Speed of Light May Not Be Constant, Phycisists Say

Speed of Light May Not Be Constant, Phycisists Say

The speed of light is constant, or so textbooks say. But some scientists are exploring the possibility that this cosmic speed limit changes, a consequence of the nature of the vacuum of space.

The definition of the speed of light has some broader implications for fields such as cosmology and astronomy, which assume a stable velocity for light over time. For instance, the speed of light comes up when measuring the fine structure constant (alpha), which defines the strength of the electromagnetic force. And a varying light speed would change the strengths of molecular bonds and the density of nuclear matter itself.

A non-constant speed of light could mean that estimates of the size of the universe might be off. (Unfortunately, it won't necessarily mean we can travel faster than light, because the effects of physics theories such as relativity are a consequence of light's velocity). [10 Implications of Faster-Than-Light Travel]

I'm not really familiar with as many physics theories as I should be. I think this kind of research is fascinating because of the potential implications on our science and beliefs. I truly believe we've only scratched the surface and have so much more to discover about the world around us.



Speed of light may not be constant

Cool!

That is a very interesting discovery. S&F for making a thread about it. I read a similar article just a little while ago. Mankind does not know as much as we think we do. Your comment about just scratching the surface is good. This may show science that their assumptions about distance to other stars may be flawed. So many of the theories out there are reliant on the speed of light being a constant. There are a lot of theories about the rate of nuclear decay being a constant also, which was proven wrong recently, it seems that during a solar flare that the rate of decay is reduced a little.

Both of these discoveries show only miniscule changes but that is evident in this fishbowl of a solar system. I can't wait till data starts coming in from those satellites that are exiting the solar system, that data will be very important to science. It will either help to verify theories or make the theories need revisions. It could also put severe limitation on the use of some theories. I guess we will find out in a few years. I think at that point it will be necessary to send another satellite out of the heliosphere, but only after data comes in so we can properly equip the satellite with the right kind of sensors and technology. Sending one out now would be a waste of money, especially when our world economies are severely stressed.

reply to post by Cosmic911


According to textbooks c is a constant. But the value of c, by measurement, changes. I've read articles where the value of c can also be reduced to 34 m/s. The textbooks are wrong, c is mostly constant in certain conditions but it can be altered by natural phenomena and man-made equipment.

OK , I thought that these scientists were sent by god himself.

And I thought they just speak the truth.

And I can not accept that they have changed their comments.

Well, well.. something scientists have been so sure of being fact, turns out may be wrong.

reply to post by rickymouse

I can't wait till data starts coming in from those satellites that are exiting the solar system, that data will be very important to science. It will either help to verify theories or make the theories need revisions.

This will be a very exciting time! I think we'll come to learn much of what we believe as fact may not exactly add up. We are learning so much now. I can't wait to see what we discover in fifty years, or one hundred! I'm always disappointed when I think that I won't be around for the really cool discoveries.

This is quite interesting,rupert sheldrake tells of how it is not a constant, and had a fixed speed consigned to it in 1972 watch from 10.45 in

Originally posted by th3dudeabides
reply to post by Cosmic911

 

According to textbooks c is a constant. But the value of c, by measurement, changes. I've read articles where the value of c can also be reduced to 34 m/s. The textbooks are wrong, c is mostly constant in certain conditions but it can be altered by natural phenomena and man-made equipment.

Textbooks should say that the speed of light in a vacuum is constant. It only changes when traveling through matter, you will have read about how it changes in such circumstances as is taught to everyone in school. Only those who didn't go to, or didn't pay attention in school would not know this.

As for the original link, they are saying that "virtual" particles (their terms) slow down light just as normal particles do. Nothing amazing, and would make only tiny differences.

Well we know light changes speed in a vacuum because it bends through gravity
www.ehow.com...

Originally posted by Danbones
Well we know light changes speed in a vacuum because it bends through gravity
www.ehow.com...

The link you post talks nothing about gravity. I'm guessing you're talking about gravitational lenses, in which case light still travels at the same speed, it is spacetime that is bent. This is part of general relativity.

reply to post by mideast


Science is founded on uncertainty. Each time we learn something new and surprising, the astonishment comes with the realization that we were wrong before. History is chock full of Quotes from the greatest scientist of their time saying something could not be done only to be proven wrong. No God or Gods just people trying to make the world a better place.... or doing directed research on a topic for money because they are thought qualified.

