Linked Questions

4
votes
2answers
870 views

Space expanding, or light slowing down? [duplicate]

This question seems a lot like one of those "Phylosoraptor" memes all over the Internet, and it might be very silly, but I've been thinking about this for a while. Is it possible that space is not ...
1
vote
1answer
185 views

Speed of light in vacuum - is it really a constant and what is the accurate value? [duplicate]

Let's suppose that the speed of light would not be a constant but a function of something. As is quite clear now, universe is expanding exponentially. If the speed of light would actually be a ...
-1
votes
1answer
98 views

Rebuttals for variable speed of light? [duplicate]

I'm finding a lot of popular articles about the "exciting" possibility that the speed of light might be changing. However, I'm having no luck finding a good rebuttal. My general understanding is that ...
0
votes
1answer
58 views

Is it possible that the speed of light has changed since the beginning of the universe? [duplicate]

Asking purely out of curiosity: Is there any research or publication in Modern Physics that considers the possibility that the speed of light has changed since the Big Bang, and not remained constant ...
48
votes
2answers
6k views

2002 research: speed of light slowing down?

Back in 2002 there was some research published hinting that $c$ may have been faster at some distant point. It was based on measurements of the fine-structure constant, $$ \alpha = \frac1{4\pi\...
19
votes
2answers
4k views

Why do universal constants have the values they do?

This is meant to be a generic question of the type that we get repeatedly on this site, in different versions: The origin of the value of speed of light The gravitational constant G theoretically? ...
12
votes
2answers
6k views

The famous drop of $c$

In this (in my opinion) intriguing speech, Rupert Sheldrake tells the story of the drop in the measured value of $c$ between 1928 and 1945. When he goes to visit the Head of Metrology of the Physics ...
5
votes
2answers
1k views

How can I explain the scientific basis of the constant speed of light to a $c$-decay proponent?

This Phys.SE question asks why and how the speed of light is constant. I would like to ask a related, almost converse question: Given that the speed of light is constant, how could I explain to a ...
7
votes
4answers
1k views

Can the cosmological constant change with time?

This post is a specialization of the post: Can the proportion of dark energy change? Can the cosmological constant change with time? If so, is there a measurement of this evolution up to now, and ...
3
votes
3answers
528 views

Does Universe really expand? What if the speed of light is decreasing instead?

What I am understanding on the articles I have read is that the conclusion "universe expands" depends on the assumption "the speed of light is constant". Of course it's not the major factor but what ...
1
vote
3answers
157 views

What tells us the speed of light is constant in another galaxy?

I've read, and I hope to keep reading, so please send me all your links, and I apologize in advance if this is a duplicate, or non-mainstream physics question as the speed of light is widely accepted ...
1
vote
2answers
549 views

Red Shift and Light Speed

I read several questions/answers about red shift on this web site, but there is something I still don't understand. Why is red-shift considered to be the effect of expanding space-time, why it could ...
2
votes
1answer
77 views

Can speed of light vary from one to another region in universe?

I think speed of light and property of spacetime and gravity are interrelated. So is it possible that the speed of light in the past universe was more/less compared to now?, Does the property of ...
1
vote
1answer
93 views

How much impact would it make in science if the speed of light is discovered to be variable? [closed]

So if such a thing happens, how would it alter current physics?