# So it turns out the speed of light might not be constant after all

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#1 Posted by LauraPortinari (67 posts) -
Our God is a particle???. XD http://www.catholic.org/technology/story.php?id=50261 The current laws of physics says that light travels approximately 186,000 miles per second in a vacuum. That's been a handy fact that has allowed scientists to calculate the distances to faraway objects and to conduct other research with great accuracy. However, that measurement assumes that space is a vacuum. It isn't. Space is filled with tiny subatomic particles which although extremely diffuse, can theoretically slow down light just a tiny bit. How tiny? About 50 attoseconds per square meter of crossed vacuum. An attosecond is a one quintillionth (10^-18) of a second. An attosecond is to a second what a real second of time is to 31.71 billion years. So that's not a lot of egg on the face of physics. Still, over very great distances light from distant objects could be slowed just slightly. That slowing isn't enough to impact any currently accepted theories regarding physics, but it still suggests that even the most reliable of yardsticks may be variable after all. Very minor changes to currently accepted understandings may be required, but since the changes are so slight they might not be significant, and therefore unworthy of much modification. The greatest change might be to textbooks, which will need to add a caveat that the speed of light is constant, only in a true vacuum-which space isn't. The findings must still survive peer review before that happens.
#2 Posted by Rattlesnake_8 (18452 posts) -
Interesting.
#3 Posted by DirigiblePlums (142 posts) -
[QUOTE="LauraPortinari"]Our God is a particle???. XD http://www.catholic.org/technology/story.php?id=50261 The current laws of physics says that light travels approximately 186,000 miles per second in a vacuum. That's been a handy fact that has allowed scientists to calculate the distances to faraway objects and to conduct other research with great accuracy. However, that measurement assumes that space is a vacuum. It isn't. Space is filled with tiny subatomic particles which although extremely diffuse, can theoretically slow down light just a tiny bit. How tiny? About 50 attoseconds per square meter of crossed vacuum. An attosecond is a one quintillionth (10^-18) of a second. An attosecond is to a second what a real second of time is to 31.71 billion years. So that's not a lot of egg on the face of physics. Still, over very great distances light from distant objects could be slowed just slightly. That slowing isn't enough to impact any currently accepted theories regarding physics, but it still suggests that even the most reliable of yardsticks may be variable after all. Very minor changes to currently accepted understandings may be required, but since the changes are so slight they might not be significant, and therefore unworthy of much modification. The greatest change might be to textbooks, which will need to add a caveat that the speed of light is constant, only in a true vacuum-which space isn't. The findings must still survive peer review before that happens.

Ah, the most useless facts are also the most important.
#4 Posted by DirigiblePlums (142 posts) -
[QUOTE="LauraPortinari"]Our God is a particle???. XD http://www.catholic.org/technology/story.php?id=50261 The current laws of physics says that light travels approximately 186,000 miles per second in a vacuum. That's been a handy fact that has allowed scientists to calculate the distances to faraway objects and to conduct other research with great accuracy. However, that measurement assumes that space is a vacuum. It isn't. Space is filled with tiny subatomic particles which although extremely diffuse, can theoretically slow down light just a tiny bit. How tiny? About 50 attoseconds per square meter of crossed vacuum. An attosecond is a one quintillionth (10^-18) of a second. An attosecond is to a second what a real second of time is to 31.71 billion years. So that's not a lot of egg on the face of physics. Still, over very great distances light from distant objects could be slowed just slightly. That slowing isn't enough to impact any currently accepted theories regarding physics, but it still suggests that even the most reliable of yardsticks may be variable after all. Very minor changes to currently accepted understandings may be required, but since the changes are so slight they might not be significant, and therefore unworthy of much modification. The greatest change might be to textbooks, which will need to add a caveat that the speed of light is constant, only in a true vacuum-which space isn't. The findings must still survive peer review before that happens.

But I don't quite understand. How could scientists overlook something as obvious as "space isn't a vacuumn."
#5 Posted by MannyDelgado (1187 posts) -

The greatest change might be to textbooks, which will need to add a caveat that the speed of light is constant, only in a true vacuum-which space isn't. The findings must still survive peer review before that happens. LauraPortinari
Silly. This is already a very well-known fact

Popular science reporting remains as sh*t as ever

#6 Posted by GOGOGOGURT (4470 posts) -

Light moves at different speeds through different substances.

