Could we say that velocity of light does not remain constant in time,

[Ignition]

Could we say that velocity of light does not remain constant in time, but that it vary in time with the expanding Universe?
It could be different, less than c, in my opertations, but it is not according the relativity.

 

[malawi_glenn]

Google "light speed as function of time" and you'll find many crackpot sites..

Paradigm of real physics is that the speed of light is a constant.

 

[tiny-tim]

Magueijo etc

Could we say that velocity of light does not remain constant in time, but that it vary in time with the expanding Universe?
It could be different, less than c, in my opertations, but it is not according the relativity.

Hi Ignition!

Lots of PF threads on this (which I haven't read! )

Do a google search for magueijo +"speed of light" site:physicsforums.com.

For example, https://www.physicsforums.com/archive/index.php/t-150818.html":

Variable speed of light theories are actually a very old idea; the VSL proposal of Joao Magueijo is only the most recent contender.

 

[Ignition]

But the first site i have seen says that c has decreased in past 300 years.

 

[tiny-tim]

what site??

But the first site i have seen says that c has decreased in past 300 years.

erm … you need to specify the url.

 

[Ignition]

It is http://ldolphin.org/constc.shtml
http://ldolphin.org/constc.shtml

 

[Ignition]

So the velocity of light will be zero in the end?
Excuse me, but I can' t speak english very well.

 

[cristo]

It is http://ldolphin.org/constc.shtml
http://ldolphin.org/constc.shtml

I wouldn't trust much that you read there, since it appears to be a creationist site. There are, as others have said before, variable speed of light theories, but they are not currently part of the agreed on model of cosmology. That's not to say they shouldn't be taken seriously, though. Try reading the link that tiny-tim gave you, specifically the post by Chris Hillman.

 

[tiny-tim]

Creation Research Society Quarterly!

hmm …

PAPER DELIVERED AT PITTSBURGH CONFERENCE ON CREATIONISM … Summer 1994

The http://www.ldolphin.org/cdkalan.html" begins:

INTRODUCTION

In 1987 Setterfield published his monograph Atomic Constants, Light and Time[19] which raised again the question of the constancy of c. Since then there have been no less than 17 articles in the Creation Research Society Quarterly and 12 articles in the Creation Ex Nihilo Technical Journal debating this issue. Authors have used various statistical techniques including run tests, regression lines, weighted regression lines and distribution tests. One important claim made by Setterfield is that the decreasing c hypothesis explains how the transit time of light from galaxies billions of light years away takes only thousands of years.

Wow!

No less than 17 articles in the Creation Research Society Quarterly

and

12 articles in the Creation Ex Nihilo Technical Journal!

I'm impressed! ​

 

[Ignition]

It is a not trust site.

 

[cristo]

Since the article clearly doesn't conform to PF guidelines, I'm going to lock this thread to prevent further discussion. If anyone wishes to talk about published VSL theories, then please feel free to open another thread.