Massive objects going 99.9% speed of light.

[mapper]

Found this interesting, is this for real?



http://www.cnn.com/2005/TECH/space/01/18/universe.speed/index.html

(SPACE.com) -- If you're light, it's fairly easy to travel at your own speed -- that is to say 186,282 miles per second or 299,800 kilometers per second.

But if you are matter, then it's another matter altogether.

Nothing we know of zips along more quickly than light. Einstein, nearly 100 years ago, said it's not possible. For us, the speed limit makes strange sense: Go faster than light, and you could return before you've left, become your own grandpa, or other perform other leaps of cosmic logic.

Fast forward a century. Astronomers are now measuring stuff -- material, matter, things -- that moves at so close to the speed of light you might think it'd make Einstein a bit nervous. His theory of relativity appears not to be endangered by the blazing speeds, though.

Among thee speed demons of the universe are Jupiter-sized blobs of hot gas embedded in streams of material ejected from hyperactive galaxies known as blazars. Last week at a meeting here of the American Astronomical Society, scientists announced they had measured blobs in blazar jets screaming through space at 99.9 percent of light-speed.

"This tells us that the physical processes at the cores of these galaxies ... are extremely energetic and are capable of propelling matter very close to the absolute cosmic speed limit," said Glenn Piner of Whittier College in Whittier, California.

Ponder the power of the fast moving superheated gas, known as plasma:

"To accelerate a bowling ball to the speed newly measured in these blazars would require all the energy produced in the world for an entire week," Piner said. "And the blobs of plasma in these jets are at least as massive as a large planet."

The blazar jets are running around the universe in some fast company. Slightly faster, in fact.

In another study presented at the meeting, ultra high-energy cosmic rays thought to originate in a collision of galaxy clusters are slamming into Earth's atmosphere at more than 99.9 percent of the speed of light. Measurements put the number at 99.9 followed by 19 more nines -- about as close to light-speed as you can get without splitting hairs.

The particles are not light, but actual matter. They are tiny, thought to be mostly protons, but the energy that motivates them is similarly fantastic, and the mechanisms may be intertwined.

Scientists still don't know the exact mechanisms involved in accelerating matter to such high speeds, however. In the case of a blazars, it appears a black hole is involved. Anchoring an active galaxy, a supermassive black hole draws gas inward. Some is swallowed, yet some is simply accelerated and then ejected in high-speed jets along the galaxy's axis of rotation. Intense, twisted magnetic fields may play a role.

Some ultra high-energy cosmic rays might originate in blazar jets, Piner told SPACE.com. But other phenomena may serve as particle accelerators in space, such as merging galaxies or colliding black holes.

Piner and his colleagues observed three blazars, known from previous observations to be super speedy, using the National Science Foundation's Very Long Baseline Array radio observatory.

The results confirm the previous work and pin down the speeds with greater accuracy. The phenomenal pace of the plasma blobs looks to have reached a limit.

"All the results from blazar jet observations are in agreement with Einstein's Theory of Special Relativity," Piner said. "The jets are accelerated right up to the edge of the speed-of-light barrier but not beyond, even though these are some of the most efficient accelerators in the universe."

 

[kavius]

The jets are accelerated right up to the edge of the speed-of-light barrier but not beyond, even though these are some of the most efficient accelerators in the universe

I read this as the article taking this as proof that particles cannot travel at the speed of light, but would it be possible to measure a particle traveling at, or faster, than the speed of light? While I don't agree with the moving backward in time theories, it would an object moving that fast would be tricky to detect.

 

[lavalamp]

I wouldn't have thought that measuring the speed of something moving fester than the speed of light would be difficult. You see the particle at point A, you see the particle at point B, find the distance between the points and the time it took to move that far and you have your speed.

Assuming that it is possible for something to travel faster than light, it should be possible for that object to interact with light, much like if a concorde were to fly by at Mach 2 you'd probably notice even if you were looking the other way and could only hear it.

 

[marcus]

come on you two, there is nothing here about particles traveling the speed of light (much less faster)

mapper asked, "is this for real"

certainly as far as I know it is, as regards what you quoted, it is real

I can't vouch for the details but this is essentially a familiar story

man-made acclerators accelerate particles like
protons to speeds very close to light
and have for decades

and cosmic ray energies have been measured at 50 joules and up,
that has been known for decades too,
and a proton going so fast it has a kinetic energy of 50 joules has to be
going 99.999999... percent of speed of light (many nines...)

all this does is confirm the special relativity theory which is the basis of the belief that c is a universal speed limit.

THAT COULD BE WRONG and in fact maybe things do go faster than c, but all the evidence that mapper is giving us is not indicating any violation of ordinary special rel. In what you are discussing there is no requirement to change the usual picture.

 

[Chronos]

With faster than light speed, the problem is in the math. In relativity, you end up with division by zero when any form of mass reaches the speed of light. This sort of occurence is typically called an unphysical result - meaning it does not actually occur in the physical universe. Objects made of ordinary mass can only travel up to, but not as fast as light. Objects made of imaginary mass [square root of a negative number], could travel at any speed, down to but never as slow as light. So, mathematically, there is no type of mass that can travel precisely at the speed of light. That privilege is strictly reserved for massless particles, which are forbidden to travel at any speed other than light. I suppose in principle you could accelerate ordinary mass up to the speed of light, convert it to photons, then convert the photons to imaginary mass and resume accelerating to your hearts content. Aside from the fact there is no theory to suggest such a conversion is possible, I doubt it would be a pleasant experience. Reassembling reformed particles back into the original configuration would be a quite a task and require a really big computer.

