Posted on 01/10/2002 8:27:48 AM PST by Brett66
Edited on 04/29/2004 1:59:56 AM PDT by Jim Robinson. [history]
HUNTSVILLE, Alabama (CNN) --Scientists are looking into a futuristic technology that could lead to interplanetary missions and significantly improve cancer treatments to boot.
Astronauts have gone to the moon, but not other planets in large part because such a trip would require much more propulsion power and time. NASA researchers, however, are investigating antimatter for its propulsion potential.
(Excerpt) Read more at cnn.com ...
When a tumor meets an anti-tumor, the patient's worries are over. :-)
No, the smaller it is, the hotter it is.
Didn't Ron Jeremy star in that one? :)
We know that high energy charged particles can achieve superluminal speeds in transparent substances. If a high energy charged particle were to have achieved superluminal speed prior to hitting a vacuum, how would it be affected upon entering the vacuum? Enquiring minds want to know(no joke there)
As a massive particle aproaches the speed of light, it gains more mass. The faster it goes the more energy has to be put into it. The limit to this is light speed. At that point it would have infinite mass. Light travels at its highest speed in a vacuum, it can't go faster unless the polarizablity/dielectric constant, or permeability of free space of the vacuum goes lower, and it won't. The polarizability of matter is always higher than a vacuum, so particles always go slower when they it is around.
In all the articles I've looked at, where folks are claiming superluminal light speeds, what was really happening was the beam shape was changing and the speeds they were referencing were phase velocities. To understand phase velocities consider an arbitrary waveshape. It can be described by a sum of sin waves. The arbitrary wave, that's used to describe a particle travels at a group velocity, that can never be higher than light, unless it's a photon and then it's light speed. Now if that wave/particle interacts with something the group velocity will go down and the wave will change shape. That wave shape change requires the sin waves used to describe the wave to speed up to a new arrangement to describe the new shape. If it's a electromagnetic signal in a waveguide, the sine waves phase velocity can be much higher than the signal speed and all they due is determine the geometry of the fields in the guide.
Phase velocities occur whenever waves are analyzed, they occur in the mathematics to be able to describe the geometry, but not any real speed. The energy and all other measurables follow group velocity. So nothing will ever be able to determine a shape change, or phase velocity, until the signal, energy, or other measurable actually arrives. Particles never travel over c, only phase velocities in the math.
I've not looked into quantum entanglement and claims of instantaneous action at a distance, but I have a suspicion it's a phase thing, or the particles are not really free, but bound in some system.
Physicist says large black holes are cooler. I'll have to think about that more to know why. My description above was faulty, 'cause photons speed is independant of the frequency. That means they'd all escape if one did, regardless of energy.
Black hole temp, T=1/(8*pi*M*k).
M=mass of black hole
k=Boltzmann's const.
I wonder what the acceleration would be like. If it was high enough then any of the surviving astronauts will be about 1 inch tall and 100 inches wide.
BTW. We do want to stop it when we get to our destination. Don't we? Well that means negative acceleration. Like watching juveniles with a hot car. Acceleration like mad from the stop light. Then jamming on the brakes, deceleration, at the next red light.
To answer your second point first: All you have to do is accelerate for the first half of the trip, then decelerate for the second half.
As to your first point: The laws governing motion and acceleration were first enumerated by Isaac Newton in the 17th Century. In particular, the relevant law here is the one describing the relationship between distance , acceleration and time:
s = u.t + 1/2.f.t.t
Where s is the distance covered, u is the initial velocity (zero in this example), f is the acceleration and t is the elapsed time. (By the way, can anyone here tell me how to do subscripts and superscripts in HTML? It would have been really useful here).
Depending upon where in their respective orbits they are, the distance between Earth and Mars is between 80 and 400 million kilometers - let us take the larger of these, as it represents the extreme case. Halve that to get the distance over which the acceleration must be maintained - 200 million kilometers, or 200 billion meters. Now let us assume that we wish to cover this distance in one million seconds (about eleven and a half days, leading to a total trip-time of just under three and a half weeks).
To calculate the acceleration which will achieve this, we must divide the distance by half the square of the time, according to the law of acceleration. Doing so, we find that an acceleration of 0.4 meters per second per second will suffice. The acceleration due to the Earth's gravity at sea-level is more than twice as great as this.
In other words, even a small acceleration, if maintained continuously, will suffice to take a spaceship anywhere in the Solar System in no more than a few weeks. Furthermore, continuous acceleration would also solve the physiological problems associated with prolonged weightlessness.
Can anyone calculate the effect on Man-In-The-Moon Marigolds? ;-)
Nonsense. I've seen enough Star Trek to know better. Using antimatter, you'd be rippin' past Mars before shifting out of first gear.............
"But because no one knows where to find the antimatter, it has to be created. Scientists make it by colliding protons in particle accelerators at near light speed into targets made of nickel."
Cool!! I have lots of nickels!! Don't know 'bout y'all, but mine only cost about 5 cents!!!!!
"The world's largest maker of antimatter, the Fermi National Accelerator Laboratory in Batavia, Illinois, makes only one billionth of a gram a year at a cost of $80 million. At that rate, it would take one million years and $80 quadrillion (80,000 trillion) to produce one gram."
Damn. They must have the same accountant as my shyster lawyer and my mouth-hobbyist (aka "dentist"). That's almost as much as my butcher gets for prime rib............
Isn't that how the gov't pays for everything?
Yup, Ya gotta micro blackhole?
I love to see MY money spent this way.......if a hammer cost $2000.00 what did this box cost that is gonna carry something that they have no idea where to even find it. Cart before the horse isn't it......
That's a tax bill.
However, tachyons are imaginary particles(particles with imaginary properties) that don't exist. They pop up during the math during the developement of field theory. They are what folks find when the particles in their theory have real values inside of the vacuum(ie. imaginary mass here). The expectation values for the field in the vacuum is nonzero(ie. real mass there). Shifting the field to a new one, by the amount of what one had in the original vacuum, results in a new vacuum. A vacuum of different energy content and levels. When this is done, the original group of particles loses the tachyons and the symmetry of the original group of particles is broken and new massless bosons arise. The stardard model has a couple of Higgs bosons as carriers of mass to the massive particles at different energy scales.
The presence of tachyons in string theory just hint that symmetries can be broken leading to the correct real particles and at the same time lose them with the correct choice of vacuum. Supersymmetric strings have no tachyons. String theory is more of a theoreticians playground than a theory.
When it is said that one chooses a new vacuum, they are really shifting things in the equations when observables start to occur outside this universe. They aren't proposing to know anything about what's outside. They are just keeping the observables, observable.
Might ought to read "that we are currently unable to detect and confirm."
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