Things You can Do with a WMD

If your knowledge is lacking, historically…

A WMD stands for a Weapon of Mass Destruction. Commonly they refer to nuclear weapons: fission based and fusion based. Fusion based weapons are more powerful. I will talk about fusion based weapons. Because they make a bigger bang. I like big bangs.

Remember Hiroshima and Nagasaki?

Exactly. But fusion reactions are three to four times more energetic than fission. Therefore their destructive output is significantly larger. Add this to the fact that unlike fission that requires a critical reactant mass to happen, fusion can happen for an indefinite time, given that the right conditions are present. Therefore a fusion based weapon can lead to a potentially cataclysmic, near-apocalypse outcome.

But Lets think positively: Infinite Energy

That was an overstatement. But for humans, there is no difference. Fission (usually) requires Uranium-235. That isotope is only 0.72% abundant. On earth, there are an estimated 5.5 million tonnes of Uranium, which means about 36,000 tones of fissile Uranium. Compared to this we have about 4.68 trillion tonnes of oil reserves. Fusion, however, requires hydrogen atoms. Most of the hydrogen atoms on earth are tried up in water in the oceans. Compared to these two, we have 15 million trillion tonnes of hydrogen in the oceans. How’s that for unlimited?

…and Exploring the Ends of our Galaxy

Another overstatement. Poetic licence, you see. Anyways, NASA came up with a proposal about explosion propelled space ships.

Project Orion

Project Orion

They would have a thick metal shield at the back. At set intervals a nuclear explosion would be set off and the shock waves would accelerate the space ship. With each explosion, the mass of the ship would decrease and it would accelerate even more , eventually reaching relativistic speeds. That would technically allow us to access the stellar neighborhood, if not the entire galaxy.

Alas! Fusion’s too Good for our Technology…

Fusion requires extremely high temperatures (millions of Kelvin) to occur. And no material known to man can withstand the heat. Scientists are still experimenting with magnetic  and inertial confinement. In magnetic confinement, the hydrogen plasma is confined within a solenoid so that it does not touch the surface or the container. In inertial confinement, beams of lasers heat up the particles in suspension to cause fusion. you can read more about these two methods here.

Fusion Reactor

Fusion Reactor

In the end, we’ll have to just wait for and see,

For a Genius of a Man to Solve the Mystery.

But if you really think that you are Worthy,

Step forth, Champion, and Tame the WMD!

Last semester, I took some poetry,

It seems some of it rubbed off on me.

I will stop now.

image1, image 2

Trous Noirs And trous noirs

For an explanation of the title, see the link at the end.

If you are seriously, irreconcilably frustrated by your significant other (or lack thereof) and you never want to see your significant other (or yourself) ever again, please accept a sincere piece of advice from me: Do not- I repeat: DO NOT throw them(or yourself) in a black hole. That would be a bad idea.

"I wasn't gonna push her!"

“I wasn’t gonna push her!”

Now the sensible will decimate my sagely wisdom because of the sheer improbability of a black hole ever crossing two recently uncrossed star crossed lovers. But the curious(and the willing) will ask: Why?

Because the face of the victim will adorn the cosmos for the rest of your life. That kind of kills the point of throwing someone into a hole which never spits anything out. Why?

In my previous article I wrote about how a black hole is formed. Now I will write about why black holes are great advertisement spots and potential reminders of every regretful thing you did in your life. Einstein pointed out in his general theory of relativity that gravity distorts space and time. So for an observer at an arbitrary distance, a clock near a massive object will appear to run slow. The nearer the clock is to the object’s center, the stronger will be the gravitational field, and the slower it will run (for less massive objects the clock will have just to be nearer to the center). However, there is a problem with heavy objects: they are usually very large. Therefore a clock won’t be able to get closer than the radius of the object. So the effects of time dilation won’t be apparent.

Black holes, however, have a zero radius. So objects can get close enough to experience significant relativistic effects. I will be using the case of you, and your significant other (real or imaginary) who recently lost his/her position of significance (and their balance on the space ship, apparently; sshhhh!):

time_dilation_gravity

In this picture, the green line represents the time measured by the observer(you) away from the influence of the black hole. The red line represents the time measured by the, uh, test subject. According to you, your time proceeds normally (the green line is not warped). The red line, even though it appears distorted to you, appears straight to the subject; just like you only have to walk straight without a care for the earth’s curvature to go to your destination, even though you appear to be moving in an arc to an observer in space. The numbers on both lines represent the hours elapsed since the break-up. Notice that the length between the hour intervals is the same for both green and red.

Now imagine that you both have clocks. Assume that the subject’s clock sends out a signal every hour. Also assume, for the sake of simplicity, that the signal reaches you instantaneously. As the warping of space time increases with decreasing distance to the black hole, you will get consecutive signals at ever increasing intervals, until at one point the next signal will take infinite time to reach you. However according to the subject, time will seem to pass normally because according to the subject, the red timeline is perfectly straight (just like with you and the earth). As you can see from the picture, no matter how far into time you progress, you will still get signals from the clock. That is to say, the simple act of disappearing forever will take your significant other an unimaginable long amount of time; and they wont even notice that you are getting impatient. As I said: bad idea.

To understand how the timelines work click here.

An explanation of the title here.

Relativistic Doodles

This post explains how my illustration of general relativistic time dilation works. This is the parent post.

Here is an image of a simple classical timeline:

timeline_1

There are 2 observers: green and red. They have their own watches. The red observer shoots an arrow towards the green observer. The position of the arrow vs. the time recorded by the two observers looks like the picture above. If we take a trace of the trajectory of the arrow, we get:

timeline_2

If we were to take the trace of a 2 signals 1 second apart that travel at constant speed, and 2 signals 1 second apart and traveling instantaneously, we would get:

timeline_3

You will notice that the components of all 4 traces (like the ones drawn in grey) are parallel and perpendicular to the space-time axes. This is always the case. So even when I distort the edge of the red timeline a bit, I get:

timeline_4

So if I am standing with the red observer, and I see him sending out signals, I will not notice a difference even when the red timeline distorts, because to me, the components of the signals are still parallel and perpendicular to my space and time. In the same way, when an observer is falling into a gravity well (like that of a black hole) and sends out signals, the observer does not notice the relativistic effects of gravity on the signal. However, the observer who is standing far away from such distortions notices an altered signal. So even though the signal at t=8 was instantaneous according to the red observer, it reached the green observer at t=9.

If you understood this, then you will know what is wrong with this set of traces of signals that a red observer sends as she falls into a black hole:

time_dilation_gravity_WRONG