It wasn't to long ago some of the greatest minds of their time spent months and years trying to figure out how many angels could dance on the head of a pin. These were the theorist of there day; due to no physical evidence and countless days and years of brain power wasted during the renaissance they discarded the research and moved on to more physical based science.

Science advances by proven results; theorist tell us why we got the results however that is where the process breaks down on occasion. Sometimes the theory precedes the science and points the way to scientific endeavors. The why, when, where, cause and effect is what science is about, IMO ....

Sometimes there are several ways to arrive at a particular process or conclusion when the field of research is narrow. Look at wave and particle light waves. Both function correctly in their own right.

A Mechanical Engineer would be at a loss when working in an Electrical Engineers field etc etc

Originally posted by th3dudeabides
reply to post by Cosmic911

 

According to textbooks c is a constant. But the value of c, by measurement, changes. I've read articles where the value of c can also be reduced to 34 m/s. The textbooks are wrong, c is mostly constant in certain conditions but it can be altered by natural phenomena and man-made equipment.

It's not quite this simple.

In physics 'c' is the constant in the Lorentz transformation which was asserted by Einstein---correctly---as being fundamental to all physical laws. Relativity is, at its core, asserting that all physical laws obey certain symmetry and transformation properties. There have been no experimentally verified counterexamples.

The point of the paper is that the quantum electrodynamics can result in macroscopic propagation of light in high intensity (large distances) might have a collective effect due to vacuum effects.

In quantum field theory it is very common to have a different 'bare' parameter compared to an effective parameter when all interactions are taken into account.

In classical physics the group velocity of propagation of a macroscopic pulse is 'c' exactly. Perhaps there is a quantum mechanical correction. That's what this issue is still about.

The speed of electromagnetic interactions between particles is exactly 'c' still---what changes is the meaning of the "speed of light" as the latter implies a physical scenario (e.g. over astrophysical distances) which results in additional quantum mechanical effects.

It's just like classical dielectric permittivity --- speed of light macroscopically is altered by real atoms---and there may be a much smaller correction from quantum mechanical virtual particles.

The core of Einsteinian relativity remains untouched.

Originally posted by mideast
OK , I thought that these scientists were sent by god himself.

And I thought they just speak the truth.

And I can not accept that they have changed their comments.

Perhaps a declaration from a god, a prophet or a channeler of aliens would be more acceptable?

Declared truth is so much easier, after all, than study.

At any rate, if you read the parts the OP left out, the effect is so small as to be nearly unmeasurable. If it exists. And if it does, well, it's the same thing that causes light to be slower in a material. You DID know that light is slower in, say, glass, than a vacuum?

reply to post by Subterranean13

Nothing amazing, and would make only tiny differences.

Well the size of the differences will depend on the size of the medium that the light will travel and its characteristic. In astronomical scales this may not be such a tiny issue.

Originally posted by Panic2k11
reply to post by Subterranean13

 

Nothing amazing, and would make only tiny differences.

Well the size of the differences will depend on the size of the medium that the light will travel and its characteristic. In astronomical scales this may not be such a tiny issue.

In astronomical scales, it probably averages out to no effect at all, other than to appear as noise. It isn't a bias in any one direction, fast or slow, it's random. If it exists.

My personal viewpoint on this is that the medium by which light is transmited is space-time itself. Just as the speed of sound travels through water differently depending on what state it's in. It follows that light speed would alter depending on what state the space-time was in.

I've always maintained this view, so it's interesting to read such an article.

Peace,

Korg.

The speed of light is not constant.

The speed of light is not the speed limit of the universe.

The speed of light is simply the speed of a photon

Sorry Einstein....

reply to post by Bedlam

In astronomical scales, it probably averages out to no effect at all, other than to appear as noise. It isn't a bias in any one direction, fast or slow, it's random. If it exists

Humm ?!? The effect in the speed is always down (it will not accelerate), no variance up. The randomness of the effect will only make that the average will be constant from any one direction, but the dimension of the effect will not be tiny at huge distances...

Originally posted by Subterranean13

Originally posted by Danbones
Well we know light changes speed in a vacuum because it bends through gravity
www.ehow.com...

The link you post talks nothing about gravity. I'm guessing you're talking about gravitational lenses, in which case light still travels at the same speed, it is spacetime that is bent. This is part of general relativity.

it bends around the moon which is in a vacuum
and to bend it has to slow down relative to the observer
as it says at the link