|MadSci Network: Physics|
An answer to your question ranges from the boring (blasters don’t exist, they are only a product of movie special effects) to the less boring (blaster-like weapons have been proposed in real life, but are not anything like what you see in the movies) to the kind of fun (of course blasters don’t exist, but let’s think about what kind of technology would go into making one). Let’s tackle these answers in order.
Of course we all know that blasters in movies are based on what the director thinks will look cool rather than on actual science. When you have a special-effects department working for you, you can make just about anything you like as long as you have the money to do so. But before we move on, I feel compelled to point out just how challenging such an effort is.
People take computer-generated effects too much for granted these days. In fact, the only way to produce realistic scenes is to properly model reality – which necessarily requires a detailed understanding of the way the world works, the mathematical acumen to express that to a computer, and the artistic talent needed to bridge the gap between what can’t really be calculated by today’s computers and what can be calculated yet still look good on screen. A true combination of these three skills in one person is quite rare. So, hiding behind the ‘boring’ answer is actually a real, burgeoning, and exciting field.
The slightly less-boring answer relates to blaster-like weapons that have been proposed in real life. One obvious candidate is the laser, while another candidate is accelerated-particle weapons. You may have heard of the Airborne Laser program, which is fielding a big laser in an airplane designed to ‘shoot’ down missiles. In an accelerated-particle weapon, ions or molecules are accelerated to near-light-speed energies and directed at a target to do their damage. An example of this is the Neutral Particle Beam program. These and other advanced weapons programs can be monitored at the special weapons monitor page of the Federation of American Scientists website.
The more-fun answer comes in trying to speculate on how you might get a blaster to actually work. This is where you can let your imagination roam a bit. However, I can see (based on the words you used in your question) that you’ve already found a resource where people have already done just this: the Turbolaser Commentaries. Since they’ve already spent far more time that I could to this question, I will defer to them as sources of what you could dream up to explain a blaster’s working parts.
I was pleased to see that they recognized the problems with trying to reconcile a light-based or accelerated-particle-based weapon with the very slow velocity of the blaster discharge. You can see the brightly colored streaks as they travel on-screen from a blaster to target, yet even for a ‘primitive’ real-life bullet the speed is fast enough that (were there a visible tail) it would look like an instantaneous line.
Despite all the technospeak there, however, most of the technology that they discuss (such as the actuator of your question) does not exist, so you should take their descriptions with a healthy grain of salt.
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