which is even more against our conception of things is the concept of nonlocality of spacetime.

With respect to retrocausality, a minority interpretation is quite a different thing from being experimentally proven.

 

[Birdjaguar]

From 2010:

Untangling the Quantum Entanglement Behind Photosynthesis

"This is the first study to show that entanglement, perhaps the most distinctive property of quantum mechanical systems, is present across an entire light harvesting complex," says Mohan Sarovar, a post-doctoral researcher under UC Berkeley chemistry professor Birgitta Whaley at the Berkeley Center for Quantum Information and Computation. "While there have been prior investigations of entanglement in toy systems that were motivated by biology, this is the first instance in which entanglement has been examined and quantified in a real biological system."

http://www.sciencedaily.com/releases/2010/05/100510151356.htm

I did not see any update refuting this.

 

[Leoreth]

Quantum information is the extension of classical information to the quantum regime. Bits which can have a value of 0 and 1 are extended to qubits which also can be a superposition of 0 and 1. Quantum information has some unusual properties, for example it can be teleported and do all kind of weird things. However, to access any information you have to convert it into classical information, so you lose all the quantum properties when you try to access it.

Quantum information processing is a hot topic in physics right now, and the goals range from quantum simulation and quantum computing to quantum communication (e.g. cryptography)

Okay, I was aware of these things. I expected something more related to Thorgalaeg's retrocausality hypothesis.

 

[El_Machinae]

From 2010:

Untangling the Quantum Entanglement Behind Photosynthesis


http://www.sciencedaily.com/releases/2010/05/100510151356.htm

I did not see any update refuting this.

Birds May Use Quantum Mechanics To Migrate South

it was known that cryptochrome electrons typically come in entangled pairs. Movement between the pairs occurs when magnetic fields cause the molecules' electrons to wobble and when sunlight knocks one of the electrons aside. The theory posits that a chemical reaction in response to the wayward electron's altered spin lets birds see magnetic fields in color.

 

[uppi]

From 2010:

Untangling the Quantum Entanglement Behind Photosynthesis


http://www.sciencedaily.com/releases/2010/05/100510151356.htm

I did not see any update refuting this.

This has actually been confirmed instead of being refuted.