Thursday, July 15, 2010

Big Bang Science

Well, I was about to create a post devoted to answering the sheer minefield of Scientific queries raised by the hit comedy The Big Bang Theory. Unfortunately a real physicist who writes the science in the script has already explained himself in his blog http://thebigblogtheory.wordpress.com/, so I'll just post this link and call it a day. No, I intend to criticize his explanation of S03E22: The Staircase Implementation. I believe that the rocket fuel should have been added to the model rocket before adding the catalyst as a safety precaution. After all the reaction would theoretically start as soon as any amount of catalyst is added. Technically the catalyst should have only been added when the rocket was ready for launch. His use of the square-cube law only means that the fuel would explode nearly immediately instead of "combust"( technically it does not burn. It simply decomposes and expels huge volumes of gas and heat. Hence combust is wrong) gradually as is expected of a rocket launch. Even if it were non-explosive a slowly "combusting" bottle of fuel is still pretty dangerous.

Secondly I criticize the show itself since an applied physicist of any standing could never make such a simple mistake- imagine the problems that could happen to an actual space launch. On the other hand I love the concept of exposing people to physics so I forgive you guys.

Sunday, July 11, 2010

Parallel Universes in comic books


Marvel, DC, they all have them. No, not super heroes dressed in tights with pecs bigger than the chests of most women ( We wonder why men like looking at other men with cleavage, though perhaps we'd best leave it at that). Rather, we explore the concept of parallel universes. There's the 52 comic in DC, and the spiderman multiverse in Marvel just to name two.

Why do they create these far-out otherworlds? Well, the most common reason would be to explore what-if scenarios such as "what-if Lex Luthor really does kill Superman" without the nitty gritty problem of the character actually dying or changing in the main comic theme. This allows them to revive interest on the one hand while not changing the comic to the extent that readers can no longer recognise the characters. Its a win-win really, though it's also a really cheap trick.

Ok, heres the science behind it all. There are many views on the possibile explainations of parallel universes, one such begins at The Begining: the big bang theory. The universe was not always in existance and in fact exploded into being from a point singularity. Scientists speculate that all that energy and mass could have been channeled from another universe, hence black holes in our universe potentially lead to "light holes" and the creation of children universes. Another theory starts at the collapse of a universe, as gravity pulls all mass and space together into the size of a....for fun's sake lets say pineapple. This eventually becomes unstable and explodes into children universe. Thus theoretically infinite universes exist that die, unfold in an eternal symphony. Some have entirely different physical properties, some similar, possibly so similar that we might well have an almost exact replica of earth.

Another theory plays on our very perception. As people we experience three dimensions, excluding time which is not a spatial dimension, forward-backward, sideways, upward-downward. we can experience these three dimensions and anything within them. Lets suppose we live on a piece of paper, 2 dimensions are our world. We perceive Foreward-backward and up-down, but not sideways through the paper. Thus a 2d man would not be able to see outsied of the page, as he cannot perceive it. Another page is place next to his but he does not perceive that page. Suppose that 3d is not all we have. if there were 4d, sideways,up-down, foreward-backward aaannndd.....banana, we would not be able to observe another 3d world placed parallel to ours in the direction of the 4th dimension-in this case banana.

Lets say you punch a hole in 2d man's universe with a pencil. He does not perceive the pencil but thanks you (you are "god" in this case-just this case so do not go poking people with pencils)for the nice ball. If such higher dimensions do exist, the very objects we use and see could be verry different....a simple papaya could be a higher-dimension's alien booger because only the papaya shape is all we could perceieve. Thats not likely but it as possible as most far out fantasy book claims. Anyway I hate that fruit so it may as well be alien booger.

Do note that actual physics theory is far more complex and involves strings, membranes, bosons and a number of complex mathematical equations.

Science Fiction Double Post: Lightsaber Science











Ok, here's my second post and it touches on Science Fiction once more- this time the science behind the Lightsaber. May the force be with me, because this will be hard. Ok, first off many often call a lightsaber a "laser sword". the thing is, a laser being an intense beam of light would not end at a certain length nor would it cast a shadow as it certainly does. Cleverly enough, George Lucas, or someone at lucas arts, used real physics to create a plausible and believable lightsaber.



Plasma



Ok, you know there are three states of matter, solid, liquid and gas. There is a fourth state that is rarely used in elementary science- plasma! Sci-fi writers the world over did not create it- it was and still is present in the most common of objects such as neon tubes, plasma screen TVs (obviously!) and the Sun itself! In fact plasma accounts for the greatest source of mass in the universe. Now what is plasma and what the heck does it have to do with light sabers? Well plasma is basically ionized gas- at least 1% ionized to be exact. This gas begins to display some very non-gasious behavior, for example it now becomes an excellent conductor of electricity. Those of you in the know would realize that if that were true of normal gasses any source of power such as a wall socket could potentially cause you, your house, your pet dog and probably your mango to be zapped to kingdom come - lightning is a good example of what happens when sufficient air is ionized to send excess charge from the clouds streaking down to the earth.



First let's picture a "simpler" weapon: A blaster merely emits a highly accelerated projected shaft of highly ionized plasma this is perfectly plausible in terms of physics although it is questionable whether true blasters really have that sufficient range. We are talking about ejecting a highly ionized gas, which would tend to disperse. This is apparently kept in shape by the sheer velocity of the particles. Light sabers are similar, with one exception: A mysterious force field limits the length of the plasma blade, while redirecting it back toward the hilt in an endless cycle. This allows for a much smaller energy source in the hilt, since the plasma is not continuously lost to the air around it.



Force Field



The fact is that use of a force field to contain the plasma is plausible: ionized particles are affected by magnetic fields. The mysterious "force field" may well be a magnetic field. In fact this very phenomenon is illustrated by the creation of plasma windows, a layer of plasma bound by magnetic fields. However plasma windows are well....not really ideal for frying anything. If anything they create an almost true to life force field as they repel any object that attempts to enter it. The plasma now charges anything that attempts to break the field and repels it. Charges of the same ionization tend to repel, and the object is repelled before it can be captured by the magnetic field. The only explanation left is that the magnetic field collapses on contact, allowing the plasma to rush out at the point of contact. The emission of plasma raises another question: in theory this means that a person cutting anything with the plasma blade will be pushed backwards. No exertion to counter this backward force is noted on any jedi, so one can only assume that the writers did not take this fact into account. Then there's the question of how a magnetic field can be emited by the hilt to encompass the entire blade- that cannot be explained at all.



A light saber is perfectly possible, though the equipment used to create it perfectly impossible. Its uses are also limited, though there is a ray of hope for force fields!