Questions about the universe

UFOs, lost socks, discuss whatever you like here.

Moderators: Master_Kale, TNM Team

AEmer
Illuminati
Posts: 1490
Joined: Fri Jan 26, 2007 12:04 am

Re: Questions about the universe

Post by AEmer »

@ Jaedar

There's...a difference between communication and information? The fuck?

God damnit universe, go home, you're drunk.
G-Flex
Silhouette
Posts: 621
Joined: Mon Jul 11, 2011 10:16 pm

Re: Questions about the universe

Post by G-Flex »

There isn't, really. Classical information cannot be transmitted at superluminal speeds.
Cybernetic pig
Illuminati
Posts: 2284
Joined: Thu Mar 08, 2012 3:21 am

Re: Questions about the universe

Post by Cybernetic pig »

AEmer wrote: God damnit universe, go home, you're drunk.
Don't say that, everything will implode or be we'll all be sucked into a extra super massive black hole! (yes, super massive black hole is a scientific term. Not very imaginative).
DDL
Traditional Evil Scientist
Traditional Evil Scientist
Posts: 3791
Joined: Mon Oct 17, 2005 10:03 am

Re: Questions about the universe

Post by DDL »

I've always been a bit hazy on the whole superposition thing. In that ok, sure: wavefunctions, single-particle self interference etc fine, but really: is there any fundamental difference between two entangled particles that are collapsed and then taken vast distances apart, and two entangled particles that are taken vast distances apart and then collapsed?

Either way you're going to end up with "one up, one down, but you don't know till you look", and you can't influence the collapse other than to cause it by observation. All you find out by looking at your particle is "mine is -1/2, so theirs must be +1/2", information that is useless until you communicate it classically anyway.
AEmer
Illuminati
Posts: 1490
Joined: Fri Jan 26, 2007 12:04 am

Re: Questions about the universe

Post by AEmer »

Supermassive black holes are awesome btw. Nobody knows how they've come to be.

We know of black holes that are up to about 100 solar masses, and we know black holes that are millions of solar masses, but we don't know of many that are inbetween (though a couple have been observed, apparently).

Like, if they're just super fat normal black holes, why can't we find any that are kinda chubby?
User avatar
Jaedar
Illuminati
Posts: 3937
Joined: Fri Mar 20, 2009 3:01 pm
Location: Terra, Sweden, Uppsala.

Re: Questions about the universe

Post by Jaedar »

Maybe gravity is repulsive in certain densities :P

And from what I understand it the particles are both a superposition of say a spin up spin down state. It is only when you measure one of them that it becomes one or the other and this must simultaneously decide the state of the other particle. As such, the particles have communicated faster than light.

That's what I've read and been told anyway. Quantum physics is weird
"Delays are temporary; mediocrity is forever."
odio ergo sum
DDL
Traditional Evil Scientist
Traditional Evil Scientist
Posts: 3791
Joined: Mon Oct 17, 2005 10:03 am

Re: Questions about the universe

Post by DDL »

But they do so in a manner indistinguishable from a situation in which they had both been collapsed at the outset.

You can't make your particle spin up and thus theirs spin down, it's either up or down and theirs is down or up and you have no choice in the matter. It's more or less exactly the same as writing 1 and 0 on two pieces of paper, folding them up and shuffling them and handing them to two people who then fly 5 light years apart, then claiming that when person one unfolds his paper to reveal "0" that the paper must have magically communicated to the other paper to make it "1", which OMG IT IS.

It's kinda like...the decision to collapse the superposition has to be made, and it won't tell you anything useful, so the universe isn't really that fussed about WHEN that decision occurs.

Though of course, if you get into the actual physics of it you rapidly encounter people who argue that "instantaneous communication across light years" doesn't make sense, since locations separated by light years are not by definition even in the same frame of reference and you have to redefine what you mean by 'communicate' and then they talk about the copenhagen interpretation and bohmians and I kinda lose the will to live.

Mass effect must drive these people insane.
fantsu
UNATCO
Posts: 254
Joined: Thu Oct 29, 2009 11:51 pm

Re: Questions about the universe

Post by fantsu »

Light can travel faster than the speed of light in certain matter.
It was proven solid in 50's.
You guys read books that have been written before WW2 or what?

