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Astronomer Discovers the Most Distant Stars Ever Observed From Earth
Cryolithic writes to tell us The Vancouver Sun is reporting that a University of B.C. astronomer recently used NASA's Hubble telescope to see a cluster of stars one billion light-years from Earth, the farthest stars ever observed from Earth. From the article: "That's interesting, he explains, because given that light travels at a finite speed -- 300,000 km a second -- the light emitted from the star cluster he and Kalirai saw was emitted one billion years ago. That means the cluster as it appeared to them two months ago was the way it looked one billion years ago. In other words, they were looking one billion years back in time."
1) The article begin with "A University of B.C. astronomer has discovered the farthest cluster of stars ever seen by a human eye " Wait, they don't use they eye, but the Hubble telescope in orbite with a "digicam" on it !
That's a perfectly accurate statement. They claim to have imaged the furthest individual cluster of stars. It is, therefore, the oldest cluster of stars ever seen by the human eye. Granted, it was probably on a computer after being exposed by a CCD, but it's still the furthest cluster we have ever individually observed.
No, not one bilion years back in time, but a billion years and two months.
What part of "the cluster as it appeared to them two months ago" don't you understand? They made the observation two months ago. Therefore, if the light took a billion years to get there, then the light was emitted a billion years ago. Regardless, this is just pointless pedantism.
This is obviouly the colors shift of the duppler effect,
Umm... no. This isn't "obviously" the duppler (sic) effect. Main Sequence stars redden as they age. The theory is that, a billion years ago, stars might be, on average, younger and hotter. So his supposition is that the cluster of stars will be, by and large, younger, bluer stars. Furthermore, the hubble constant is likely known at that distance, meaning the redshift can be largely compensated for before making conclusions regarding age, chemical makeup, and so forth.
Honestly, if you're gonna be a smart ass, the least you could do is research your claims first.
And I'm telling you, no, QE does not allow communication.
Thanks to the aforementioned result, Bob, the intended receiver of the signal, statistically can't tell that Alice's observation is what resulted in the waveform collapsing to specific state (versus it collapsing to some random state). The only way this can be done is by cloning the quantum state on Bob's end and then observing all the clones. If >50% collapse to a particular state, odds are, it was due to Alice's observation. Unforunately, there's a No Cloning Theorem which makes this impossible.
Please, if you want to counter what I'm saying, go educate yourself first. At this point, it's clear you're speaking from a position of ignorance.
No, I understand the concept perfectly. I just don't agree with it.
When you see something you are always seeing the past - what that object looked like when the light left it.No, you are seeing the present - what the object looks like after the light from the object has traveled to you. The light can be altered along the way by various means - some nearly imperceptible changes, some dramatic changes (like the light being blocked completely by an object passing through the light). So, you are not observing the same light that left, you are observing the light after it has been through a long journey.
In any case, you are observing the present, not the past. The present moment here looks different to the present moment there. no time travel has occured. The light is the only thing that has traveled.
Think of it this way... when you see our sun, you are seeing how it looked 8 minutes ago. If the sun blew up right now (ignoring all the other issues associated with the sun exploding), you wouldn't see the explosion for another 8 minutes even though it already happened.Yes, but you are still observing the present moment. Just because the light reaches you later doesn't mean you are observing the past. You are observing the present moment from your position. And if you wear sunglasses, for example, or a solar filter on a telescope, you are not observing the light as it left the sun - your sunglasses or telescope filter modifies the light on its journey.
... and then they built the supercollider.
It might not "age" - but its appearance is altered on the trip, for example by traveling through the Earth's atmosphere. So, you are not observing the same thing as a local observer would have.
To use your china analogy, it's more like, if someone came from china, bringing a photograph they took before leaving, then when they show it to you, the photograph does show what things were like those 12 (or whatever) hours ago.No it doesn't. This analogy really proves my point. Looking at a photo is nothing like looking at the person locally. A lot of information is lost and distorted. The photo is merely a representation of that person at that time, not the same thing as looking at that person with your eye.
This is the same as looking at light from the past; the light may have reached the present, but we're not looking at the light, we're looking at the image carried in the light, which is from the past. Disagree all you want, you'll find you're in the minority opinion.I don't really care about being in the minority position. I think it's more important to be precise, and also to ponder the philosophical questions, rather than rely on cool-sounding cliches like "looking into the past" which are only going to limit our thinking about how the universe exists. The image is in the present, and it doesn't look exactly the same as the local image would.
Most of the stuff we know about the universe was only known/believed by a few heretics in the minority at one point. Einstein wasn't a particularly popular guy in his early days. Once upon a time, the majority believed the Earth was flat, etc.
... and then they built the supercollider.