Speed of light maybe not as constant as we thought

posted by Jason Kottke Aug 07, 2002

A team of Australian scientists, led by Paul Davies (who has written several books on physics...I've read About Time) is theorising that electromagnetic waves may not have a constant speed as is commonly accepted. Predictably, the lead of this wire article focuses on Einstein being wrong...although Davies does a nice job in correcting that somewhat by saying, "it doesn't mean we just throw the books in the bin, because it's in the nature of scientific revolution that the old theories become incorporated in the new ones."

The most interesting bit of the discovery is the revelation that atoms from 12 billion years ago and present-day atoms are fundamentally different and that the difference seems to affect the speed of light. When we get some answers as to how that happened and if the process is reproducible, that'll be something. Mimicking nature in atom manipulation has provided us with new compounds, new elements, vast amounts of energy, and loads of new discoveries. Who knows what is possible if we can modify atoms to alter the speed of light.

As an enthusiastic arm-chair scientist, I'm waiting to hear about this from a slightly more rigorous source than Reuters before speculating further. (Does anyone have a subscription to the Nature site? I wouldn't mind getting a peek at the actual article in the August 8th issue... Update: Got a copy of the Nature article...thanks Danielle.)

Reader comments

steveAug 07, 2002 at 11:05PM

if you can find someone at UW-Madison, get their student ID and first four digits of their last name. then go to exproxy.library.wisc.edu and punch that info in.

Sachin nairAug 08, 2002 at 12:42AM

I could help you with the actual theory of relativity if you want, i have the whole book on my harddisk! If you can get hold of the actual piece, me being an arm chair scientist myself( to quote you) wouldn't mind a peek myself ;)

SteveAug 08, 2002 at 2:10AM

Why don't you try the horse's mouth(s): Tamara Davis


GregAug 08, 2002 at 6:33AM

I thought the article on slashdot was helpful in clarifying some technical things. This comment in particular was good because I had no idea what a fine structure constant was and how it related to the speed of light. Still, I can't help think that this isn't really a big deal; didn't we already know that the laws of physics were completely different in the immediate aftermath of the big bang?

barlowAug 08, 2002 at 6:49AM

When studying contrarians one time, I ran across a physicist named Setterfield who believes the light-speed constant has changed. Here is one of his articles: The Atomic Constants, Light, and Time. Perhaps it will be helpful. I'm not in a position to judge the guy's motives, but I often try to remain skeptical about contrarians since they seem to have an answer for every possible objection. Similarly, the guy who doesn't believe HIV causes AIDS is an interesting character study. He too has an answer for every objection.

Sachin nairAug 08, 2002 at 9:46AM

Actually to say the truth, i totally disagree when people say,"We thought speed of light is constant", for one thing, it should be velocity about which we should be talking about.

Velocity is speed with direction to boot! Now velocity is always measured relatively, withouht going into too many details.... The velocity of light is assumed to be constant due to to the high magnitude, the magnitude itself nullifies the directional part of velocity as any object compared on earth has negligibl speed!! Hence we assume whatever direction light assumes, its speed is constant! 3*19^8 m/s :)

Sachin nairAug 08, 2002 at 9:48AM

oops, a typo, it should be 3*10^8 metres per second.

GK NelsonAug 08, 2002 at 12:52PM

Would you be willing to share that Nature wealth? I'd sure like a more in-depth look at the subject.

And does this mean that, as light moves slower, time moves faster? No wonder everything speeds up as I get older.

StevenAug 08, 2002 at 12:53PM

Quite amusing that Jason's trying to be all intellectual. Struggle through Jason - is there any room in your brain for these theories and models with your gargantuan ego in there?

Steven GarrityAug 08, 2002 at 4:43PM

I too am an enthusiastic armchair scientist - more 'armchair' than 'scientist' - but enthusiastic none the less. A recommendation for Jason and other armoire academics: There is a regular CBC Radio (Canada's public radio) program called Quirks & Quarks hosted by Bob MacDonald that you may enjoy. In adition to being broacast on CBC Radio One, the show is available in RealAudio and in some cases MP3 format.

GK NelsonAug 08, 2002 at 7:42PM

While the cosmology article was fascinating, I found myself riveted by the New Guinea male frog caring for its young. Looks like I'll have to wander down to library tomorrow and see if I can't turn up this issue of Nature. Thanks for provoking my curiosity.

Jonathan BruderAug 08, 2002 at 9:24PM

[useful related media]:

CERN Summer Lecture Series Web Archive

Created for CERN summer intern students, these lectures cover a wide range of topics, including "Particle Physics (for non-physics students)." There are also more advanced lectures.

Real Video, most with synced web-copies of overhead transparencies. Bully for free education!

The Elegant Universe by Brian Greene

A great introduction (or fill-in-the-gaps) to the state of modern physics. The book is technical enough for the advanced armchair physicist; it is commonly applauded for the quality of the writing. Greene lucidly communicates complex ideas.

I don't necessarily recommend buying the book from the above link. It is worth purchasing, but save production energy and use your local library.

jordanAug 09, 2002 at 5:38PM

GK Nelson : "No wonder everything speeds up as I get older."

I have my own theory on that.

If you are 9 years old, the year to your tenth birthday will be 10% of your entire life -- thus it will feel a reasonably long time.

The year leading up to your 100th birthday however will constitute only 1% of your lifetime.

Seeing as the only way we can really perceive time is by measuring it against the length of 'time' we have been able to perceive it, a year (or a week, a day, a minute) seems shorter as we get older.

jordanAug 09, 2002 at 5:43PM

sachin :"Actually to say the truth, i totally disagree when people say,"We thought speed of light is constant", for one thing, it should be velocity about which we should be talking about. "

actually the speed of light (in a vacuum) is the thing that is constant. The velocity of light most certainly is not constant because velocity is a vector.

The direction of light (thus the velocity) can change as much as it wants, from mirror reflection to gravitational lensing, but the speed (the magnitude of the photon in any direction) is (according to the theory of relativity) an absolute constant (in a vacuum).

and here's some more parentheses ()(())))((()

jordanAug 09, 2002 at 5:46PM

OOPS! error in third paragraph of last post...

(the magnitude of the photon in any direction)

should be,

(the magnitude of the photon's velocity in any direction)

B Rajkumar DanielMar 14, 2003 at 12:11PM

Sure Guys,velocity of light is not constant. Supersonic jets fly and inside them sound travels with a constant velocity but the sound waves from ground never reaches them sothat the supersonics won't receive the sound from the ground.It means that using sound waves you never create a radar to detect the supersonic jets. Yes,same way when a body exceeds the velocity of light you never find it with light ,but they really exist.

DarioMay 08, 2003 at 11:04AM

What we all need to remember is that no law is forever,and I believe that gravity is a force within us,holding us down . Humans are said to use how much of their brains.? So what if we could expand our horizans and take in everything as a possibility, instead of limiting ourselves to what is said to be known?

This thread is closed to new comments. Thanks to everyone who responded.