I saw The Forbidden Kingdom last night.  It was a fun movie.  And despite it being basically a pure action movie, it also got me thinking about something deeper.  Namely, the nature of time and the universe itself.  Not to give anything away, but the movie shares something in common with Back to the Future: the present is only possible because of events that the main character changed in the past.

[warning: the following may hurt your brain, proceed at your own risk]

Now, the most common theory of time travel you hear about is that the time traveller is actually traveling into an alternate universe.  Thus, a paradox wouldn't arise if you, say, travelled back into the past and caused the death of your ancestors.  You would be able to change the future through your actions, even in a way that would prevent you from being born in that future, because you would actually have been born into a different future (in the universe you started from).  The problem with this idea is that there is no real explanation of how time travel would actually work.  How would you make that jump to an alternate universe?  But there is another way. 

What if the passage of time were an illusion?  Physicists consider time to be a dimension just like the three axes of the spatial dimensions (hence the notion of spacetime).  It is possible that when the universe began, all of time began with it.  The past, present, and future would all exist simultaneously.  Our perception that time only moves forward could be just an illusion, because that is all our minds are capable of perceiving.

This idea is comforting in one sense, because it bestows upon us a sort of immortality.  Even after we die, even if the universe collapses back upon itself, our entire lives will still exist as a timeless pattern through four dimensions.  But this idea is discomforting in another sense... it implies a lack of free will.  There really is no need to worry about that, however.  Whether we really have free will or not doesn't change anything in our lives.  Wether we were pre-destined to make a decision or "chose" to make it, we wouldn't be able to tell the difference.

So what does this all have to do with time travel?  Well, consider the universe.  It exists in three dimensions.  As a three-dimensional region, it has a shape to it.  The general shape could be a sphere, or it could be something more complex.  To see where I'm going with this, consider a flat (i.e. two-dimensional) piece of paper.  Of course, a piece of paper isn't really two-dimensional since no matter how thin it is, it is still made up of three-dimensional partices, but bear with me. 

If you were to draw two dots on opposite end of the paper, the shortest path between them would be a line running across the length of it.  However, if you took the paper and curved it back on itself in the third dimension, you could make the two dots touch.  Although the shortest path in the context of the two-dimensional surface of the paper is still that long line, the shortest path when considering this new third dimension is now reduced to zero. 

If you were a two-dimensional being living within the surface of the paper, you would be unaware of this new path.  You wouldn't be able to see into the third dimension, just as we are unable to see into the fourth dimension (i.e. time).  We only perceive our three-dimensional surroundings in the context of one point in time, wherever (or whenever, you could say) we happen to be.  Similarly, the 2-d being would only perceive its two-dimensional surroundings wherever it happens to be in 3-d space. 

Now, if our 2-d being was somehow able to move past the "edges" of its 2-d universe, it would be able to travel between the faraway spots on the paper instantaneously.  Taking this idea to the third dimension, we have the concept of a wormhole.  If our 3-d space curves back onto itself in the fourth dimension, there can be two points in space that meet and thus could be instantaneously travelled between if we could only break through that "edge."  Physicists believe that the incredible mass and density of black holes might create such large curvatures in space-time that a wormhole may be formed.

Now, finally, we can see how all of this applies to time travel.  We can go one step further, and consider that four-dimensional space-time may curve back onto itself in the fifth dimension, if such a dimension exists.  Voilà!  We now have a wormhole through space and time (e.g. 'the gate of no gate' from The Forbidden Kingdom).

edit: I recommend this cool animation as a way of visualizing higher dimensions.  It goes over ten dimensions, which interestingly coincides with the predictions of competing string theory models that there are either 10, 11, or 26 total dimensions.  Of course, string theory is still highly speculative at this point, as are the animation's ideas about higher dimensions.

I haven't posted recently, so I'll say a little about what I'm working on.  I rolled out the recommend feature last week (thanks to Ayca for the design and Justin for integrating it into the feed).  Stay tuned for a module you can put on your home page that lists the items you've recently recommended.

update - the recommended module is now released!  (act now, supplies are limited)

1.  I've never owned a video game console (handheld not included).
2.  I think that watching sports is a waste of time.
3.  I have a prescription for contacts but I don't wear them.
4.  I take two showers a day.
5.  My home computer is running win2k.  I've had it for 6 years.

I just answered this Featured Question, you can answer it too!

And now, a comic illustrating proper usage of the phrase "that's what she said":

Dear L.A. Sheriff's Dept.,

Please put Paris Hilton back in jail where she belongs, to maintain at least some semblance that celebrities must follow the same laws as everyone else.

Sincerely,
A concerned citizen

update: The judge ordered Paris Hilton back to jail today, and she's already back in!  That gives me hope, but right now she's just staying in the medical ward while her lawyer appeals her sentence.  We'll have to wait to see if justice truly prevails in the end.

update #2: I am amazed by some of the comments from people defending Paris' release.  She obviously has no respect for the law and thinks she is above it.  She was almost proven right in this case.

