Speed of Light Decaying over time?

[Truth_Seeker]

Hello to you all,

 

Is anyone familiar with this view? That the speed of light has slowed, perhaps up to 10-30% within the past 2000 years?

 

Most everything I have found on the web indicates that this theory is not embraced by many. Yet, I do know some people who hold to it, so perhaps it is still an ongoing possibility?

 

I admit I have only a surface knowledge of physics, so I was wondering if anyone who actually has an understanding of the field views this as a credible theory.

 

Am I correct in that someone supporting the view that lightspeed is decaying would have to reject the notion that the universe is expanding?

[[Tycho?]]

I've heard of it. But no it isn't embraced widely, I dont really know much about it, or if there is any evidence to support it.

 

I dont think you'd have to reject the notion that the universe is expanding. You would probably disagree on the age of the universe and how quickly it is expanding, but it should still come out as expanding regardless.

[Mokele]

I've heard quite a bit about it, and I'll sumarize shortly: It's creationist bollocks. The guy took historical measures of lightspeed (back when more primitive equipment induced more error and had less precision anyway) compared those to the present, and artificially extrapolated backwards. He even deliberately falsified the already-worthless data so that he'd show the universe was only 10,000 years old. He also arbitrarily set a date in the past as being the time when light magically decided to stop slowing down, so that his theory could never be tested.

 

For the more thorough debunking and ridiculing that this work so richly deserves, see:

http://www.talkorigins.org/faqs/c-decay.html

 

The short answer: More creationist idiocy.

 

Mokele

[JPQuiceno]

Thanks Mokele, thats exactly what I thought. He used ancient data based off some cave man techniques, and then compared them to the present data.

 

Funny how some man with a big mouth and off-target data can get so much attention. Heh, everyone wants their 15 minutes eh?

[Truth_Seeker]

Thanks for the information, and thanks for that link as well. There are some links on that webpage that definitely look worth checking out.

 

I had heard about the Norman and Setterfield hypothesis from the 80s, which that direct webpage talks about, and basically how their assertions and data hold no validity at all. But, from what I could see there seems to be a resurfacing of interest in this theory (within the last 3 years or so?), and I didn't know if maybe there was some new evidence in support of it or if it was now being taken more seriously for some reason. Or if it was the same old hypothesis with the same old data that they were still talking about.

[Sayonara]

It's because space is getting stickier.

[darkkazier]

now, i am confused, i thought light was the ultimate measurment of speed, and nothing could go faster than light period? I read an article on newscientist . com where some physists slowed down a beam of light to 30 mph. Would that mean that if i drove my car and raced the beam of light i could not accelerate up to 30mph?

[Daecon]

Nothing can go faster than light at it's natural speed.

 

That one beam of light just wasn't going at "light speed". simple as that.

[darkkazier]

Wait a minute, i thought that quantum tunneling was faster than light? If it's true then shouldn't we stop sayign that traveling faster than light is impossible?

[Daecon]

I think that quantumn tunneling isn't through normal space... hence the "tunneling"?

 

Like in Star Trek (et al) where they go faster than light by travelling through "sub-space"?

[swansont]

now, i am confused, i thought light was the ultimate measurment of speed, and nothing could go faster than light period? I read an article on newscientist . com where some physists slowed down a beam of light to 30 mph. Would that mean that if i drove my car and raced the beam of light i could not accelerate up to 30mph?

 

The speed limit is c, which is the speed of light in a vacuum. You can go faster than light, just not faster than c, because the propagation speed decreases in a medium with index >1, so that v = c/n.

[darkkazier]

Ahh, i got it, thanks a lot