Wednesday, June 29, 2005

a fish for mysfit


go on, then, darling, chop off its head & add it to time soup.

according to an article in the NY Times, "A Remembrance of Things Future", which yes you need to register to read:
Space and time, some quantum gravity theorists say, are most likely a sort of illusion - or less sensationally, an "approximation" - doomed to be replaced by some more fundamental idea. If only they could think of what that idea is.

apparently many theoretical physicists believe that now is the appropriate time (hah! what?) for such a fundamental idea to emerge, that a new insight into time - or beyond it - may be required to crack profound problems like how the universe began, what happens at the center of black hole or how to marry relativity and quantum theory into a unified theory of nature.

because as mysfit & i have known for a long time, "Physics gets time wrong, and time is the most familiar thing there is" .

this is a fascinating article, so if you can, read it, but if you're a lazy fish, like me, here's some key points.

the problems with current physics & its approach to time can be summarized thus:

time becomes a function of an event, like distance or velocity. "There is a feeling in philosophy," he said, "that this picture leaves no room for locutions about flow and the passage of time we experience."

there is also the (fanfare please) Arrow of Time, e.g. The fundamental laws of physics don't care what direction time goes. so then what about the distinction between future & past?

& of course, how the hell are we supposed to unify the theories of relativity with quantum mechanics? they don't jive. Relativity is smooth & serene, like an aging aristocrat. Quantum mechanics throws raucous keg parties in her parlor. so what about the beginning of the universe, when everything was so small that quantum has to apply? even old ladies were young once.
Looked at closely enough, with an imaginary microscope that could see lengths down to 10-33 centimeters, quantum gravity theorists say, even ordinary space and time dissolve into a boiling mess that Dr. John Wheeler, the Princeton physicist and phrasemaker, called "space-time foam."

so then what about superstring theory? music of the spheres & all that?
according to the article, Physicists say they have a sense of how space can emerge, because of recent advances in string theory, the putative theory of everything, which posits that nature is composed of wriggling little strings.

Calculations...have shown how an extra dimension of space can pop mathematically into being almost like magic, the way the illusion of three dimensions can appear in the holograms on bank cards. But string theorists admit they don't know how to do the same thing for time yet.


ooh, goody, extra dimensions. so when do we start talking about wormholes?

Somewhat to Einstein's surprise, in general relativity it is possible to beat a light beam across space. That theory, which Einstein finished in 1916, said that gravity resulted from the warping of space-time geometry by matter and energy, the way a bowling ball sags a trampoline. And all this warping and sagging can create shortcuts through space-time...but physicists dismissed them because calculations predicted that gravity would slam them shut...

some physicists have imagined that such holes could be kept from collapsing and thus maintained to be used as a galactic subway, at least in principle, by threading them with something called Casimir energy, which is a sort of quantum suction produced when two parallel metal plates are placed very close together. According to Einstein's equations, this suction, or negative pressure, would have an antigravitational effect, keeping the walls of the wormhole apart.

If one mouth of a wormhole was then grabbed by a spaceship and taken on a high-speed trip, according to relativity, its clock would run slow compared with the other end of the wormhole. So the wormhole would become a portal between two different times as well as places...

These speculations have been bolstered (not that time machine architects lack imagination) with the unsettling discovery that the universe may be full of exactly the kind of antigravity stuff needed to grow and prop open a wormhole. Some mysterious "dark energy," astronomers say, is pushing space apart and accelerating the expansion of the universe. The race is on to measure this energy precisely and find out what it is.


(giggles maniacally) a race against time, neh?

have the brain cells for an abstract on "Phantom energy traversable wormholes"? but be warned that nobody knows if phantom, or exotic, energy is really allowed in nature and most physicists would be happy if it is not.


(you can click on these graphics & read them okay, but the article has full versions available.)

in conclusion, Farscape was definitely on to something with the (angry salute) Wormhole Weapon: In another recent paper, Dr. Amos Ori of the Technion-Israel Institute of Technology in Haifa describes a time machine that he claims can be built by moving around colossal masses to warp the space inside a doughnut of regular empty space into a particular configuration, something an advanced civilization may be able to do in 100 or 200 years...Random microscopic fluctuations in matter and energy and space itself, they argue, would be amplified by going around and around boundaries of the machine or the wormhole, and finally blow it up.

so...really...what is time soup?
i dunno. ask mysfit.

"By convention there is space, by convention time," Dr. David J. Gross, director of the Kavli Institute for Theoretical Physics and a winner of last year's Nobel Prize, said recently, paraphrasing the Greek philosopher Democritus, "in reality there is. ... ?" his voice trailing off.

