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E-M energy, whatever its wavelength, doesn't always travel at c. Remember your winter coat? The 'bending' of the straw in a glass of water?
13 things that do not make sense - space - 19 March 2005 - New Scientist1 The placebo effect
Don't try this at home. Several times a day, for several days, you induce pain in someone. You control the pain with morphine until the final day of the experiment, when you replace the morphine with saline solution. Guess what? The saline takes the pain away.
This is the placebo effect: somehow, sometimes, a whole lot of nothing can be very powerful. Except it's not quite nothing. When Fabrizio Benedetti of the University of Turin in Italy carried out the above experiment, he added a final twist by adding naloxone, a drug that blocks the effects of morphine, to the saline. The shocking result? The pain-relieving power of saline solution disappeared.
So what is going on? Doctors have known about the placebo effect for decades, and the naloxone result seems to show that the placebo effect is somehow biochemical. But apart from that, we simply don't know.
Benedetti has since shown that a saline placebo can also reduce tremors and muscle stiffness in people with Parkinson's disease. He and his team measured the activity of neurons in the patients' brains as they administered the saline. They found that individual neurons in the subthalamic nucleus (a common target for surgical attempts to relieve Parkinson's symptoms) began to fire less often when the saline was given, and with fewer "bursts" of firing - another feature associated with Parkinson's. The neuron activity decreased at the same time as the symptoms improved: the saline was definitely doing something.
We have a lot to learn about what is happening here, Benedetti says, but one thing is clear: the mind can affect the body's biochemistry. "The relationship between expectation and therapeutic outcome is a wonderful model to understand mind-body interaction," he says. Researchers now need to identify when and where placebo works. There may be diseases in which it has no effect. There may be a common mechanism in different illnesses. As yet, we just don't know.
2 The horizon problem
OUR universe appears to be unfathomably uniform. Look across space from one edge of the visible universe to the other, and you'll see that the microwave background radiation filling the cosmos is at the same temperature everywhere. That may not seem surprising until you consider that the two edges are nearly 28 billion light years apart and our universe is only 14 billion years old.
Nothing can travel faster than the speed of light, so there is no way heat radiation could have travelled between the two horizons to even out the hot and cold spots created in the big bang and leave the thermal equilibrium we see now.
This "horizon problem" is a big headache for cosmologists, so big that they have come up with some pretty wild solutions. "Inflation", for example.
You can solve the horizon problem by having the universe expand ultra-fast for a time, just after the big bang, blowing up by a factor of 1050 in 10-33 seconds. But is that just wishful thinking? "Inflation would be an explanation if it occurred," says University of Cambridge astronomer Martin Rees. The trouble is that no one knows what could have made that happen but see Inside inflation: after the big bang.
So, in effect, inflation solves one mystery only to invoke another. A variation in the speed of light could also solve the horizon problem - but this too is impotent in the face of the question "why?" In scientific terms, the uniform temperature of the background radiation remains an anomaly.
A variation in the speed of light could solve the problem, but this too is impotent in the face of the question 'why?'
3 Ultra-energetic cosmic rays
FOR more than a decade, physicists in Japan have been seeing cosmic rays that should not exist. Cosmic rays are particles - mostly protons but sometimes heavy atomic nuclei - that travel through the universe at close to the speed of light. Some cosmic rays detected on Earth are produced in violent events such as supernovae, but we still don't know the origins of the highest-energy particles, which are the most energetic particles ever seen in nature. But that's not the real mystery.
As cosmic-ray particles travel through space, they lose energy in collisions with the low-energy photons that pervade the universe, such as those of the cosmic microwave background radiation. Einstein's special theory of relativity dictates that any cosmic rays reaching Earth from a source outside our galaxy will have suffered so many energy-shedding collisions that their maximum possible energy is 5 × 1019 electronvolts. This is known as the Greisen-Zatsepin-Kuzmin limit.
Over the past decade, however, the University of Tokyo's Akeno Giant Air Shower Array - 111 particle detectors spread out over 100 square kilometres - has detected several cosmic rays above the GZK limit. In theory, they can only have come from within our galaxy, avoiding an energy-sapping journey across the cosmos. However, astronomers can find no source for these cosmic rays in our galaxy. So what is going on?
E-M energy, whatever its wavelength, doesn't always travel at c. Remember your winter coat? The 'bending' of the straw in a glass of water?
