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i think the speed of light is max
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Gundolf Jahn Send message Joined: 19 Sep 00 Posts: 3184 Credit: 446,358 RAC: 0 |
Someone has been reading some Stephen Hawking. 8-] Yes, and Roger Penrose, but that's been quite a while. The most I know about that topic, I've read in Spektrum der Wissenschaft, the German branch of Scientific American. Gruß, Gundolf |
Ptar Send message Joined: 17 May 99 Posts: 171 Credit: 19,598,238 RAC: 16 |
Doesn't quantum entanglement imply that information (in this case polarity of protons) can be 'transmitted' at a rate faster than light speed - since the polarity change of entangled protons (appears) to occur simultaneously, with no 'speed-of-light' timelag? |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
This is why Einstein called it "spooky action at distance". The project QuantumFIRE debates this subject, if you are interested. Incidentally, it is never out of work. Tullio |
Gundolf Jahn Send message Joined: 19 Sep 00 Posts: 3184 Credit: 446,358 RAC: 0 |
I think it was the polarity of photons, not protons. With protons I'd expect a property like spin used for entanglement. Some interpretations of the effect imply that no information transfer faster than light is possible that way nevertheless(http://en.wikipedia.org/wiki/Quantum_entanglement#Other_Interpretations). What surprised me was to find particle-pair communication and Higgs-transfers (for matter transport) featured in a science-fiction novel from 1999 (Bios by Robert Charles). Gruß, Gundolf |
Ptar Send message Joined: 17 May 99 Posts: 171 Credit: 19,598,238 RAC: 16 |
Sorry to all. Photons. Photons. My fingers want to type something different, as above. @Tullio - thanks for the suggestion. QuantumFire is news to me and the premise looks interesting. (I didn't do QMC because it was chem project). Cheers! |
Ptar Send message Joined: 17 May 99 Posts: 171 Credit: 19,598,238 RAC: 16 |
Another way to 'beat the speed of light' (on a technicality): I don't recall the details of this experiment, but some research group in the US measured real-velocities of laser-light propogation at faster than 'light speed'. Turns out the front edge of the light 'wave' could reach a detector at "supra-light-speed", while the 'main body' of the light wave would arrive at "light speed" and the trailing portion could arrive at sub-light-speed. The velocities calculated were just over, at, and just under light speed respectively. This was exciting at the time (supra-light speed documented!) but then became boring because the effect was shown to be consistent with known physical law and didn't 'actually' defeat the 'light speed' limit. A quick google search and I only find one reference to it in a Grade 9-12 discussion in New Jersey. Sheeesh; talk about being behind the times. My point with this, and with quantum entanglement above: although nothing is currently known that shows faster-than-light is possible, there are indications out there that perhaps something **might** be able to do so. If only we have the instinct to test for it, and the wit to discover it. |
tullio Send message Joined: 9 Apr 04 Posts: 8797 Credit: 2,930,782 RAC: 1 |
I must fish in my memory. For a wave packet you can define both a group velocity and a phase velocity. Their product is c^2 (in a vacuum). But only group velocity carries energy/momentum, phase velocity does not. So group velocity cannot be greater than c, phase velocity can, But this does not violate relativity. Tullio |
platium Send message Joined: 5 Jul 10 Posts: 212 Credit: 262,426 RAC: 0 |
we have a goverment like that if they do not like it they bypass it so way |
platium Send message Joined: 5 Jul 10 Posts: 212 Credit: 262,426 RAC: 0 |
i maybe wrong light speed maybe pass |
SciManStev Send message Joined: 20 Jun 99 Posts: 6653 Credit: 121,090,076 RAC: 0 |
During inflation, space itself expanded, and nothing limits this expansion to the speed of light (there's no acceleration of masses). I was sitting back for a while, as tullio has much greater knowledge than I do. We see stars only at this point in time because they haven't used up their fuel yet. There will be a time when the only source of light will be from red dwarf stars. The following link does a good job of describing where we were, where we are, and where we are going. You can use the interactive option to show much of that. http://www.pbs.org/wgbh/nova/origins/universe.html This may not be completely correct, but it gives a good rough idea. Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 30692 Credit: 53,134,872 RAC: 32 |
