New Studies Suggest the Speed of Light is Variable

[hh5]

 mmm imagine hitting some speed bumps, lol

Thus far, textbook descriptions of the speed of light assume that the light is traveling in a vacuum.
 
Space, however, is not a vacuum.
...
First, Urban and his team propose that there are in fact a limited number of particle pairs including electron-positron or quark-antiquark pairs within a vacuum. This opens the possibility that the speed of light can then fluctuate at a level independent of the energy of each light quantom or photon. In other words, the speed of light would depend on the vacuum properties of space and time.

[JamesSavik]

It has been known for some time that different things can effect the speed of light: most notably gravity and gaseous matter.

[Graeme]

The new part appears to be that they think that the 'vacuum' of space isn't quite the vacuum it's usually assumed to be. Not sure what the impact would be, though, as all the theories that assume that the speed of light in a vacuum is a constant still stand. The major impact would probably be on astronomy, with estimates on age/distance based red-shifts may need some adjustment.

[hh5]

I guess for the academics ... being constant ... +/- gets to be applied with understanding the variable

so imagine for a SyFy like star trek ... things getting in the way of getting there

 

The new part appears to be that they think that the 'vacuum' of space isn't quite the vacuum it's usually assumed to be. Not sure what the impact would be, though, as all the theories that assume that the speed of light in a vacuum is a constant still stand. The major impact would probably be on astronomy, with estimates on age/distance based red-shifts may need some adjustment.

 

I was watching an episode where warf went through a quantum fisher ... sparking other realities ... it was also interesting to notice the elements in the many episodes that made up the final series finally ... 

 

Alternate realities or parallel time stuff ... what if Q was actually taking them into a sandbox to play with a different reality

 

The interesting thing ... in any science .. new theories coming up ... the many disagree ... its like freemarket science

but when it comes down to making something ... the different minds come together to do something ...

it is then when dissension seems to disappear

 

so while science is not coming up with Warp Drive ... we will speculate into the next generation of getting out of out solar system someday before our sun burns out or before earth becomes un-inhabitable

 

our current limitation is energy and how to transform it into a mode of transportation

the other question is when will humanity be mature enough to use it?

 

SOL being variable ... could that partially explain why it took awhile for the NASA to explain where Voyager is?

[hh5]

Amending the topic, it seems we're still children trying to learn about things in the big bang

 

http://www.livescience.com/28149-antimatter-magnetic-charge-measured.html

 

 

Scientists say they've made the most precise measurements to date of the magnetic charge of single particles of matter and its spooky counterpart antimatter.

 

A better understanding of the characteristics of these particles could help scientists solve one of the most baffling mysteries in physics: Why is the universe made of matter and not antimatter?

 

Theory suggests that protons and antiprotons should be virtually identical in their mass and magnitude of charge but that they should have opposite charges. While the new measurements fit within this model, better measurements of protons and antiprotons could shed light on why matter came to dominate in the universe.

 

[JamesSavik]

I remember reading that: the average density of space is 1 atom per 3 cubic centimeters.

 

That's pretty close to vacuum but it is an average meaning that density will be greater in some places and less in others..

 

While over short distances, this makes little difference but over many light years the effects add up.

 

One way that we see it is in the effects on the spectra of OB class stars and types of novae. Their spectra are very uniform and are often called a "standard candle" because of their uniformity. However- as their light transits light years of space, the absorption lines of interstellar gas and dust are superimposed on these spectra.

 

It is useful in that you can tell what the gas and dust are- typically hydrogen and carbon respectively. It gives us some idea that there is a lot of matter out there that we can't see. We can only induce that it is there by indirect means.

[hh5]

thanks james

besides gases in space ... isn't there lots of debris ... rock ... sand ... ice  ... planet breakup stuff?

lol, if we have a ship in a hydrogen gas cloud, don't our engines run the risk of igniting parts the cloud?

 

sounds like we need a force field to shield a ship from debris before we can travel the SOL

I think our current field is a magnetic field ... that works to repel gases and small particles

but I doubt that helps with bigger objects ... so what makes up a force field ... it does mean to repel or resist an object from breaking the field

 

other - there is a theory to repel an asteroid is to use its own gravity against it ... sounds weird but does that work?