Got a cite for that? The "winter coat" and "bending straw" analogies are irrelevant. Niether prove your contention that E-M radiation will travel at less than the speed of light. Speed of light is a constant, at least according to Einstein. Your examples can both be explained without the need to change a constant.
Maybe they got it so wrong because 94% of scientist are Democrats?
E-M energy, whatever its wavelength, doesn't always travel at c. Remember your winter coat? The 'bending' of the straw in a glass of water?
Got a cite for that? The "winter coat" and "bending straw" analogies are irrelevant. Niether prove your contention that E-M radiation will travel at less than the speed of light. Speed of light is a constant, at least according to Einstein. Your examples can both be explained without the need to change a constant.
Fail, moron. the speed of light isn't a constant. The speed of light in a vacuum, when not affected by gravity, is a constant.
The straw in the glass of water is actually proof of the point; you're just to ignorant to know it and too stupid to google it.
Maybe they got it so wrong because 94% of scientist are Democrats?
Got what wrong?
lol
see: refractive index
Right... so gravity effects what, exactly?
we're back to the ether, it seems....
according to the general theory of relativity, the law of the constancy of the velocity of light in vacuo, which constitutes one of the two fundamental assumptions in the special theory of relativity [. . .] cannot claim any unlimited validity. A curvature of rays of light can only take place when the velocity of propagation of light varies with position
E-M energy, whatever its wavelength, doesn't always travel at c. Remember your winter coat? The 'bending' of the straw in a glass of water?
Got a cite for that? The "winter coat" and "bending straw" analogies are irrelevant. Niether prove your contention that E-M radiation will travel at less than the speed of light. Speed of light is a constant, at least according to Einstein. Your examples can both be explained without the need to change a constant.
Fail, moron. the speed of light isn't a constant. The speed of light in a vacuum, when not affected by gravity, is a constant.
The straw in the glass of water is actually proof of the point; you're just to ignorant to know it and too stupid to google it.
Umm what about black holes?
Light does not escape them. Stopping light would seem to me to impact it's speed?
Umm what about black holes?
Light does not escape them. Stopping light would seem to me to impact it's speed?
What black holes? We're talking about photons created at the BB. There would be no black holes for them to encounter. The question isn't, can light's speed be changed per se. It's the notion that two photons created at the BB couldn't be 28 billion light years apart after 14 billion years.
Umm what about black holes?
Light does not escape them. Stopping light would seem to me to impact it's speed?
What black holes? We're talking about photons created at the BB. There would be no black holes for them to encounter. The question isn't, can light's speed be changed per se. It's the notion that two photons created at the BB couldn't be 28 billion light years apart after 14 billion years.
LIght can be "bent" by gravity. How do we know how far away things are in a straight line since our observations are based on optical "line of sight" which may be curved.
We are no where near figuring out how the universe works.
Some of us just think we are, just as many in each generation does.
Umm what about black holes?
Light does not escape them. Stopping light would seem to me to impact it's speed?
What black holes? We're talking about photons created at the BB. There would be no black holes for them to encounter. The question isn't, can light's speed be changed per se. It's the notion that two photons created at the BB couldn't be 28 billion light years apart after 14 billion years.
LIght can be "bent" by gravity. How do we know how far away things are in a straight line since our observations are based on optical "line of sight" which may be curved.
We are no where near figuring out how the universe works.
Some of us just think we are, just as many in each generation does.
That was exactly the point I was trying to make in a very poor attempt. My quote:
Def of "singularity:
A point of infinite density and infinitesimal volume, at which space and time become infinitely distorted according to the theory of General Relativity. According to the big bang theory, a gravitational singularity existed at the beginning of the universe. Singularities are also believed to exist at the center of black holes.
The current rules and laws of this universe don't apply to a singularity. Time stands still for one. Who knows how these laws apply to the "Big Bang" and universal expansion?
We know the temperature was the same everywhere, but an explosion is always chaotic. Which means the temperature would vary. So obviously, the Big Bang wasn't a "typical" explosion.
Since we call black holes singularities and time stands still in the face of infinite gravity and gravity will bend light, as the photons are swallowed by the black hole, whose to say they don't actually increase in speed, after all, they are entering a place where universal laws don't apply.
It all depends on the frame of reference
It all depends on the frame of reference
No it does not.
If we could get ourselves outside of space-time and examine light independent of the constraints of space and time we might be able to detect changes in the rate of flow of light.