Where have you been the last 100 years?

#7 Posted by kuraimen (28078 posts) -
http://www.catholic.org/technology/story.php?id=50261 http://www.catholic.org/technology http://www.catholic.org catholic
#8 Posted by br0kenrabbit (15094 posts) -

It's NOT slowing down the speed of light, it's slowing down the APPARENT speed.

Lets take a glass window for example. You can see through it, so that means light passes unimpeded through it, right?

Not so. What is actually happening is that the photons are being absorbed by the atoms in the glass, and then re-emitted. This is the only reason that lenses work as they do. If light passed right through it, a convex lens would give you the same distortion as a flat glass: none. Eyeglasses wouldn't work, prisms wouldn't work, fiber optic wouldn't work...

#9 Posted by WhiteKnight77 (12605 posts) -
Ya know, I think this young lady (might be a G.I.R.L.) is nothing more than a spammer. She starts threads, hasn't made any replies in said threads except once, yet has a sig that advertises a pay for mentoring type system and uses that same company as her blog/profile banner. Something fishy if ya ask me.
#10 Posted by playmynutz (7876 posts) -
all i ever hear from the science channel is light travels at a constant speed. if light is a particle i wonder if you can eat it
#11 Posted by coolbeans90 (21305 posts) -

#12 Posted by LauraPortinari (67 posts) -
I know that we already knew light isn't a constant and can be slowed by a medium. Isn't that how refraction works? hmm...
#13 Posted by LauraPortinari (67 posts) -

coolbeans90
"it's a breakthrough though" xd
#14 Posted by Yusuke420 (2770 posts) -

I know that we already knew light isn't a constant and can be slowed by a medium. Isn't that how refraction works? hmm...LauraPortinari
Yeah but what this is talking about is that science didn't think there was anything in space to effect the travel of light. So the speed they have been using doesn't take into account these newly found particles.

#15 Posted by Nibroc420 (13571 posts) -

[QUOTE="LauraPortinari"] The greatest change might be to textbooks, which will need to add a caveat that the speed of light is constant, only in a true vacuum-which space isn't. The findings must still survive peer review before that happens. MannyDelgado

Silly. This is already a very well-known fact

Popular science reporting remains as sh*t as ever

This. we should note that even in the equation E=MC^2 C is "The speed to light in a vacuum" Scientists have been aware that light moves at different speeds in different mediums for quite some time..
#16 Posted by Nude_Dude (5372 posts) -
Brought to you by catholic online
#17 Posted by comp_atkins (34300 posts) -
[QUOTE="DirigiblePlums"][QUOTE="LauraPortinari"]Our God is a particle???. XD http://www.catholic.org/technology/story.php?id=50261 The current laws of physics says that light travels approximately 186,000 miles per second in a vacuum. That's been a handy fact that has allowed scientists to calculate the distances to faraway objects and to conduct other research with great accuracy. However, that measurement assumes that space is a vacuum. It isn't. Space is filled with tiny subatomic particles which although extremely diffuse, can theoretically slow down light just a tiny bit. How tiny? About 50 attoseconds per square meter of crossed vacuum. An attosecond is a one quintillionth (10^-18) of a second. An attosecond is to a second what a real second of time is to 31.71 billion years. So that's not a lot of egg on the face of physics. Still, over very great distances light from distant objects could be slowed just slightly. That slowing isn't enough to impact any currently accepted theories regarding physics, but it still suggests that even the most reliable of yardsticks may be variable after all. Very minor changes to currently accepted understandings may be required, but since the changes are so slight they might not be significant, and therefore unworthy of much modification. The greatest change might be to textbooks, which will need to add a caveat that the speed of light is constant, only in a true vacuum-which space isn't. The findings must still survive peer review before that happens.

But I don't quite understand. How could scientists overlook something as obvious as "space isn't a vacuumn."

perfect vacuum, no, but a vacuum for all practical purposes...
#18 Posted by MannyDelgado (1187 posts) -

[QUOTE="LauraPortinari"]I know that we already knew light isn't a constant and can be slowed by a medium. Isn't that how refraction works? hmm...Yusuke420

Yeah but what this is talking about is that science didn't think there was anything in space to effect the travel of light. So the speed they have been using doesn't take into account these newly found particles.

