IC Forum Archive

ipslore · Posts: 262

DonMarco wrote:

Dakravel wrote:

I mean. Isn't there a conflict here?

There isn't a conflict because of this weird time dilation effect. Essentially, as you get closer and closer to the speed of light, you move slower and slower through time. Once you've hit the speed of light, you are, presumably, not moving through time at all. Moving faster than that gives you imaginary numbers for your other speeds which doesn't make a whole lot of sense. This implies that moving faster than light is near impossible.

What about if you get a train up to the speed of light, then you walk from the back of the train to the front. Doing so would allow you to move faster than light.

Also, as long ass you dont hit anything or run out of fuel, there's no reason you couldn't accelerate youself past the speed of light in a complete vacuum. The science of how this would be possible is pretty realistic, what with the warp fields. In fact, Star Trek's "warp factor" is how fast they are going relative to the speed of light. Warp 5 is 50% the speed of light and 9.3 is 93% the speed of light. There were these screwball episodes where The Traveler showed up and accelerated them faster than light, and Q once threw them in the Delta quadrant (90 billion million jillion miles away) in ten seconds. The finale had an Enterprise that could go warp 13... that was pretty funny.

Well... no. With the train, from your perspective, the train isn't moving, and you're moving at normal walking speed. According to an outside observer, though, the Lorentz transformation shrinks the length of the train, so that its front and back are the same place. Freaky.

About Star Trek... I don't see where you're getting that from. It's always been my understanding that the warp drive goes faster than light, through unknown science-fictiony technobabble. Possibly gravity waves, which would compress the distance in gfront of the Enterprise, and expand it behind.

Dakravel · Posts: 125

aderack wrote:

The main thing is, I'm just having trouble understanding the why behind this time thing. Why it's neccessary. What it's related to in the great universal machinery, and what would be different if it weren't there (which might not be immediately intuitive). You seem to insist that's a question on the level of "but why must a body at rest always stay at rest unless acted on by an outside force?!" It still seems to me like something that could be clarified more. In a conceptual, rather than mathematical, way.

Well, a big part of it is just electromagnetism. According to Maxwell's laws, the speed of an electromagnetic wave is constant. Period. It has nothing to do with the relative speed of the objects creating the wave, the wave itself will always travel at a constant. Using that and some other stuff, one figures, "hey, that's some crazy crap", and special relativity is born.
There may be a more conceptual way of describing why the lorentz effect (things get smaller as they travel faster) and time dilation happen, but no simple analogies come to mind. Those two ideas however are intensely related.

Technically, we're composed of "four-dimensional particles", since we are capable of moving through time. As for the weirdness of light, I really don't know what to say about that. I could say something along the lines of "Light is the force-carrying particle of the electromagnetic force and happens to be massless" but even then I don't know if that really describes why. Like I said before, I don't know if you can really ask "why" about this stuff. God maybe?

Presumably beings that were capable of movement in the fourth dimension would see time just as we see the first three dimensions. They could go to any point in time they wanted whenever they wanted. Kinda like the aliens in Slaughterhouse Five.
We might think of a two dimensional object stretched out in a very long way. One end of the object could be considered its birth, the other end its death, and we can view every moment at all times.

DonMarco wrote:

What about if you get a train up to the speed of light, then you walk from the back of the train to the front. Doing so would allow you to move faster than light.

Getting a train up to C is going to take a lot of work. This has to do with the fact that at relativistic speeds, an objects momentum (and therefore velocity) is not in direct proportion to the energy of the object but is actually a square root relation I think. That means the faster you're going, the more energy it'll take to go faster. Light is capable of travelling at the speed of light because it's massless. Everything else would take an infinite amount of energy to get up there.

About warp, you can read about it here! Warp 10 is way faster than the speed of light I believe. And uh.., taking Star Trek as science makes me think this post = postcount++.

The long and short of it is you can hypothesize about objects moving at whatever speeds, but nothing has ever been observed to move at >C, and at this point it seems impossible. As things with mass approach C, it gets harder and harder for them to continue accelerating and so, yeah.

DonMarco · Posts: 565

ipslore wrote:

Well... no. With the train, from your perspective, the train isn't moving, and you're moving at normal walking speed. According to an outside observer, though, the Lorentz transformation shrinks the length of the train, so that its front and back are the same place. Freaky.

Regardless of YOUR perspective you would be going faster than light, from someone else's perspective. Especially if that person was standing outside the train.

OKAY

(-2)--------------(-1)--------------0---------------1--------------2--------------3--------------4------->

Every number is one second traveling at the speed of time. So every number is 186,000 miles apart. The train itself is 180,000 miles long.

(-2)xxxxxxxxxx(-1)--------------0---------------1--------------2--------------3--------------4------->

Well the blue xs are the 186,000 mile-long train, traveling between 0 and 1. one second later is looks like this:

(-2)--------------(-1)xxxxxxxxxx0--------------1--------------2------->

Putting a person at the very end, which will be this cyan o, starting at that-person's "second zero" here:

(-2)--------------(-1)--------------0oxxxxxxxxx1--------------2--------------3--------------4------->

One second later the person hasn't moved much. MUCH.

