Monday, February 4, 2008

Nothing Can Move In Spacetime

Dr. Mark Chu-Carroll, PhD Computer Scientist

Not too long ago, Google software engineer, self-appointed anti-bozo crusader and PhD computer scientist Mark Chu-Carroll (yet another insufferably pompous computer geek, ahahaha…) got terribly offended by my web page Nasty Little Truth About Spacetime Physics. Of course, Mark is offended, not because of my arguments (which went over his head) but because I make fun of a bunch of scientists such as Stephen Hawking, Godel, etc... Mark decided that my problem is that I don’t understand what a dimension is. So, Mark goes into a tirade of outright indignation that is somewhat funny in its own right, especially when, all the while, Mark has half his foot planted squarely in his mouth. Yep, like a bozo.

I really don’t feel like defending myself against Mark’s accusations and crackpottery here simply because I’m tired of it. The fact remains that, Mark’s protestations notwithstanding, time cannot change by definition and, as a result, nothing can move in spacetime. I’ll just repeat a quote from a textbook written by a well-known relativity expert:
There is no dynamics within space-time itself: nothing ever moves therein; nothing happens; nothing changes. [...] In particular, one does not think of particles as "moving through" space-time, or as "following along" their world-lines. Rather, particles are just "in" space-time, once and for all, and the world-line represents, all at once the complete life history of the particle.
From "Relativity from A to B" by Dr. Robert Geroch, U. of Chicago

Obviously I am agreeing with a relativist who happens to understand that nothing can move in spacetime. Yes, there are a few out there. Geroch is not alone but most relativists don’t know this and most, like good old Dr. Mark Chu-Carroll, will refuse to accept it simply because it goes against their chicken-shit Star-Trek time travel religion. Too bad.

Stephen Wells

Stephen (I have no idea who he is) posted an objection to my arguments (comment #33) on Mark’s blog that I would like to respond to, not because Stephen deserves a response, mind you, but because my original rebuttal of that particular objection was inadequate. I’ll revise it in a few days to reflect what I write below. Stephen writes:
Now we move to a 4D spacetime model, where a particle trajectory is in (3+1) dimensions. Louis tries to parametrise all four variables (x,y,z,t) in terms of t, declares that parametrising t in terms of t is wrong (which is true), and decides that all of SR and GR is a massive fraud and conspiracy (which is false).

First of all, it is not true that I decided that all of GR is a massive fraud and conspiracy. I actually believe that GR and SR are useful theories as theories go, even though they don't explain much. I just think that all the nonsense about time travel and the like that Einstein’s followers have been preaching over the last century is just that, nonsense. Relativity does not support time travel and relativity does not prove that absolute motion and position don't exist. In fact, there is every reason to suppose that they do and that it is the relative that is abstract and non-existent. Of course, there is no such thing as a particle trajectory in 4D spacetime but Stephen is not about to concede this little truth. He continues:
Meanwhile, back in the land of the sane, we parametrise a worldline (x,y,z,t) in terms of the proper time tau of the particle along that worldline. So we don't parametrise t in terms of t anyway.
So what? Both delta-tau and and delta-t represent temporal intervals. If anybody thinks that a second time can be used to prove that change can occur in another time, I’ve got a bridge to sell you. If you use tau to show a change in t, you must be prepared to show how tau can change. Why? Because time is time. What’s good for the goose is good for the gander. If t can vary, so can tau. To show a change in tau one would need a meta-tau, and a meta-meta-tau for the meta-tau, ad infinitum. And no, you cannot use t to parameterize tau because that would be circular. The expression dt/dtau does not show that t can change. It is just a ratio of two different temporal intervals measured by two different clocks. That is all. Having wrestled his pathetic little strawman to the ground, Stephen valliantly declares victory:
Louis will never grasp this- he can't allow himself to, after decades spent ranting on the subject. Sad, really.

Sad indeed. Entire generations of young minds believing in a lie. Enough to make a grown man cry. Will I ever get an apology from the likes of Stephen Wells and PhD computer scientist Mark Chu-Carroll? I'm not holding my breath.

See Also:

Why Einstein's Physics Is Crap
How to Falsify Einstein's Physics, For Dummies
Why Space (Distance) Is an Illusion
How Einstein Shot Physics in the Foot
Nasty Little Truth About Spacetime Physics
Physics: The Problem with Motion