Quantum teleportation

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Posted October 28th, 2008 in Quantum 3. Tags: , , , .

Teleportation, a term originally coined by science fiction, refers to a hypothetical technology that can transport objects (or, eventually, people) nearly instantaneously from one location to another without sending the object through the intervening space. Classically, one might approach this problem by attempting to record the states of all the particles constituting the object to be teleported; that information could then be transmitted to a distant receiver and used to reconstitute the object out of raw materials available at the receiver. For many years this approach to teleportation was considered implausible because of quantum mechanical concerns. For instance, a teleportation device must somehow record the precise positions and momenta of all atoms in an object in order to reconstruct the object on the other side. This simultaneous measurement of non-commuting observables is forbidden by the uncertainty principle. A more fundamental problem exists, though, which is evident even in situations where the uncertainty principle is not directly applicable. To illustrate this point, consider the teleportation of a (more…)

Any FTL signal can be sent back in time

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Posted October 27th, 2008 in Relativity 2. Tags: , , , .

One surprising consequence of Einstein’s special theory of relativity is that any signal traveling faster-than-light (FTL) can be used to send a message to the past. Special relativity divides the entire universe into three distinct regions as seen by any observer: (more…)

Global counterterrorism strategy

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Posted October 24th, 2008 in Politics. Tags: .

I’m often confused by other peoples’ political positions. For example, I’ve quoted a position that confuses me below. I believe that this statement wasn’t made in jest and may in fact be a widespread opinion- at least in the United States. If you agree with the quote below, please help me to become less dumb by explaining the reasoning that would lead someone to hold this position.

After 9/11, Gore would have made some big talk in front of the U.N. about terrorist groups. But the U.N. would have done exactly what it did do: nothing. The terrorists would have seen us as unwilling to defend ourselves and would have made subsequent attacks on us. This cues more rhetoric from Gore and eventually he and the U.N. would try to negotiate a truce with the terrorists, which would have given them “legitimate” status and guaranteed more attacks in the future.

I can’t confidently say what Gore would’ve done after 9/11. Frankly, I’m not even sure that (more…)

Quantum entanglement and parallel universes

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Posted October 23rd, 2008 in Quantum 2. Tags: , , , .

In 2007 I noticed a confusing post on Slashdot quoting from an article claiming that the no cloning theorem prevented entangled particles from being used for faster-than-light (FTL) communication. I had never heard of any FTL implications of the no cloning theorem, so I responded to this post to see if a less-dumb scientist could explain this connection to me (incidentally, I’m still waiting- someone please educate me!).

While the resulting conversation didn’t shed any light on the purported FTL implications of the no cloning theorem, DrVomact asked a question that eventually led to an enjoyable discussion (edited for clarity) about quantum entanglement and parallel universes. (more…)

A conversation regarding “intelligent design”

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Posted October 22nd, 2008 in Biology. Tags: , , , , , .

This conversation began when I posted an inflammatory essay about creationism on Slashdot. I was pleasantly surprised with the sophistication of The Famous Brett Watson‘s arguments, and he later agreed to let me display this debate online (edited for clarity) to rescue it from being buried in the Slashdot archives. (more…)

The pink triangle

Posted October 22nd, 2008 in History. Tags: .

The Nazi persecution of homosexuals was strangely contradictory in nature. While officially condemned for their negative effect on the nation’s reproductive rate, gay men often held high offices and rank in the Nazi government and military. In addition, a rigorous legal distinction was drawn between gay men and lesbians. Homosexuality of either gender among non-Aryan races was almost completely ignored. (more…)

Fundamental flaws in general physics education

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Posted October 21st, 2008 in Physics. Tags: , , , , .

After years of serving as a physics teaching assistant at several public American universities, I’ve come to an alarming conclusion: students in today’s general physics courses (i.e. courses that don’t require calculus, intended for non-physicists) aren’t being taught physics. They might be learning how to mechanically calculate answers, but they’re learning very little about the actual scientific process of inquiring about the nature of reality. They aren’t learning how these physical laws were deduced in the first place– which is far more important than the intricate details of those laws. I think this educational deficiency contributes to widespread misconceptions such as the belief that the Earth’s seasons are caused by variations in the distance from the Sun, and the curious notion that toilets flush in opposite directions on different sides of the equator. (more…)

Can art be evaluated objectively?

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Posted October 21st, 2008 in Philosophy. Tags: , .

Art is “good” or “bad” only in a subjective sense, or so I’m always told. But is there really no objective measure by which to judge the merits of a work of art? I believe that there is a limited sense in which art can be objectively evaluated, provided certain definitions are agreed upon.

I think all acts of artistic creation are motivated by a universal human desire for personal expression. Therefore, I propose the following definition for art: “A work of art is an object or performance which is created primarily as an outlet for creativity.” For example, a bucket isn’t a work of art because it’s simply a tool designed to carry water. A painting, on the other hand, is created to capture an emotion or reproduce a scene; it isn’t useful in any utilitarian sense and can therefore be classified as art. (more…)

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