The Spacetime Metric
Tuesday, November 28, 2006
  too much noise
The most recent episode of Numb3rs featured the phrase "anthropic imbecile." It was spoken by the physicist on the show, Dr. Larry Fleinhardt, in reference to another physicist who had an unusual article published in an eminent- fictional- science journal.
I almost threw a fit, but... a few minutes later, Dr. Fleinhardt endorsed the article and announced that he would be "leaving the planet" on a mission to the International Space Station.
I suspect that most physicists who refer to their colleagues as "anthropic imbeciles" don't vacillate like that too often. The anthropic principle wasn't exactly the most popular subject at the cosmology colloquium. If nothing else, the anthropic principle doesn't make any less sense than multiverse theories or anything similar. The multiverse theories are what are "untestable", not string theory.
Here is a counterexample to a lie that gets circulated throughout physics:
I recently learned that if Q(psi) = q(psi), where capital Q is an operator acting on the wavefunction psi, and lowercase q is an eigenvalue... the ensemble average (expectation value) of capital Q is ALWAYS the same value. This is what it means to be in an eigenstate. Thus, the uncertainty in capital Q is 0. Thus also the idea of uncertainty in one quantity NECESSARILY changing the uncertainty in another gets... thrown out the window.

How long before another idea that's thought to always apply to everything (e.g. the uncertainty principle) gets counterexemplified?
Here's one: the constancy of the speed of light. Why does c have to be constant in vacuum? We know that optical pulses can be accelerated, or even brought to rest, without moving into a medium of a different index of refraction. The speed of light does not have to have one particular value for one particular medium, whether it's air, vacuum, or diamond. If VSL theory is correct (read Faster than the Speed of Light to learn the details), it will cause quite a paradigm shift. We already know that the other elementary constants aren't always constant; H (in cosmology) for example, while not known to great accuracy, has been changing, since the universe is expanding.
Who can say that the speed of light is the same in all reference frames? As odd as this may sound, it's not. From the reference frame of light itself, nothing is happening. Due to the equations of special relativity, which contain the denominator (1- v^2/c^2)^(1/2), if v=c, the denominator reaches 0. Time is not defined for photons. An observer standing on a photon (hypothetically) wouldn't notice anything, because time wouldn't exist for the observer. The observer couldn't measure the speed of everything outside the photon relative to the photon.
If you think that's hard to grasp, start thinking of tachyons. If they even exist, they would go backward in time and propagate with an imaginary velocity. Can we detect them? Probably not.
"THE THEORY OF TACHYONS IS UNTESTABLE! IT'S SO BAD, IT'S NOT EVEN WRONG!"
The Trouble with Tachyons: The Rise of the Imaginary, The Fall of 'Future', And What Comes Previous.
I can see the headlines and book titles right now...
 
Wednesday, November 01, 2006
  end (er's?) game
I recently discovered this article, written by a famous science fiction author.
If you think postmodernism doesn't exist, you're absolutely wrong. This article is an epic of postmodernism.
If you write science fiction but haven't studied "science fact", are you entitled to criticize science?
I agree with Card that a lot of disciplines in the humanities are in trouble. Severe trouble. He asserts that some professors in these departments "...could sound really smart without ever having to check their ideas against the real world." I don't think that the various "studies" departments are worthless, though; the developers of "women's studies", "gender studies", and various race studies were trying to prevent discrimination. He says that a lot of professors in those departments go too far by trying to indoctrinate people. I personally haven't been indoctrinated (or had the chance to be indoctrinated), so I can't comment on that.
However, his discussion of "groupthink" in physics sounds all too familiar. Groupthink is an overused, excessively hyped term. Unlike what a lot of people would have you believe, string theory is not taking over every physics department. RPI has one of the largest departments in the country, but no one here works on string theory. No professor in the department went to the Mensa colloquium, which was only a few miles away. I think it's very obvious that Card's statements are exaggerated, just based on what I see here.
Hey, even the blogger at Angry Physics thinks that the "string wars" are settling down, so hopefully all the negative "attack articles" will cease.
 
A cosmological blog designed to prevent crackpots from ruining professional physics blogs.

Name:
Location: Ocean County, NJ / Rensselaer County, NY, United States

I am an undergraduate at RPI (Rensselaer Polytechnic Institute). I enjoy reading physics blogs because I am working toward becoming a physicist. One of my objectives is to increase scientific literacy, which will prevent crackpots from attacking eminent physics blogs.

ARCHIVES
September 2006 / October 2006 / November 2006 / December 2006 / January 2007 / February 2007 / March 2007 / April 2007 / May 2007 /


Powered by Blogger