12 little fish:

Blogger mysfit swam up to say...

im not sure it's a problem with our physics - there's this part of me that whispers, like a voice from the future, that scientists, will never "travel" back in time, but will realize what i have ever known, time does not exist, foreward or backward, but my perspective does and i travel both ways in this imaginary thing called time...
put more solidly perhaps, if i perceive my perspective in reverse then i would "travel" in reverse and i do so passively with memories but it is active "travel" that scientists seek.

12:53 PM  
Blogger jenn see swam up to say...

i may start telling people that "exotic energy is not allowed. by order of natural physics."

& i've definitely got to find a way to work "space-time foam" into my vocabulary.

1:22 PM  
Blogger theleftsock swam up to say...

uh... what did you just say?

1:42 PM  
Blogger jenn see swam up to say...

space-time foam!!!!!

1:45 PM  
Blogger theleftsock swam up to say...

gotcha

1:59 PM  
Blogger oldben swam up to say...

holy wars, phantom power...

can you imagine the mess that people would make if time travel became available to the public? forget mailorder brides from russia, how about mailorder brides from feudal europe? or thirtieth century tokyo? i could go back in time and start the beatles a year earlier. i could show up the battle of gettysburg with a couple of semi-automatic pistols or, better yet, a harrier jet. i'd blow minds all thru time, and those are just a few of my ideas.

nay, the question with time travel is not could we do it, but should we?

2:00 PM  
Blogger jenn see swam up to say...

from the article:

Saving Grandpa

But what about killing your grandfather? In a well-ordered universe, that would be a paradox and shouldn't be able to happen, everybody agrees.

Being a good physicist, Dr. Polchinski phrased the problem in terms of billiard balls. A billiard ball, he suggested, could roll into one end of a time machine, come back out the other end a little earlier and collide with its earlier self, thereby preventing itself from entering the time machine to begin with.

Dr. Thorne and two students, Fernando Echeverria and Gunnar Klinkhammer, concluded after months of mathematical struggle that there was a logically consistent solution to the billiard matricide that Dr. Polchinski had set up. The ball would come back out of the time machine and deliver only a glancing blow to itself, altering its path just enough so that it would still hit the time machine. When it came back out, it would be aimed just so as to deflect itself rather than hitting full on. And so it would go like a movie with a circular plot.

In other words, it's not a paradox if you go back in time and save your grandfather. And, added Dr. Polchinski, "It's not a paradox if you try to shoot your grandfather and miss."

"The conclusion is somewhat satisfying," Dr. Thorne wrote in his book "Black Holes and Time Warps: Einstein's Outrageous Legacy." "It suggests that the laws of physics might accommodate themselves to time machines fairly nicely."


i know, i know, this is a long-winded comment. but it's a good article.

but i totally agree with you, oldben.

no one should have that power.

muahahahahahahaha!!!!!

2:36 PM  
Blogger blueboy swam up to say...

They say hindsight is 20/20. My friend told me he had foresight. So I said, "If you have foresight then the past would be unclear and the future would be 20/20." He said, "That's what I have." Mind you my friend was not hallucinating. However I think he may have read some of the type of things posted here.

Comments anyone?

11:36 PM  
Blogger arthur decko swam up to say...

i like the space time foam on my latte....actually, this was a pretty cool article and makes me want to sign up for the ny times, thanks for posting it...

8:10 AM  
Blogger Carl V. swam up to say...

Although I'm fascinated with the concept of time, etc. at this point I just can't stop thinking about the phrase "cosmic loaf" from the first picture...that may be my new catchphrase.

Very interesting stuff. I like the theory of time travel that asserts that you cannot mess anything up by traveling back in time because, since its the past, you already did it anyway. Heinlein uses a version of that idea in his Lazarus Long books.

Its all fascinating stuff! It really exercises the old brain!

8:20 AM  
Blogger jenn see swam up to say...

satanic j: 20/20 foresight sounds a little too much like predicting the future, & if the future is predetermined, but you can see what will happen, you try to change it...aaaargh! paradoxes popping up like pansies.
i'll stick with time travel for the moment.

arthur: the image i have of space-time foam is very similar to the froth on a cappuccino, only...more space-timey. maybe a little bit blue.

carl v: cosmic loaf is another good one. mmmm...fresh cosmic loaf with homemade time soup.

i have way too much to say about heinlein to sum up right now, but i'll get around to it one of these days.

11:47 AM  
Blogger mysfit swam up to say...

maybe

11:38 AM  

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