It just depends what speed of light is atm.
Bravery is not a function of firepower.
My "Deus Ex - Conspiracy" run on emulator
Alex Jacobson: They'll have you killed. They won't even blink an eye.
JC Denton: Neither did I.
User avatar
Jaedar
Illuminati
Posts: 3937
Joined: Fri Mar 20, 2009 3:01 pm
Location: Terra, Sweden, Uppsala.

Re: Questions about the universe

Post by Jaedar »

What I beleive you mean is that stuff can travel faster than the speed of light in that matter.

Nothing goes faster than c, the speed of light in vacuum. Some things go faster than the speed of light in matter c{index}. An example of this is neutrinos from nuclear decays which can move faster than photons in water, which is what produces the blue glow in nuclear waste pools. I've been told that this is caused by an effect similiar to a sonic boom.

People usually just say speed of light, and leave out the in vacuum part even if that's what they mean.
"Delays are temporary; mediocrity is forever."
odio ergo sum
DDL
Traditional Evil Scientist
Traditional Evil Scientist
Posts: 3791
Joined: Mon Oct 17, 2005 10:03 am

Re: Questions about the universe

Post by DDL »

Hell, fantsu: if you're being pendantic about it, I can travel faster than the speed of light (if the speed of light is that measured travelling through a bose-einstein condensate).

But since that's just fucking silly, everyone usually interprets it exactly as Jaedar states.
AEmer
Illuminati
Posts: 1490
Joined: Fri Jan 26, 2007 12:04 am

Re: Questions about the universe

Post by AEmer »

well the central conceit of mass effect is _right there in the name_ so they're kinda asking for annoyance.
User avatar
Grammatolatry
MJ12
Posts: 310
Joined: Tue Sep 08, 2009 12:09 pm
Location: New Zealand

Re: Questions about the universe

Post by Grammatolatry »

Hnng all your responses are so interesting.

The other day I was told there's a phenomenon whereby you actually influence matter simply by looking at it. Observation affects reality? So in theory, we're influencing these distant galaxies just by looking at them, even though we're so far away.

And and and! Does anyone have an opinion on Klein Bottles, and the ability to go faster than the speed of light by going 'around' it? (I read about those in a sci-fi novel by physicist, Catherine Asaro)
wink wonk
AEmer
Illuminati
Posts: 1490
Joined: Fri Jan 26, 2007 12:04 am

Re: Questions about the universe

Post by AEmer »

Actually, some real (science) nutters were suggesting that the entire universe were in a quantum waveform state, and that by making particular observations of it, we might collapse the waveform and thereby end all existence :D

But yes, fundamentally, observer and subject are entangled. It's, well that's probably not true in any kind of broad sense, but for now, it's the best model we have to describe a number of phenomena. I reckon it's probably similar to how newtonian mechanics were the best at describing a lot of physics for a long time, but how it turns out that newtonian mechanics are too general, and don't handle a lot of very important edge cases correctly.

So, we have observer-subject entanglement now; the idea that so long as you have yet to observe the state of something, it actually simultaneously inhabits all and none of the states possible at once. Once you observe it, you collapse it.

It's really very peculiar, but a number of important studies have been done on it, and they tend to show that if you're looking for a wave-pattern, that's the results you get, whereas if you look for particles, _they're_ the results you get...and that those two results can't exist simultaneously, but they in fact appear to exist under exactly the same circumstances except for the technique used for observation.

As for going faster than the speed of light via a klein bottle...yeah, well, nothing really ever goes faster than light speed. It's not even like a speed limit at this point; it's something super weird and entirely nonsensical.
User avatar
Jaedar
Illuminati
Posts: 3937
Joined: Fri Mar 20, 2009 3:01 pm
Location: Terra, Sweden, Uppsala.

Re: Questions about the universe

Post by Jaedar »

t=s/v,(lol nonrel :P ) so I think the idea is if we can't increase v we will have to decrease s by bending space time.
"Delays are temporary; mediocrity is forever."
odio ergo sum
User avatar
Jonas
Off Topic Productions
Off Topic Productions
Posts: 14224
Joined: Sat Apr 24, 2004 9:21 pm
Location: Hafnia

Re: Questions about the universe

Post by Jonas »

Urge to make... hard sci-fi game... increasing...
Jonas Wæver
Chief Poking Manager of TNM

I've made some videogames:
Expeditions: Rome
Expeditions: Viking
Expeditions: Conquistador
Clandestine
Post Reply