That's not a new discovery, either

http://en.wikipedia.org/wiki/Interstellar_medium

#19 Posted by The_Lipscomb (2603 posts) -

Good, lets keep the scientfic research flowing.

#20 Posted by coolbeans90 (21305 posts) -

I'm still trying to understand how this is news.

#21 Posted by The_Lipscomb (2603 posts) -

I'm still trying to understand how this is news.

coolbeans90
Is it? Well, I'm not very informed on this subject.. So it's new to me.. I'm doing some more research on it now.. Sometimes you have to repeat things.
#22 Posted by MannyDelgado (1187 posts) -

Better (i.e. not completely retarded) source

#23 Posted by Big_Pecks (5972 posts) -

#24 Posted by The_Lipscomb (2603 posts) -

Big_Pecks

That's the fun part of it.. It's so fascinating and complex.. I wish we knew so much more.

#25 Posted by LauraPortinari (67 posts) -

I think we all have come to a mutal agreement that the catholics are seriously behind in their facts. They just want God to exist so bad they will say anything. Religion is on its way out from all these newly found discoveries in which makes sense rather than all those stories our civilization was founded on.

#26 Posted by toast_burner (24692 posts) -

Light moves at different speeds through different substances.

Where have you been the last 100 years?

GOGOGOGURT

No it doesn't

Here's a quick video that explains it nicely

#27 Posted by MannyDelgado (1187 posts) -

[QUOTE="GOGOGOGURT"]

Light moves at different speeds through different substances.

Where have you been the last 100 years?

toast_burner

No it doesn't

Here's a quick video that explains it nicely

He's referring (giving him the benefit of the doubt) to the average speed, which varies by substance, whilst you're referring to the instantaneous speed

edit: By 'average speed' I mean the magnitude of the average velocity, rather than the average of the magnitude of the velocity

#28 Posted by GOGOGOGURT (4470 posts) -

[QUOTE="GOGOGOGURT"]

Light moves at different speeds through different substances.

Where have you been the last 100 years?

toast_burner

No it doesn't

Here's a quick video that explains it nicely

I actually watched the video and it said exactly what I said.

You are grasping at straws for an argument brah.

#29 Posted by Zeviander (9503 posts) -
I'm pretty sure advanced physics takes these things into consideration. It's general physics that makes the assumption for the sake of ease of calculation and teaching. I took some university astronomy classes and they very clearly said that space is not a vacuum... it's merely the ideal state to calculate distance. Black holes also ruin standard physics of light.
#30 Posted by toast_burner (24692 posts) -

[QUOTE="toast_burner"]

[QUOTE="GOGOGOGURT"]

Light moves at different speeds through different substances.

Where have you been the last 100 years?

GOGOGOGURT

No it doesn't

Here's a quick video that explains it nicely

I actually watched the video and it said exactly what I said.

You are grasping at straws for an argument brah.

Light doesn't change speeds, it just takes longer to travel through some substances as it has more distance to travel.

#31 Posted by Nibroc420 (13571 posts) -

Light doesn't change speeds, it just takes longer to travel through some substances

toast_burner

Herp Derp.

Cars dont change speed, the distance between the car and it's destination simply changes.

#32 Posted by MakeMeaSammitch (4889 posts) -

This sounds like something that's been known for like 300 years.

Light slows down and bends when going between mediums.

#33 Posted by Kats_RK (2080 posts) -

[QUOTE="Big_Pecks"]

The_Lipscomb

That's the fun part of it.. It's so fascinating and complex.. I wish we knew so much more.

Yep but we discover little by little.

#34 Posted by toast_burner (24692 posts) -

[QUOTE="toast_burner"]

Light doesn't change speeds, it just takes longer to travel through some substances

Nibroc420

Herp Derp.

Cars dont change speed, the distance between the car and it's destination simply changes.

What has that got to do with what I said? A car driving at 50MPH would take longer to drive a 100 mile journey than a 50 mile journey. That doesn't mean it's driving at a slower speed.

#35 Posted by DirigiblePlums (142 posts) -

[QUOTE="Big_Pecks"]