Posted on 07/27/2011 2:26:16 PM PDT by SeekAndFind
Physicists have confirmed the ultimate speed limit for the packets of light called photons - making time travel even less likely than thought.
The speed of light in vacuum is the Universe's ultimate speed limit, but experiments in recent years suggested that single photons might beat it.
If they could, theory allows for the prospect of time travel.
Now, a paper in Physical Review Letters shows that individual photons too are limited to the vacuum speed limit.
That means that photons maintain the principle of causality laid out in Einstein's theory of special relativity - that is, an event's effect cannot precede its cause by travelling faster than light. It is violation of this causality that would, in principle, permit time travel.
While the limit in vacuum is a fixed number - some 300,000km per second - the speed of light can vary widely in different materials.
These differences explain everything from why a straw looks bent in a glass of water to experiments in cold gases of atoms in which light's speed is actively manipulated.
Some of those experiments showed "superluminal" behaviour, in which photons travelled faster than the speed of light in a given medium.
It remained, however, to determine whether or not individual photons could exceed the vacuum limit.
(Excerpt) Read more at bbc.co.uk ...
Well, light is a particle if you're looking for a particle, but it's a wave if you're looking for a wave.
Light is also affected by gravity - but we're not really sure what gravity is......
I hear they don't weigh much either.
“Time is nature’s way of keeping everything from happening at once” Albert Einstein
I read somewhere that these these particular scientists are governmen funded Chi-Coms, so I won’t abandon work on my flux capacitor just yet...
That is very definitive, thanks.
:p
It is a round about, to prove you can travel into the future you must prove the future has already taken place hence you would be traveling in the past.
Meh....Just wait until Congress increases the Univeral Speed Limit! LOL...Poof Time Travel...
Always wondered about that! Must have built-in superluminal telepathic cell phones...lol
RE: I read somewhere that these these particular scientists are governmen funded Chi-Coms,
Well this research just so happens to have been conducted in HONGKONG (now under China of course ).
See here :
EXCERPT:
A team of scientists says it’s officially time to leave the idea of time travel in the past.
In a study released by the Hong Kong University of Science and Technology, a team of physicists claims to have proved that a single photon “obeys the traffic law of the universe,” and that as Albert Einstein theorized, nothing in the universe can travel faster than the speed of light, Discovery News reported.
The findings of the study, published in the U.S. scientific journal Physical Review Letters, contradict the idea that quanta of light can move backward through time. In other words, moving through time is a one-way ticket.
I am posting this at 6:49 EDT.
Two more words: tachyon movement
Once again, you have proved that FR time is way ahead of you.
There's a way out of the box reference frame explanation for it, basically our reference frame with the dimensions of time and distance doesn't exist for photons at the speed of light (Entangled photons are never really apart in their reference frame), but I get rocks thrown at me when I mention it :^)
Perhaps more in keeping with the original post:
Time flies like an arrow. Fruit flies like a banana.
Cheers!
Okay, let me see if I get wht your saying. Since the Photon pair are at the speed of light, time doesnt exist and therefore motion doesnt exist? Since by definition motion (distance) is dx/dt.
Like I said way out of the box and frowned upon :^).
Seems like a logical conclusion to relativity to me. It is a bit of a noodle-baker since it is tricky to be in the "shoes" of a photon with no apparent time or motion. They would appear to exist then not exist. Going nowhere in zero time. Photons dont need wrist watches! :o)
“Yea, yea right, but what about 2 entangled photons able to communicate their spin state instantaneously irregardless of their distance? “
Yep. Definitely puts the kibosh on the theory that everything that happens in universe must go slower than “c”. Just because photons and electromagnetic-waves may not be able to travel faster than “c”, that does not mean that everything that happens in the universe must go slower than “c”.
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