I understand that the speed of light is the universe’s speed limit and that many forms of energy travel at that speed. Are there any other natural entities that approach the SOL? If light is the fastest thing in the universe, what’s second?
Speed of gravity.
I was lumping gravity into the category of things that moved at the SOL. Link. So that wouldn’t actually be the seconded fastest thing, would it?
On 23 February 1987, earth based telescopes picked up light from a supernova in the Large Magellanic Cloud. A neutrino detection facility in Japan, as well as one in Ohio(?) picked up a burst of neutrinos on the same day. They are thought to come from the supernova. If that’s true, and people are still arguing about it, the neutrinos travelled from the site of the supernova at 99.999998% of the speed of light.
Supernova 1987A
TheSpeed of dark of course.
You must understand that the speed of light is something else altogether. For instance even though the above neutrinos travel at 99.999998% c, you could still theoretically catch up and even pass them. On the other hand no matter how fast you travel light will still recede from you at the speed of light.
Huh? I thought neutrinos had no intrinsic rest mass (or whatever the current correct term is) and therefore travel at exactly c.
The OP isn’t really answerable. Energy quanta move at c in a vacuum. Those things that have mass can’t, but they can go as fast as they want up to that point (if something keeps pouring energy into them).
Massy things don’t have a ‘natural’ speed like energy does, so any particle (or system of particles) could be the second-fastest at different times and under different conditions.
The second fastest thing? Light in a medium.
Solving the Solar Neutrino Mystery
Neutrino oscillations are here to stay
So at least some types of neutrinos have mass.
The current thinking seems to be that neutrinos have very small rest masses. There are three types (called flavors usually) of neutrinos, the electron, muon and tau and their anit-particles. Experimental evidence seems to show that these three types of neutrinos can change into one another. According to the generally accpeted theory this could only be true if they have rest masses.
That neutrinos could change types (oscillate is the usual word) was first suspected when test of the solar neutrino flux was found to be only about a third of the expected value. The sun produces neutrinos when during fusion of hydrogen a proton converts to a neutron, a positron, and an electron neutrino. Since we know the soalr output of energy, we have a good estimate of the number of neutrinos produced and how many we should detect. The oscillation was proposed as a theoretical way to explain this discrepancy as the experiment would only detect electron neutrinos, and roughly only one third would be electron neutrinos once the oscillation reached steady state.
Request permission, KRM, for a slight hijack. I understand gravity lensing at a basic level. How did the observation described in your link enable the observers to calculate the speed of gravity? (As distinguished from merely confirming the lensing effect itself.) I gather better minds than mine had similar objections. Not looking to open a separate debate. A link to a site or two discussing the issue would be more than adequate. Thanks. [/hijack]
Hijack away. Just don’t look at me for an answer. 
In answer to the OP, the answer has to be MONEY. Other than the speed of light, nothing goes faster than money.
“Cosmic rays travel close enough to the speed of light that standard calculators do not have enough places to display the difference.”
cite (Not a great one I admit.)
And cosmic rays are definitely made up of particles that have rest mass.
Actually, there’s a phenomenon known as the “GZK cutoff” which is supposed to place something of a speed limit on the cosmic rays. Basically, if a proton is moving fast enough, it can collide with a photon from the cosmic microwave background and turn into particles with lower energy.
However, this doesn’t say that cosmic rays can’t move faster than this speed, merely that they won’t last too long if they do.
Gossip is even faster, and preceeds the loss of money in many cases.
True, but it’s an easy enough back-of-the-envelope calculation to estimate the difference between their speeds and that of light.
For example, the highest energy cosmic ray event ever observed was that seen in 1991, which had an energy of 320 EeV. (This is above the GZK cutoff, but not by much.) Whatever the triggering particle was, it had an energy far higher than anything that can yet be produced in a lab. If we define d = 1 - v/c, then if it were a proton one roughly gets d = 10[sup]-24[/sup]. In other words it would have been travelling at about 0.999999999999999999999999 c.
However, whatever it was that was caused such a cosmic ray originally might (though not certainly) also be producing neutrinos of roughly the same energy. Guessing 0.1 eV for the mass of the electron neutrino gives something like d = 10[sup]-44[/sup]. Of course, we can’t expect to detect such neutrinos, but they may be out there.
Bad news.
That’s interesting. Sorry for hijack, but the following should be of interest to the scientific types on this thread:
The Dark Sucker Theory
For years, it has been believed that electric bulbs emit light, but recent information has proved otherwise. Electric bulbs don’t emit light; they suck dark. Thus, we call these bulbs Dark Suckers. The Dark Sucker Theory and the existence of dark suckers prove that dark has mass and is heavier than light.
First, the basis of the Dark Sucker Theory is that electric bulbs suck dark. For example, take the Dark Sucker in the room you are in. There is much less dark right next to it than there is elsewhere. The larger the Dark Sucker, the greater its capacity to suck dark. Dark Suckers in the parking lot have a much greater capacity to suck dark than the ones in this room. So with all
things, Dark Suckers don’t last forever. Once they are full of dark, they can no longer suck. This is proven by the dark spot on a full Dark Sucker.
A candle is a primitive Dark Sucker. A new candle has a white wick. You can see that after the first use, the wick turns black, representing all the dark that has been sucked into it. If you put a pencil next to the wick of an operating candle, it will turn black. This is because it got in the way of the dark flowing into the candle. One of the disadvantages of these primitive Dark
Suckers is their limited range.
There are also portable Dark Suckers. In these, the bulbs can’t handle all the dark by themselves and must be aided by a Dark Storage Unit. When the Dark Storage Unit is full, it must be either emptied or replaced before the portable Dark Sucker can operate again.
Dark has mass. When dark goes into a Dark Sucker, friction from the mass generates heat. Thus, it is not wise to touch an perating Dark Sucker. Candles present a special problem as the mass must travel into a solid wick instead of through clear glass. This generates a great amount of heat and therefore it’s not wise to touch an operating candle.
Also, dark is heavier than light. If you were to swim just below the
surface of the lake, you would see a lot of light. If you were to slowly swim deeper and deeper, you would notice it getting darker and darker. When you get really deep, you would be in total darkness. This is because the heavier dark sinks to the bottom of the lake and the lighter light floats at the top. The is
why it is called light.
Finally, we must prove that dark is faster than light. If you were to stand in a lit room in front of a closed, dark closet, and slowly opened the closet door, you would see the light slowly enter the closet. But since dark is so fast, you would not be able to see the dark leave the closet.
Next time you see an electric bulb, remember that it is a Dark Sucker.