A prominent physicist on TV once said that the problem with 'speculative science' is that is is almost always wrong. I, of course, immediately keyed in on the word, 'almost'. That means that speculative science is right, now and then. Well, that's good news. That means that wild speculation might lead to real scientific discoveries! Without all that nasty math, too! Well, on with the speculation:
When you see one of those old films of a nuclear detonation, you see a "blast wave" hitting buildings like an unimaginable hurricane. Then, a few seconds later, the return blast is nearly as bad. So, why not just detonate a nuclear bomb next to an asteroid to knock it off course. Obviously, there's no air in space, so the asteroid would just get really hot from all the radiation. There might be a little thrust due to matter vaporizing on the surface, but certainly no "blast wave." Basically, there's no matter (air) to heat to convert the electromagnetic energy into kinetic energy. The answer is simple; surround the nuke with water (or other matter). Imagine a huge tank of water at the space station, useful for protecting the inhabitants from sudden solar flares. When an asteroid approaches, stick a nuke in the middle of the tank and boost it out along an intersecting trajectory. When it gets in the right position, detonate it, and the asteroid is slammed by extremely energetic water molecules, all going in the same direction. The water "pushes off" the water moving in the opposite direction. Small asteroids like the one coming near later this year could be nudged at the last minute by such a device; the kinetic energy transfer would be significant.
The following is an alternative explanation to the 'extra' gravity we seem to observe in galaxies, currently attributed to 'dark matter'. Assume that there is a massive black hole at the center of all large galaxies and that the black hole is constantly accreting matter. That seems reasonable in light of the massive amount of matter spit out by the billions of stars in the galaxy. Now, imagine an atom entering the tremendous gravity gradient near the event horizon of the black hole. The electrons will spend a portion of their time in a higher field when they are on the black hole side of their orbit due to the steep gravity gradient. When in that more intense gravity, they will experience increased time dilation and will seem to linger a bit longer on that side of the atom. The result is that the atoms will exhibit a charge felt by neighbors further out, and, therefore, the black hole will appear slightly positive to the rest of the galaxy. This effective positive charge will attract electrons from the ionized gas that fills the galaxy. Filaments of current will travel between nearby stars and the black hole and between stars further away. (Electrons will stream toward the center of the galaxy and positive ions will stream toward outer stars.) These current filaments will conduct the electric force much the same way a string of paper clips conduct a magnetic field much further than without the clips. The stars will be attracted to each other by a force that doesn't drop off as quickly as might be expected and which can be quite powerful despite the small charges involved due to the relative strength of the electric force to the gravitational force. When this flood of electrons reaches the black hole, they encounter a hidden surplus of electrons. The electric force being so much more powerful than gravity, these electrons are deflected along the event horizon and collide at the poles, spraying into space at right-angles to the disk of the galaxy. Meanwhile, positive ions are being repelled out of the galaxy along the plane of the disk. These positive ions and electrons are attracted to each other and bend around to form a lens-shaped halo of both ions and recombined atoms around the galaxy.
Here are some results:
The ion filaments conduct electric force, attracting the stars to the center of the galaxy, explaining the missing gravity. This force does not drop off by 1/r2 due to the flow of ions between stars. The charge is replaced by the continual matter accretion.
The neutral atoms in the halo around the galaxy act as an ordinary lens, adding to Einstein's gravitational lens due to the mass of the galaxy.
Cosmic rays approaching the galaxy spend hundreds of thousands or even millions of years being accelerated by these electric fields due to the size of the galaxy, explaining the unusual energy these particles exhibit. Electric fields within the galaxy deflect and accelerate these particles so that they arrive from a variety of directions and with a spread in energy. Cosmic rays originating within the galaxy would tend to be confined to the disk of the galaxy and be accelerating in a generally outward direction, but with randomized paths due to the complex electric and magnetic fields within the galaxy. The relative lack of electron cosmic rays isn't surprising in this scenario; near the black hole, where the acceleration is more linear, they are going the wrong direction. Whereas, the positive ions get a swift kick in the pants towards the stars, and, as they travel along the filaments of current, they experience more acceleration.
Colliding galaxies will seem to have an invisible dark matter gravitational overshoot due to the matter halo that is only loosely held by gravity. These particles are moving mainly under the influence of the electric field and will exhibit their own inertia. This halo overshoot produces a lopsided lens extending past the galaxy in the direction of the galaxy at time of collision, mimicking dark matter overshoot.
Objects (like spacecraft) leaving the solar system will be exposed to the electric field and will have a small charge induced across their surface. This induced charge will cause a very slight force that will slightly change the velocity. Near a star, the copious ions will shield the galactic electric field.
The recombining ions would generate photons of energy proportional to their energy. That might explain this: http://www.telegraph.co.uk/science/space/8125127/Giant-space-bubbles-baffle-astronomers.html X-rays would be expected by such high-velocity marriages.
This excessively speculative theory suggests that the steady-state, infinite universe and the big-bang universe are both 'sort-of' correct. Imagine that the structure of the universe in the time dimension behaves like Gabriel's Horn (1/x rotated around the axis to form a cone). If one could observe the universe from the 'outside', wherever that would be, one would observe an infinite timeline tapering off to a line. From the inside, looking up the neck of that horn (looking back in time) one would see the density of the universe growing and the size shrinking until reaching a singularity of infinite density in a finite time. From the outside, the surface area of the universe would appear infinite and from the inside, the volume would seem finite, at least regarding the time dimension. So, we're inside Gabriel's Horn which is why we think there was a Big Bang; there was, from our perspective.
This theory relies on those recent observations of very old galaxies that appear to not have heavier elements being incorrect in some way. Now there's an inconvenient truth. On the other hand, if alpha is found to be a "variable constant," as some experiments are suggesting, then maybe there are no heavy elements out there, simply due to a different alpha value in that region.
One must wonder what keeps things wound up, too. I suppose the Big Bang theory doesn't really address the wind up, either. (By 'wound up' I mean whatever gave the universe the organization or energy to begin with, or continues to supply it in a steady-state universe.) Both theories suffer from that one!
Apparently, there was some sort of inflation period that lasted for some fraction of a second after the Big Bang that managed to stretch the universe to unimaginable dimensions, starting from a singularity. Without knowing what the heck happened, isn't it reasonable to imagine that the effect ended exponentially? Or, stated another way, it never ended; it just got really, really small. Perhaps the extra red-shift seen in very distant (and therefore old) galaxies is due to our 'looking up the tail' of that exponential. There wouldn't be much left after so many time constants but it started out at an unknown number that was absolutely huge. We don't know how much we can't see since the light hasn't arrived yet. I suppose the speed at which inflation seemed to end suggests it would be totally gone in a few seconds but maybe there is more than one exponential associated with the phenomenon. Since such a bizarre physical process is thought to exist, who can confidently say it couldn't have a residual term with a longer time-constant.
All things being equal, the least interesting explanation is usually the right one. Or, if something seems too interesting to be true, it isn't.
Any measurement that relies on human perception is hopelessly disturbed by the perception. (Annoying extension of Heisenberg.)
Extraordinary claims require extraordinary lies.
Valid scientific theories should not contain the phrase, "before it's too late..."