So what is the universe expanding into? The universe or the observable universe? The observable universe is expanding into the universe. The universe is infinite, just a lot of it isn't aware some kook dumped some energy into a backwoods spot a few billon years ago. |
SciManStev Send message Joined: 20 Jun 99 Posts: 6653 Credit: 121,090,076 RAC: 0 |
So what is the universe expanding into? Einstein once said that if you keep going in a straight line, you will end up where you started. He was stating that the universe is curved, or at least space was. Here is a picture of what the universe looks like, as it has an age of 13.7 billion years. http://www.atlasoftheuniverse.com/ Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
William Rothamel Send message Joined: 25 Oct 06 Posts: 3756 Credit: 1,999,735 RAC: 4 |
Two things to consider. The far reaches of the universe are, in fact, receding from us at a speed faster than the speed of light. That is why in a universe only 15 Billion years old it can have a diameter exceeding 150 Billion Light years. Gravity is understood --as given by the General Theory of Relativity--To be a warpage of space in the presence of mass. The universe is finite and unbounded . Like the surface of a basketball. A two dimensional surface extending into three dimensional Euclidean space and if you blew it up with more air it's surface would expand. So we are expanding into three dimensional space which is created by the expansion of the universe. |
SciManStev Send message Joined: 20 Jun 99 Posts: 6653 Credit: 121,090,076 RAC: 0 |
Two things to consider. The far reaches of the universe are, in fact, receding from us at a speed faster than the speed of light. That is why in a universe only 15 Billion years old it can have a diameter exceeding 150 Billion Light years. Thank you! I was hoping you would chime in. :) Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 65779 Credit: 55,293,173 RAC: 49 |
So what is the universe expanding into? Hi Steve, According to some nuts, They insist that the world everything else is no older than 6,014 years(the 4004 BC crowd), But We all know better than some screw balls. The T1 Trust, PRR T1 Class 4-4-4-4 #5550, 1 of America's First HST's |
SciManStev Send message Joined: 20 Jun 99 Posts: 6653 Credit: 121,090,076 RAC: 0 |
The statement that you mentioned about the world only being that old is one of the most incorrect statements ever made in modern times. The logic for such a statement completely escapes me, yet I realize that many actually believe it. Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
Bill Walker Send message Joined: 4 Sep 99 Posts: 3868 Credit: 2,697,267 RAC: 0 |
It was worked out by a British clergyman, I think in the early 19th century. He drew up a linage chart back to Adam and Eve based on the Bible, assigned an age to everybody, and added it all up. Not defending him or his calcs, just offering a bit of historical trivia. |
Ptar Send message Joined: 17 May 99 Posts: 171 Credit: 19,598,238 RAC: 16 |
[quote] It was worked out by a British clergyman, I think in the early 19th century. He drew up a linage chart back to Adam and Eve based on the Bible, assigned an age to everybody, and added it all up. Not defending him or his calcs, just offering a bit of historical trivia. James Ussher was an Irish clergyman; he published his calculated date of "creation" in the mid-1600's. Worked it out to be on a Sunday, October 23, 4004 BC. (There is a good wiki article 'natch.) In 2nd year univ I was taught a geology course by a scientist who believed the 4004 BC date; so some of the lecture time was taken up with how the calculation was performed. It was bemusing, to put it mildly. And then I would go next door to my "Fundamentals of Logic" course ... . |
Gundolf Jahn Send message Joined: 19 Sep 00 Posts: 3184 Credit: 446,358 RAC: 0 |
Two things to consider. The far reaches of the universe are, in fact, receding from us at a speed faster than the speed of light. That is why in a universe only 15 Billion years old it can have a diameter exceeding 150 Billion Light years. The red shift caused by the expanding of the universe has (almost) nothing to do with Doppler shift. Gruß, Gundolf Computer sind nicht alles im Leben. (Kleiner Scherz) SETI@home classic workunits 3,758 SETI@home classic CPU time 66,520 hours |
SciManStev Send message Joined: 20 Jun 99 Posts: 6653 Credit: 121,090,076 RAC: 0 |
There is a new series on the Science channel called Through the Wormhole, narrated by Morgan Freeman. It explained the latest theories on expansion, M-Theory, and even SETI. I saw two episodes last night, and I highly recommend it. Steve Warning, addicted to SETI crunching! Crunching as a member of GPU Users Group. GPUUG Website |
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