 

it appears we do need more experiments in space ... do u think when we have a space station in the asteroid belt

we will learn more about space than on the ISS?

Edited March 26, 2013 by hh5

[JamesSavik]

Hydrogen in space (near vacuum) is inert. Either as an ion (H+) its diatomic form H₂ there is simply nothing for it to react with for combustion to occur.

 

Yes- we need to do a lot more in space.

 

Space (near vacuum, close to absolute zero in hard radiation) is the most common environment in the universe. Oxygen/Nitrogen rich atmosphere, between 273-300 degrees kelvin with so many average bars of atmospheric pressure is actually so strange in comparison to the rest of the universe that it makes for very poor laboratory condition with which to study the rest of the universe.

[C James]

Interesting article on measuring the magnetic polarity of antimatter, but I do see some errors, such as the claim that there is no naturally occurring antimatter remaining. The fact is we have no idea to what degree the universe is composted of antimatter, and in any case some naturally occurring antimatter has been found;

 

 

Hrmmm, as a guess, I'd say the article quoted in the first post (link) might have been written by a journalist who does not have a good grounding in particle physics, who thus buried the lede by choosing that headline.  As James mentions, the speed of light is variable when in a non-vacuum. For example, Cherenkov radiation (the blue glow seen in reactor cooling pools, etc) is created by particles exceeding the speed of light in a materiel (water, plastic, etc) where it is less than in a vacuum. 

 

Planck vacuum fluctuations have also been known (or at least accepted theory) for decades. What's been lacking is the ability to measure it. That's what, IMHO, the research mentioned in the article is aimed at (and it is mentioned, at the end). Energy equate to matter, so by finding a way to measure the density of vacuum, they should be able to observe the actual amount of vacuum energy.   

[canopus]

Antimatter is made in small amounts through energetic collisions all the time. The tiny amount in the Earth Van Allen belts would make 10 kilowatt-hours if fully tapped and annihilated. But it was all *produced* in collisions of ordinary matter particles accelerated through magnetic fields in the solar system.

 

 

If there were a region of the universe that was dominated by antimatter, the "interface" with the ordinary matter-dominated regions of the Universe produce a *lot* of 511 keV gamma rays. Satellites have been launched to look at this line -- not really to look for it in the Universe at large (because it's just not there in the amounts it would be if segments of the visible universe were antimatter-dominated) but to study energetic happenings in exotic objects in our own galaxy. You can search for things like 511 kev positron or the INTEGRAL spacecraft to find out more.

 

 

The complexity of the vacuum just keeps growing. In the 1930s physicists figured out that the vacuum wasn't really empty but was filled with "virtual" particles, an infinity of them, just waiting to get the energetic kick to make them real. The recent papers aren't saying there aren't an infinity of particles, just that they come in a finite number of types and that there may be hope of explaining some properties of the vacuum in terms of this spectrum of virtual particles. Maybe. As for the speed of light "variability", I gather than these discussions are at *extremely* small length scales, and that the random fluctuations rapidly smooth out over macroscopic distances.. but it's always possible that a tiny amount remain, and please fund efforts to look.

 

 

As far as gravity affecting the speed of light, one of the postulates of both special and general relativity is that the speed of light is *constant* for all inertial observers. The enormous success of relativity in describing fairly exotic situations in the universe gives great support to the validity of this hypothesis. In the geometry of relativity, a "light connection" between two points in spacetime (A shines a light at B, both events have a separation in space and time), the "proper length" in spacetime of such a connection is *zero*. This is deeply connected to causality, that events can be connected by a light cone, or else lie inside it(timelike) or outside (spacelike) -- causality preservation is the result of this separation of regions appearing invariant to all observers.

Edited March 30, 2013 by canopus

[C J]

Interesting stuff.  Looks like it's not a good idea to totally believe anything when it comes to the universe.

 

I'm not convinced there isn't more to learn about light itself, but I don't know a lot about it to start.  It seems logical though that since light consists of particles that exert force on the things it hits, then just having light in space would mean there isn't a total vacuum there.  I think it's possible there isn't anyplace that has a total vacuum, but maybe there is.   Maybe there are other universes, which is one of the most fascinating possibilities to me. 

 

So many questions, so little time.  I'm hoping for some fantastic kinds of discoveries.  It's some of the most exciting stuff there is, even for a amateur like me.