The Speed of Light the fastest?

[leehoyle]

According to Science and Astronomical Science, the speed of light is the fastest in the known Universe, travelling at about 300,000 kilometers per second!<br />Let's say for argument's sake that the speed of light has been discovered in the last couple of centuries (lets say i.e. 100 to 200 years).<br />Then how come we know that i.e. a Galaxy is approx. 1 billion Ly (Lightyears) distant?

 

[Mee_n_Mac]

Just because light pokes along at 299,792,458 m/s doesn't mean we can see distant galaxies, it just means it takes a while for that light to get here. Hence when we look at them today (or tonight) we are seeing them as they were a long time ago. Just because we discovered a way to measure the speed of light "recently" doesn't mean that the light hasn't been travelling at that speed way before our discovery.<br /><br />To measure the distance to a galaxy we use the amount of redshift the light from it has undergone. Try Googling redshift and see what you come up with. <div class="Discussion_UserSignature"> <p>-----------------------------------------------------</p><p><font color="#ff0000">Ask not what your Forum Software can do do on you,</font></p><p><font color="#ff0000">Ask it to, please for the love of all that's Holy, <strong>STOP</strong> !</font></p> </div>

 

[silylene old]

The speed of tunneling is even faster - perhaps instantaneous. Quantum entanglements may also be instantaneous.<br /><br />from New Scientist, 17 August 2007 <br /><br /><blockquote><font class="small">In reply to:</font><hr /><p><b>Photons flout the light speed limit</b><br /><br />It's a speed record that is supposed to be impossible to break. Yet two physicists are now claiming they have propelled photons faster than the speed of light. This would be in direct violation of a key tenet of Einstein's special theory of relativity that states that nothing, under any circumstance, can exceed the speed of light.<br /><br />Günter Nimtz and Alfons Stahlhofen of the University of Koblenz, Germany, have been exploring a phenomenon in quantum optics called photon tunnelling, which occurs when a particle slips across an apparently uncrossable barrier. The pair say they have now tunnelled photons "instantaneously" across a barrier of various sizes, from a few millimetres up to a metre. Their conclusion is that the photons traverse the barrier much faster than the speed of light.<br /><br />To see how far they could make photons tunnel, Nimtz and Stahlhofen sandwiched two glass prisms together to make a cube 40 centimetres on its sides. Since photons tunnel most readily over distances comparable with their wavelength, the physicists used microwaves with a wavelength of 33 millimetres - long enough for large tunnelling distances yet still short enough that the photons' paths can be bent by the prism.<br /><br />As expected, the microwaves shone straight through the cube, and when the prisms were separated, the first prism reflected the microwaves (see Diagram). However, in accordance with theory, a few microwave photons also tunnelled across the gap separating the two prisms, continuing as if the prisms were still sandwiched together.<br /><br />Nimtz and Stahlhofen found that the reflected microwaves and the few microwaves that tunnelled through to the second prism both arrived at their re</p></blockquote> <div class="Discussion_UserSignature"> <div class="Discussion_UserSignature" align="center"><em><font color="#0000ff">- - - - - - - - - - - - - - - - - - - - - -</font></em> </div><div class="Discussion_UserSignature" align="center"><font color="#0000ff"><em>I really, really, really miss the "first unread post" function.</em></font> </div> </div>

 

[ashish27]

when you are looking at the night sky you are looking at history, something thats past a long time ago. a star you see in the sky may not exist at all, but you still see it because it used to exist a long time ago. <br />space is V A S T and light is like a ant in it.

 

[siarad]

Yes the speed of light can be exceeded but not the information or energy it carries.<br />In communication with submerged submarines waves travel faster than light but the information so reconstucted does not. Maybe they are looking at a similar effect