This was not an unfairly harsh sentence.  Paris was a menace on the road and hopefully she realizes that now.  After getting her license suspended and put on probation for drunk driving, she just kept right on driving.  Even after being caught doing this once and not punished for it, she was caught yet again, this time going double the speed limit and without any headlights on at night.  It is lucky that nobody has been injured so far from her reckless driving.  The fact that she tried to appeal her sentence both before going to jail and again after, despite the fact that she was clearly guilty, again showed that she thought she could get away with it.

For me this is not about hating Paris.  I think that she leads an utterly vacuous existence, but I don't hate her.  This is about fairness and equality for all people under the law.  For every person like Paris who gets away with things because of money or fame, there is a poor person somewhere getting a more severe punishment than they deserve because they don't have the money to hire a team of lawyers.  Paris' release from jail was yet another example highlighting the inequities in our justice system.

Now I hope you understand why Paris needed to serve out her sentence.  L.A. City Attorney Rocky Delgadillo put it well when he said that "This decision sends the message that no individual -- no  matter how wealthy or powerful -- is above the law. Today, justice was served."

Alright, I was tagged to post screenshots of my desktop so here we go :O  The first screenshot is what it looks like without any fullscreen apps, and the second is what it more often looks like.   In the first screenshot you can see my minimalist blue background.  My IM clients are open on the vertical monitor on the left, as is Firefox.  On the right side are my instances of Visual Studios containing secret Xanga codez.

Mary and I have just released weblog tags into the xangan wilderness!  If you didn't know, we've already released tags for photos and videos, and soon to be audio as well.  Right now, only the user-level tag pages are available for weblogs, but the global pages will be coming soon!  You can add tags to your posts in the editor (if you don't see a tags field, you may need to switch to a different version of the editor).  You can view the tags on a given weblog on the left-hand side of the page, and you can view all of a user's tags at a url structured like http://www.xanga.com/patrick/tags. Tags are meant as a way of organizing your own content (which you can start doing now) and of discovering other people's content that is of interest to you (once the global pages are available).  So, start tagging away!

edit: Global weblog tag pages are now available!  Check out http://www.xanga.com/tags

Interested in being one of the first to try out the beta version of our new (and much improved) way of choosing what makes it to featured content?  Just check out these posts by Matt and Jeff and leave them a comment, and you may be able to do just that! ;)

Edit: Matt and Jeff just had to go and change their user names, so I fixed the links to their posts
Also, boost is now open to everyone!  so go check it out at boost.xanga.com

It is a constant source of wonderment to me how people in NYC can be so ignorant when it comes to a rather simple concept: intersections. The city’s streets are home to a never-ending war between two opposing forces... vehicles and pedestrians. Both sides employ a variety of dirty tactics in order to gain any kind of temporary advantage.

The Pedestrians

What they lack in size and momentum, they make up for in tenacity.

These warriors of the sidewalks often step several feet out from the curb in an effort to intimidate oncoming traffic. If a car is foolish enough to slow down in order to avoid hitting them, they seize upon this moment of weakness as justification to walk right in front of the vehicle, forcing it to stop completely. The most elite pedestrians don't bother with these kinds of newbie tactics and just start walking across the road regardless of any vehicular deterrence.

The brave men and women on the front lines pave the way to victory for their comrades. Seeing that cars must slow down anyway so as to not obliterate these zealots, the rest of the troops take the opportunity to cross as well. A steady stream of foot traffic continues the barrage until the walk signal is illuminated, at which point the more timid troops who remained on the curb during this ordeal scurry across.

The Vehicles

These road warriors are at somewhat of a disadvantage in this perpetual battle. Since their collisions with pedestrians invariably end up harming the pedestrians far more severely, they are given most of the responsibility of avoiding such occurrences.

However, the bolder among them are still inclined to play chicken with the pedestrian zealots and curb-steppers, daring them to try stepping further out onto the street. The most reckless simply speed up as they approach the intersection, determined to frighten pedestrians back onto the relative safety of the curb and give their vehicle brethren a brief respite.

Another favorite tactic is the barricade. During this maneuver, a convoy of vehicles enters the intersection as the light turns red, even though the traffic on the other side is already backed up into the crosswalk. Pedestrians are then forced to weave their way between cars in a Frogger-like fashion as the traffic starts to move again. In some cases, a truck or bus will time things such that the middle of it ends up squarely in the middle of the crosswalk, forcing pedestrians to walk far and wide out of their way to get around it, or else stand there waiting until it eventually moves again.

John gave most of the pertinent info in his post, but if you have a question about the ratings system let me know!

On a somewhat related note, isn't it interesting how Fox News decided to air a special about sexual predators on Xanga now that Fox and Myspace are owned by the same company?  And here I thought Fox News' credibility couldn't sink any lower...