 

[LURCH]

Does the article mention the mass of the plasma blobs in blazars? I mean, I would assume this statement:

"...the blobs of plasma in these jets are at least as massive as a large planet."

is referring to the rest mass of the blob. At 99.9c, the mass should be many thousands of times greater, shouldn't it?

 

[RandallB]

I wouldn't have thought that measuring the speed of something moving fester than the speed of light would be difficult.
much like if a concorde were to fly by at Mach 2

So what would be so simple about measuring the speed of the Concorde if you could only use sound marks to "See" where it was?
The BOOM you just heard started right next to you and then traveled out and away from you in both directions. You'd need to listen close for a Doppler effect just to figure out which way it was going.

If there was something to go by us at >c. The "Light boom" from a warp speed ship interacting with space dust would give a light trail extending out in both directions, appearing near us and then going off in two directions.

For all the looking in space we've done having not seen such an event is partial confirmation of SR on its own. Even if you don't trust the math of SR yet.

 

[shrumeo]

Layman with a stupid question.

The article doesn't mention what this near-light velocity is relative to.
Is going 0.999c wrt the "blazar" or wrt the Earth? Both?

I understand that light is going c wrt to every frame of reference,
but what about matter moving close to c?

 

[Chronos]

The article doesn't mention what this near-light velocity is relative to.
Is going 0.999c wrt the "blazar" or wrt the Earth? Both?

I understand that light is going c wrt to every frame of reference,
but what about matter moving close to c?

With respect to earth. The velocity is derived from the observed [from earth] doppler shift.The speed of light is relative to the object in motion and the observer. If another object was traveling in the same direction and speed as the blazar jet, the blazar jet would appear to be stationary to that observer. However, to that observer, just about everything else in the universe would appear to be going darn near the speed of light.

 

[chronon]

The article doesn't mention what this near-light velocity is relative to.
Is going 0.999c wrt the "blazar" or wrt the Earth? Both?

This is a good question, since the expansion of the universe complicates things. If the recession velocity of the blazar isn't too great, say 0.3c then it doesn't much matter since using special relativity we get 0.999c-0.3c=0.998c

However, cosmologists use the proper time of objects moving with the expansion as a time coordinate, leading to a coordinate system which is not consistent with special relativity. In particular, the blazar might be moving away from us at twice the speed light - so if the jet has a relative velocity towards us of 0.999c then what is the resultant velocity?

In fact it is likely to be blueshifted, as is shown in http://arxiv.org/abs/astro-ph/?0104349, but whether it's moving towards us or away from us is a debatable point. My feeling is that the cosmologist's coordinate system is unsuitable to describe velocities of distant objects. I've discussed this further on my website: http://www.chronon.org/Articles/milne_cosmology.html

 

[Oran]

I wouldn't have thought that measuring the speed of something moving fester than the speed of light would be difficult. You see the particle at point A, you see the particle at point B, find the distance between the points and the time it took to move that far and you have your speed.

This is actually wrong. If the particle is moving faster than the speed of light you will see it at point B before you see it at point A!

 

[Chronos]

... cosmologists use the proper time of objects moving with the expansion as a time coordinate, leading to a coordinate system which is not consistent with special relativity.

Any such cosmologists do not understand relativity.

..In particular, the blazar might be moving away from us at twice the speed light - so if the jet has a relative velocity towards us of 0.999c then what is the resultant velocity?

.999c, if you do the math.

...In fact it is likely to be blueshifted, as is shown in http://arxiv.org/abs/astro-ph/?0104349, but whether it's moving towards us or away from us is a debatable point.

Not really. Cosmological redshift does not go away that easily.

My feeling is that the cosmologist's coordinate system is unsuitable to describe velocities of distant objects.

What cosmologist's coordinate system are you talking about? Are you saying redshift does not mean distance? If so, please cite examples of high redshift objects observed superimposed in front of lower redshifted objects at Z>1. Even a single, high quality example would be appreciated.

 

[chronon]

Any such cosmologists do not understand relativity
...
What cosmologist's coordinate system are you talking about?

The diagram on Ned Wright's website at http://www.astro.ucla.edu/~wright/cosmo_03.htm#MSTD shows the sort of coordinate system in general use by cosmologists. I would say that this wasn't compatible with special relativity because (1) some objects are traveling faster than c and (2) the speed of light is not constant. In fact looking at the red line as a possible light beam, we see it first moving away from us, and then towards us.

..999c, if you do the math.

The example I had in mind was of a blazar receding from us, but with a jet coming out of the blazar at 0.999c wrt the blazar. The question is what is the resultant velocity of the jet wrt us. I admit that the original quote had particles moving wrt us at 0.999c, in which case maybe the question should be turned round to ask what velocity they originally had wrt the emitting object.

Not really. Cosmological redshift does not go away that easily.

The paper quoted shows that such a jet would be blueshifted. I would explain this by saying that the blazar was actually receding from us at less than 0.999c, and so the jet was approaching us. Some would say that the blazar is receding at 2c, so the jet is also receding at 1.001c, and the blueshift is some strange 'cosmological' effect.

Are you saying redshift does not mean distance?

Goodness me, No. I'm saying that I prefer a coordinate system where the upper limit of velocities is c, and the redshift/velocity relation is given by the special relativistic formula.