(-2)--------------(-1)--------------0--------------1oxxxxxxxxx2--------------3--------------4------->

Saying you could walk 4 miles in an hour without eating or sleeping, it would take you 46,500 hours, or 1,937.5 days to walk from the back of the train to the front. Now the train has been moving contantly at exactly yhe speed of light. so after 1,937.5 days, or 5.03 light years, it is somewhere like this:

<--------------167399996---------------167399997---------------167399998---------------167399999xxxxxxxxxxxo167400000--------------->

So the front of the train has traveled 167,400,000 seconds and the end 167,399,999 seconds. Had you waited in the seat at the very end of the train, you would've traveled at the same speed as the rest of the train: the speed of light. But by walking for the last five years, you have traveled (167,399,999 seconds x 186,000 miles-per-second + 186,000 mile-long distance walked = ) 31,136,400,000 miles covered. Divide that by the time spent in total (in seconds), 167,399,999.

31,136,400,000___________distance = (speed)
_167,399,999 ______________time

Equals!
186.00000111111111774857298535587 miles per second. Which is faster than 186,000 miles/second. Hense! Faster-than-light.

GRANTED! These numbers are extreme, but only because you are reading them in 2005. If someone had told you back in 1989 that in 15 years you could fit all the video games known to man on something the some of a postage stamp and play them on one system, you would say they were crazy. They would then say they were all free and collected in less than 10 seconds, and you would punch them in their face. Go back a millenium and tell som poor book transcriber that in your time printed books cost less than a meal and are created 15,000 at a time. The tell them that most readable words aren't on paper, but microscopic crystals that create any shape or color in magical tablets.

Psiga · Posts: 3990

You know, I still can't tell if he's serious.

Ediiiit: So, hey. For starters, let's say that you've accellerated a train to the speed of light. In the process of doing this, the blue-shift of moving toward light coming at you would drive the oncoming EM radiation into deadly levels that would pass through and/or destroy train materials. You'd have to break a wavefront of oncoming light around the train (perhaps with a sheath of magical matter that makes the light move three hundred times faster than normal?) so you wouldn't be absolutely destroyed by the radiation.

Even then, you have the problem of how quickly the protons and electrons and such that compose atoms are capable of moving through the quantum foam (or whatever flavor-of-the-month cosmic foundation is named). By 'vacuum' they don't mean free space where all other rules are off. Something fundamental is preventing light from moving any faster than it already does. To my understanding, I think modern scientists like to say that the elements of atoms would drag on that fundamental thing as they picked up velocity, which would warp their orbits in such a way that they'd eventually become unstable and collapse. Or require "infinite energy" in order to force their orbits to remain stable.

A better metaphor might be the ghosting that you see on LCD panels. Say that a dot can only move from pixel A to pixel B after pixel A has completely settled. You can't move faster than that, or the dot will smear; you can't skip from pixel A to pixel C, because you're only allowed to move from one square on the grid to an adjacent square on the grid.

This experiment that makes light move up to three hundred times faster than normal is kind-of like being able to make an LCD refresh much faster than usual, but each super-refreshed pixel can only be a random color. You can't move anything useful.

I mean, this is going by my understanding of 'normal' physics. I still think there's more to it than people are accepting right now. A hundred years ago, the New York Times said that man wouldn't fly for a thousand years. Scientific American initially claimed that the Wright Bros. test flight was a hoax. That's what we're dealing with. They're going to piss and moan until they see proof, then they'll rave about how awesome it is without so much as an apology, let alone a lesson learned.

Still, though.. WTF, Marco?

-Psiga

extralife · Posts: 3316

That's because Marco is the boy who cried wolf.

aderack · Posts: 5018

I think I might remember the topic of one of those papers I talked about in the other thread. Something about time actually being two dimensions rather than one. Or, rather, time itself is as linear as any other dimension. Once you factor in potentiality, choice, and whatnot, however, you're talking about moving right and left at various intersections.

So time and potential, I guess, are perhaps two closely-interrelated dimensions, with time being the X and potential being the Y. From our perspective we're hurtling though time, always, inelectably. We can't move forward or back. All we have opportunity to do is choose right or left. To eat broccoli or to eat lima beans. To go to the park or to stay home and masturbate.

If, as Heideggar observes (kind of astutely), Being is time -- that is, our hurling through time is the same thing as consciousness, as awareness, then perhaps this fifth dimension is what we might from a subjective standpoint (whereby we feel we are remedially in control of our actions, rather than simply acting out a role in an infinitely complex causal framework) see as "choice" or "free will".

...

So yeah. It's basically Doctor Who-level stuff. It knocked the socks off of some professors, though.

Back to light. From what we've been talking about, I still can't shake this weird feeling that it's got some greater four-dimensional significance than we're giving it credit for. Like there's some important relationship between light behaving as it does (both wave and particle); moving at the speed it does, which also coincidentally happens to be the fastest relative speed anything can move before things start to break down; and time. Like, I don't know, electromagnetic waves even being measurable within the first three dimensions is somehow a fluke. Like they're not exactly a phenomenon of "normal" space (as we understand it with three dimensions), and yet simply by moving at the speed of light, they're "breaking through" from someplace else.

Except I also get the feeling that that's somehow backwards from what I have in mind, and I should be looking at it from the other side, only I don't know what's over there..